Orthopedic Teaching Cases 2023, Jan, 16 | 12:00 am

Surgery of the Shoulder

 

 

Diagnostic shoulder arthroscopy

 

85

 

Shoulder arthroplasty

 

108

Arthroscopic procedures

90

Viva questions

112

Open shoulder procedures

98

 

 

 

Since the publication of the first edition of this book, arthroscopic shoulder surgery has seen a significant expansion and consequentially open procedures have become increasingly less common. Thankfully, the principles behind the various procedures have stayed the same. Similarly, several large and well-published randomised controlled trials have questioned the efficacy of commonly used procedures and the practice of many surgeons is changing as a result.

We describe the process of a diagnostic shoulder arthroscopy and then expand on how therapeutic procedures are performed, describing open alternatives. We also discuss the treatment of degenerative joint disease with arthroplasty.

 

Diagnostic shoulder arthroscopy‌

Diagnostic shoulder arthroscopy can be used as part of arthroscopic treatment of various pathologies, but also purely for diagnostic purposes given the relatively low complication rates.

Contraindications are few and only really include

 

  • Infection of overlying skin

  • Lack of proper arthroscopic instrumentation

     

    Complication rates are as mentioned very low, but informed consent of all the possible risks should be discussed with patients. These include

  • Nerve injury: The musculocutaneous nerve (anterior portal) and the axillary nerve (lateral portal) are most at risk. The suprascapular nerve can be damaged by the inexperienced arthroscopist.

  • Chondral or labral injuries: Relatively uncommon.

     

  • Fluid imbalance due to fluid extravasation.

  • Infection: Very rare.

  • Vascular injury: Very rare.

     

    Operative planning

    Recent radiographs and when relevant, ultrasound, computed tomography (CT) and magnetic resonance (MR) images (with or without arthrograms), should be available. Although only basic equipment is necessary for a diagnostic procedure, standard equipment should be available so that therapeutic treatment can be undertaken if necessary. This includes

  • Camera with imaging and recording equipment

  • Xenon light source

  • Fluid management system (pump set at 30–70 mm Hg)

  • 5 mm 30° (±70°) scopes with high-flow sleeve

  • Shaver

  • Burr

  • Vaporiser

  • Arthroscopic instruments

  • Cannulas

  • Arthroscopic implants

     

    Anaesthesia and positioning

    General anaesthesia is preferred with the use of an interscalene block if certain procedures are planned. The use of a block alone is possible; however, the posterior portal is often not covered as the upper thoracic nerve roots innervate the corresponding area. A ‘top up’ of local anaesthetic to the surrounding tissues may be required.

    Two options for patient positioning exist: lateral and beach chair. The choice is very much surgeon dependent.

     

  • If the lateral position is used, the patient should be as far back towards the edge of the table as possible, with 15° of posterior tilt (horizontal glenoid). Front and back supports are required to secure the patient. The patient’s head is placed in a gel ring. Four kilograms of longitudinal skin traction is applied with the arm in 30°–50° abduction and 20°–30° forward flexion (Figure 6.1). The brachial plexus should be palpated to ensure that it remains soft and that excessive traction is not being applied.

  • If the beach chair position is used, the appropriate operating table (with removable lateral corner) is required. Prior to raising the table into the beach chair position, the table should be tilted into a Trendelenburg position to prevent the patient sliding down the table. A pillow should also be used under the knees. Traction can be added based on surgeon preference. This approach is helpful if progressing to an open procedure.

    The surgical field is prepared with a germicidal solution, and waterproof drapes are used with adhesive edges to provide a seal to the skin.

     

     

     

    Traction

     

     

     

     

    Landmarks

    Figure 6.1 Positioning and traction for shoulder arthroscopy.

    It is very important to identify and draw on the landmarks of the shoulder, particularly given the difficulty in identifying them once it has swollen with fluid. These landmarks should include

  • Spine of the scapula.

  • Acromion – the posterolateral corner, lateral acromion, and anterolateral corners.

  • Supraclavicular fossa.

  • Distal clavicle and acromioclavicular joint (ACJ).

  • Tip of the coracoid.

  • A line from the anterolateral corner of the acromion heading towards the upper arm signifies the position of the long head of the biceps tendon.

  • Lateral orientation line, which aids in the placement of a lateral portal.

     

    Portals

    The accurate placement of arthroscopic portals is essential in shoulder arthroscopy. A variety of portals can be used.

     

    Posterior portal

    This is the most common viewing portal. A stab incision to the skin is placed 2 cm medial and 2 cm inferior to the posterolateral corner of the acromion. This correlates to a palpable soft spot, which denotes the plane between the infraspinatus and teres minor.

    To access the glenohumeral joint, a trocar is aimed inferomedially towards the tip of the coracoid. The glenoid rim and the humeral head can be palpated and the trocar can be

     

    pushed between them. Balottement of the humeral head posteriorly or first infiltrating the glenohumeral joint with saline could aid in the placement of the trocar. A popping sensation is usually felt as the joint is entered. The introducer of the trocar is removed and the camera inserted. Normal saline is then attached and the joint irrigated.

    To enter the subacromial space, the same posterior portal skin incision is used; however, the scope is aimed superolaterally towards the anterolateral corner of the acromion. The scope must enter the bursa and show the acromion and the bursal aspect of the cuff clearly. If cobweb-like tissue is seen, then the scope is outside the bursa and should be repositioned. This is important as the bursa helps to contain the irrigation fluid, thus limiting soft tissue swelling around the shoulder.

     

    Anterior portal

    Once the posterior portal is established, all other portals are made using an outside-in technique in which a spinal needle is used to determine the exact location and angle of entry into the joint. A standard low anterior portal is placed above the lateral half of the subscapularis but medial to the medial biceps pulley. Once the needle has been placed in the appropriate position the portal is made using a size 11 scalpel, which is inserted in the same direction as the needle taking care to avoid the long head of the biceps (LHB), conjoint tendon and rotator cuff.

     

    Superolateral portal

    This portal provides access to both the biceps tendon and the labrum anteriorly. It is placed around 1 cm lateral to the anterolateral edge of the acromion and is used for suture management and anchor placement during subscapularis and anterior labral repairs.

     

    Lateral portal

    The lateral portal is 5 cm (three fingers breadth) distal to the acromion and 1 cm anterior to the mid-lateral line (in line with the posterior line of the ACJ). This portal is used for instrumentation of the subacromial space (Figure 6.2) during subacromial decompressions and rotator cuff repairs.

     

    Accessory portals

    Other portals can be made on demand. These include the anterosuperolateral, accessory anterior, accessory lateral, accessory posterior, port of Wilmington and Neviaser (superior) portals. A cannula may be used if proceeding to a therapeutic procedure. Clear cannulas are recommended as they allow visualisation and aid in suture management.

     

    Procedure

    A systematic approach to evaluation of the shoulder is imperative so that pathologies are not missed. With the scope in the posterior portal, the glenohumeral joint is assessed first. By using the LHB tendon as a reference, the camera is adjusted so that the image is shown in the correct superoinferior plane. The authors recommend the following systematic way of assessing the shoulder:

     

     

    Lateral portal

    2 cm

    2 cm

    Anterior

    portal

    Posterior portal

     

     

     

    Figure 6.2 Common arthroscopic portals.

     

  • The LHB should first be assessed at its insertion at the superior glenoid tubercle. By raising the arm in 90° abduction and 90° external rotation, the presence of a SLAP (superior labrum from anterior to posterior) tear can be assessed as the labrum rolls off the glenoid rim (peel-back sign). The scope can then be turned laterally and the intra-articular portion of the LHB, and that portion of the biceps tendon that lies within the inter-tubercular grove, can be assessed.

  • The stability of the LHB can then be visualised by internally and externally rotating the shoulder. The medial sling/pulley can then be inspected before examining the

    subscapularis tendon, superior glenohumeral ligament and rotator interval in more detail. The subscapularis tendon insertion can be best visualised with the arm in internal rotation.

  • By gently withdrawing the scope and looking laterally, the posterior pulley of the LHB can be viewed and then the supraspinatus and infraspinatus tendons can be examined. The bare area and any Hill-Sachs lesions can now be identified.

  • As the arthroscope is taken further inferiorly it enters the inferior recess. The reflection of the inferior capsule and the posterior band of the inferior glenohumeral ligament (hammock effect) can be seen. By then rotating the scope, the posterior inferior labrum can be visualised and then the entire posterior and superior labrum examined before assessing the chondral surfaces of both the humeral head and glenoid.

  • The anterior stabilising structures can now be examined. Superiorly the sublabral foramen, labrum and middle glenohumeral and anterior band of the inferior glenohumeral ligaments can all be visualised.

     

  • An anterior portal can be made through the rotator interval for the introduction of a probe for further assessment of any soft tissue pathology or if any glenoid bone loss needs to be further assessed.

  • The subacromial space should then be examined by repositioning the trocar above the rotator cuff. Superiorly the acromion is seen, anteriorly the coracoacromial ligament and inferiorly the bursal side of the rotator cuff. The presence of bursal side rotator cuff tears, impingement lesions and acromial and ACJ pathology can all be assessed.

This is just one example of a systematic assessment of arthroscopic shoulder anatomy. Each surgeon can develop their own system; however, it is essential that all surgeons are familiar with arthroscopic anatomy and normal variations.

 

Closure and postoperative care

Wounds can be closed with suture or Steri-Strips or left open. A pressure dressing assists with a swollen joint. If the procedure was purely diagnostic, a sling is only necessary for comfort and to assist with weakness while a block wears off.

 

Arthroscopic procedures‌

Subacromial decompression

Over the last decade, arthroscopic subacromial decompressions (ASDs) have superseded open acromioplasty, and their use has increased exponentially. Recent notable publications have questioned this overuse. Symptoms of impingement are often associated with an underlying diagnosis, be it instability, rotator cuff pathology, biceps tendonitis, etc. We must ensure ASDs are performed in the correct patient groups.

 

Recommended reference

Beard DJ, Rees JL, Cook JA et al.; CSAW Study Group. Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): A multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial. Lancet. 2018;391(10118):329–338.

 

Risks

In addition to those described in the diagnostic arthroscopy section, patients should be warned of acromial fracture, as well as ongoing and recurrence of symptoms.

 

Procedure

Imaging should be interrogated for underlying pathology. In particular, radiographs should be assessed to ensure an os acromiale is not present. The arthroscopic pump is set between 30 and 70 mm Hg. The arthroscope is introduced through the posterior portal and a diagnostic arthroscopy performed. It is then introduced into the subacromial bursa. The bursal surface of the cuff is inspected to confirm the presence of an impingement lesion (inflammation, roughening and fibrillation). Next, the undersurface of the acromion is examined for a corresponding ‘kissing’ lesion. The acromion can be further assessed using an arthroscopic probe for any acromial hooks or spurs. The coracoacromial ligament is

 

also inspected. The lateral portal is used for instrumentation. A spinal needle is used for the outside-in technique of portal placement. Although this portal is at the level of the axillary nerve, the nerve is not usually threatened as the instruments are aimed proximally towards the acromion. No cannula is required.

A successful decompression has three main components:

 

  1. Resection of the bursa

  2. Release of coracoacromial ligament

  3. Burring of the acromion

 

Soft tissue resection and haemostasis can be performed with an electrocautery probe/ vaporiser. The soft tissue on the undersurface of the acromion is then resected and the coracoacromial ligament detached. Radial cuts can be made to ensure the ligament does not reform, but care must be taken not to damage the branches of the thoracoacromial artery. The lateral edge of the acromion must be exposed to ensure adequate lateral decompression.

A barrel burr/shaver is used for bone resection. If the acromion has a lateral down-slope then a lateral bevel is performed. The decompression is then performed by excising the anterior acromion, from lateral to medial. The acromial branch of the coracoacromial vessel is at risk at this stage also. Anterior resection is usually approximately 4 mm (the width of the burr) or until the anterior deltoid attachment is reached. Medially, the resection is limited by the ACJ. The undersurface of the acromion is then chamfered, to smooth out any ridges (Figure 6.3).

 

 

Lateral excision and chamfer

 

Anterior excision

 

CA ligament

excised

 

 

 

Figure 6.3 Arthroscopic subacromial decompression; CA, coracoacromial.

 

Further refinement of the acromioplasty can be performed by placing the arthroscope in the lateral portal and the shaver posteriorly. Any residual bone can be resected using the posterior acromion as a ‘cutting block’, thus creating a flat undersurface to the acromion.

Wounds can be closed as per a diagnostic arthroscopy. No postoperative restrictions are required, and rehabilitation can be commenced immediately.

 

Acromioclavicular joint excision

ACJ excision can be performed arthroscopically for symptomatic ACJ arthritis which has failed conservative treatment. Stability of the joint is maintained through preservation of the superior ACJ ligaments.

 

Risks

Risks are much the same as a subacromial decompression with the added possible complication of joint instability. Of all the arthroscopic shoulder procedures, ACJ excision is possibly the most painful postoperatively and patients should be warned accordingly.

 

Procedure

Essentially, a subacromial decompression is performed; however, the anterior portal should be made in line with the orientation of the ACJ, which occasionally places it slightly more laterally. Accurate placement can be performed via an outside-in technique, ensuring the needle is parallel to the joint line. Identifying the joint is aided through placing a needle through the joint and by palpating the lateral end of the clavicle. A shaver or vaporiser can be used through the lateral portal to expose the ACJ. Scar tissue and the remnants of the meniscus are resected and any inferior osteophytes excised. To ensure adequate visualisation of the ACJ the fibrofatty tissue in the region of the scapular spine and distal clavicle should be resected.

A barrel burr is used to excise the distal clavicle from inferior to superior and from lateral to medial. To ensure that adequate bone is resected, especially posteriorly, the entire circumference of the resected distal clavicle must be visualised. This is often only achieved if both the anterior and posterior acromioclavicular ligaments are excised. However, care must be taken not to excise the superior acromioclavicular ligament or to resect too much bone as this can destabilise the joint. The aim is for approximately 10 mm of bone resection from the medial acromial facet to the distal clavicle, which can be assessed by measuring against the width of the shaver. Occasionally, a Neviaser portal is required to complete the resection.

Wounds can be closed as per a diagnostic arthroscopy. No postoperative restrictions are required, and rehabilitation can be commenced immediately.

 

Recommended reference

Flatow EL, Duralde XA, Nicholson GP et al. Arthroscopic resection of the distal clavicle with a superior approach. J Shoulder Elbow Surg. 1995;4:41–50.

Biceps tenotomy/tenodesis

The LHB is often a cause of pain as it degenerates. If its pulley is damaged it may also sublux in the joint providing difficulty identifying the relevant structures, and possibly ‘cheese-wire’ through the superior subscapularis. In symptomatic patients, the LHB may be either tenotomised or tenodesed with no clear evidence either way, but a tenodesis being preferred in the younger and active patient. Other indications for interventions include partial thickness tears or SLAP tears. Options for a tenodesis include mini-open

 

approaches, tenodesing the screw in the bicipital groove, and subpectoral tenodesis, some of which can be performed arthroscopically.

 

Risks

Once again, all the risks of an ASD must be relayed to the patient. In addition, patients who have a tenotomy may develop a ‘Popeye sign’ or weakness of the biceps. Morbidity is associated with a tenodesis, and this includes ‘biceps groove’ pain, particularly when a tenodesis screw is used, fracture or re-rupture.

 

Procedure

During an arthroscopy, an anterior portal is created. A knife or vaporiser may be used to directly divide the LHB under vision. Care must be taken not to damage the superior labrum and the overlying supraspinatus tendon. Some advocate taking a large soft tissue sleeve which gets trapped in the biceps tunnel, creating a ‘soft tissue tenodesis’. Alternatively, once a tenotomy has been performed, a mini-open approach may be used to tenodese the remnant biceps tendon to the humerus using an endo-button or an interference screw.

Postoperative management is the same as for a decompression; however, patients who have a tenodesis should avoid resisted biceps activities for up to 6 weeks.

 

Recommended reference

Moon SC, Cho NS, Rhee YG. Analysis of “hidden lesions” of the extra-articular biceps after subpectoral biceps tenodesis: the subpectoral portion as the optimal tenodesis site. Am J Sports Med. 2015 Jan;43(1):63–68.

 

Rotator cuff repair

Despite large trials showing no difference in outcomes between mini-open and arthroscopic rotator cuff repairs, the latter has become increasingly popular. Techniques and experience have improved such that even massive and retracted cuff tears can be repaired arthroscopically. Indications include

  • Shoulder pain, including night pain on a background of a chronic tear

  • Loss of function or quality of life

  • Traumatic rotator cuff tear

  • Failure of conservative management of a chronic rotator cuff tear

     

    Many options exist to treat cuff tears, including anterior deltoid strengthening alone, suprascapular nerve ablation, partial cuff repair, superior capsular reconstruction and even a reverse polarity joint replacement. Patient age, expectations and severity of the tear should all be taken into account when making a decision on how to proceed.

     

    Risks

    In addition to the previously mentioned, patients should be warned of damage to nerves (e.g. axillary or suprascapular), stiffness, reduced range of movement, failure of the repair, re-rupture and continued weakness.

     

    Procedure

    Posterior, anterior, lateral and accessory lateral portals are often required. The superior Neviaser portal can be useful for passing sutures through the cuff, particularly in massive tears. Glenohumeral arthroscopy is performed and any concurrent pathology assessed and treated as necessary. The cuff is then assessed with respect to its size, shape and mobility. The arthroscope is inserted into the subacromial space and a subacromial decompression (with or without ACJ excision) is performed as necessary. Any releases are then undertaken and the footprint is prepared with the vaporiser and burr, so the exposed bone bleeds, helping the rotator cuff to heal.

    Various techniques are described for tendon fixation. The type of anchor and whether a single- or double-row fixation is used remains debatable. However, the principle is to have a large contact area between the tendon and the bone to encourage healing. To achieve this a variety of arthroscopic instruments are required. The suture anchor is inserted percutaneously or through the superolateral portal, such that the correct bone entry angle is achieved. During anchor placement the choice of viewing portal is often determined by the size of the tear with small or partial tears requiring an intra-articular camera position and larger tears requiring visualisation from the subacromial space. The sutures can now be passed using antegrade techniques, using suture passers, or with retrograde techniques where penetrators or suture shuttling instruments are used. When passing sutures, a posterior or lateral viewing portal is used depending on the size and location of the tear.

    Sutures are placed approximately 1 cm apart. Suture management is critical in rotator cuff repairs as it is easy to confuse or tangle the sutures. To avoid difficulties only two sutures should be used per portal and if a cannula is not used then sutures must be passed through the same portal together to avoid interposing soft tissue when tying knots. Knot tying is done under direct vision in the subacromial space. Alternatively, knotless techniques may be employed.

    For large and massive tears, side-to-side convergence sutures can be used to reduce the size of the tear (Figure 6.4). Retracted tears can be mobilised using interval slides. The final construct can be viewed from both the subacromial space and the glenohumeral joint to ensure footprint reconstruction.

    Closures of cannula portals are more likely to require sutures. The postoperative regimen depends on the size of the tear, and of course surgeon preference.

     

  • Small and medium tears

    • Sling for 6 weeks

    • Passive/active assisted exercises to 30° external rotation (if no subscapularis tear) and elevation to 90° for first 6 weeks

    • Passive overhead elevation at 6 weeks with further increase in external rotation as able

    • Active exercises once range is normal and strengthening at 12 weeks

  • Large/massive tears

    • Immobilise in sling (with or without abduction pillow) sling for 6 weeks

    • Passive/active assisted exercises – elevation to 90° and external rotation to 0° in the presence of a subscapularis repair, otherwise 30° for first 6 weeks

       

       

      Original tear size

       

      Side-to-side sutures reduces size of tear

       

       

       

      Figure 6.4 Side-to-side sutures used to reduce the size of a rotator cuff tear.

    • Passive overhead elevation at 6 weeks with further increase in external rotation as able

    • Active exercises at 12 weeks and strengthening at 16 weeks

      Arthroscopic soft tissue repair for instability

      The glenohumeral joint is the most likely joint to dislocate and recent evidence has moved many units to offering earlier surgical intervention with a view to prevent recurrent dislocations and maintain bone stock. Of all the types of shoulder instability, acute traumatic anterior dislocations fare best with surgical intervention, and multidirectional atraumatic fare the worst. In cases of significant bone loss, bony procedures are generally most suitable.

      Risks

      Patients should be consented for recurrence, stiffness, early arthritis, neurovascular injury and cuff pathology, particularly in posterior repairs.

      Procedure

      Prior to commencing the operation, shoulder stability should be assessed with an examination under anaesthesia. The humeral head is translated anteriorly and posteriorly, the direction noted and its excursion graded and documented:

  • 1 – Minimal

  • 2 – To the edge of the labrum

  • 3 – Dislocates

A standard posterior viewing portal is used to assess the labral and capsular pathology. Using an outside-in technique, an anterosuperolateral portal is placed at the junction of the anterior border of the supraspinatus tendon and the upper rotator interval. It should allow a 45° angle of approach to the superior labrum. This will provide both an anterior viewing portal and an accessory portal for SLAP repairs or for suture management.

 

A further anterior portal is placed just above the subscapularis tendon for anterior repairs and in posterior repairs, a Wilmington portal should be created with a longitudinal split in the infraspinatus tendon. Both are placed such that the angle of approach allows accurate suture anchor placement. This can be best assessed using the anterosuperior viewing portal. A clear cannula is recommended for better visualisation.

The degree of tissue separation and amount of capsular laxity are assessed. The drive-through sign is noted. This reflects the ease with which the scope is passed between the humeral head and the glenoid and is a sign of significant laxity. Whether anterior or posterior, the Bankart lesion (i.e. detached labrum) is released all the way down to the 6 o’clock position on the glenoid with sharp elevators. A sufficient release is confirmed by grabbing the inferior tissue with a manipulator and elevating it superiorly against the glenoid rim. The anterior or posterior glenoid is decorticated with a rasp and burr or shaver (ensure that suction is clamped during this stage).

Anchors are then sequentially placed, starting from an inferior position. Anteriorly the first should be at the 5 o’clock position on the glenoid rim and posteriorly at the 7 o’clock position. A suture is passed through the tissue inferiorly using a penetrator or suture shuttle technique. The amount of tissue included in the suture is critical, as it will dictate the degree of stability following the repair. To help reduce the labral tissue back to the glenoid rim the knot can be tied with the arm in flexion and internal rotation for anterior repairs and abduction and external rotation for posterior repairs. Capsular plication (weaving of sutures through the capsule) can also be performed in cases of marked capsular laxity. Further anchors are placed at 4 and 3 o’clock positions anteriorly or 8 and 9 o’clock positions posteriorly to approximate the labrum and perform a distal to proximal shift of the capsule (Figure 6.5). Anterior repairs should aim for a south to north shift to prevent over-tightening of the shoulder.

 

 

Biceps

Direction of shift

Anchors

PIGHL

AIGHL

 

 

 

Figure 6.5 Capsulolabral reconstruction with anterior inferior glenohumeral ligament reconstruction (AIGHL). PIGHL, posterior IGHL.

 

Postoperatively, patients should be placed in a poly sling or brace. These should aim to prevent external rotation in anterior repairs and internal rotation in posterior repairs. Often if the repair is not in too much tension, a body belt or external rotation brace can be avoided. Pendulum exercises can start in the first week, progressing to active rotation after 4 weeks, depending on surgeon and physiotherapy preferences.

 

Capsular release

Adhesive capsulitis is a common and debilitating pathology. Lots of interest has developed as to the merits of surgical release rather than physiotherapy and hydrodilation alone. While it is generally a self-limiting pathology, the desire to return to function faster with an increased residual range of movement is a relative indication. Care should be taken to rule out the other two main causes of a lack of external glenohumeral rotation: shoulder osteoarthritis and a locked posterior dislocation.

 

Risks

Capsular releases require a large amount of tissue dissection so the risk of damage to the intra-articular structures and surrounding nerves increases. A manipulation under anaesthesia risks fracturing the proximal humerus.

 

Procedure

Preoperative range of movement should be assessed by locking the scapula through palpation of the acromion and coracoid process. Standard anterior and posterior viewing portals are created, which can be particularly difficult given the thickened and fibrosed capsule.

Once inside the joint, a shaver, burr and capsular punch can all be used to excise the fibrosed capsule. The majority of work is performed anteriorly by taking down the rotator interval, to the conjoint tendon, coracoid process and anterior deltoid. The LHB may be tethered in scar tissue and if so should be freed. If this does not suffice, the superior, posterior or inferior capsule may be excised. Once finished, the shoulder should be manipulated using a short lever arm to prevent fracture. Once the patient has had their wounds closed and a pressure dressing applied, elevation in a Bradford sling helps to maintain mobility. Demonstrating the increased range of movement to a patient prior to the block wearing off often helps with the rehabilitation.

Postoperative physiotherapy should commence as soon as possible. Patients should be warned that approximately half of the obtained range of movement would remain long term.

 

Recommended reference

Brealey S, Armstrong AL, Brooksbank A et al. United Kingdom Frozen Shoulder Trial (UK FROST), multi-centre, randomised, 12 month, parallel group, superiority study to compare the clinical and cost-effectiveness of Early Structured Physiotherapy versus manipulation under anaesthesia versus arthroscopic capsular release for patients referred to secondary care with a primary frozen shoulder: Study protocol for a randomised controlled trial. Trials. 2017;18:614.

 

Open shoulder procedures‌

Many of the now performed arthroscopic procedures were for many years successfully performed utilising open techniques. While arthroscopic procedures are less invasive and traumatic, they remain difficult to master. Knowledge of their limitations is important, as are their ‘bail-out’ options, most of which are open techniques. In this section of the chapter, we describe the principles of open techniques of the aforementioned procedures.

 

Acromioplasty

The principles are much the same as arthroscopic. In cases of significant cuff tears, acromioplastyshouldbeavoidedaslossof theanteriorstructuresmayleadto anterosuperior escape of the humeral head.

 

Risks

Risks include

  • Infection

  • Neurovascular injury

  • Stiffness

  • Fracture of the acromion: Can occur if the osteotomy is performed in the wrong plane or if excess bone is resected

  • Detachment of the deltoid

  • Failure of procedure: Wrong indications, incomplete decompression, missed cuff tear

    Procedure

    Anaesthesia is usually general, regional or combined. Where general anaesthesia is used alone, local anaesthetic is recommended for pain relief. The patient is in the beach chair position. A small sandbag is put under the operated shoulder. An arm board can be attached to the side of the table to rest the arm on. The surgical field is prepared and adequately draped.

    Landmarks include the

     

  • Acromioclavicular joint

  • Anterolateral corner of acromion

  • Tip of the coracoid

     

    This procedure is rarely performed as an isolated open procedure as it is most commonly performed arthroscopically or in association with a larger open procedure. As such, the skin incision will be dictated by the other procedure; however, if it is to be performed as an isolated open procedure, a 2–3 cm anterosuperior incision is made over the anterior acromion. The incision is continued through subcutaneous fat and down to the deltoid fascia. The anterior deltoid raphe is split in the line of its fibres. The anterior acromion is located and then an osteoperiosteal flap raised such that a strong deltoid repair can be performed at the end of the procedure.

    Deep to the anterolateral tip of the acromion is the coracoacromial ligament. A swab can be used to sweep the soft tissue medially further exposing the ligament and separating

     

    its medial border from the clavipectoral fascia. An oscillating saw is used to excise the anteroinferior acromion. The osteotomy is aimed so that it is in continuation with the undersurface of the acromion (Figure 6.6). The bony fragment, with its attached coracoacromial ligament, is excised. Traction is applied to the patient’s arm and the undersurface of the acromion is smoothed using bone nibblers. The underlying rotator cuff should then be examined for any associated pathology.

     

     

     

     

    Figure 6.6 The correct orientation for the acromion osteotomy.

     

    A good deltoid reconstruction is essential. If the quality of the osteoperiosteal flaps is poor, a transosseous repair using number 2 Ethibond is performed followed by subcutaneous 2/0 Vicryl and 3/0 Monocryl to skin.

     

    Postoperative care and instructions

    Passive-/active-assisted exercises are started from day 1 – 90° forward elevation and 30° external rotation for 3 weeks increasing to full range by 6 weeks. Strengthening exercises can be started at 6 weeks and repetitive overhead exercises at 3 months.

     

    Acromioclavicular joint (ACJ) excision

    Open ACJ excisions are indicated as revision procedures or when the orientation of an ACJ precludes arthroscopic resection.

     

    Procedure

    If performed in combination with an open acromioplasty, the same approach as previously described is made, although the incision and subsequent dissection will need to be extended medially. If performed in isolation, a 2–3 cm strap incision is made over the distal clavicle and then a transverse incision is made in the deltotrapezoidal fascia to expose the ACJ.

    Retractors are placed to expose the distal clavicle and then an oscillating saw is used to resect enough distal clavicle such that there is a 10 mm gap between the medial acromion and the resected distal clavicle (Figure 6.7). Care must be taken not to resect too much distal clavicle otherwise distal clavicular instability can occur. Any osteophytes on the undersurface of the acromion are trimmed with bone nibblers and any residual meniscus removed.

     

     

     

    1 cm

     

     

     

    Figure 6.7 Excision of the acromioclavicular joint.

     

    The superior acromioclavicular ligament and deltotrapezoidal fascia are then repaired. If performed in association with an acromioplasty, the deltoid is repaired in the manner already discussed.

     

    Rotator cuff repair

    Open cuff repairs are often considered if the tear is large and retracted, or when used in combination with other procedures. It is imperative to understand the principles of open surgery for the cases where arthroscopy is not possible. Preoperative planning and consent are much the same as in open procedures, although there is a greater risk of neurovascular injury.

     

    Procedure

    The patient is essentially set up the same as for an arthroscopic procedure. The important landmarks are

  • Acromioclavicular joint

  • Anterolateral and posterolateral corners of acromion

  • Tip of coracoid

     

    The patient is in the beach chair position. A small sandbag is put under the shoulder. An arm board can be attached to the side of the table to rest the arm on. The surgical field is prepared and adequately draped.

     

    Structure at risk

    The axillary nerve is approximately 5 cm distal to the lateral acromion and therefore the inferior limit of any incision must not extend beyond this point. This position corresponds to the lower limit of the inferior reflection of the subdeltoid bursa.

     

     

    An anterosuperior approach is used. An 8 cm incision is made just posterior to the anterior aspect of the ACJ andis directedtowards theanterolateralcorner of theacromionanddownthe anterior deltoid raphe. A smaller incision can be performed if an arthroscopic decompression has already been performed such that a mini-open procedure can be undertaken.

    The deltoid is bluntly split at the anterior raphe (junction of the anterior and middle thirds). The deltoid is detached off the anterior acromion with an osteoperiosteal sleeve. The bursa

     

    is split longitudinally. The inferior reflection of the bursa denotes the position of the axillary nerve, which can be palpated and avoided thereafter (Figure 6.8). The coracoacromial ligament is detached from the undersurface of the acromion.

     

     

     

    Axillary nerve

     

    Inferior reflection of subdeltoid bursa

     

     

    Figure 6.8 The relationship of the subdeltoid bursa to the axillary nerve.

     

     

    Anterior acromioplasty (with or without ACJ excision) can be carried out as required. The size of the tear is measured and traction sutures are placed through the cuff. The cuff is then mobilised sequentially, initially with blunt dissection; however, a sharp release of the superior capsule and the coracohumeral ligament may be necessary. In massive retracted tears anterior and posterior interval slides may also be necessary. These can also be performed arthroscopically such that only a mini-open approach need be adopted. The configuration and tension of the mobilised cuff tear are then assessed in order to plan the repair. A shallow bony trough/footprint is prepared using an osteotome (or burr in a mini-open) at the level of tendon insertion. This should be made just lateral to the articular surface. The method of the tendon repair is determined by the operating surgeon. Single- and double-row anchor repairs can be undertaken depending on the size of the tear or alternatively a transosseous suture repair can be performed. In the latter method the tendon is repaired with a number 2 Ethibond Mason Allen suture. In each method the aim is to achieve healing of the tendon to the footprint.

    A good deltoid reconstruction is essential. If the quality of the osteoperiosteal flaps is poor a transosseous deltoid repair, using number 2 Ethibond, is performed. The deltoid raphe should be closed with 2/0 Vicryl and then 2/0 Vicryl for closure of the subcutaneous tissues and 3/0 Monocryl to skin.

     

    Acromioclavicular joint reconstruction

    ACJ disruptions are being increasingly treated non-operatively in line with recent literature, with Rockwood grade III and IV disruptions not necessarily requiring acute surgery. If the

     

    disruption becomes symptomatic at a later date, the ACJ can be reconstructed. There are several options for reconstruction, using either allograft, autograft or synthetic materials. These can be used in the modified Weaver-Dunn (described later), a LARS ligament, Tightrope or a Lockdown procedure. Using autografts or allografts should be avoided where the donor tendon has the potential towards hyperlaxity. Describing all procedures is outside the remit of this chapter. Instead we discuss the modified Weaver-Dunn procedure, as it is popular with the authors.

     

    Risks

    Infection, neurovascular injury, stiffness and recurrent instability are all possible. Postoperative rehabilitation protocols tend to be demanding so the correct patient should be selected for surgery.

     

    Procedure

    Anaesthesia is usually general, regional or combined. Where general anaesthesia is used alone, local anaesthetic is recommended for postoperative pain relief.

    The patient is placed in the beach chair position. A small sandbag is put under the shoulder. An arm board can be attached to the side of the table to rest the arm on. The surgical field is prepared and adequately draped. Landmarks include the

  • ACJ

  • Anterolateral corner of the acromion

  • Tip of coracoid

     

    The technique will vary depending on whether an acute or chronic injury is being addressed. Acute injuries do not require a ligament transfer procedure as part of the reconstruction. Chronic injuries are best managed with a biological reconstruction, which is supplemented by another fixation device until healing has occurred approximately 3 months after repair. A strap incision is made, 1 cm medial to the ACJ, and extending down to the coracoid.

    The deltotrapezoidal fascia is incised longitudinally along the distal clavicle with an extension across the superior acromioclavicular capsule/ligament and further laterally over the anterior acromion. The deltoid fibres are elevated off the clavicle and, at the acromion, an osteoperiosteal flap is raised to aid later repair. The coracoacromial ligament is defined by sweeping bluntly laterally with a swab. It is then detached from the acromion with a sliver of bone. It is then mobilised down to the coracoid and a whipstitch applied to the ligament with number 2 Ethibond. The distal 1 cm of the clavicle is excised obliquely with an oscillating saw. The bone fragment is retained for later autologous bone graft.

    The clavicle is reduced to its anatomical position by reducing the arm back up to the clavicle and by further reducing the clavicle downwards and forwards. This position must be maintained prior to the ligament transfer. This can be achieved by a number of techniques, including a Bosworth screw, three strands of PDS cord (Johnson & Johnson) looped around the coracoid and clavicle or, with a TightRope reconstruction device (Arthrex Inc; Naples, Florida).

     

    Once held in the reduced position two 2 mm drill holes are then made in the superior cortex of the clavicle. The bony fragment of the acromioclavicular ligament is passed into the intramedullary canal and the two sutures are passed through the holes, tensioned and tied (Figure 6.9). An autograft from the resected distal clavicle is then used to graft any redundant space around the transferred ligament.

     

     

     

     

     

    Figure 6.9 Acromioclavicular joint reconstruction.

     

    In acute cases (<3–4 weeks after injury) the coracoclavicular ligaments and superior acromioclavicular capsule/ligament can be repaired and then supplemented with one of the stabilising techniques described earlier. A Weaver-Dunn ligament transfer is not required.

    A good deltotrapezoidal reconstruction is essential. If the quality of the anterior acromial osteoperiosteal flap is poor, a transosseous repair using number 2 Ethibond is performed and in cases with significant superior migration of the clavicle any redundant deltotrapezoidal fascia can undergo a ‘double-breasted’ repair with 1 Vicryl adding further superior support to the reconstruction; 2/0 Vicryl is used for closure of the subcutaneous tissues and 3/0 Monocryl is used for skin.

    Postoperative regimens should include

     

  • Six weeks in a sling with passive, and active assisted, forward elevation to 90° and external rotation to 30°

  • Progress to active shoulder movement, below shoulder height, from 6 weeks with passive stretching above shoulder height at 10 weeks

  • Strengthening at 12 weeks

     

    Soft tissue stabilisation

    Arthroscopic stabilisation has largely superseded open procedures, but the outcomes are still comparable, particularly in experienced hands. Indications are similar to those

     

    described earlier. Similar to arthroscopic procedures, the shoulder may be stabilised from the front or back depending on the location of the pathology.

    Anterior stabilisation

    Risks

    These are similar to that presented earlier, and include

  • Stiffness, particularly loss of external rotation

  • Recurrence

  • Subscapularis detachment

  • Neurovascular injury

Procedure

Anaesthesia is usually general, regional or combined. Where general anaesthesia is used alone, local anaesthetic is recommended postoperatively to aid pain relief. The patient is placed in the beach chair position. A small sandbag is put under the medial scapula of the operated shoulder (this helps to externally rotate the shoulder and ‘open’ the anterior shoulder joint). An arm board can be attached to the side of the table to rest the arm. The surgical field is prepared and adequately draped and an examination under anaesthesia is performed.

The skin incision runs in the deltopectoral groove, from the coracoid to the axillary fold (with the arm adducted and internally rotated). The subcutaneous tissue is reflected with sharp and electrocautery dissection, exposing the deltopectoral interval which is marked by a fatty streak and the cephalic vein. The fascia overlying the interval is divided and the cephalic vein lateralised with the deltoid muscle. The deltoid and pectoralis major are then defined with sharp and electrocautery dissection.

 

 

Structure at risk

  • Musculocutaneous nerve – in danger from excessive traction

 

 

A retractor can be placed over the coracoid process to enhance the exposure and the clavipectoral fascia is then split vertically starting just lateral to the coracoid. This exposes the conjoint tendon. If required, the lateral third of the conjoint tendon can be divided to allow better exposure (by not detaching the coracoid or the tendon fully, the musculocutaneous nerve is protected from excessive traction). A self-retainer is placed between the coracoid/conjoint tendon medially and the deltoid muscle laterally. The arm is externally rotated to expose the subscapularis muscle. The upper two-thirds of the subscapularis can then be tenotomized approximately 1 cm from its insertion in the lesser tuberosity and dissected free of the underlying capsule. This plane is more easily found inferiorly and becomes easier as the dissection progresses medially. Alternatively, the subscapularis can be split horizontally and retracted, exposing the underlying capsule.

The capsulorrhaphy must now be undertaken. This can be performed either laterally or medially. It is the authors’ preference to perform this medially as we feel it gives a more

 

accurate anatomical reconstruction and a more reproducible elimination of the axillary pouch. To achieve a large inferior capsular shift the capsule must be dissected off all of its muscular attachments inferiorly and, indeed, postero-inferiorly in cases of marked laxity. This is best achieved with McIndoe scissors. A bone lever can then be placed inferior to the humeral neck thus protecting the axillary nerve. Depending on the degree of laxity the capsulorrhaphy can involve either a vertical capsular incision or, in cases of greater laxity, a medially based ‘T’.

The capsule is split vertically 7–10 mm from the glenoid rim, with a further horizontal incision made midway along the capsule as necessary (Figure 6.10). Two stay sutures are placed to mark the superior and inferior apices of the flaps. A Fakuda retractor is used to displace the humeral head posteriorly such that the anterior labrum is exposed. The presence of a Bankart lesion, and the degree of capsule-labral disruption, can now be visualised.

 

 

Subscapularis split

 

 

 

Figure 6.10 The medial ‘T’-shaped capsular incision.

 

The anterior glenoid neck is decorticated using a narrow osteotome or burr, and anchors are used to reattach the anterior labrum to the decorticated area of the glenoid neck. The capsular flaps are overlapped so that the inferior flap is taken superiorly and medially such that it is sutured to the medial capsule. A double-breasted suture technique using 1 Vicryl should be used. The superior flap is then sutured inferiorly taking care not to medialize the flap otherwise external rotation will be restricted. The rotator interval is then closed (Figure 6.11).

During the repair, the arm should be held in 30° of external rotation and abduction so that the repair is not over-tightened thus causing postoperative stiffness. Adequate stability and a good passive range of motion should be confirmed before the wounds are closed.

If a large, engaging Hill-Sachs lesion is present a bone block procedure (Bristow-Latarjet or iliac crest bone graft) will be required to increase the depth of the glenoid to prevent recurrent dislocation. A soft tissue procedure alone will not be adequate to restore stability.

If previously tenotomised, the subscapularis should be repaired with number 2 Ethibond. Thereafter, a layered closure using 2/0 Vicryl for the subcutaneous tissues and 3/0 Monocryl to skin is used.

 

 

 

Inferior capsular shift

 

 

 

Figure 6.11 Medially based inferior capsular shift.

 

Posterior stabilisation

Cases of posterior instability will warrant a posterior reconstructive procedure.

 

Risks

These are much the same as earlier. The posterior circumflex humeral artery and axillary nerve run together in the quadrilateral space, below teres minor. It is therefore safe provided that the correct plane of dissection is used.

Procedure

Anaesthesia is usually general, regional or combined. The patient is positioned in the prone position. A 15 cm posterior vertical incision, which extends over the spine of the scapula in the plane of the ACJ gives good access to posterior structures of the shoulder.

Posteriorly, the deltoid has a tendinous insertion onto the posterior spine of the scapula. This can be incised and reflected inferiorly giving good access to the underlying infraspinatus and teres minor tendons. More laterally an osteoperiosteal flap should be raised off the posterior lateral corner of the acromion with, if necessary, a further extension down the posterior deltoid raphe. The interval between the infraspinatus and teres minor can be developed by blunt dissection exposing the posterior capsule.

The procedure for the repair of a posterior labral injury and/or capsular laxity is similar to that described for an anteriorly based injury. A medial or laterally based capsulorrhaphy can be performed although we favour the former for the reasons described earlier.

The infraspinatus and teres minor do not need formal closure; however, meticulous repair of the deltoid should be undertaken. Thereafter, 2/0 Vicryl to superficial tissues and 3/0 Monocryl to skin are advocated.

A poly sling with body belt is used for the first 4 weeks. At 4 weeks, the body belt is removed and pendular exercises started. At 6 weeks passive stretching exercises are undertaken aiming for full elevation but only half the external rotation of the contralateral

 

side by 3 months. Strengthening exercises are begun at 6 weeks. Contact sports must be avoided for 6–9 months.

 

Bony stabilisations

In cases of significant bone loss, the threshold of which is around 13% of the glenoid, bony stabilisation procedures are preferred. They fall into two main groups: bone block (Eden-Hybinette – can be anterior or posterior) and anterior coracoid transfers (Latarjet and Bristow). Bone blocks aim to provide stability by increasing the rim of the glenoid, whereas coracoid transfers work in three main ways:

  1. Providing a dynamic sling by strengthening the inferior subscapularis muscle through transfer of the conjoint tendon

  2. Repair of the capsule and augmentation of the coracoacromial ligament

  3. Reconstruction of the glenoid face through transferring the coracoid

 

While all of these can be done arthroscopically, the benefit over an open procedure is currently questionable. We describe the open Latarjet, which is the most commonly performed.

 

Risks

General risks described earlier to open soft tissue stabilisations apply here too. There is however also a risk of non-union of the coracoid, early osteoarthritis (particularly if the graft is too lateral) and recurrent instability (particularly if the graft is too medial). The musculocutaneous nerve is particularly at risk as it runs inferomedial to the coracoid, and the axillary nerve is similarly at risk coursing medial to and inferior to the subscapularis.

 

Procedure

The patient is set up supine with a sandbag between the shoulder blades to bring the glenoid neck into view. A deltopectoral approach is utilised, as already described. The coracoid is identified and the pectoralis minor attaching medially is released, as is the coraco-acromio ligament laterally. An osteotomy is then performed to release the coracoid, using an oscillating saw and osteotomes. The conjoint tendon is gently freed from the underlying structures, taking care to protect the musculocutaneous nerve. The coracoid is then turned so that the inferior portion will eventually point to the glenoid. The coracoid is prepared with pre-drilled holes to use later and tucked into the wound.

Attention is turned to the glenoid. Abducting and externally rotating the arm brings the subscapularis muscle into better view. It is split along the border of its superior two-thirds and inferior third. This is extended towards the tendon and held apart using a Gelpi retractor.

An L- or T-shaped capsulotomy is then performed exposing the anterior glenoid. A burr is used to prepare it for the coracoid transfer; bone is removed to a bleeding edge. Ensuring an optimal position of the coracoid is fundamental to the working of the Latarjet: it must be flush with the face of the glenoid. A Fakuda retractor can be used to aid this process.

 

Once the position of the coracoid is confirmed, two screws should be passed through the coracoid and into the glenoid. These should be tightened sequentially.

The capsule is repaired and the wound closed in a similar manner to the previous descriptions. Bone wax over the coracoid stump may help control bleeding.

Postoperatively the patient should be placed in a sling for 3 weeks, after which stretches and strengthening exercises may begin. After 6 weeks, the patient may progress their range of movement and resistance exercises.

 

Shoulder arthroplasty‌

Shoulder arthroplasty can be used to effectively treat advanced degenerative joint disease and unreconstructable trauma cases. The three main types of arthroplasty are humeral hemiarthroplasties, anatomic total shoulder replacements and reverse polarity shoulder replacements. The indication, age of the patient and integrity of the rotator cuff are all important in deciding between the types. Hemiarthroplasties are essentially a humeral replacement of the total anatomical replacement leaving the glenoid intact, and thus are not considered further. Reverse polarity shoulder replacements are indicated in cuff-deficient shoulders. They replace the humeral head with a socket and the glenoid with a glenosphere, with an aim of shifting the centre of rotation of shoulder medially and inferiorly, thus improving the lever arm of the deltoid.

The approach and preparation of the humerus and glenoid are similar for all arthroplasties, so they are considered together and the nuances explained.

 

Common indications

  • Osteoarthritis

  • Inflammatory arthritis

  • Avascular necrosis

  • Trauma – proximal humeral fractures

  • Postinfective arthritis

  • Instability arthropathy

  • Cuff tear arthropathy

  • Arthritis secondary to glenoid dysplasia or epiphyseal dysplasia

    Contraindications

  • Active infection

    Risks

    Patients should be counselled as to the short-, medium- and long-term risks. These should include

  • Infection

  • Neurovascular injury

  • Stiffness

  • Aseptic loosening

     

  • Fracture

  • Revision

  • Acromial fracture

    Procedure

    Anaesthesia can be general, regional or combined. Where general anaesthesia is used alone, additional local anaesthetic infiltration or patient-controlled anaesthesia is recommended for pain relief. Antibiotics are given at induction. The patient is placed in the reclining beach chair position and pulled to the side to allow extension and rotation of the arm. A small sandbag is put under the shoulder. The surgical field is prepared and draped.

    Landmarks include

     

  • Acromioclavicular joint

  • Anterolateral/posterolateral corners of acromion

  • Coracoid

 

Two approaches are possible for shoulder arthroplasty. These are the deltopectoral and the anterosuperior approaches.

Deltopectoral

An incision is made from coracoid toward the axillary fold, extending laterally to the anterior arm. The subcutaneous tissue is reflected with sharp and electrocautery dissection exposing the deltopectoral interval, which is marked by a fatty streak and the cephalic vein. The fascia overlying the interval is divided and the cephalic vein lateralised with the deltoid muscle. In a tight shoulder the pectoralis major tendon can be released at its superior border taking care not to injure the underlying biceps tendon.

 

Structures at risk

The cephalic vein is at risk when entering the deltopectoral interval. The axillary and musculocutaneous nerves are in danger from excessive traction.

 

 

To enhance the exposure a retractor can be placed over the coracoid process and then the clavipectoral fascia is split vertically starting just lateral to the coracoid, extending the incision just lateral to the conjoint tendon and its muscle belly.

To improve external rotation the coracohumeral ligament should also be released at its coracoid origin. The deltoid is then mobilised from the tissues of the subacromial space and retracted posterolaterally. Provided that the retractors are placed above the inferior subdeltoid, bursal reflection of the axillary nerve should be safe. If better access is required, as may be the case with a medialized glenoid, the lateral third of the conjoint tendon can be divided to allow better exposure or alternatively a coracoid tip osteotomy can be performed. However, care should be taken not to retract the conjoint tendon excessively as

 

this could put the musculocutaneous nerve at risk. The arm is externally rotated to expose the subscapularis muscle.

The anterior circumflex humeral vessels, which are found at the inferior border of the subscapularis tendon, are then ligated if necessary. The axillary nerve can be exposed so that its position is known and avoided during the remainder of the procedure.

The degree of external rotation that can be achieved should now be assessed. If this is deficient then a subscapularis lengthening procedure may be required. This may involve a layered subscapularis tenotomy or ‘Z plasty’, and this will need to be planned at this stage. If external rotation is adequate the subscapularis tendon is then tenotomised 1 cm medial to its humeral insertion and raised on stay sutures. This can be taken as one layer with the underlying capsule. In order to lengthen the subscapularis the rotator interval will need to be incised and then the capsule will need to be released from the glenoid neck. Protecting the subscapularis is fundamental to the functioning of both anatomical and reverse prostheses, as the subscapularis-infraspinatus force couple centre the components.

As the capsule is incised an inferior capsular release can be performed, and provided that the axillary nerve has already been identified the nerve should not be at risk. A blunt retractor can be placed inferiorly to protect the nerve and then the humeral head is dislocated anteriorly by applying gentle external rotation to the arm. The LHB tendon should be inspected and tenotomised or tenodesed as necessary. It is often torn in cases of advanced arthritis.

The head is then prepared by removing any osteophytes so that the true anatomical neck of the humerus can be identified. Further preparation will vary depending on the implant; however, the principles are that

  1. As much of the tuberosities as possible are retained, important for rotational control of the implant.

  2. Enough bone must be resected to allow a suitable implant to function optimally.

  3. The arm length should be restored.

 

For the purpose of this description, a standard stemmed implant will be used. An oscillating saw is used to resect the humeral head at its anatomical neck. If this has been adequately demarcated during preparation, it can be done freehand, otherwise jigs should be used such that the height and version of the resection are appropriate. The resected humeral head is then used as a guide for the size of the subsequent humeral head replacement in the case of an anatomical replacement. With the head resected the remainder of the circumferential glenoid release can be performed and the glenoid inspected. Some implant systems advocate preparation of the humerus at this point, but not definitive implantation, rather a cap can be placed over a prepared humerus to offer protection while glenoid preparation takes place.

Once the capsule is released there should be adequate space to approach the glenoid perpendicular to its face such that preparation can be achieved with the appropriate implant jigs. The labrum and surrounding osteophytes should be excised to aid exposure. Excising the inferior lip of the glenoid may aid implant positioning. The process of this

 

preparation will vary according to the implant. To assess the true version of the glenoid it is useful to place a narrow retractor down the anterior glenoid neck so that the axis of the glenoid is known prior to definitive glenoid preparation. Preoperative planning and templating will aid this step.

If not already done so, the humerus can now be prepared using sequentially sized rasps and when the appropriate size is established a trial prosthesis can be constructed and inserted into the humerus. After reducing the implant the surgeon should check the offset, version and soft tissue tension of the trial prosthesis and if satisfactory the definitive prosthesis can be implanted.

 

Anterosuperior

An 8 cm incision is started just posterior to the front of the ACJ, directed towards the anterolateral corner of the acromion and down the anterolateral deltoid.

 

Structure at risk

Axillary nerve – 5 cm below the lateral acromion (below the inferior reflection of the subdeltoid bursa).

 

 

The deltoid is bluntly split at the anterior raphe (the junction of anterior and middle third of the deltoid). The deltoid is detached off the anterior acromion with an osteoperiosteal sleeve. This is extended medially to the ACJ. The subdeltoid bursa is split longitudinally palpating the inferior bursal reflection which denotes the position of the axillary nerve.

The coracoacromial ligament is detached from the undersurface of the acromion. Anterior acromioplasty and ACJ excision can be carried out if required.

Blunt soft tissue release is carried out around the cuff. The coracohumeral ligament is released at its coracoid origin. This improves the external rotation. With the arm in external rotation, a bone retractor is inserted on the medial side of the humeral neck, marking the inferior border of the subscapularis muscle. This is detached laterally from its insertion to the lesser tuberosity together with the capsule. Stay sutures are inserted.

If a biceps tenodesis is required, a stay suture is placed and the tendon cut. The humeral head is dislocated anteriorly with external rotation and extension. A Bankart skid is placed between the glenoid and the head. Osteophytes are excised. A bone spike is inserted on the medial side of the humeral neck, under the subscapularis to protect the axillary nerve. Humeral and glenoid preparation is then performed as previously described.

 

Closure

During closure, the subscapularis tendon is repaired using number 2 Ethibond with the arm held in a position of 30° external rotation. This prevents over-tightening of the tendon repair. A deltoid repair is then performed to the anterior acromion if the anterosuperior

 

approach was used. A 2/0 Vicryl to the subcutaneous tissues and 3/0 Monocryl to skin completes the closure.

 

Postoperative

A poly sling is used for 6 weeks. Recommended are passive and active assisted exercises to 90° of forward elevation and external rotation to 0° for 6 weeks. Full passive movement to re-establish full range is recommended thereafter followed by active ranging and strengthening exercises as able.

 

Viva questions‌

  1. What are the treatment options for an irrepairable rotator cuff tear in a 70 year old patient with minimal arthritis?

  2. How does a reverse polarity shoulder replacement work?

  3. How would you counsel a 16 year old aspiring professional rugby player following a first time traumatic anterior shoulder dislocation?