Primary Hip Arthroplasty Case Title: Direct Superior Approach

The skin incision is made 45° backward and upward from the tip of the greater trochanter (Fig. 2.1a). The tip area is divided into thirds, and the incision is made between the 2nd and 3rd thirds (Fig. 2.1b, c).

The short rotators are tagged with Ethibond suture size 5 and detached from their base for reat-

tachment after the end of surgery (Fig. 2.1d, e). The capsule is also tagged and will be reattached in layers at the end. The gluteus medius and minimus are protected using the ring retractor (Fig. 2.1f). The sciatic nerve is protected by the tagged sort rotators and capsule, and the acetabular fossa is exposed easily.

Compare the size of the femoral head to the size of the incision (the head occupies nearly the 2/3 of the incision) (Fig. 2.1f, g). Observe the size of the THA ceramic head and neck in comparison to the incision before closure (Fig. 2.1h).

 

 

 

 

Fig. 2.1 (a–h) Direct Superior Hip Approach. The pictures (a–h) depict different crucial steps of the procedure

 

c

d

 

 

 

Fig. 2.1 (continued)

 

e

f

 

 

 

Fig. 2.1 (continued)

 

g

h

 

 

 

Fig. 2.1 (continued)

 

 

Case Title: Primary Hip Arthroplasty Using Direct Anterior Approach Without a Traction Table

 

 

 

Demographics

 

Age: 74 Sex: Female BMI: 30

Relevant Past Medical History

 

Principal pathologies: Gout, HTN, HLD, and osteoporosis.

Previous surgical procedures: Bilateral TKA, total shoulder, appendectomy.

Medication: Allopurinol, furosemide, irbesar-tan, oxycodone, raloxifene.

History of presenting complaint: This 74-year-old woman has had several years of progressive right hip pain that is refractory to conservative management including NSAIDs, injections, physical therapy, and activity modification. Her

 

quality of life was severely impacted by her arthritis, and her pain is now severe and constant. She is currently dependent on a walker for ambulation.

 

Clinical Examination

 

Symptoms: Severe, constant pain localized to the groin. Exacerbated by motion and weight bearing

Range of motion: 0–100 flexion, 50/40 Abd/ Add, 20/0 ER/IR

Specific tests: Stinchfield test positive, Trendelenburg negative

Main disability: Severe pain is causing inability to ambulate without a walker

Neurovascular evaluation: Distal sensation and pulses intact

 

Preoperative Radiological

Assessment/Imaging (Figs. 2.2,

2.3, and 2.4)

 

 

 

Fig. 2.2 AP pelvis preop demonstrating severe right hip osteoarthritis

 

 

 

 

Fig. 2.3 Templated AP of the right hip preop

 

 

 

 

 

Fig. 2.4 Lateral preop

 

Preoperative Planning

 

Diagnosis: Right hip degenerative joint disease (Figs. 2.2 and 2.4).

 

Possible treatment options: Total hip arthroplasty via posterior, direct lateral, anterolateral, direct anterior with special table, or direct anterior with regular table.

Chosen treatment method: Total hip arthroplasty via direct anterior approach with a regular table.

Selection of implants if applicable and rational: A non-cemented hemispherical cup with UHMWPE liner combined with a taper-wedge titanium stem and a ceramic head were chosen.

Expected difficulties: As with all approaches to the hip joint, the direct anterior approach can present difficulties on exposure, but these can be overcome with proper technique. Potential complications include damage to the lateral femoral cutaneous nerve, bleeding and hematoma, femoral fracture, femoral nerve palsy, prolonged surgical time, and wound complications. Only LFC neurapraxia is a complication specific to the DAA.

Strategies to overcome difficulties: As with all approaches to the hip, a detailed knowledge of the vascular, neural, and muscular anatomy of the direct anterior approach is crucial to avoiding problems.

Templating: Templating was performed using built-in software of our PACs system (Fig. 2.3).

 

Surgical Note

 

Patient’s position: Supine on a regular table with the patient’s pelvis elevated on a gel bump.

Type of anesthesia: Spinal.

Surgical approach: Direct anterior.

*Main steps: The ASIS and groin crease are marked along with hash marks during preparation. An 8–10 cm incision is made approximately 2 cm lateral and distal to the ASIS. This incision should be extended as needed to improve exposure. Subcutaneous fat is cleared manually with a lap sponge. The sartorius/TFL border is identified by the red/purple appearance of the TFL lateral to the sartorius and the small perforating vessels of the TFL. The TFL fascia is incised 5 mm lateral to the sartorius border and care is taken to avoid the LFCN by minimizing medial

dissection. A blunt Hohmann retractor is placed over the superior femoral neck. A sharp Hohmann retractor is placed over the vastus lateralis and lateral femur distally in the wound. The fascia of the quadriceps is incised and a Hibbs retractor placed within the fascia to hold tension. The interval between the quadriceps and TFL is carefully dissected using a Bovie with care to identify and cauterize the ascending branches of the lateral femoral circumflex vessels. The area between the rectus femoris and vastus is cleared with a Cobb, and a blunt retractor is placed along the capsule of the inferior femoral neck. The Cobb is then used to develop the interval over the anterior acetabulum under direct visualization and in the direction of the contralateral kidney. A lighted Hohmann is placed in this interval under direct visualization. An anterior partial capsulectomy is then performed. We prefer capsulectomy because it facilitates proper exposure of the hip. The femoral neck is cut sub-capitally first and then distally to form a napkin ring of bone, which is then removed. The femoral head is removed with a corkscrew. The lateral retractor is then placed carefully under the posterior acetabulum. All bleeding is controlled (the area of the inferior capsule is carefully evaluated as it is often a source of bleeding at this stage). The acetabulum is prepped and reamed to the appropriate size, in this case for a 48 mm cup. The cup is press fit into place with the appropriate zero degree liner. Attention is then turned to the femur. The leg is placed in figure four to facilitate elevation of the femur. A lateral retractor is placed to retract the TFL. A long-tooth double-footed retractor is placed at the superior lateral greater trochanter to expose the superior capsule. A triangle of superior capsule is then removed. The double-footed retractor is then placed over the top of the greater trochanter between the trochanter and the insertion of the gluteus medius, thus minimizing the potential for damage to the gluteus medius muscle. A vertical incision in the superior capsule is then made and carried over the superior-posterior trochanter. Once done, the femur is elevated with a bone hook. The lighted anterior acetabular retractor is then removed, and a double-footed retractor is placed over the lesser trochanter.

 

Access to the femur is now accomplished by repositioning the leg (still in external rotation) into adduction with the knee fully extended. Of importance, no extension of the limb is required for full exposure of the proximal femur with this technique. An angled curette is used to sound the femoral canal, and then the femur is broached to the appropriate size component, in this case a size 6. The femoral head and neck are trialed and full stability and equal leg lengths are confirmed. This represents an important advantage of performing the surgical procedure without encumbering the leg using a special table. Small adjustments in offset and neck length can substantially improve stability and leg length with this technique, something that is not possible to assess using fluoroscopy of the hip as is done when a special table is used. The final femoral components (stem and ceramic head) are inserted and the hip is reduced. The wound is again checked for bleeding—vessels previously identified during the exposure and cauterized may resume bleeding because of the manipulations of the operation. The wound is then closed in layers with absorbable suture (monocryl in the superficial layers) and glue on the skin. A silicone-based dressing was placed.

 

Intraoperative Challenges

 

Challenges and solutions: Correct identification of the surgical interval is crucial to avoid damage to the LFCN and the femoral nerve and to avoid muscle damage by remaining within the true internervous plane. The ASIS is easily identified in most patients and is the origin of the sartorius and the anterior border of the TFL. Making the incision distal and lateral to this landmark and avoiding medial dissection minimize risk to the LFCN. For larger patients, the location of the ASIS can be confirmed after initial skin dissection by palpation through the subcutaneous fat and adjust the dissection accordingly.

 

 

Unanticipated problems and solution: An unanticipated problem that occurred postoperatively was the loosening of the acetabular compo-

 

nent (Fig. 2.5). This was addressed with a revision of the acetabular component through the direct anterior approach on a regular table (Fig. 2.6).

Thorough description of decision-making, including the reason for the final decision: The direct anterior approach can be used for revising components, and the identical setup on a regular table can be used for the revision. In this case, only the acetabular component needed revision, for which the direct anterior approach gives excellent exposure. In cases needing femoral component revision, especially those requiring ETO, an extended incision may be used that tracks posterior and lateral at the distal aspect of the standard DA incision. The acetabular bone was inspected to determine that there was NO acetabular fracture responsible for the early loosening. A larger cup with screws to augment fixation was used during the revision because the original press fit had not adequately stabilized the component.

 

 

 

 

Fig. 2.6 The cup was revised through a DA approach, and a larger cup with screws was placed

 

 

Correct identification of the TFL can be confirmed by noting the purple hue of the muscle belly and the perforating vessels that are nota-

bly absent from the medially located sartorius. Knowledge of muscular anatomy in relation to the femoral neck and capsule are key to ensure that muscles are handled carefully and not violated.

Careful retractor placement ensures the protection of muscles and nervous structures. The femoral nerve is medial to the anterior acetabulum, and care should be taken that retractors inserted over the anterior rim of the acetabulum are directed toward the opposite kidney and always placed under direct visualization. Retraction of the anterior retractor should be done carefully.

Identification and cauterization of the circumflex vessels with re-inspection prior to closure minimizes the risk of postoperative hematoma.

During exposure of the femur, it is important to release the superior and superomedial capsule to allow elevation of the femur out of the wound. The positioning of the leg in figure four helps with exposure of the superior capsule for excision. As the femur is elevated, further release of the superior and posterior capsule can be performed as needed. To complete elevation of the femur, a double-footed retractor is placed over the greater trochanter, while the entire thigh and leg are externally rotated and adducted with the knee straight.

Intraoperative fracture of the femur is prevented by inserting the femoral component by hand (no attached mechanical inserter) and then impacted into place using a gentle force directed distally and laterally.

After placement of components, the wound should again be thoroughly checked for bleeding before closure.

We recommend closure with absorbable suture and subcutaneous skin suture with skin glue and a silicon base dressing to help prevent wound complications. This dressing is kept in place for 1 week to limit external contamination of the wound.

Postoperative Radiographs 2.3.9 Postoperative Management

 

 

 

Chemoprophylaxis and anticoagulant treatment period: ASA 81 mg for 1 month

Gait/limb loading until full loading: WBAT, no restrictions, even after the revision surgery

 

1.  

Follow-Up and Complications

 

The acetabular cup came loose postoperatively. This was treated with revision to a larger cup with screws through a DA approach.

 

Discussion [18, 35, 42, 43]

 

 

Fig. 2.5 Postoperatively, the cup came loose

Advantages of the applied method: The DA approach in an internervous plane with minimal muscle disruption. It can be performed on a regular table with the patient supine so that stability and leg length can be easily checked. For the vast

 

majority of patients, a porous-coated acetabular component can be placed without screws. Screws can be used at the discretion of the surgeon to supplement fixation but should not be relied upon for primary fixation of the component. Screws may put neurovascular and pelvic structures at risk, and as such, they should be used judiciously in primary total hip surgery only when supplemental fixation is required [43].

Disadvantages of the method: The lateral femoral cutaneous nerve is at risk if the approach is not performed correctly. As for all approaches, the femoral and sciatic nerve is at risk as well.

Alternative evidence-based techniques for the case: There are multiple papers describing alternative approaches for total hip arthroplasty.

Why is the chosen technique better for this case? The senior author is very experienced in direct anterior approach and can perform the operation efficiently with minimal complications.

Indications and contraindications for your technique: Indications are the need for a total hip replacement. There are no strict contraindications.

Learning curve and how to manage complications: The learning curve for this approach is estimated to be 40–100 cases.

Level of evidence concerning the superiority of this method against others: Level IV.