Pediatric

Orthopedic Surgery

 

 

 

Epiphysiodesis‌ Developmental dysplasia of	443	Slipped upper femoral epiphysis: Osteotomy	462
the hip: Closed reduction	446	Tendo-Achilles lengthening	464
Developmental dysplasia of the hip: Open reduction‌	449	Congenital talipes equinovarus correction	469
Developmental dysplasia of the‌		Surgical treatment of Perthes disease	473
hip: Pelvic osteotomy 452 Principles of surgery in cerebral palsy‌			476
Developmental dysplasia of the Guided growth: Temporary hip: Proximal femoral osteotomy 456 hemiepiphysiodesis‌			479
Slipped upper femoral epiphysis: Viva questions			481

 

Pinning	459

 

Epiphysiodesis‌

Preoperative planning

Epiphysiodesis involves destruction of the physis to allow equalisation of leg length discrepancy (LLD) in children. As most growth occurs around the knee, the distal femoral and/or the proximal tibial and fibular physes are targeted depending on the predicted remaining growth.

 

Indications

• Predicted true LLD 2–5 cm at maturity

• May be used to treat LLD greater than 7 cm through lengthening of the short limb and epiphysiodesis of the long limb

  Contraindications

• Apparent LLD

• LLD less than 1.5 cm

• Localised infection

   

• Tumour

• Closed physis

   

  Consent and risks

  • Neurovascular injury: Less than 1%

  • Infection: Less than 1%

  • Fracture: Less than 1%

  • Angular deformity: Less than 1%

  • Residual LLD: 80% patients within 1 cm

   

  Operative planning

  Various methods exist to determine the LLD at maturity and to guide the timing and type of epiphysiodesis (distal femoral and/or proximal tibial):

• Green-Anderson growth remaining method: Estimates growth potential in the distal femoral and proximal tibial physes at various skeletal ages separately for girls and boys.

• Moseley straight-line graph: A logarithmic representation of the Green-Anderson method.

• Menelaus arithmetic method: Assumes growth of 10 mm/year from distal femur and

  6 mm/year from the proximal tibia and that girls reach maturity at 14 years and boys at 16 years.

• Eastwood-Cole method: A graphic representation of the arithmetic method but takes into account non-linear changes in LLD. Bone age is more reliable than chronological age in determining growth remaining and can be calculated using the Greulich and Pyle method. This involves comparison of a left hand and wrist radiograph with a known standard.

  Anaesthesia and positioning

  General anaesthesia is used, together with intravenous antibiotic prophylaxis. The patient is positioned supine with the knee slightly flexed over a small sandbag. A pneumatic thigh tourniquet is used. An image intensifier is required and a gonadal shield should be appropriately placed.

   

  Surgical technique

  Landmarks

  The image intensifier is used to mark the orientation of the physis in the frontal plane and the midpoint of the physis in the lateral plane.

   

  Approach

  A 1–2 cm longitudinal incision is centred over the midpoint of physis medially and laterally. A larger incision is made laterally to identify and protect the common peroneal nerve if performing proximal fibular epiphysiodesis.

   

  Dissection

  Sharp dissection is continued down to bone.

   

  Procedure

  Physeal cartilage is removed using a 4.5 mm diameter drill under image guidance: A single entry point is made in the lateral cortex in line with the physis on the frontal view and at its midpoint on the lateral view. This minimises weakening of the cortex and the risk of subsequent fracture. The drill is advanced transversely along the line of the physis in the frontal view until the tip reaches its midpoint (Figure 16.1).

   

   

   

   

  Figure 16.1 The trajectory of the drill should be checked periodically using the image intensifier to ensure obliteration of the physis.

   

  Using the same entry point each time, the drill is tilted 30° first anteriorly then posteriorly and advanced to the halfway mark to remove a fan-shaped area of physeal cartilage (Figure 16.2). This technique is then repeated on the medial side. The swarf should be

   

   

   

   

   

  Figure 16.2 The drill is inserted in the mid-sagittal line of the femur then angled anteriorly and posteriorly by 30° using the same entry point.

   

  inspected to ensure removal of physeal cartilage. Further curettage of the epiphyseal surface is performed to remove any remaining physeal cartilage.

   

  Closure

  A layered closure is used with absorbable subcuticular material to skin.

   

  Postoperative instructions

• Mobilise full weightbearing with crutches for comfort for up to 2 weeks

• Radiographs at 3 months then periodically until maturity to assess physeal closure and leg lengths

   

  Recommended references

  Atar D, Lehman WB, Grant AD et al. Percutaneous epiphysiodesis. J Bone Joint Surg Br. 1991;73:173. Eastwood DM, Cole WG. A graphic method for timing the correction of leg-length discrepancy. J Bone

  Joint Surg Br. 1995;77:743–747.

  Menelaus MB. Correction of leg length discrepancy by epiphyseal arrest. J Bone Joint Surg Br.

  1966;48:336–339.

  Snyder M, Harcke HT, Bowen JR et al. Evaluation of physeal behaviour in response to epiphysiodesis with the use of serial magnetic resonance imaging. J Bone Joint Surg Am. 1994;76:224–229.

   

  Developmental dysplasia of the hip: Closed reduction‌

  Preoperative planning

  Although often combined with an arthrogram and soft tissue releases, technically this remains a closed procedure as the capsule is not opened. Adductor and psoas releases are performed via an open medial approach, the technical details of which are provided in the section ‘Developmental dysplasia of the hip: Open reduction’ (p. 449).

  The optimum timing of reduction is subject to debate: Waiting for the capital femoral epiphysis to appear reduces the risk of avascular necrosis although, conversely, early reduction suggests a better long-term outcome.

   

  Indications

• 6- to 18-month-old child with developmental dysplasia of the hip (DDH)

• Failed treatment with Pavlik harness

   

  Contraindications

  This is contraindicated in a child less than 6 months or older than 18 months.

   

  Consent and risks

  • Application of spica plaster in the human position; subsequent care must be explained to parents

  • Avascular necrosis: 5%–10%

   

   

  • Re-dislocation: Less than 5%

  • Further surgery: 20%

  • Neurovascular injury and infection: Less than 1% (if arthrogram and soft tissue releases performed)

  • Risk of conversion to open reduction: 10%–20%; greater risk for high-riding dislocation

   

   

  Operative planning

  Imaging studies are requested depending on the expected presence of the ossific nucleus:

• Dynamic ultrasound if less than 6 months of age to determine alpha and beta angles, reducibility and capsular laxity.

• Plain anteroposterior (AP) pelvis and frog lateral radiographs if older than 6 months. Note any delayed appearance of ossific nucleus, Shenton, Hilgenreiner and Perkins lines, acetabular index and Tonnis grade.

   

  Anaesthesia and positioning

  General anaesthesia is used. The patient is positioned supine at the end of a radiolucent table, to allow image intensifier access. The surgeon stands between flexed, abducted and externally rotated hips.

   

  Surgical technique

  Examination under anaesthesia (EUA) and arthrogram are first performed to assess reduction and the need for adductor longus, gracilis and psoas release.

   

  Landmarks

  The landmark is the adductor longus muscle – palpable in the child’s groin (Figure 16.3).

   

  Procedure

  A 22G spinal needle is introduced beneath the palpable adductor longus tendon in the groin and advanced cranially towards the ipsilateral scapular until the tip is felt to traverse the hip capsule. The position is confirmed with image intensifier before instilling 0.5 mL of diluted contrast.

  The hip is reduced with a combination of flexion, abduction and anterior displacement without excessive force. Soft tissue releases should be considered if this does not occur easily. If the head appears to stand out from the acetabulum on the arthrogram, this suggests a block to reduction such as an infolded labrum. A conversion to open reduction may therefore be required.

  The stability is assessed within the safe zones of flexion and abduction. Typically, a stable position is 90° of flexion and 30°–50° of abduction. Extreme positions increase the risk of avascular necrosis and must be avoided.

   

  

  Figure 16.4 Child plastered in the ‘human position’.

  A well-padded spica plaster is carefully applied in the human position before final radiographic confirmation of reduction (Figure 16.4).

   

  Postoperative instructions

• Plaster check prior to discharge

• Limited slice computed tomography (CT) at 2/52 to confirm maintenance of reduction

   

• Convert to abduction brace at 10/52

• Wean out of brace after further 6/52; depending on acetabular development, night-time bracing may continue for up to 1 year

   

  Recommended references

  Kalamchi A, MacEwen GD. Avascular necrosis following treatment of congenital dislocation of the hip.

  J Bone Joint Surg Am. 1980;62:87688.

  Malvitz TA, Weinstein SL. Closed reduction for congenital dislocation of the hip. Functional and radiographic results after an average of thirty years. J Bone Joint Surg Am. 1994;12:177792.

  Ramsey PL, Lasser S, MacEwen GD. Congenital dislocation of the hip: Use of the Pavlik harness in the child in the first six months of life. J Bone Joint Surg Am. 1978;58:1000–1004.

  Severin E. Contribution to knowledge of congenital dislocation of the hip joint: Late results of closed reduction and arthrographic studies of recent cases. Acta Chir Scand Suppl. 1941;63:142.

  Tennant SJ, Eastwood DM, Calder P, Hashemi-Nejad A, Catterall A. A protocol for the use of closed reduction in children with developmental dysplasia of the hip incorporating open psoas and adductor releases and a short-leg cast: Mid-term outcomes in 113 hips. Bone Joint J. 2016;98–B(11): 1548–1553.

   

  Developmental dysplasia of the hip: Open reduction‌

  Preoperative planning

  Open reduction deals directly with soft tissue obstruction facilitating relocation of the hip without excessive force.

   

  Indications

• Children 6–18 months with obstruction to closed reduction (psoas tendon, contracted capsule, ligamentum teres, transverse acetabular ligament and inverted limbus), an unstable safe zone, previous failed closed or open reduction

• Children presenting over 18 months

   

  Contraindications

  The procedure is contraindicated in children less than 6 months old.

   

   

  Consent and risks

  • Application of spica plaster; subsequent care must be explained to parents

  • Neurovascular injury: Less than 1%

  • Infection: Less than 1%

  • Avascular necrosis: 5%

  • Re-dislocation: 1%

  • Further surgery for dysplasia or LLD: 10%–15%

   

   

  Operative planning

  Planning should include radiographs as per closed reduction.

   

  Anaesthesia and positioning

  General anaesthesia with intravenous antibiotics is used. The patient is positioned supine at the end of a radiolucent table. The surgeon stands between the patient’s legs for a medial approach or on the operative side for an anterior approach. An image intensifier is required.

   

  Surgical technique

  A medial approach is used if the patient is less than 12 months old; an anterior approach, via a bikini incision, is preferred if the child is older.

   

  Medial approach

  Landmarks

  The adductor longus tendon is a landmark – palpable in the groin, approximately 2 cm lateral to the labia/scrotum.

   

  Incision

  A 2.5 cm, vertical skin crease incision is centred on the palpable tendon of adductor longus.

   

  Superficial dissection

   

  Structures at risk

  • Anterior and posterior divisions of obturator nerve

   

  The fascia overlying the tendons of adductor longus and gracilis is opened along their length and fractional lengthening tenotomies are performed. Adductor magnus and brevis are exposed with blunt dissection. Branches of the obturator nerve are identified on the superficial surface of the adductor brevis and are protected.

   

  Deep dissection

   

  Structure at risk

  • Medial circumflex femoral artery

   

  The plane between the adductor magnus and brevis is dissected to access the lesser trochanter. A psoas tenotomy is performed under direct vision avoiding the medial femoral circumflex vessels which pass over the medial surface of the psoas tendon distally.

   

  A medial arthrotomy is made above the vessels, and the acetabular attachment of the ligamentum teres is divided and used as a traction aid to relocate the femoral head. It is then sutured to the anterior inferior capsule.

   

  Anterior approach

  Landmarks

• Anterior superior iliac spine (ASIS)

• Pubic tubercle

   

  Incision

  The line of the inguinal ligament is marked between the ASIS and the pubic tubercle. A second line is then dropped vertically downwards from the ASIS. Next, a 5 cm bikini line incision is marked 2 cm inferior and parallel to the inguinal ligament, one-third of it medial and two-thirds lateral to the vertical line.

   

  Superficial dissection

   

  Structure at risk

  • Lateral cutaneous nerve of the thigh

   

  The interval between sartorius and tensor fascia lata is developed to reach the rectus femoris and gluteus medius.

   

  Deep dissection

  The interval between the rectus femoris and gluteus medius is dissected and the straight head of the rectus femoris is detached from the anterior capsule. It may then be retracted medially to allow psoas tenotomy and L-shaped anterior arthrotomy (see Figure 16.5).

   

  

  Figure 16.5 Anterior approach to the right hip.

   

  Procedure

  Obstructions to reduction are removed as necessary; pulvinar is extracted, the transverse ligament is released and the ligamentum teres excised if obstructive. Adductor releases are performed, via a separate groin incision, to facilitate reduction as required.

  The redundant capsule is tightened with capsulorrhaphy following reduction. Using the image intensifier, the position of maximum stability is identified; the hip is placed in 30° of internal rotation, flexion and abduction and then each of these positions is removed in sequence to determine positioning in plaster and the need for future surgery.

  Femoral osteotomy or an acetabular procedure may be undertaken concomitantly if severe dysplasia is present in an older child.

   

  Closure

• Layered closure ensuring reconstruction of rectus femoris.

• Skin is closed with absorbable subcuticular material followed by a waterproof dressing.

  A well-padded spica plaster is carefully applied in the stable safe zone of flexion and abduction before final radiographic confirmation of reduction. This should be in greater than 90° of flexion without forced flexion and abducted between 30° and 60°.

  Postoperative instructions

• Plaster check prior to discharge

• Limited slice CT at 2 weeks to confirm maintenance of reduction

• Spica removal at 10 weeks and mobilisation allowed

• Follow-up at 3 months with radiographs

  Recommended references

  Ferguson AB Jr. Primary open reduction of congenital dislocation of the hip using a median adductor approach. J Bone Joint Surg Am. 1973;55:671–681.

  Morcuende JA, Meyer MD, Dolan LA et al. Long term outcome after open reduction through an anteromedial approach for congenital dislocation of the hip. J Bone Joint Surg Am. 1997;79:810–817. Wright J, Tudor F, Luff T, Hashemi-Nejad A. Surveillance after treatment of children with developmental dysplasia of the hip: Current UK practice and the proposed Stanmore protocol. J Pediatr Orthop B.

  2013 Nov;22(6):509–515.

  Zadeh HG, Catterall A, Hashemi-Nejad A et al. Test of stability as an aid to decide the need for osteotomy in association with open reduction in developmental dysplasia of the hip. A long term review. J Bone Joint Surg Br 2000;82:17–27.

  Developmental dysplasia of the hip: Pelvic osteotomy

  Various techniques exist for pelvic osteotomy in DDH, and an account of them all is beyond the scope of this chapter. Therefore, only the Salter and Pemberton types are described further.

  Salter osteotomy Preoperative planning Indications

• Acetabular dysplasia; acetabulum faces anterolaterally causing deficient anterior coverage in extension and deficient superior coverage in adduction

   

• Congruent hip

• 18 months to 6 years (as it requires flexibility of symphysis pubis)

  Contraindications

• Bilateral DDH (uncovers contralateral hip)

• Congruent reduction not achievable on EUA arthrogram

   

  Consent and risks

  • Overall risks: Less than 5%

  • Neurovascular injury: 1%

  • Limited weightbearing/crutches

  • Infection: Less than 1%

  • LLD: Gains 1 cm with Salter osteotomy

  • Triradiate cartilage growth arrest (Pemberton osteotomy)

  • Failure of graft

  • Hardware breakage

  • Residual dysplasia (retroversion)

  • Secondary degeneration: Lateralisation of joint increases joint reaction force (Salter)

  • Further surgery (removal of hardware, salvage procedures)

   

   

  Operative planning

  Congruency confirmed with EUA arthrogram.

   

  Anaesthesia and positioning

  General anaesthesia is used, together with intravenous antibiotics. The patient is positioned supine with an ipsilateral sandbag in a position suitable for image intensifier access.

   

  Surgical technique

  Anterosuperior coverage is achieved at the expense of posterior coverage by flexing the acetabular fragment. Typically, the lateral centre edge angle will increase by 10°. It is performed via an anterior approach (see ‘Developmental dysplasia of the hip: Open reduction’, p. 449) extending the bikini incision proximally over the iliac crest to allow splitting of the iliac apophysis and subperiosteal exposure of the ilium to reach the sciatic notch.

   

  Procedure

   

  Structures at risk

  • Sciatic nerve: Rang retractors are placed in the sciatic notch keeping them closely applied to bone to protect the nerve

  • Devascularization/denervation of abductors

   

   

  An osteotomy is performed between the sciatic notch and midway between the ASIS and anterior inferior iliac spine (AIIS) using a Gigli saw. This should appear to be parallel to the acetabular surface on AP images. Hinging on the symphysis pubis, the acetabulum is rotated anteriorly and laterally to gain coverage while avoiding retroversion.

  A wedge of bone from the iliac wing is inserted perpendicular to the weightbearing axis. The ‘winking sign’ should be noted on an image intensifier (foreshortening of ipsilateral obturator foramen) and the position held with two threaded Schantz pins across the osteotomy. Image guidance is used to advance the pins proximodistally beginning just proximal to the ASIS and aiming for the triradiate cartilage (Figures 16.6 and 16.7).

   

   

   

   

   

  Figure 16.6 Salter osteotomy.

   

   

   

   

  Figure 16.7 Radiograph showing left Salter osteotomy and ‘winking sign’.

   

  Closure

• Layered closure ensuring repair of the iliac apophysis

• Absorbable subcuticular material to skin

   

  Postoperative instructions

  Plaster spica for those under 6 years of age. Limited weightbearing with crutches for 6–8 weeks if over 6 years of age.

   

  Pemberton osteotomy Preoperative planning Indications

• Double diameter dysplastic acetabulum

• Congruent hip

• Open triradiate cartilage

• Close to normal range of motion

• No degeneration

• Normal proximal femoral morphology

• Paralytic hip disorders/Ehlers-Danlos syndrome (posterior coverage is maintained, conferring stability)

  Contraindications

• Poor range of motion (flexion, abduction and internal rotation will be further diminished)

• Closed triradiate cartilage

• Congruent reduction not achievable

• Centre of rotation of head and acetabulum coincide

   

  For consent and risks/preoperative preparation/anaesthesia and positioning, see ‘Salter osteotomy’ (p. 452).

   

  Surgical technique

  The Pemberton osteotomy reduces the volume of a large-diameter acetabulum making the centre of rotation of both femoral head and socket coincident. The acetabulum is displaced forwards and laterally hinging on the triradiate cartilage (Figure 16.8). The autograft is stable and fixation is therefore not required. The approach and exposure are performed as per the Salter osteotomy.

   

   

  

   

   

  Figure 16.8 Pemberton osteotomy.

   

  Procedure

  The osteotomy is made 10–15 mm superior to the AIIS passing a curved osteotome posteriorly to reach the ilioischial and iliopubic limb of the triradiate cartilage (midway between sciatic notch and posterior acetabular rim). The acetabulum is hinged on the triradiate to improve coverage. Corticocancellous graft is harvested from the iliac wing and inserted into the osteotomy site. Posterior stability negates the need for internal fixation.

   

  Closure

  This is the same as per Salter osteotomy.

   

  Postoperative instructions

  Instructions are the same as per Salter osteotomy.

   

  Recommended references

  Colemann SS. The incomplete pericapsular (Pemberton) and innominate (Salter) osteotomies. Clin Orthop. 1974;98:116–123.

  Pemberton PA. Pericapsular osteotomy of the ilium for treatment of congenital subluxation and dislocation of the hip. J Bone Joint Surg Am. 1965;47:65–86.

  Salter RB. Innominate osteotomy in the treatment of congenital dislocation and subluxation of the hip. J Bone Joint Surg Br. 1961;43:518–539.

  Thomas SR, Wedge JH, Salter RB. Outcome at forty five years after open reduction and innominate osteotomy for late presenting developmental dysplasia of the hip. J Bone Joint Surg Am. 2007;89:2341–2350.

   

  Developmental dysplasia of the hip: Proximal femoral osteotomy‌

  The varus derotation osteotomy (VDRO) is the most common type performed for DDH.

   

  Preoperative planning

  Indications

• Persistent dysplasia following DDH (coxa valga, anteversion)

• Congruent reduction in abduction and internal rotation

• Reasonable sphericity (lateral portion of head intact)

   

  Contraindications

• Limited range of motion (abduction and internal rotation)

• Active infection

• Pelvic procedure more appropriate (centre-edge angle [CEA] <15°)

• Previous avascular necrosis is a relative contraindication with less predictable results

• Be aware that VDRO will compound an existing negative LLD

   

  Consent and risks

  • Plaster spica if under 6 years

  • Limited weightbearing with crutches if over 6 years

  • Bleeding

  • Neurovascular damage: 1%

  • Infection: Less than 1%

  • Delayed/non-union: 1%–5% (greater risk with increasing age)

  • Failure of hardware: Less than 1%

  • Incomplete correction

  • LLD: Inevitable with closing wedge varus osteotomy

  • Joint degeneration

  • Further surgery (removal of hardware, complex arthroplasty)

   

   

  Operative planning

  An EUA and arthrogram is performed to confirm adequate range of motion and concentric reduction; greater than 15° abduction is required for a varus femoral osteotomy. The type of fixation device and degree of fixed angle are decided (e.g. blade plate/Coventry pin and plate; 90° or 130° angle).

   

  Anaesthesia and positioning

• General anaesthesia

• Supine with ipsilateral buttock sandbag

• Intravenous antibiotic prophylaxis

• Image intensifier

  Surgical technique

  A lateral approach to the subtrochanteric region of the proximal femur is used to avoid compromise to the vascular supply to the femoral head.

   

  Landmarks

  The predicted trajectory of the chosen device along the femoral neck is planned and marked using the image intensifier.

   

  Incision

  A 10 cm longitudinal wound is used, running along the lateral aspect of the proximal femur from the metaphyseal flare of the greater trochanter to the proximal femoral diaphysis.

   

  Superficial dissection

  The longitudinal incision is continued through superficial fat and the fascia lata, in line with the skin incision.

   

  Deep dissection

   

  Structures at risk

  • Perforating branches of profunda femoris artery: These should be identified and cauterised where necessary.

   

  The posterior insertion of vastus lateralis is detached from the posterior intermuscular septum and reflected anteriorly to expose the lateral surface of proximal femur. The periosteum is incised longitudinally and elevated at the site of the predicted osteotomy.

  Procedure

  Beginning from the lateral cortex just inferior to the flare of the greater trochanter, a guide wire is passed up the femoral neck, under image control, without breaching the physis. The trajectory should aim to restore a normal neck-shaft angle of 130°.

  The wire is measured and over-drilled before insertion of the cannulated lag screw. Under image guidance, the proximal osteotomy is made perpendicular to the shaft in the subtrochanteric region using an oscillating saw.

  The second osteotomy is made beginning at the same entry point on the lateral cortex with the saw tilted inferiorly creating a medially based wedge with a lateral apex. The medial cortex is then completed using an osteotome. A guide wire is inserted transversely into the anterolateral cortex distal to the future position of the plate.

  The leg is adducted to close the varus osteotomy, and the guide wire is used as a joystick to externally rotate the distal shaft into a satisfactory position on fluoroscopy (Figure 16.9). Congruent alignment of the lateral cortices should be checked to ensure seating of the plate. The plate is applied over the lag screw, and the distal shaft is reduced onto the plate and held with a Hey-Groves clamp while maintaining correct orientation. Four bicortical screws are inserted to fix the plate before removal of the guide wire. The degree of correction and position of hardware are confirmed with imaging.

   

  

   

   

  Figure 16.9 Stages in varus derotation osteotomy. (a) Valgus, anteverted proximal femur. (b) Screw placed under image guidance. (c) Medially based closing wedge osteotomy performed from lateral side.

  (d) Varus producing osteotomy closed and held with plate following derotation.

   

  Closure

• Layered absorbable closure of vastus lateralis then fascia lata

• Subcuticular absorbable material to skin

  Postoperative instructions

• Mobilise partial weightbearing

• Increase weightbearing status at 6–8 weeks after union confirmed clinically and radiographically

  Recommended references

  Blockey NJ. Derotation osteotomy in the management of congenital dislocation of the hip. J Bone Joint Surg Br. 1984;66:485–490.

  Kasser JR, Bowen JR, MacEwen GD. Varus derotation osteotomy in the treatment of persistent dysplasia in congenital dysplasia of the hip. J Bone Joint Surg Br. 1985;67:195–202.

  Williamson DM, Benson MKD. Late femoral osteotomy in congenital dislocation of the hip. J Bone Joint Surg Br. 1988;70:614–618.

  Slipped upper femoral epiphysis: Pinning‌

  Manoeuvres to reduce the epiphysis are associated with a high incidence of avascular necrosis (40%); pinning in situ therefore aims to prevent further displacement, promote physeal closure and minimise future secondary degeneration.

  Slips are described as stable if weightbearing is possible or unstable if weightbearing is not possible even with crutches.

  Preoperative planning

  Indications

• Grades I—II slip (Southwick angle <60°)

• Bilateral pinning is performed if there is

  • Evidence of bilateral slip

  • Endocrinopathy

  • Younger end of age spectrum (10 years – girls, 12 years – boys)

    Contraindications

• Advanced avascular necrosis

• Active infection

   

   

  Consent and risks

  • Limited weightbearing/crutches

  • Avascular necrosis: 0%–5% but higher if unstable slip

  • Chondrolysis: 10% (greater risk for African Caribbeans, females and poor technique)

  • Fracture: Less than 1%

  • Infection: Less than 1%

   

   

  • Failure of hardware

  • Further slip (associated with inadequate screw advancement)

  • LLD: 1.5 cm difference on average

  • Joint degeneration

  • Further surgery (removal of hardware/osteotomy/arthrodesis/complex arthroplasty)

   

   

  Operative planning

• An AP and Billings lateral of both hips – it is bilateral in 25% of cases (Figures

  16.10

   

  and 16.11)

• Endocrine workup if at younger end of age spectrum

  Anaesthesia and positioning

• General anaesthesia is used.

• Patient is positioned supine on a radiolucent table; care is taken when transferring, preparing and draping the unstable hip to prevent further displacement.

• Intravenous antibiotic prophylaxis is given.

• Image intensifier.

  Surgical technique

  An aspiration of the hip is first performed under image guidance for pain relief and to decompress the retinacular vessels.

   

  25°

   

  

   

   

  Figure 16.10 Patient positioning for Billings lateral radiograph. The hip is abducted, externally rotated and elevated 25° on a foam wedge.

   

   

   

   

   

  Landmarks

  Figure 16.11 Billings lateral radiograph showing slip.

  The image intensifier is used to delineate the joint and proximal femur.

   

  Incision

  As pinning is performed percutaneously, the planned trajectory of the screw is marked in two planes using the image intensifier bearing in mind the course of important neurovascular structures. The entry point of the screw should not be distal to the lesser trochanter as this creates stress risers and increases the incidence of fracture. Preoperative marking also limits the number of guide wire passes necessary to achieve a satisfactory screw position, further decreasing the chance of guide wire misplacement and minimising the risk of fracture. Because the epiphysis is relatively posterior and inferior to the neck, a more anterior entry point is required. Optimal screw position should avoid the posterior neck and posterior superior epiphysis to preserve the blood supply to the femoral head and minimise the risk of avascular necrosis.

   

  Dissection

  Tissues are dissected bluntly down to bone.

   

  Procedure

  A guide wire is passed under image intensifier control to avoid malposition and joint penetration. After measuring and over-drilling the wire, a partially threaded 6.5–7.5 mm

   

  diameter cannulated screw is inserted. A reverse cutting thread is used for easier subsequent removal. Despite an increase in shear strength across the physis using multiple screws, the use of a single screw diminishes the risk of chondrolysis and avoids the disproportionate complication rate of multiple screws.

  The passage of guide wire, drill and screw should be performed under image guidance to avoid joint penetration. The screw tip should reach the centre of the epiphysis, 5 mm from the articular surface with a minimum of three to four threads crossing the physis to provide adequate fixation. At completion, live screening of the hip is performed to ensure solid fixation of the epiphysis and confirm screw position.

   

  Closure

  Subcuticular absorbable material is used to close the stab incision.

   

  Postoperative instructions

  Range-of-motion exercises are begun on the first postoperative day. Mobilisation is then:

• Fully weightbearing with crutches for 2–3 weeks if slip is stable

• Partial weightbearing until healed if unstable

   

  Assessment is carried out at 6–8 weeks for clinical and radiological evidence of union and to ensure that there has not been any further slip. Sporting activities are prohibited until physeal closure occurs. Following physeal closure, screw removal is recommended.

   

  Recommended references

  Givon U, Bowen JR. Chronic slipped femoral epiphysis: Treatment by pinning in situ. J Pediatr Orthop B.

  1999;8:216–222.

  Loder RT, Aronson DD, Dobbs MB et al. Slipped capital femoral epiphysis. Instr Course Lect.

  2001;50:555–570.

  Loder RT, Richards BS, Shapiro PS et al. Acute slipped capital femoral epiphysis. The importance of physeal stability. J Bone Joint Surg Am. 1993;75:1134–1140.

  Phillips SA, Griffiths WEG, Clarke NMP. The timing and reduction of the acute unstable slipped upper femoral epiphysis. J Bone Joint Surg Br. 2001;83:1046–1049.

   

  Slipped upper femoral epiphysis: Osteotomy‌

  An open reduction with osteotomy serves to restore the head-neck angle with subsequent improvement in hip biomechanics. This aims to provide good future function, minimise or delay the onset of painful secondary degeneration, and normalise proximal femoral anatomy for future hip replacement. Osteotomy can be performed at various levels (intracapsular and extracapsular neck, intertrochanteric and subtrochanteric) with greater correction achievable at the site of deformity (more proximally). Although these proximal osteotomies have been associated with a greater risk of avascular necrosis, a Dunn or Fish cuneiform osteotomy performed with meticulous technique, as described later, can achieve excellent results.

   

  Preoperative planning

  Indications

• Slip greater than 60°

• Chronic/acute on chronic or unstable slip

• Open physis

  Contraindications

  Closed physis is a contraindication (Southwick intertrochanteric osteotomy may be more appropriate).

   

  Consent and risks

  • Avascular necrosis: 10%–48%

  • Chondrolysis: 10%–12%

  • Infection: Less than 1%

  • Slip progression

  • LLD: 1–2 cm shortening

  • Further surgery (removal of hardware/complex arthroplasty)

   

   

  Preoperative preparation

  Preoperative AP and lateral radiographs are used to confirm the degree of slip and plan orientation of the osteotomy. Slings and springs are used preoperatively for 3 weeks if acute or acute on chronic.

   

  Anaesthesia and positioning

• General anaesthesia

• Intravenous antibiotic prophylaxis

• Supine on radiolucent table

• Image intensifier

  Surgical technique

  Landmarks and approach

  The osteotomy is performed via an anterior approach (see ‘Developmental dysplasia of the hip: Open reduction’, p. 449). Particular care must be taken not to disturb the posterior capsule or forcefully manipulate the slip to preserve vascularity to the femoral head.

   

  Procedure

  Following longitudinal capsulotomy, the epiphysis must be correctly identified as the anteriorly displaced neck may be mistaken for it. Two osteotomies are required:

• First, an osteotomy is performed perpendicular to the neck at the level of the physis taking more anteriorly to create a wedge. The aim is to leave a convex surface for later

   

  reduction and shorten the neck by 3–4 mm. Over-shortening will lead to instability. Care must also be taken to avoid driving instruments into the posterior capsule, compromising the blood supply.

• Second, an osteotomy is made in the long axis of the neck to remove the bony beak on the side of the slip, again taking care not to breach the posterior capsule. Any remaining callus is carefully removed with a spoon from the posterior capsule.

  Shortening the neck, removing the beak and elevating the posterior capsule allows tension-free reduction of the epiphysis. The epiphysis is reduced onto the neck by placing the leg in flexion, abduction and internal rotation. If insufficient bone has been removed, the epiphysis will not reduce easily, and posterior structures will be placed under tension increasing the risk of avascular necrosis. Shortening and wedging of the neck should cause the epiphysis to overlap the neck anteriorly giving a mushroom appearance. Restoration of the Shenton line and a valgus head-neck angle of 20° should be ensured using the image intensifier.

  While an assistant maintains position, a lateral stab incision is made according to the predicted trajectory of cannulated screw followed by blunt dissection down to the lateral cortex of the proximal femur. A guide wire is then advanced across the osteotomy to hold the epiphysis. Images are checked in two planes to confirm a satisfactory position before definitive screw insertion. Similar to pinning in situ, the entry point should not be below the lesser trochanter, and screw tips should be 5 mm short of the articular surface.

  Dynamic screening allows confirmation of both a solid fixation and satisfactory positioning of hardware.

   

  Closure

• Layered closure including capsular repair with absorbable material

• Subcuticular absorbable material to skin

  Postoperative instructions

• Bed rest with slings and springs for 5 days

• Mobilise 15 kg weightbearing 8 weeks; increase weightbearing status at 8 weeks, after confirming union clinically and radiographically

  Recommended references

  Dunn DM, Angel JC. Replacement of the femoral head by open operation in severe adolescent slipping of the upper femoral epiphysis. J Bone Joint Surg Br. 1978;60:394–403.

  Fish JB. Cuneiform osteotomy of the femoral neck in the treatment of slipped capital femoral epiphysis. J Bone Joint Surg Am. 1984;66:1153–1168.

  Loder RT. Unstable slipped capital femoral epiphysis. J Pediatr Orthop. 2001;21:694–699.

  Vanhegan IS, Cashman JP, Buddhdev P, Hashemi-Nejad A. Outcomes following subcapital osteotomy for severe slipped upper femoral epiphysis. Bone Joint J. 2015;97–B(12):1718–1725.

  Tendo-Achilles lengthening‌

  Preoperative planning

  Various methods for tendo-Achilles lengthening (TAL) exist and may be used in conjunction with other procedures. Percutaneous methods such as the Hoke and DAMP (distal anterior, medial proximal; also called a White slide) technique and open methods such as the Baker

   

  and Vulpius techniques are described (Figures 16.12 through 16.14). The choice depends on the cause, the individual patient and the surgeon’s preference.

   

   

  

   

   

  Figure 16.14 Two techniques of gastrocnemius recession: (a) Baker slide and (b) Vulpius technique.

   

  Indications

• Fixed equinus deformity is defined as an inability to dorsiflex the ankle sufficiently to allow heel contact without compensation in the remainder of the limb or spine. Often, this correlates with dorsiflexion less than 5° and is seen in various conditions such

  as cerebral palsy, congenital talipes equinovarus (CTEV), congenital vertical talus, Charcot-Marie-Tooth (CMT), pes planus and intractable toe walkers.

• Failure of conservative treatment.

• To achieve stump coverage during Chopart’s amputation for congenital malformation of the foot.

  Contraindications

• Rigid bony deformity.

• Pseudoequinus: A false clinical appearance of equinus caused by plantarflexion of the mid- and forefoot (plantaris deformity).

• Medical co-morbidity is not a contraindication as percutaneous techniques can be performed under local anaesthesia.

   

   

  Consent and risks

• The most predictable outcome following TAL is in patients with spastic hemiplegia. The least predictable scenario is seen with percutaneous procedures in patients with diplegia. The two most frequently encountered problems are over-lengthening and recurrence. The former tends to occur following percutaneous procedures on the conjoined tendon, whereas recurrence is associated with recession of the gastrocnemius or soleus aponeurosis.

• Neurovascular damage: The sural nerve in particular is at risk.

• Percutaneous techniques: 1%.

• Open techniques: 5%.

• Plaster immobilisation/limited mobility.

• Complete tendon rupture (percutaneous).

• Wound problems/infection (open): 1%.

• Recurrence (Baker and Vulpius): Less than 5%.

• Over-lengthening leading to crouchedgait: More likely following percutaneous procedures and associated with uncontrolled lengthening in an older child.

• Repeat lengthening: More likely in a younger child and patients with hemiplegia.

• Further surgery (hamstring, psoas or selective gastrocnemius lengthening most often required in patients with diplegia).

   

  Preoperative assessment

  Silverskiold test under anaesthetic differentiates between pure gastrocnemius tightness (increased ankle dorsiflexion with knee flexion) and combined tightness of gastrocnemius and soleus (limited dorsiflexion in knee flexion and extension).

   

  Anaesthesia and positioning

• General anaesthesia or local anaesthesia for percutaneous techniques

• Prone for open or supine for percutaneous techniques

• High pneumatic thigh tourniquet

  Surgical technique

  Percutaneous techniques

  Both Hoke and DAMP procedures are used to treat combined gastrocnemius-soleus tightness. The advantages are improved healing and the option of local anaesthesia. However, these techniques are associated with an increased incidence of over-lengthening and inadvertent complete tenotomy.

  Hoke technique

   

  Structures at risk

  • Tibial nerve – at risk proximally

  • Sural nerve – laterally

  • Flexor hallucis longus muscle – distally

   

  Three points are marked on the tendo-Achilles at 1 cm, 3 cm and 6 cm from its calcaneal insertion. A number 15 blade scalpel is inserted longitudinally in the midline of the tendon at each marked level and then turned through 90° in the desired direction to perform the hemisection while the ankle is dorsiflexed to control the correction. The hemisections are performed on the medial half proximally and distally and the lateral half in the middle incision (see Figure 16.12).

  DAMP technique

  Two 1.5 cm skin incisions are made postero-medially, one 2 cm from the calcaneal insertion and another 5 cm proximal to it. The anterior two-thirds of the tendon is divided distally and the medial half to two-thirds proximally. (This is because of the 90° rotation of tendon fibres in the distal third of the leg.)

  The tendon is divided progressively while tensioning the tendo-Achilles until it yields 5°–10° of dorsiflexion. The medial fibres slide over the lateral fibres, giving length in continuity with a thinned portion of tendon distally and a square cut proximally (see Figure 16.13).

  Open techniques

  These have the advantage of controlled lengthening but carry a greater risk of recurrence.

  Incision

   

  Structures at risk

  • Sural nerve

  • Short saphenous vein

   

   

  A 7 cm longitudinal incision is made, 10 cm proximal to the calcaneal insertion positioned 1 cm medial to the midline to avoid the sural nerve.

   

  Dissection

  The sural nerve and short saphenous vein are retracted if encountered or may be avoided altogether by raising a full-thickness lateral flap. The paratenon is incised longitudinally in the midline to avoid the skin incision, and the medial and lateral edges of the gastrocnemius aponeurosis are exposed.

   

  Baker slide procedure

  Although considered a selective gastrocnemius lengthening, fibres of the soleus aponeurosis are also incised distally. However, this does not lead to over-lengthening as seen in procedures on the conjoined tendon owing to controlled lengthening and inherent stability.

  The medial and lateral thirds of the aponeurosis are incised transversely 12 cm above the calcaneal insertion. A similar incision is then performed across the middle third at least 3 cm proximally to allow side-to-side contact after lengthening. A tongue and groove pattern is created by joining the proximal and distal cuts with two longitudinal incisions (see Figure 16.14). Dorsiflexion of the ankle allows slide-lengthening of the aponeurosis and reveals any remaining fibres that require incision.

  The underlying muscle fibres of soleus are revealed as the aponeurosis is lengthened. Further lengthening should not be performed once 10° of dorsiflexion is achieved on the table, and 3/0 absorbable sutures are placed across the longitudinal portions of the aponeurosis.

   

  Vulpius procedure

  This is used to treat combined gastrocnemius-soleus tightness when plaster immobilisation is not desirable. Instead of a tongue and groove lengthening, an inverted ‘V’ incision is made in the aponeurosis of both the gastrocnemius and the soleus (see Figure 16.14).

   

  Closure

• Tension-free layered closure with buried knots to avoid skin irritation

• Subcuticular absorbable material to skin

   

  With the exception of the Vulpius technique, a below-knee plaster is applied in a plantigrade position. A dorsiflexed position must be avoided to prevent a calcaneus deformity.

   

  Postoperative instructions

  Mobilise weightbearing as tolerated in cast for 4 weeks if used. Convert to night-time splint at 4 weeks and continue for 6 months. Use guided physiotherapy to maintain position and prevent recurrence.

   

  Recommended references

  Baker LD. Surgical needs of the cerebral palsy patient. J Bone Joint Surg Am. 1956;38:313–323.

  Borton DC, Walker K, Pirpiris M et al. Isolated calf lengthening in cerebral palsy. J Bone Joint Surg Br.

  2001;83:364–370.

  Graham HK, Fixsen JA. Lengthening of the calcaneal tendon in spastic hemiplegia by the white slide technique. J Bone Joint Surg Br. 1988;70:472–475.

  Congenital talipes equinovarus correction‌

  Ponseti technique Preoperative planning Indications

  Flexible CTEV

   

  Contraindications

• Rigid clubfoot

• Age over 7 years is a relative contraindication as results are notably worse

 

Consent and risks

• Neurovascular injury (any open procedure)

• Complete Achilles tenotomy

• Plaster impingement/skin ulceration

• Infection (open procedures)

• Stiffness

• Recurrent deformity: Long-term splintage required

• Deformity due to incorrect or incomplete correction, overcorrection or recurrence, e.g. cavus, rocker-bottom, longitudinal breach, flattening and lateral rotation of talus

• 1 cm limb shortening, 2 cm decreased calf girth and smaller shoe by one or half sizes are

common sequelae

Do not expect a completely normal foot; although the Ponseti technique yields good clinical results, foot malformations still exist and can be seen radiographically.

 

Operative planning

The deformity can be graded using various methods. Dimeglio suggests a 20-point scoring system with four grades of severity which correlates with an increasing resistance to correction. The Pirani score helps to predict the need for Achilles tenotomy and is based upon the severity of deformity in the midfoot and hindfoot with a total maximum score of

6. Eighty-five per cent of patients with scores over 5 will require tenotomy.

 

Anaesthesia and positioning

No anaesthesia or sedation required unless the patient is extremely uncooperative. An assistant is essential.

 

Surgical technique

Casting is performed weekly, correcting all three components of the deformity in a predetermined sequence prior to additional operative procedures. At least three toe-to-groin casts are required over a period of 7–10 weeks depending on the severity of deformity.

 

Castings

• Cavus: Caused by a relative pronation of the forefoot due to a plantarflexed first ray. The first ray is elevated with pressure beneath the first metatarsal head to supinate the forefoot and align it with the varus hindfoot. Forced pronation of the foot is avoided as this will worsen the cavus.

• Varus and adductus: Correction of the abnormally internally rotated calcaneus is achieved by external rotation using the lateral talar head as the fulcrum. The cuboid and anterior calcaneus are displaced laterally by applying medial pressure to the navicular anterior to the ankle and pushing the posterior calcaneus medially by lateral pressure posterior to the ankle, ensuring the talar head does not externally rotate. In severe cases, the navicular may not fully reduce although abduction of the cuneiforms more distally will allow correction and the navicular-cuneiform joints will remodel. Once the calcaneocuboid alignment is restored with the anterior calcaneus lateralised, correction of varus can be achieved. The cast must be toe to groin with the knee in

  90° of flexion to maintain abduction and external rotation. This will also treat any associated internal tibial torsion if present. Midfoot pronation must again be avoided to prevent cavus deformity and a midfoot breach.

• Equinus: With the hindfoot varus corrected, serial casts are applied in a progressively dorsiflexed position. This usually requires two to three casts to achieve 15° of dorsiflexion and 60° of external rotation. Dorsiflexion is achieved via pressure beneath the midfoot rather than the metatarsals to avoid rocker-bottom feet.

  Additional procedures

  Tendo-Achilles lengthening: If dorsiflexion of 15° is not achieved, then a percutaneous tenotomy under local anaesthesia is indicated. This is preferable to posterior ankle and subtalar capsulotomy as contraction of scar tissue in this region will lead to progressive loss of dorsiflexion.

  Lateral transfer of the tibialis anterior tendon to the lateral cuneiform may be required for persistent supination.

   

  Postoperative care and instructions

  The final cast is left in situ for 3 weeks and then assessment made for residual equinus; 90% of patients will require Achilles tenotomy.

  Denis Browne boots are worn full time for 2–3 months then at night only for 2–4 years or until age 7 years. These maintain 15° of dorsiflexion (to avoid equinus) and 60° external rotation (to prevent varus, adductus and in-toeing). High-top shoes are worn during the day to maintain position.

  Periodic evaluation should be performed by an experienced clinician to assess the relationship between the hindfoot and forefoot, the attitude of the heel and range of ankle motion. Anteroposterior and lateral radiographs should also be obtained.

   

  Extensive soft tissue release via the Cincinnati incision Preoperative planning

  Indications

• Failed Ponseti treatment: 50% may relapse at an average age of 2.5 years. Remanipulation and casting with or without Achilles tenotomy followed by splintage may be successful although extensive soft tissue releases are required in resistant cases.

• Rigid clubfoot.

• Walking on lateral border of foot/internally rotated gait.

• Posteriorly placed lateral malleolus (a reflection of uncorrected internal calcaneal rotation).

• Parallelism of talus and calcaneus on AP and lateral radiographs.

  Contraindications

  Contraindications include previous releases via alternative incisions.

   

  Consent and risks

  • Neurovascular damage (see later)

  • Plaster immobilisation/impaired mobility/long-term splintage

  • Residual deformity

  • Recurrence and further surgery

  • Wound irritation over the Achilles tendon, particularly rubbing on shoes

  • Avascular necrosis of the talus

  • Arthritis of the hindfoot and midfoot

  • Ankle and subtalar stiffness

   

  Preoperative assessment

• AP and lateral radiographs required for assessing the talocalcaneal angle

• Dimeglio and Pirani scores

Anaesthesia and positioning

General anaesthesia is used with addition of an intravenous prophylactic antibiotic. The patient is positioned prone with a high thigh tourniquet.

 

Surgical technique

Landmarks

The base of the first metatarsal, medial malleolus and lateral malleolus is palpable.

 

Incision (the Cincinnati incision)

An 8–9 cm extensile, transverse incision across the posterior ankle (at the level of the tibio-talar joint) is created. This begins at the base of the first metatarsal, curves below the medial malleolus, rises slightly to traverse the Achilles tendon and continues over the lateral malleolus to terminate distal and medial to the sinus tarsi.

 

Superficial dissection

 

Structures at risk

• Sural nerve laterally

• Superficial venous structures below the lateral malleolus

 

The proximal subcutaneous flap is raised off underlying tissues for around 3 cm to allow proximal visualisation.

 

Deep dissection

 

Structures at risk

• Posterior tibial nerve and vessels

• Deep tibiotalar portion of the deltoid ligament

• Medial and lateral plantar nerves

 

This begins laterally with incision of the calcaneofibular ligament and superior peroneal ligament to allow dissection of the peronei off the calcaneus without damaging them. The lateral talocalcaneal ligament and lateral capsule of subtalar joint are then released. The posterior tibial neurovascular bundle is retracted anteriorly to allow further release of the posterior ankle and subtalar capsule and the posterior talofibular ligament. Subsequent posterior retraction of the tibial neurovascular bundle allows division of the superficial tibiocalcaneal part of deltoid. The deep portion of the tibiotalar portion of the deltoid ligament is left intact to prevent excessive subtalar translation and flat foot deformity.

The tibialis posterior tendon sheath is opened along its length from above the medial malleolus to the navicular to allow Z-lengthening of the tendon at least 2.5 cm proximal to the medial malleolus. The nearby posterior tibial neurovascular bundle is protected to avoid its transection.

Dissection continues medially, into the arch of the foot, to release the lacinate ligament, the plantar aponeurosis and small plantar muscles, including abductor hallucis. Beneath the navicular, the master knot of Henry (intersection of the flexor hallucis longus [FHL] and flexor digitorum longus [FDL]) is taken down, taking care not to damage the medial and lateral plantar nerves on either side of it. The sheaths of the FDL and FHL are opened and tendon Z-lengthening performed to prevent flexion contracture of the toes when the ankle is dorsiflexed. This is done sufficiently proximally to allow the lengthened portions to be covered by tendon sheath. Conjoint lengthening is an alternative if the tendons are too small to perform Z-lengthening. This step may be unnecessary as toe contractures will often stretch out over time.

The talonavicular joint is freed to mobilise the navicular laterally and release all of its attachments; keeping hold of it via the distal end of tibialis posterior tendon will avoid

 

handling the articular cartilage. The dorsal talonavicular ligament and the spring ligament can then be released. Release of the bifurcate ligament and the talocalcaneal interosseous ligament will allow external rotation of the anterior calcaneus.

Finally, the quadratus plantae is stripped off the calcaneus to release the long plantar ligament, the plantar calcaneocuboid ligament and inferior medial capsule of the calcaneocuboid joint without damaging the peroneus longus tendon. The extensive soft tissue releases should result in the plane of the foot being at 90° to the bimalleolar axis with the talus beneath the tibia and slight hindfoot valgus. If the mortise is not fully reduced, tibiofibular ligament release then tibiofibular syndesmosis release can be carried out if the talus is too wide anteriorly. Stabilisation with K-wires is the final stage, one passing along the medial column to hold the talonavicular joint and one across the lateral column to hold the calcaneocuboid joint.

 

Closure

Tendon sheaths over all over-lengthened tendons are closed. The medial and lateral extensions of the Cincinnati incision are closed, without tension, using absorbable sutures to the subcutaneous and subcuticular layers. The posterior, central portion of the wound is left open to heal by secondary intention. If blanching of wound edges following tourniquet release is noted, position in less dorsiflexion.

Apply plaster of Paris from the toes to the mid-thigh with a neutral or slightly plantarflexed foot and the knee flexed to 90°.

 

Postoperative care and instructions

The cast is changed at 10 days after surgery, to inspect the wound. It is removed, along with the K-wires, at 6 weeks. Denis Browne boots are prescribed for the next 12–18 months.

Physiotherapy (for mobility, to promote tarsal growth and preserve cartilage) is continued for at least 6 months.

 

Recommended references

Crawford AH, Marxen JL, Osterfield DL. The Cincinnati incision: A comprehensive approach for surgical procedures of the foot and ankle in childhood. J Bone Joint Surg Am. 1982;84:1355–1358.

Dimeglio A, Benshahel H, Souchet P et al. Classification of clubfoot. J Pediatr Orthop B. 1995;4:129–136. McKay DW. New concept of and approach to clubfoot treatment: section II – Correction of the clubfoot.

J Pediatr Orthop. 1983;3:10–21.

Pirani J, Outerbridge HK, Sawatzky B et al. A reliable method of clinically evaluating a virgin clubfoot.

21st World Congress of SICOT, Sydney, Australia, 18–23 April 1999.

Ponseti I. Congenital Clubfoot: Fundamentals of Treatment. New York, NY: Oxford University Press, 1996.

 

Surgical treatment of Perthes disease‌

Perthes disease occurs as a result of a temporary cessation in the blood supply to the femoral head leading to avascular necrosis. It is commonly seen between the ages of 4 and 8 years although should be suspected from 2 to 12 years of age. Although more common in boys by a factor of four, it may be more severe in girls.

 

Presenting symptoms comprise hip or referred knee pain, stiffness, limping and a short leg. The disease progresses through the four phases of ischaemia (causing collapse and sclerosis), fragmentation, reossification and remodelling, which take place over a 4-year period.

However, development of the hip is frequently abnormal leading to incongruency, altered biomechanics and accelerated secondary degeneration. Prognosis is dependent on age and severity of disease at presentation, and treatment falls into the three broad categories of observation, containment and salvage, depending also on the phase of disease.

 

Preoperative planning

Indications

The type of treatment largely depends upon the capacity to remodel and therefore age. Below the age of 6 years, there is high potential for remodelling, and therapy therefore tends to be conservative. Above 8 years, further remodelling is limited and treatment is more aggressive in order to correct deformity and extend the longevity of the native hip.

Between the ages of 6 and 8 years, the indications for either a conservative approach or containment procedures depend upon bone age and remodelling potential, the presence of ‘at-risk’ signs for the viability of the femoral head and whether the hip is congruent or containable. The surgical options for containable hips are a varus osteotomy of the proximal femur and/or a Salter-type pelvic osteotomy.

Salvage procedures are indicated if hinge abduction occurs (Figure 16.15), where the overgrown and uncontained anterolateral portion of the femoral head abuts the lateral rim of the acetabulum. In this situation valgus extension osteotomy (VGEO) of the proximal femur is indicated, which will medialize the centre of rotation of the hip and make it congruent in the weightbearing position. The medial column must be of sufficient height after reossification and a better outcome is expected in younger patients where the

 

 

 

 

Figure 16.15 Hip arthrogram showing hinge abduction, where dye pools medially in abduction.

 

triradiate cartilage remains open. This will allow deformity correction, a better functional range of movement, improvement of leg length and abductor function.

 

Contraindications

Containment procedures are contraindicated if hips are not congruent or containable.

 

Consent and risks

The natural history of the disease must be explained to the child and parents. It should be emphasised that the aim is to improve symptoms and to achieve a spherical and contained femoral head to maximise and prolong native joint function. However, secondary degenerative changes may continue to occur at an unpredictable and accelerated rate ultimately leading to total joint arthroplasty or arthrodesis.

• An older presentation, particularly in girls, is associated with a worse outcome.

• Stiffness/contractures.

• Other risks pertain to the type of procedure being performed. See the relevant sections on DDH for the risks associated with pelvic and femoral osteotomies.

 

 

Operative planning

Various classification systems exist to guide treatment and predict the prognosis of Perthes disease.

Catterall grouped patients as I-IV, although large intra- and inter-observer error has been shown with this method. The Herring classification correlates with prognosis according to the degree of collapse of the lateral capital femoral epiphysis during the fragmentation phase using the AP radiograph of the pelvis.

The Stulberg classification (1–5) is made during the reossification phase and predicts the end result of Perthes disease dependent on the relative shapes of the femoral head and acetabulum. Increasing grade correlates with the likelihood of secondary osteoarthritis with Stulberg 5 hips likely to require total hip replacement before age 50 years.

Head at-risk signs include Gage’s sign (a lytic ‘rat bite’ at the periphery of the physis), calcification lateral to the epiphysis, lateral subluxation of the femoral head and horizontal inclination of the physis.

Arthrography will determine the congruency of the hip in various positions and whether an appropriate range of movement is possible to perform the relevant femoral osteotomy (Figure 16.15). Significant abduction is required for a varus osteotomy and adduction for a valgus osteotomy.

 

Anaesthesia and positioning

• General anaesthesia

• Supine

• Intravenous prophylactic antibiotics

   

  Surgical technique

• For varus osteotomy, the technique as described in the section ‘Developmental dysplasia of the hip: Proximal femoral osteotomy’ (p. 456) is used, employing the derotation component if required.

• For valgus osteotomy, a similar technique is used as for varus osteotomy, the difference being the orientation of the osteotomy to give a laterally based wedge to achieve the desired realignment.

• Pelvic osteotomy (see ‘Salter osteotomy’, p. 452).

  Postoperative instructions

  Instructions are as per the type of procedure performed. Regular periodic clinical and radiographic review is required to determine the presence of deterioration and the need for further surgery.

   

  Recommended references

  Bankes MJK, Catterall A, Hashemi-Nejad A. Valgus extension osteotomy for ‘hinge abduction’ in Perthes disease: Results at maturity and factors influencing the radiological outcome. J Bone Joint Surg Br. 2000;82:548–554.

  Catterall A. The natural history of Perthes disease. J Bone Joint Surg Br. 1971;53:37–53.

  Coates CJ, Paterson JMH, Catterall A et al. Femoral osteotomy in Perthes disease. Results at maturity. J Bone Joint Surg Br. 1990;72:581–585.

  Herring JA, Kim HT, Browne R. Legg-Calvé-Perthes disease. Part I: Classification of radiographs with use of the modified lateral pillar and Stulberg classifications. J Bone Joint Surg Am. 2004;86:2103–2120.

  Herring JA, Kim HT, Browne R. Legg-Calvé-Perthes disease. Part II: Prospective multicentre study of the effect of treatment on outcome. J Bone Joint Surg Am. 2004;86:2121–2134.

   

  Principles of surgery in cerebral palsy‌

  Preoperative planning

  Cerebral palsy results from an insult to the immature brain and its effects are variable. It may be classified anatomically (hemiplegic, diplegic or total body involvement) or physiologically (spastic, athetoid, ataxic or mixed). The spastic form is most common; a combination of muscle weakness and spasticity leads to a progressive sequence of dynamic deformity, fixed contractures, bony deformity and joint subluxation or dislocation. Depending on the severity, intervention may be indicated at any point during this continuum to optimise energy consumption during gait, to perform activities of daily living, to facilitate standing or seated transfer and to maintain hygiene. Maximum function requires a straight spine over a level pelvis, congruent, mobile hips, mobile knees and plantigrade feet.

  Cerebral palsy is typically treated in one of three phases:

   

• Dynamic contractures: Casting and/or botulinum toxin (BTX) injection

• Fixed contractures: Muscle balancing techniques such as releases, lengthening and transfers

• Bony deformity and joint incongruence: Osteotomies

   

  Decisions around timing of surgery are difficult. Allowing maturation will improve certainty about the gait pattern and reduce the risk of recurrent deformity at the price of an increased chance of fixed deformities and multilevel operations being required. Surgery in the younger child may be less technically demanding but can lead to repeat surgery year on year. In addition, single-level operations may reveal further problems: a common example is a crouched gait occurring after Achilles tendon release due to unrecognised, concomitant tight hamstrings. Throughout all stages, physiotherapy helps to reduce fixed deformity and occupational therapy can adapt equipment to accommodate existing deformity.

   

  Surgical techniques in muscle contractures

  Botulinum toxin A injections

  BTX A inhibits the release of acetylcholine from the nerve terminal at the neuromuscular junction, causing decreased muscle activity in a dose-dependent manner. It may be administered under local or general anaesthesia or sedation. It should be placed deep to the muscle fascia in a dose appropriate for the patient and the number of injection sites required. The injection volume must be sufficient to allow diffusion to endplate zones which may be scattered, particularly in the sartorius and gracilis.

  Localise injection sites using palpation and anatomical knowledge; accuracy is improved with electrical stimulation or ultrasound guidance. Combine injection with casting, orthoses and guided physiotherapy to maximise the benefits.

   

  Contraindications

• Myasthenia gravis

• Aminoglycoside antibiosis

• Non-depolarizing muscle relaxants

• Pseudobulbar palsy

• Gastro-oesophageal reflux or frequent chest infections

   

  Consent and risks

  • Local: Pain, temporary weakness in adjacent muscles

  • General: Mild generalised weakness, urinary incontinence, constipation, dysphagia and aspiration pneumonia

  Parents and patients should be warned of its temporary effect of 12–16 weeks and the risk of recurrence and further procedures.

   

   

  Surgical technique

  Muscle balancing techniques

  Adductor psoas and gracilis release is commonly indicated for the classic flexion adduction contracture and scissoring gait seen in cerebral palsy. Muscle imbalance combined with

   

  infrequent weightbearing causes structural changes at the hip (increased anteversion, posterolateralacetabulardysplasia) leadingtoposterolateralmigration, pelvicobliquityand scoliosis. This is more commonly seen in quadriplegic patients and releases are performed early (3–4 years) to prevent deterioration. Muscles should be released sequentially during the procedure and performed bilaterally to prevent a windswept deformity. Releases are also commonly combined with proximal varus femoral osteotomy at age 5 years.

  Hamstrings may be released proximally or distally to improve flexion contracture at the knee. Equinus deformity at the ankle is very common and is treated with tendo-Achilles release (see section ‘Tendo-Achilles Lengthening’, p. 464 for details). Knee and ankle releases are performed in a walking child between 4 and 6 years old.

  Another common problem is the thumb in hand deformity treated with adductor pollicis release and is performed in the older child. Tendon transfers such as tibialis anterior or tibialis posterior are often used in balancing the foot in combination with bony surgery.

   

  Osteotomy and joint containment

  Hip containment

  Quadriplegic patients should be monitored regularly for hip subluxation and dislocation, which tends to occur between 18 months and 6 years. Hips at risk are those with limited abduction with uncovering of less than 50% on radiography. At-risk hips may be treated with adductor, psoas and hamstring release although a more aggressive approach may be considered. Subluxed hips (>50% uncovered) are treated with soft tissue releases and varus proximal femoral osteotomy.

  Early dislocated hips may be treated with open reduction; however, this may not be possible and poor conformity between the head and acetabulum may lead to early failure. A varus derotational osteotomy with soft tissue releases and/or shortening may be more appropriate. This can be combined with pelvic osteotomy.

  Late dislocations require either resurfacing or total joint arthroplasty; a large articulation is preferred to confer stability. Alternatively, a Girdlestone excision arthroplasty may be considered.

   

  Triple arthrodesis of the ankle

  Various foot and ankle deformities are seen in cerebral palsy such as planovalgus, equinovalgus, equinovarus and calcaneovalgus. Triple arthrodesis is indicated for symptomatic degeneration and uncontrolled deformity. Despite frequent complications such as residual deformity, pseudarthrosis, pain and progressive intertarsal and tarsometatarsal arthritis, the response to surgery is good.

   

  Scoliosis surgery

  Scoliosis is more common in quadriplegic and non-ambulatory diplegic patients. The risk of progression is related to age at presentation and hip problems. Curves are likely to reach 50° if present by age 5. Bracing is seldom preventive. Nutrition must be optimised preoperatively, and patients must be monitored closely postoperatively for respiratory complications.

   

  Indications for surgery are curves greater than 40° or progression greater than 10° per annum. Ambulatory patients receive posterior fusion, whereas non-ambulatory patients require additional anterior fusion and pelvic fixation.

   

  Recommended references

  Gage JR. The Treatment of Gait Problems in Cerebral Palsy. Cambridge, United Kingdom: Cambridge University Press, 2004.

  McCarthy JJ, D’andrea LP, Betz RR et al. Scoliosis in the child with cerebral palsy. J Am Acad Orthop Surg.

  2006;14:367–375.

  Owers KL, Pyman J, Gargan MF et al. Bilateral hip surgery in severe cerebral palsy. J Bone Joint Surg Br.

  2001;83:1161–1167.

  Ramachandran M, Eastwood DM. Botulinum toxin and its orthopaedic applications. J Bone Joint Surg Br.

  2006;88:981–987.

  Skoff H, Woodbury DF. Management of the upper extremity in cerebral palsy. J Bone Joint Surg Am.

  1985;67:500–503.

  Guided growth: Temporary hemiepiphysiodesis‌

  Preoperative planning

  Temporary hemiepiphysiodesis aims to produce a differential growth rate across a physis to allow correction of angular deformities. Several methods have been described to achieve this aim, including use of staples (Blount), percutaneous transphyseal screws (Metaizeau), or more recently the use of a two-hole tension band plate (e.g. 8-plate or Pediplate). This technique is most frequently used for coronal deformities about the knee, although use about other physes has been described.

   

  Indications

  Coronal plane deformity with an abnormal periarticular angle leading to abnormal/ worsening mechanical axis alignment. Occasionally can be considered for correction of sagittal plane deformity (e.g. fixed knee flexion, as an alternative to capsular release).

   

  Contraindications

• Active infection

• Untreated metabolic/nutritional cause for deformity ‘sick physis’

• Insufficient remaining growth

• Non-compliance with follow-up

• Partial growth arrest

   

  Consent and Risks

  • Neurovascular injury

  • Infection

  • Fracture

  • Physeal injury/growth arrest

  • Over-/undercorrection

  • Implant failure

   

   

  Operative planning

  Standardised long leg radiographs should be used for planning with leg lengths corrected using blocks and the patellae pointing forwards. Periarticular angles should be calculated to identify the location of the deformity. The tension band plate should be applied on the convexity of the deformity. Angular correction may be achieved at an average of 0.7° per month at the distal femoral physis and 0.5° per month at the proximal tibia.

   

  Surgical technique

  Anaesthesia and positioning

  General anaesthesia is used with intravenous antibiotic prophylaxis. The patient is positioned supine on a radiolucent table with a thigh tourniquet. A sandbag or leg holder can be used to ensure the patella is pointing upwards.

   

  Procedure

  An image intensifier is used to position a 3 cm incision centred at the level of the physis in the coronal and sagittal planes. Sharp dissection is performed down to, but not through the periosteum. The guide wire is placed approximately 1 cm into the physis and the position checked on AP and lateral radiographs, ensuring that a true lateral view is obtained.

  A suitably sized two-hole plate is passed down the guide wire and positioned, ensuring it is rotated to lie perpendicular to the physis on the lateral view. Two guide wires are placed through the centre of each hole to check the screw will not penetrate the physis or the joint. A cannulated drill is used to open the cortex and a screw is placed in each hole, either side of the physis. The guide wires are removed prior to final seating of the screws.

   

  Closure

  A layered closure is used, using absorbable subcuticular material to skin.

   

  Postoperative instructions

• Full weightbearing is permitted immediately with crutches for comfort.

• Radiographs are performed at 3 months and then at regular intervals to monitor correction.

• Implant removal is required once correction has been achieved to prevent overcorrection.

Recommended references

Ballal MS, Bruce CE, Nayagam S. Correcting genu varum and genu valgum in children by guided growth: Temporary hemiepiphysiodesis using tension band plates. J Bone Joint Surg Br. 2010;92(2):273–276.

Blount WP, Clarke GR. Control of bone growth by epiphyseal stapling: A preliminary report. J Bone Joint Surg [Am]. 1949;31–A:464–478.

Metaizeau JP, Wong-Chung J, Bertrand H, Pasquier P. Percutaneous epiphysiodesis using transphyseal screws (PETS). J Pediatr Orthop. 1998;18(3):363–369.

Stevens PM. Guided growth for angular correction: A preliminary series using a tension band plate. J Pediatr Orthop. 2007;27:243–259.

 

 

Viva questions‌

1. What are the clinical signs of hip instability in the newborn?

2. What are Hilgenreiner and Perkins lines, and what is their relevance?

3. What are the relative advantages and disadvantages of the anterior and medial approaches to the paediatric hip in developmental dysplasia of the hip?

4. Describe the Smith-Petersen approach to the paediatric hip?

5. What are the indications for varus proximal femoral osteotomy in developmental dysplasia of the hip?

6. How does a varus proximal femoral osteotomy affect range of hip movement and leg lengths?

7. What structures are at risk during a Salter pelvic osteotomy?

8. What are the indications and contraindications of the Pemberton pelvic osteotomy?

9. What is the ideal screw position when pinning a slipped upper femoral epiphysis? What risks are associated with this procedure?

10. What are the indications for prophylactic pinning of the contralateral hip in slipped upper femoral epiphysis?

11. How does the blood supply to the femoral head change throughout childhood?

12. What are the treatment options for avascular necrosis following slipped upper femoral epiphysis?

13. What is your approach to the treatment of Perthes disease in a 7-year-old child?

14. What classification systems do you know for grading the severity and predicting the prognosis of Perthes disease?

15. What are the component deformities of club foot, and which structures are tight?

16. Which structures are at risk during extensive soft tissue release of congenital talipes equinovarus via the Cincinnati approach?

17. How would you distinguish between a tight tendo-Achilles complex and gastrocnemius tightness?

18. What methods can you describe to determine when epiphysiodesis should be performed?

19. How much growth per year can be expected from each of the four main physes in the lower extremity in adolescence?

20. What is your approach to the orthopaedic assessment and treatment of the child with cerebral palsy?