Shoulder & Elbow Module July 22 Flashcards
A 12-year-old boy who pitches on two “select” baseball teams has had pain in his dominant right shoulder for the past 6 weeks. The pain is present only with throwing and is associated with decreased throwing velocity and control. He has no radiation of pain or paraesthesias of the upper extremity. An AP radiograph and MRI scan are shown in Figures 19a and 19b, respectively - widening proximal humerus physis
Management should consist of:
rest from throwing activities. a subacromial corticosteroid injection. open reduction and internal fixation. arthroscopic labral repair. biopsy of the proximal humerus.
Rest from throwing activities.
The imaging study demonstrates characteristics of Little Leaguer’s shoulder, including physeal widening. This condition is secondary to overuse (typically throwing) and responds well to rest from the inciting activity. There is no evidence from the patient’s history or examination that he has an impingement syndrome, nor is there any indication of labral pathology on the MRI scan. The changes in the proximal humerus are classic for this condition and are not suggestive of a neoplastic process requiring biopsy for definitive diagnosis.
Little Leaguer’s shoulder is an overuse injury occuring in young baseball pitchers resulting in epiphysiolysis of the proximal humerus (a Salter Harris Type 1 injury).
Diagnosis is made with radiographs of the shoulder showing a widened proximal humerus physis in comparison to contralateral shoulder.
Treatment is cessation of throwing, followed by PT and progressive throwing program after sufficient rest.
M>F
11-16 years - skeletally immature overhead athletes
10% all shoulder pain in paediatrics is related to throwing.
Mechanism: repetitive torsional and distractive stresses at the physis (SHI injury) - affects hypertrophic zone of physis (weakest portion of the growth plate)
Pitching occurs in 3 phases:
- Late cocking: shoulder is maximally externally rotated, leading to extreme rotatory torque through the growth plate, approximately 400% greater than the fragile physeal cartilage can tolerate
- Deceleration: opposing forces of forward arm motion and rotator cuff results in excessive eccentric physeal stress
Breaking pitches are implicated
Number of pitches is the most important factor
Presents with decreased pitch velocity and accuracy - causes diffuse arm and shoulder pain with throwing - worse in late cocking or deceleration phases.
Pain resolves with rest.
Examination: Point tenderness over lateral proximal humerus, at the level of the physis.
Pain reproduced with shoulder rotation, Glenohumeral internal rotation deficit.
During which phase of the overhead throwing cycle is a baseball pitcher most likely to rupture the medial ulnar collateral ligament complex of the elbow?
Follow-through Ball release Early acceleration Early cocking Wind-up
Early Acceleration
The medial UCL is subjected to near-failure tensile stresses during the late cocking/early acceleration phase of throwing.
The medial ulnar collateral ligament, or medial collateral ligament of the elbow, is composed of three bundles:
- an anterior bundle
- a posterior bundle
- a variable transverse oblique bundle.
The anterior bundle of the ulnar collateral ligament is the primary restraint to valgus force of the elbow from 30 to 120 degrees of flexion.
Biomechanical testing has shown that valgus forces as high as 64 N.m at the elbow during late cocking and early acceleration phases of throwing with compressive forces of 500 N at the lateral radiocapitellar articulation as the elbow moves from 110 to 20 degrees of flexion and velocities as high as 3000 deg/sec.
Mechanisms of injury MUCL:
- Acute trauma: often associated with elbow dislocations
- Overuse injuries:
+ Microtrauma from repetitive valgus stress leads to rupture of anterior band of MUCL
+ Baseball pitchers place significant valgus stress on the elbow in the late cocking and early acceleration phase of throwing
+ elbow valgus load increases with poor throwing mechanics and decreases with trunk-scapular kinesis, forearm pronation, dynamic flexor-pronator stabilization
- Iatrogenic : excessive olecranon osteophyte resection places MCL at risk
For Grade III AC joint separations, surgical treatment results in which of the following when compared to non-operative management?
Faster return to play
Increased range of motion
Increased functional rotator cuff strength
Decreased funtional rotator cuff strength
Higher complication rate
Higher complication rate
Treatment of grade III AC separations remains somewhat controversial. A recent systematic review by Spencer concluded that the results of surgical treatment were not clearly any better than non-operative, had a higher complication rate, and a longer recovery prior to return to sport/work.
An acromioclavicular joint injury, otherwise known as a shoulder separation, is a traumatic injury to the acromioclavicular (AC) joint with disruption of the acromioclavicular ligaments and/or coracoclavicular (CC) ligaments.
Diagnosis is made with bilateral focused shoulder radiographs to assess for AC and CC interval widening.
Treatment is immobilzation or surgical reconstruction depending on patient activity levels, degree of separation and degree of ligament injury.
More common in male athletes - common injury making up 9% of shoulder girdle injuries.
Often sustained by falling onto the shoulder or a direct blow to the shoulder.
ACJ: diarthrodial joints composed of the articulation between the scapula (medial acromion) and the lateral clavicle with fibrocartilaginous intra-articular disc (involutes with age and tends to disintegrate by the age of 40).
Joint surface has an oblique orientation.
Motion: Primary gliding motion with minimal rotational motion (only 8deg rotation through ACJ due to synchronous scapuloclavicular motion).
Stability:
- Static:
+ Joint capsule
+ AC ligaments: controls horizontal motion and AP stability - S,I,A & P elements - with posterior and superior most important for stability.
+ Coracoclavicular ligaments: controls vertical motion and superior-inferior stability -
CONOID (medial - inserts on clavicle 4.5cm medial to the lateral edge, most important for vertical stability).
TRAPEZOID (lateral, inserts on clavicle 3cm medial to lateral edge)
- Dynamic:
Anterior deltoid and trapezius
Ex: Lateral clavicle/ACJ tenderness, abnormal contour of the shoulder compared to contralateral side.
ACJ exacerbation tests:
- O’Brien’s Test: superficial pain localised to ACJ is suggestive of ACJ pathology, whereas deep pain is more suggestive of a SLAP lesion.
- Crossbody adduction
Stability assessment:
- Horizontal (anterior-posterior) stability evaluates AC ligaments: cross-body adduction, horizontal instability (ISAKOS type 3B) may indicate need for more aggressive treatment
- Vertical (superior-inferior) stability evaluates CC ligaments
Rookwood Classification:
Type I: AC ligament sprain, no instability, reducible. Tx: sling
Type II: AC ligament torn, CC ligament sprain, AC horizontal instability. Reducible.
XR: ACJ disruption - Increased CC distance <25% vs contralateral.
Tx: sling.
Type III: Torn AC & CC ligaments. Reducible. Vertical Instability.
IIIA: No horizontal instability.
IIIB: horizontal instability.
XR: ACJ disruption - Increased CC distance <25%
Tx: Controversial.
Type IV: Torn AC & CC ligaments. Skin tenting and posterior fullness. Not reducible.
XR: Lateral clavicle displaced posterior through trapezius on the axillary lateral XR.
Tx: Surgical
Type V: Torn AC & CC ligaments. Not reducible. Severe shoulder droop, does not improve with shrug.
XR: ACJ disruption - Increased CC distance >100%
Tx: Surgical
Type VI: Torn AC & CC ligaments. Not reducible. Rare - associated injuries and paraesthesias more common.
XR: Inferior dislocation of lateral clavicle, lying either in subacromial or subcoracoid position
Tx: Surgical
Surgical techniques:
- Ligament reconstruction with soft tissue graft:
+ Modified Weaver-Dunn: distal clavicle excision with transfer of coracoacromial ligament to the distal clavicle to recreate CC ligament
+ autograft
+ allograft
- Fixation: suture, hook plate, CC screw (Bosworth), cortical flip button (e.g Dog Bone)(+/- arthroscopic assistance), K-wire
Rehabilitation
Sling immobilization for 6 weeks, no shoulder range of motion
Return to full activity after 6 months
ORIF with CC screw fixation (Bosworth): fallen out of favour - screw placement from distal clavicle to coracoid, superior to inferior.
Pros: Rigid internal fixation
Cons: Danger of being too long and damaging critical structures below coracoid. Requires routine screw removal 8-12 weeks post op to prevent screw breakage (due to normal movement between clavicle and scapula.
Complicated often by hardware irritation and failure at level of screw purchase in the coracoid.
ORIF with CC suture fixation:
- Approach is proximal aspect of the anterolateral approach to the shoulder. Suture is placed either around or through the clavicle and around the base of the coracoid (can also use suture anchors for coracoid fixation).
Pros: No risk of hardware failure or migration.
Cons: Suture not as strong as screw fixation and requires careful suture passage inferior to coracoid due to proximity of crucial NV structures.
Complications: suture erosion causing distal third clavicle fracture, hardware irritation.
ORIF with AC hook plate:
- Expose distal and middle clavicle and use a standard hook plate over the superior distal clavicle.
Pros: rigid fixation.
Cons: hardware irritation - removal required if symptomatic.
Complications: acromial erosion, hook pullout
Phemister Technique (ORIF with AC pin fixation)
- Can be percutaneous - smooth wire or pin fixation directly across ACJ.
Cons: hardware irritation
Complications: high incidence of pin migration - limits use.
CC ligament reconstruction with coracoacromial (CA) ligament (Modified Weaver-Dunn)
- Open or arthroscopic distal clavicle excision and transfer of coracoacromial ligament to the distal clavicle to recreate CC ligament, then reinforce with internal fixation
Cons: coracoacromial ligament only 20% as strong as normal CC ligament, lack of internal fixation risks failure of soft tissue repair
CC ligament reconstruction with free tendon graft
approach
-Open or arthroscopically-assisted
grafts:
Autograft: palmaris longus, semitendinosus
Allograft: tibialis anterior
Figure-of-eight passage of graft, looping around coracoid and fixation through clavicular tunnels then reinforce with internal fixation.
Pros: graft reconstruction more closely recreates strength of native CC ligament
Cons: standard risks of allograft use or autograft harvest
lack of internal fixation risks failure of soft tissue repair
Posterior shoulder tightness can lead to a glenohumeral internal rotation deficit (GIRD). This has been linked most closely to which of the following shoulder pathologies?
Internal impingement Humeral avulsion of the glenohumeral ligament Subacromial impingement Bicep tendinitis Hill-Sachs lesion
Internal impingement
Repetitive overhead throwing can lead to posterior capsular stiffness and relative loss of internal rotation (GIRD). This may shift the contact point posterior and superior on the glenoid, leading to internal impingement where the greater tuberosity impinges on the posterosuperior labrum and posterior rotator cuff when the arm is abducted and externally rotated. Initial treatment involves posterior capsular stretching.
Myers et al evaluated two groups of throwing athletes, one with a diagnosis of internal impingement and one without, to compare the degree of GIRD/posterior capsular tightness and its correlation with increased external rotation gain. They found that throwing athletes with internal impingement demonstrated significantly greater GIRD and posterior shoulder tightness, and that management should include stretching to restore flexibility to the posterior shoulder.
Tyler et al sought to determine if improvements in GIRD and/or decreased posterior shoulder tightness were associated with a resolution of symptoms in 22 patients with internal impingement. After an average of 7 weeks of physical therapy, they found that resolution of symptoms was related to correction of posterior shoulder tightness but not correction of GIRD.
Glenohumeral internal rotation deficit (GIRD) is a condition resulting in the loss of internal rotation of the glenohumeral joint as compared to the contralateral shoulder, most commonly seen in the throwing athlete.
Diagnosis is made clinically with a decrease in internal rotation, increase in external rotation, with a decrease in total arc of rotation compared to the contralateral shoulder.
Treatment consists of physical therapy with a focus on posteroinferior capsular stretching.
Pathoanatomy: tightening of the posterior capsule or posteroinferior capsule leads to translation of humeral head (capsular restraint mechanism). Translation of humeral head is in the OPPOSITE direction from the area of capsular tightening. Posterior capsular leads to anterosuperior translation of the humeral head in flexion.
Posteroinferior capsular tightness leads to posterosuperior translation of the humeral head in ABER.
The anterior capsule is stretched.
Associated conditions:
- Glenohumeral instability
- Internal impingement: abutment of the greater tuberosity against the posterosuperior glenoid during abduction and external rotation leads to pinching of posterosuperior rotator cuff
- Articular-sided partial rotator cuff tears - due to tensile failure in excessive rotation and internal impingement
- SLAP lesion: throwers with GIRD are 25% more likely to have a SLAP lesion. Peel-back mechanism (biceps anchor and postero superior labrum peels back) during late cocking because of posterosuperior translation of humeral head and change in biceps vector force posteriorly
On examination:
- Increased sulcus sign - due to stretching of anterior structures that resist external rotation (coracohumeral ligament, rotator interval).
- Characterised by altered glenohumeral ROM: decrease in IR and increase in ER.
When loss of IR is less than gain in ER, the shoulder retains normal kinematics, but when loss of IR exceeds gain in ER it leads to deranged kinematics.
Tx: Rest and physio - sleeper stretches to stretch posteroinferior capsule
Operative if extensive PT fails: posteroinferior capsule release or anterior stabilisation. Should immediately gain 65 deg internal rotation post op.
A 60-year-old patient fell down a flight of stairs and injured their right arm. Since the fall they are unable to move their extremity due to pain. Prior to the fall, the patient denied any pain in the shoulder or upper arm. Currently, the patient is neurovascularly intact. Figures A and B are the radiographs at the time of presentation. What is the best treatment option for this patient?
XR demonstrate well seated TSA with periprosthetic fracture at the level of the tip of the prosthesis.
Revision rTSA with cemented long-stem prosthesis
Revision rTSA with cementless long-stem prosthesis
ORIF with hybrid locking plate and cerclage cables
ORIF with lag screw fixation and neutralization plating
Nonoperative treatment
ORIF with hybrid locking plate and cerclage cables
The patient has sustained a Wright and Cofield type B periprosthetic humeral shaft fracture with a stable prosthesis. The best treatment option for this would involve ORIF with hybrid locking plate and cable construct.
Periprosthetic humeral shaft fractures are a relatively rare complication occurring in approximately 0.6-3% of patients that have undergone shoulder replacement procedures. These fractures pose treatment challenges as the prosthesis disrupts endosteal blood supply, causing higher nonunion rates.
Wright and Cofield system:
Type A fractures are proximal to the stem tip and are treated with ORIF;
Type B fractures are at the level of the stem tip and are treated with ORIF;
Type C fractures are distal to the stem tip and can be initially treated nonoperatively.
Steinmann et al. reviewed the treatment of periprosthetic humeral shaft fractures.
For intraoperative fractures, the authors recommended placement of a long stem prosthesis that bypasses the fracture site by at least 2 cortical diameters.
For postoperative type A and B fractures, treatment depends on whether the stem is loose or well fixed. Loose prostheses necessitate revision long stem component with supplementary fixation, whereas well-fixed stems require hybrid plate fixation. Type C fractures can be treated non-operatively, but in the presence of nonunion may require plate fixation with or without allograft struts.
High incidence of radial nerve palsy with distal humerus fractures - most often neuropraxia not requiring operative management.
Figures A and B are AP and lateral radiographs demonstrating a Wright and Cofield type B periprosthetic humeral shaft fracture. Illustration A depicts the Wright and Cofield classification system.
Incorrect Answers:
Answer 1: In the setting of a loose prosthesis, revision arthroplasty with a long stem implant would be the ideal choice. Cement fixation can be utilized in the presence of osteoporotic bone, but care must be taken to prevent cement extrusion into the fracture site. In this case, the stem is well fixed and revision arthroplasty is unnecessary.
Answer 2: Revision arthroplasty is indicated in a loose stem, but in this case, the stem is well fixed.
Answer 4: Lag screw fixation is not recommended with these fractures. Current data suggest good outcomes with hybrid locking plates and cerclage cables.
Answer 5: Type C fractures may be amenable to nonoperative treatment. However, when there is involvement near the stem tip there is a high risk of nonunion without adequate fixation due to poor endosteal blood flow in this region.
A 35-year-old carpenter has pain in the antecubital fossa that is worse with turning a screwdriver. He has undergone non-operative treatment for 6 months without relief. On physical examination his hook test is normal and there is pain and weakness with resisted supination. Radiographs are shown in Figures A-C. A MRI of the right elbow is shown in Figure D. The next most appropriate treatment is?
Figures A-C are normal radiographs of the elbow. Figure D is a cross-referenced axial and coronal T2 MRI that demonstrates increased signal around distal biceps insertion.
Exploration of the radial tunnel Superficial radial neurectomy Detachment and repair of the biceps tendon Transfer of the biceps to the brachialis EMG with nerve conduction study
Detachment and repair of the biceps tendon
While complete traumatic rupture of the distal biceps is more common, partial tears have been reported in the literature. The most common presentation is pain in the antecubital fossa worse with resisted supination.
Conservative management consists of NSAID’s, splinting and physical therapy. The distal biceps hook test is helpful in detecting full thickness distal biceps tears but not partial tears.
In one study by Vardakas et al, 7 partial distal biceps ruptures were treated with surgical debridement and reattachment with all patients reporting a significant decrease in their pain. Transfer to the brachialis improves flexion strength but not supination.
Ramsey et al present a review article on distal biceps tendon injuries. They state that the most successful management of partial distal biceps tears that have failed conservative management is to surgically treat it like a complete rupture with release and surgical reattachment of the distal biceps to the radial tuberosity.
Distal Biceps Avulsions are injuries to the biceps tendon at the radial tuberosity insertion that generally occurs due to a sudden excessive eccentric contraction of the biceps brachii.
Diagnosis can be made clinically in the setting of complete tears with a hook test. MRI studies can be used to discern between a complete tear and a partial tear.
Treatment can be nonoperative or operative depending on patient age, patient activity demands, chronicity of tear, and degree of tear.
Contents of antecubital fossa (medial to lateral):
- Median nerve -> brachial artery -> biceps tendon -> radial nerve
- Radial recurrent vessels lie superficial to biceps tendon
Distal biceps tendon possesses two distinct insertions:
- Short head attaches distally on radial tuberosity (thin sliver), origin is coracoid processs, is a better flexor
- Long head attaches proximally on radial tuberosity (oval footprint), origin is the superior lip of the glenoid and glenoid labrum, is a better supinator as attachment is furthest from axis of rotation (attaches to apex of radial tuberosity). Independent function to prevent anterior, inferior and superior translation of humeral head against proximal pull of short head of biceps
Lacertus fibrosus
Distal to the elbow crease, the biceps tendon gives off, from its medial side, the lacertus fibrosus (bicipital aponeurosis or biceps fascia).
Originates from the distal short head of the biceps tendon. Lacertus passes obliquely across the cubital fossa, running distally and medially, helping to protect the underlying brachial artery and median nerve. It is continuous with the deep fascia of the flexor tendon origin, envelopes flexor muscle bellies - may be mistaken for an intact distal biceps tendon on clinical exam.
Patient often experiences a painful “pop” as the elbow is eccentrically loaded from flexion to extension.
Ex: varying degree of proximal retraction of the muscle belly (“reverse Popeye sign”), medial ecchymosis, palpable defect.
Loss of more supination than flexion strength (loss 30% flexion, 40% supination, 50% sustained supination)
Hook test - ask patient to actively flex elbow to 90 and to fully supinate forearm - examiner then attempts to hook the lateral edge of the biceps tendon with index finger - if intact/partially torn then finger can be inserted 1cm beneath the tendon.
False positive: partial tear, intact lacertus fibrosis, underlying brachialis tendon
Ruland Biceps squeeze (akin to Simmonds for Achilles) - elbow held in 60-80° of flexion with the forearm slightly pronated. One hand stabilizes the elbow while the other hand squeezes across the distal biceps muscle belly. A positive test is failure to observe supination of the patient’s forearm or wrist.
Subacute/chronic ruptures may be treated successfully with direct repair (without allograft) - may need to hyperflex elbow to achieve fixation. Hyperflexion does NOT lead to loss of elbow ROM or flexion contracture
timing.
Surgical treatment should occur within a few weeks from the date of injury - further delay may preclude a straightforward, primary repair.
A more extensile approach may be required in a chronic rupture to retrieve the retracted and scarred distal biceps tendon.
Limited antecubital fossa incision:
- Interval between the brachioradialis and pronator teres - radial (lateral) retraction of the brachioradialis and medial retraction of the pronator teres.
Lateral antebrachial cutaneous nerve (LABCN) is identified as it exits between the biceps and brachialis at antecubital fossa.
Recurrent radial vessels encountered and either coagulated or carefully dissected and retracted.
Protect PIN by limiting forceful lateral retraction and maintaining supination
Cortical button - tendon end is whip-stitched with the suture ends placed into two central holes of the button.
Acorn reamer is used to ream through the anterior cortex after exposing tuberosity.
A smaller hole is then drilled through the far cortex to allow the button to be passed across the far cortex.
Button is flipped to lie on far cortex, and suture ends are tensioned (tension slide) to bring tendon into tunnel
Complications: injury to the LABCN is most common whereas radial nerve or PIN injury is most severe - risk has decreased with new tendon fixation techniques that require less dissection in the antecubital fossa
Synostosis and resulting loss of pronation/supination: avoid exposing periosteum of ulna & avoid dissection between the radius and ulna
Heterotopic ossification
Postoperative: immobilize in 110° of flexion and moderate supination
A 46-year-old woman fell from her bicycle and sustained the injury shown in Figure 24. Which of the following ligaments has been disrupted?
XR: Increased CC distance > 100% of contralateral
Acromioclavicular Acromioclavicular and coracoclavicular Coracoclavicular Coracoacromial and sternoclavicular Sternoclavicular
Acromioclavicular and coracoclavicular
The radiograph shows a type V acromioclavicular joint injury. Type V injuries involve disruption of the acromioclavicular and coracoclavicular ligaments. Type I injuries involve a sprain of the acromioclavicular joint ligaments. Type II injuries involve disruption of the acromioclavicular joint ligaments; the coracoclavicular ligaments are partially injured. Sternoclavicular ligaments stabilize the medial clavicle and the sternum; they are not damaged with acromioclavicular joint dislocations.
An acromioclavicular joint injury, otherwise known as a shoulder separation, is a traumatic injury to the acromioclavicular (AC) joint with disruption of the acromioclavicular ligaments and/or coracoclavicular (CC) ligaments.
Diagnosis is made with bilateral focused shoulder radiographs to assess for AC and CC interval widening.
Treatment is immobilzation or surgical reconstruction depending on patient activity levels, degree of separation and degree of ligament injury.
More common in male athletes - common injury making up 9% of shoulder girdle injuries.
Often sustained by falling onto the shoulder or a direct blow to the shoulder.
ACJ: diarthrodial joints composed of the articulation between the scapula (medial acromion) and the lateral clavicle with fibrocartilaginous intra-articular disc (involutes with age and tends to disintegrate by the age of 40).
Joint surface has an oblique orientation.
Motion: Primary gliding motion with minimal rotational motion (only 8deg rotation through ACJ due to synchronous scapuloclavicular motion).
Stability:
- Static:
+ Joint capsule
+ AC ligaments: controls horizontal motion and AP stability - S,I,A & P elements - with posterior and superior most important for stability.
+ Coracoclavicular ligaments: controls vertical motion and superior-inferior stability -
CONOID (medial - inserts on clavicle 4.5cm medial to the lateral edge, most important for vertical stability).
TRAPEZOID (lateral, inserts on clavicle 3cm medial to lateral edge)
- Dynamic:
Anterior deltoid and trapezius
Ex: Lateral clavicle/ACJ tenderness, abnormal contour of the shoulder compared to contralateral side.
ACJ exacerbation tests:
- O’Brien’s Test: superficial pain localised to ACJ is suggestive of ACJ pathology, whereas deep pain is more suggestive of a SLAP lesion.
- Crossbody adduction
Stability assessment:
- Horizontal (anterior-posterior) stability evaluates AC ligaments: cross-body adduction, horizontal instability (ISAKOS type 3B) may indicate need for more aggressive treatment
- Vertical (superior-inferior) stability evaluates CC ligaments
Rookwood Classification:
Type I: AC ligament sprain, no instability, reducible. Tx: sling
Type II: AC ligament torn, CC ligament sprain, AC horizontal instability. Reducible.
XR: ACJ disruption - Increased CC distance <25% vs contralateral.
Tx: sling.
Type III: Torn AC & CC ligaments. Reducible. Vertical Instability.
IIIA: No horizontal instability.
IIIB: horizontal instability.
XR: ACJ disruption - Increased CC distance <25%
Tx: Controversial.
Type IV: Torn AC & CC ligaments. Skin tenting and posterior fullness. Not reducible.
XR: Lateral clavicle displaced posterior through trapezius on the axillary lateral XR.
Tx: Surgical
Type V: Torn AC & CC ligaments. Not reducible. Severe shoulder droop, does not improve with shrug.
XR: ACJ disruption - Increased CC distance >100%
Tx: Surgical
Type VI: Torn AC & CC ligaments. Not reducible. Rare - associated injuries and paraesthesias more common.
XR: Inferior dislocation of lateral clavicle, lying either in subacromial or subcoracoid position
Tx: Surgical
Surgical techniques:
- Ligament reconstruction with soft tissue graft:
+ Modified Weaver-Dunn: distal clavicle excision with transfer of coracoacromial ligament to the distal clavicle to recreate CC ligament
+ autograft
+ allograft
- Fixation: suture, hook plate, CC screw (Bosworth), cortical flip button (e.g Dog Bone)(+/- arthroscopic assistance), K-wire
Rehabilitation
Sling immobilization for 6 weeks, no shoulder range of motion
Return to full activity after 6 months
ORIF with CC screw fixation (Bosworth): fallen out of favour - screw placement from distal clavicle to coracoid, superior to inferior.
Pros: Rigid internal fixation
Cons: Danger of being too long and damaging critical structures below coracoid. Requires routine screw removal 8-12 weeks post op to prevent screw breakage (due to normal movement between clavicle and scapula.
Complicated often by hardware irritation and failure at level of screw purchase in the coracoid.
ORIF with CC suture fixation:
- Approach is proximal aspect of the anterolateral approach to the shoulder. Suture is placed either around or through the clavicle and around the base of the coracoid (can also use suture anchors for coracoid fixation).
Pros: No risk of hardware failure or migration.
Cons: Suture not as strong as screw fixation and requires careful suture passage inferior to coracoid due to proximity of crucial NV structures.
Complications: suture erosion causing distal third clavicle fracture, hardware irritation.
ORIF with AC hook plate:
- Expose distal and middle clavicle and use a standard hook plate over the superior distal clavicle.
Pros: rigid fixation.
Cons: hardware irritation - removal required if symptomatic.
Complications: acromial erosion, hook pullout
Phemister Technique (ORIF with AC pin fixation)
- Can be percutaneous - smooth wire or pin fixation directly across ACJ.
Cons: hardware irritation
Complications: high incidence of pin migration - limits use.
CC ligament reconstruction with coracoacromial (CA) ligament (Modified Weaver-Dunn)
- Open or arthroscopic distal clavicle excision and transfer of coracoacromial ligament to the distal clavicle to recreate CC ligament, then reinforce with internal fixation
Cons: coracoacromial ligament only 20% as strong as normal CC ligament, lack of internal fixation risks failure of soft tissue repair
CC ligament reconstruction with free tendon graft
approach
-Open or arthroscopically-assisted
grafts:
Autograft: palmaris longus, semitendinosus
Allograft: tibialis anterior
Figure-of-eight passage of graft, looping around coracoid and fixation through clavicular tunnels then reinforce with internal fixation.
Pros: graft reconstruction more closely recreates strength of native CC ligament
Cons: standard risks of allograft use or autograft harvest
lack of internal fixation risks failure of soft tissue repair
A 22-year-old volleyball player reports the insidious onset of superior and posterior shoulder pain. Radiographs are normal. An MRI scan is shown in Figure 25. What is the most specific physical examination finding?
MRI: spinoglenoid cyst
Positive impingement sign Positive apprehension Positive active compression Weakness of external rotation Weakness of abduction
Weakness of external rotation
Overhead athletes are prone to a number of problems involving the shoulder. Pitchers and volleyball players are susceptible to posterior superior labral tears and internal impingement. These patients will have posterior superior shoulder pain, a positive relocation sign, and a positive active compression test. Occasionally, these posterior superior labral tears are associated with a spinoglenoid cyst as seen in the MRI scan. These cysts cause compression of the suprascapular nerve which manifests primarily as weakness of the infraspinatus, resulting in weakness of external rotation.
Suprascapular neuropathy is compression of the suprascapular nerve that most commonly occurs at the suprascapular notch or spinoglenoid notch by a mass (i.e cyst).
Diagnosis can be suspected clincally with weakness and atrophy of the infraspinatous or supraspinatous and confirmed with MRI studies showing cysts in the suprascapular notch or spinoglenoid notch.
Treatment of suprascapular nerve compression at the suprascapular notch requires decompression of a cyst when present. Treatment of a spinoglenoid cyst requires either decompression or repair of an associated labral lesion (if present).
Suprascapular notch entrapment:
Proximal compression of supra scapular nerve in the supra scapular notch leads to weakness of both supraspinatus and infraspinatus. Suprascapular nerve (C5,6) - emerges off superior trunk of brachial plexus, travels across posterior triangle of neck to scapula innervation of supraspinatus and infraspinatus. Compression can be due to a ganglion cyst (often associated with labral tears), transverse scapular ligament entrapment, fracture callus.
Spinoglenoid notch entrapment:
Distal compression of supra scapular nerve therefore weakness of infraspinatus only. Compression can be due to posterior labral tears -> cyst, spinoglenoid ligament, spinoglenoid notch ganglion, traction injury (volleyball players), transglenoid fixation
Suprascapular ligament arises from medial base of coracoid and overlies suprascapular notch - suprascapular artery runs above and suprascapular nerve runs below.
Spinoglenoid ligament arises near spinoglenoid notch and overlies distal suprascapular nerve
What is the average medial-to-lateral distance of the supraspinatus tendon insertion at its footprint on the greater tuberosity?
6-8mm 14-16mm 20-22mm 24-26mm 30-32mm
Cadaveric studies have shown the average medial-to-lateral distance of the supraspinatus tendon footprint on the greater tuberosity is 14-16mm.
A 28-year-old professional baseball pitcher sustains a complete rupture of his ulnar collateral ligament. He is neurovascularly intact on exam. Which of the following surgical reconstruction techniques has been shown to result in the lowest complication rate and best patient outcome?
Splitting of flexor-pronator mass, figure-of-8 graft fixation.
Splitting of flexor-pronator mass, docking graft fixation.
Splitting of flexor-pronator mass, docking graft fixation, ulnar nerve transposition.
Detachment of flexor-pronator mass, figure-of-8 graft fixation, ulnar nerve transposition.
Detachment of flexor-pronator mass, docking graft fixation, ulnar nerve transposition.
Splitting of flexor-pronator mass, docking graft fixation.
Ulnar collateral ligament (UCL) reconstruction using a flexor-pronator muscle-splitting approach and a docking graft fixation technique are associated with the lowest complication rate and best patient outcomes.
Vitale et al. demonstrated that the flexor-pronator muscle-splitting approach was associated with better outcomes than detachment of the flexor-pronator mass, had a lower rate of postoperative ulnar neuropathy, and a lower overall complication rate. They also found fixation of the graft utilizing the docking technique was associated with better outcomes than the figure-of-8 technique. Abandoning the obligatory ulnar nerve transposition was associated with improved patient outcomes (89% vs. 75%) and a lower rate of postoperative ulnar neuropathy (4% vs. 9%).
Rettig et al performed a case series review of 31 overhead throwing athletes with ulnar collateral ligament injuries managed nonoperatively with 3 months rest followed by rehabilitation exercises. They concluded that 42% of athletes were able to return to their previous level of competition at an average of 6 months from diagnosis (earlier than reconstruction). The authors were unable to identify any patient-specific factors (duration of symptoms, age, acuity of onset) that would predict the success of nonoperative treatment.
In the docking graft fixation technique the graft is placed in a triangular configuration through a single humeral tunnel. The suture limbs are then brought out through two separate bone holes and tied over a bony bridge on the superior aspect of the medial epicondyle.
The figure-of-8 (Jobe) graft fixation technique is performed by passing the tendon graft through two bone tunnels in the medial epicondyle of the humerus and through one tunnel in the ulnar sublime tubercle. The graft is then sutured to itself in a figure-of-8 configuration.
Incorrect Answers:
Answer 1: The figure-of-8 technique is not associated with better patient outcomes when compared to the docking technique.
Answer 3: Obligatory ulnar nerve transposition during UCL reconstruction is associated with a higher rate postoperative ulnar neuropathy and worse patient outcomes, and therefore should be avoided.
Answers 4 and 5: Detachment of the flexor-pronator mass is not associated with better patient outcomes when compared to the muscle-splitting approach.
The medial ulnar collateral ligament, or medial collateral ligament of the elbow, is composed of three bundles:
- an anterior bundle
- a posterior bundle
- a variable transverse oblique bundle.
The anterior bundle of the ulnar collateral ligament is the primary restraint to valgus force of the elbow from 30 to 120 degrees of flexion.
Biomechanical testing has shown that valgus forces as high as 64 N.m at the elbow during late cocking and early acceleration phases of throwing with compressive forces of 500 N at the lateral radiocapitellar articulation as the elbow moves from 110 to 20 degrees of flexion and velocities as high as 3000 deg/sec.
Mechanisms of injury MUCL:
- Acute trauma: often associated with elbow dislocations
- Overuse injuries:
+ Microtrauma from repetitive valgus stress leads to rupture of anterior band of MUCL
+ Baseball pitchers place significant valgus stress on the elbow in the late cocking and early acceleration phase of throwing
+ elbow valgus load increases with poor throwing mechanics and decreases with trunk-scapular kinesis, forearm pronation, dynamic flexor-pronator stabilization
- Iatrogenic : excessive olecranon osteophyte resection places MCL at risk
A 25-year old female with a seizure disorder complains of persistent left shoulder pain after sustaining a seizure 1 week ago. She was placed in a sling in the ER and is following up in your office. Figure A shows the radiograph taken in the ER. On examination, her range of motion is limited and is only able to externally rotate to neutral. What is the next step in management?
Sling use for comfort and follow-up in 2 weeks
Repeat True AP radiograph
Axillary lateral radiograph
MRI of the shoulder
Intra-articular cortisone injection with range of motion exercises
Axillary lateral radiograph
This question tests the concept that posterior shoulder dislocation is frequently missed due to inadequate imaging. Trauma shoulder radiographs (which include an AP, axillary, and scapular Y view) must be obtained in all suspected shoulder dislocations.
Posterior dislocations are more common following a seizure. The posteriorly dislocated shoulder is typically held in IR and most consistent finding is a mechanical block to ER caused by the anterior humeral head defect on the posterior aspect of the glenoid.
According to the reference by Robinson et al, good functional outcomes are associated with early detection and treatment of isolated posterior dislocations that are associated with a small osseous defect and are stable following closed reduction.
Posterior shoulder instability and dislocations are less common than anterior shoulder instability and dislocations, but are much more commonly missed.
Diagnosis is made radiographically in the setting of acute dislocations. Chronic instability can be diagnosed with presence of positive posterior instability provocative tests and confirmed with MRI studies showing posterior labral pathology.
Treatment may be nonoperative or operative depending on chronicity of symptoms, recurrence of instability, and the severity of labrum and/or glenoid defects.
Risk factors for posterior dislocation include bony abnormality (glenoid retroversion or hypoplasia) and ligamentous laxity.
Mechanism:
Trauma - posterior dislocation - usually significant trauma.
Microtrauma - posterior instability - can lead to labral tear, incomplete labral avulsion or erosion of the posterior labrum which may lead to gradual stretching of the capsule and patulous posterior capsule - usually insidious onset and presentation.
Seizures and electric shock - tetanic muscles pull the humeral head out
Biomechanical forces: flexed, adducted and IR rotated arm = high risk position
Static restraint: labrum deepens glenoid by 50%
Primary stabilisers of posterior shoulder:
- Posterior band of IGHL: primary restraint in internal rotation
- Subscapularis: primary dynamic restraint in external rotation and against posterior subluxation
- Superior glenohumeral ligament and coracohumeral ligament: primary restraint to inferior translation of the adducted arm and to external rotation and primary static stabilizer to posterior subluxation with shoulder in flexion, adduction, and internal rotation.
Acute posterior dislocation -> limited external rotation, with the arm locked in an IR position. Pain on flexion, adduction and IR for posterior instability.
Provocative tests:
- Jerk test
- Kim test
- Posterior stress test
- Posterior load and shift test
A 62-year-old man complains of shoulder pain for 2 years. He has had 1 course of intra-articular sodium hyaluronate and 6 weeks of physical therapy with little relief. Examination reveals diminished arm flexion and abduction secondary to pain. Radiographs of his shoulder are shown in Figures A and B. According to the American Academy of Orthopaedic Surgeons Clinical Practice Guidelines, what is the next best step?
XR: end stage GHJ OA
Humeral head replacement arthroplasty
Hemiarthroplasty and ream-and-run glenoid procedure
Cuff tear arthropathy (CTA) prosthesis
Total shoulder arthroplasty with a metal-backed cemented glenoid component
Total shoulder arthroplasty with an all-polyethylene cemented glenoid component
Total shoulder arthroplasty with an all-polyethylene cemented glenoid component
This patient has end-stage glenohumeral osteoarthritis (GH OA). According to the AAOS CPG, total shoulder arthroplasty (TSA) is recommended using an all-polyethylene cemented glenoid component.
TSA is indicated for cases of end-stage GH OA. It is preferred to hemiarthroplasty. It is contraindicated in cases with insufficient glenoid bone stock (glenoid wear to the level of the coracoid), rotator cuff arthropathy or irreparable cuff tears and deltoid dysfunction. It provides good pain relief and has good survival at 10 years (>90%).
Figures A and B show end-stage GH OA with large osteophytes and subchondral sclerosis. There is significant glenoid wear and posterior subluxation (Walch B glenoid deformity).
Incorrect Answers:
Answer 1: The AAOS CPG does not recommend humeral head replacement arthroplasty (resurfacing).
Answer 2: Although the AAOS CPG recommends both hemiarthroplasty and TSA as options, TSA is preferred.
Answer 3: The AAOS CPG does not recommend use of a CTA humeral component.
Answer 4: The AAOS CPG does not recommend the use of metal-backed glenoid components. Metal-backed glenoids have higher rates of revision than all-polyethylene glenoids.
TSA:
Replacement of humeral head and glenoid resurfacing: cemented all-polyethylene glenoid resurfacing is standard of care
Total shoulder arthroplasty unique from THA and TKA in that:
- Greater range of motion in the shoulder
- Success depends on proper functioning of the soft tissues
- Glenoid is less constrained: leads to greater sheer stresses and is more susceptible to mechanical loosening
Factors required for success of TSA
- Rotator cuff intact and functional: if rotator cuff is deficient and proximal migration of humerus is seen on x-rays (rotator cuff arthropathy) then glenoid resurfacing is contraindicated. If there is an irreparable rotator cuff deficiency then proceed with hemiarthroplasty or a reverse ball prosthesis. An isolated supraspinatus tear without retraction can proceed with TSA - incidence of full thickness rotator cuff tears in patients getting a TSA is 5% to 10% - if positive impingement signs on exam, order a pre-operative MRI.
- Glenoid bone stock and version
if glenoid is eroded down to coracoid process then glenoid resurfacing is contraindicated (Walch classification).
Outcomes
Pain relief more predictable than hemiarthroplasty, reliable range of motion, good survival at 10 years (93%), good longevity with cemented and press-fit humeral components, worse results for post-capsulorrhaphy arthropathy.
Indications
- Pain (anterior to posterior), especially at night, and inability to perform activities of daily living
- Glenoid chondral wear to bone: preferred over hemiarthroplasty for osteoarthritis and inflammatory arthritis
- Posterior humeral head subluxation
Contraindications
- Insufficient glenoid bone stock
- Rotator cuff arthropathy
- Deltoid dysfunction
- Irreparable rotator cuff (hemiarthroplasty or reverse total shoulder are preferable) as risk of loosening of the glenoid prosthesis is high (“rocking horse” phenomenon)
- Active infection
- Brachial plexus palsy
Glenoid loosening - most common cause of TSA failure (30% of primary OA revisions)
Risk factors: insufficient glenoid bone stock (posterior glenoid wear associated with glenoid loosening), rotator cuff deficiency
2.9% reoperation rate for loosening (28% with revision)
Vascular injury
Arcuate artery, branch off the anterior humeral circumflex artery, can be damaged during biceps tendon elevation
Humeral stem loosening: more common in RA and osteonecrosis. Rule out infection.
Subscapularis repair failure
Malposition of components
Improper soft tissue balancing: failure due to undiagnosed presence of rotator cuff tears
Iatrogenic rotator cuff injury can occur if humeral neck osteotomy is inferior to level of rotator cuff insertion. Overstuffing glenohumeral joint leading to attritional supraspinatus and subscapularis tears
Stiffness
Infection: may have normal aspiration results
culture. Infection rate 1-2% after primary TSA.
Arthroscopic tissue culture more sensitive (100% sensitive and specific) than fluoroscopically guided aspiration (17% sensitivity, 100% specific)
Propionibacterium acnes (P. acnes),
now referred to as Cutibacterium acnes (c. acnes) most common cause of indolent infections and implant failures - gram positive, facultative, aerotolerant, anaerobic rod that ferments lactose to propionic acid
has high bacterial burden around the shoulder forms biofilm.
P. acnes PJI more common in males
Use anaerobic culture bottles, keep for 10-14days (mean time to detection 6 days)
Neurologic injury: axillary nerve is most commonly injured, musculocutaneous nerve can be injured by retractor placement under conjoint tendon
Periprosthetic fracture: acceptable fragment alignment ≤ 20° flexion/extension, ≤ 30° varus/valgus, ≤ 20° rotation malalignment
Wright and Cofield system:
Type A fractures are proximal to the stem tip and are treated with ORIF;
Type B fractures are at the level of the stem tip and are treated with ORIF;
Type C fractures are distal to the stem tip and can be initially treated nonoperatively.
Steinmann et al. reviewed the treatment of periprosthetic humeral shaft fractures.
For intraoperative fractures, the authors recommended placement of a long stem prosthesis that bypasses the fracture site by at least 2 cortical diameters.
For postoperative type A and B fractures, treatment depends on whether the stem is loose or well fixed. Loose prostheses necessitate revision long stem component with supplementary fixation, whereas well-fixed stems require hybrid plate fixation. Type C fractures can be treated non-operatively, but in the presence of nonunion may require plate fixation with or without allograft struts.
During a total shoulder arthoplasty (TSA), which of the following technical maneuvers would most likely place the rotator cuff tendons at risk of injury?
Excessive retraction on the deltoid muscle during a delto-pectoral approach
Palpation of the rotator cuff insertion prior to humeral head resection
A humeral cut with 30 degrees of retroversion
Excessive bone removal with the humeral neck osteotomy
A humeral cut with 45 degrees of inclination
Excessive bone removal with the humeral neck osteotomy
The rotator cuff tendons can be inadvertantly cut or detached during a TSA if the head cut is made either too distally or in excessive retroversion.
Pearl et al studied the placement of humeral component position during TSA by studying 21 cadaveric specimens they recommend anatomic reconstruction of the retroversion angle based on patient anatomy. They also stress palpation of the rotator cuff insertion prior to humeral head resection to avoid inadvertant cuff injury.
Appropriate osteotomy is made proximal to both the greater and less tuberosities and medial to SIT insertion.
Incorrect Answers:
Choice 1- Excessive retraction on the deltoid muscle could cause injury to the axillary nerve, but will not injure the rotator cuff.
Choices 2- This step is encouraged to spare the rotator cuff insertions before humeral head osteotomy
Choice 3- A head cut in 30 degrees of retroversion is normal
Choice 5- Excessive inclination may take too much medial bone, but if appropriately placed, would not risk injuring the rotator cuff insertion.
TSA:
Replacement of humeral head and glenoid resurfacing: cemented all-polyethylene glenoid resurfacing is standard of care
Total shoulder arthroplasty unique from THA and TKA in that:
- Greater range of motion in the shoulder
- Success depends on proper functioning of the soft tissues
- Glenoid is less constrained: leads to greater sheer stresses and is more susceptible to mechanical loosening
Factors required for success of TSA
- Rotator cuff intact and functional: if rotator cuff is deficient and proximal migration of humerus is seen on x-rays (rotator cuff arthropathy) then glenoid resurfacing is contraindicated. If there is an irreparable rotator cuff deficiency then proceed with hemiarthroplasty or a reverse ball prosthesis. An isolated supraspinatus tear without retraction can proceed with TSA - incidence of full thickness rotator cuff tears in patients getting a TSA is 5% to 10% - if positive impingement signs on exam, order a pre-operative MRI.
- Glenoid bone stock and version
if glenoid is eroded down to coracoid process then glenoid resurfacing is contraindicated (Walch classification).
Outcomes
Pain relief more predictable than hemiarthroplasty, reliable range of motion, good survival at 10 years (93%), good longevity with cemented and press-fit humeral components, worse results for post-capsulorrhaphy arthropathy.
Indications
- Pain (anterior to posterior), especially at night, and inability to perform activities of daily living
- Glenoid chondral wear to bone: preferred over hemiarthroplasty for osteoarthritis and inflammatory arthritis
- Posterior humeral head subluxation
Contraindications
- Insufficient glenoid bone stock
- Rotator cuff arthropathy
- Deltoid dysfunction
- Irreparable rotator cuff (hemiarthroplasty or reverse total shoulder are preferable) as risk of loosening of the glenoid prosthesis is high (“rocking horse” phenomenon)
- Active infection
- Brachial plexus palsy
Glenoid loosening - most common cause of TSA failure (30% of primary OA revisions)
Risk factors: insufficient glenoid bone stock (posterior glenoid wear associated with glenoid loosening), rotator cuff deficiency
2.9% reoperation rate for loosening (28% with revision)
Vascular injury
Arcuate artery, branch off the anterior humeral circumflex artery, can be damaged during biceps tendon elevation
Humeral stem loosening: more common in RA and osteonecrosis. Rule out infection.
Subscapularis repair failure
Malposition of components
Improper soft tissue balancing: failure due to undiagnosed presence of rotator cuff tears
Iatrogenic rotator cuff injury can occur if humeral neck osteotomy is inferior to level of rotator cuff insertion. Overstuffing glenohumeral joint leading to attritional supraspinatus and subscapularis tears
Stiffness
Infection: may have normal aspiration results
culture. Infection rate 1-2% after primary TSA.
Arthroscopic tissue culture more sensitive (100% sensitive and specific) than fluoroscopically guided aspiration (17% sensitivity, 100% specific)
Propionibacterium acnes (P. acnes),
now referred to as Cutibacterium acnes (c. acnes) most common cause of indolent infections and implant failures - gram positive, facultative, aerotolerant, anaerobic rod that ferments lactose to propionic acid
has high bacterial burden around the shoulder forms biofilm.
P. acnes PJI more common in males
Use anaerobic culture bottles, keep for 10-14days (mean time to detection 6 days)
Neurologic injury: axillary nerve is most commonly injured, musculocutaneous nerve can be injured by retractor placement under conjoint tendon
Periprosthetic fracture: acceptable fragment alignment ≤ 20° flexion/extension, ≤ 30° varus/valgus, ≤ 20° rotation malalignment
Wright and Cofield system:
Type A fractures are proximal to the stem tip and are treated with ORIF;
Type B fractures are at the level of the stem tip and are treated with ORIF;
Type C fractures are distal to the stem tip and can be initially treated nonoperatively.
Steinmann et al. reviewed the treatment of periprosthetic humeral shaft fractures.
For intraoperative fractures, the authors recommended placement of a long stem prosthesis that bypasses the fracture site by at least 2 cortical diameters.
For postoperative type A and B fractures, treatment depends on whether the stem is loose or well fixed. Loose prostheses necessitate revision long stem component with supplementary fixation, whereas well-fixed stems require hybrid plate fixation. Type C fractures can be treated non-operatively, but in the presence of nonunion may require plate fixation with or without allograft struts.
A 26-year-old accountant has recurrent shoulder instability. His first dislocation occurred after a fall while skiing. He has now sustained his third dislocation, which was reduced in the emergency department prior to being sent to your office. What is the most appropriate definitive treatment?
FIGURES: A : CT recon showing small (~10%) bony defect on anterior glenoid.
Immobilization in external rotation for 6 weeks
Arthroscopic bony Bankart repair
Arthroscopic Remplissage procedure
Glenoid augmentation using coracoid transfer
Glenoid augmentation using tricortical iliac crest graft
Arthroscopic bony Bankart repair
This patient has recurrent shoulder instability with a small bony defect of the anterior glenoid and no previous surgery. The most appropriate definitive management in this patient would be arthroscopic bony Bankart repair.
Figure A shows an en face sagittal 3D reconstruction of a glenoid with 10% surface area loss.
Older (>20 years old), recreational athletes with minor glenoid bone loss (<20% of the glenoid surface area) may be treated with soft tissue stabilization procedures using suture anchors. Goals of this procedure include tightening and repairing the torn ligament and labrum to the glenoid. Younger, contact sports athletes with large glenoid defect (>20%) may require bony augmentation type of procedures.
Defects larger than 25% of glenoid width should be managed with bony augmentation, with soft-tissue stabilization in smaller defects.
Following Bankart procedure risk factors for failure: age <=20, competitive participation in contact sports, shoulder hyperlaxity, Hill-Sachs on AP radiograph, glenoid bone loss of contour on AP radiograph.
The MOON Shoulder Group compared radiography, MRI and CT to determine the most reliable imaging modality for predicting bone loss. Three-dimensional CT, followed by regular CT were the most reliable and reproducible imaging modalities for predicting glenoid bone loss.
Incorrect Answers:
Answer 1: While closed reduction and immobilization are appropriate initial management, after failing conservative management, definitive management for recurrent shoulder dislocation is surgical.
Answer 3: Remplissage procedure is indicated in setting of large Hill-Sachs lesions.
Answers 4 & 5: Glenoid augmentation procedures using coracoid transfer (Bristow-Latarjet) and tricortical iliac crest graft would be indicated in setting of larger glenoid bone loss.
Arthroscopic Bankart Repair +/- capsular plication:
- Relative implications: 1st time dislocation with Bankart on MRI in athlete <25 years, high demand athletes, recurrent dislocation/subluxation (>1 dislocation) following non-operative management <20-25% bone loss, remplissage augmentation with arthroscopic Bankart may be considered if Hills-Sachs “off-track”.
Technique: at least 3 anchor points should be used, paramount that labrum is fully mobilised prior to repair.
Equal outcomes to open repair with advantage of less pain and greater motion preservation.
Failure rates increased in patients with global hyper laxity, glenoid bone loss or too few fixation points.
Laterjet (coracoid transfer) or Bristow Procedure:
- For chronic bony deficiencies with >20-25% glenoid deficiency (inverted pear deformity to glenoid).
- Transfer of coracoid bone with attached conjoined tendon and CA ligament
- Laterjet has the triple effect = bony (increases glenoid track), sling (conjoined tendon on top of subscap), capsule reconstruction (CA ligament)
- Deltopectoral approach, split subscap
Consider autograft (tri-cortical Iliac crest or distal clavicle) or allograft (iliac crest or distal tibia) for bony deficiencies with >20-25% glenoid deficiency (inverted pear deformity to glenoid) and revision of failed latarjet. Can be performed arthroscopic or open.
Remplissage and Bankart Repair:
- For engaging large (>25-40%) Hill-Sach or ‘off-track’ Hill-Sach lesion with <20-25% glenoid bone loss
- Technique: posterior capsule and infraspinatus tendon is sutured into the Hill-Sach lesion, may be performed with concomitant Bankart repair. By decreasing size of Hill-Sach, converts off-track lesion into on-track lesion.
When compared to latarjet at 2 years, replissage and Bankart has lower recurrent instability rates (1.4% vs 3.2%) despite greater bipolar bone loss.
Bone graft recon for Hill-Sachs Defect
- For engaging large (>40%) Hill-Sach lesion
Technique: allograft reconstruction, arthroplasty, rotational osteotomy
Consider tendon transfer for chronic irreparable subscapularis tears (lat dorsi or sternal head of pec major)
A patient with shoulder pain and weakness has an MRI showing a cyst in the suprascapular notch. Which of the following muscles is most likely to show weakness?
Deltoid Supraspinatus Supraspinatus and infraspinatus Infraspinatus Teres minor
Supraspinatus and infraspinatus
The suprascapular notch is proximal to the point where the suprascapular nerve innervates both the supraspinatus and the infraspinatus, therefore compression would cause weakness of both.
Compression at the spinoglenoid notch will affect only the infraspinatus as the suprascapular nerve has already innervated the supraspinatus by this point. The teres minor and deltoid are both innervated by the axillary nerve. The axillary nerve passes through the quadrangular space and compression here could result in denervation of the posterior deltoid. Spinoglenoid notch cysts are classically seen in volleyball players and associated with SLAP tears.
Martin et al review the outcomes of 24 overhead athletes who underwent arthroscopic debridement of labral tears. Results were good to excellent in 21 of the 24 patients when there was no gross instability or Bankart lesion present.
Meister et al review the evaluation and treatment of the throwing athlete. Rotator cuff weakness, labral tears and paralabral cysts are discussed. Treatment is based on the pathoanatomy of the throwing shoulder, and most athletes will achieve successful rehabilitation with nonoperative care.
Suprascapular neuropathy is compression of the suprascapular nerve that most commonly occurs at the suprascapular notch or spinoglenoid notch by a mass (i.e cyst).
Diagnosis can be suspected clincally with weakness and atrophy of the infraspinatous or supraspinatous and confirmed with MRI studies showing cysts in the suprascapular notch or spinoglenoid notch.
Treatment of suprascapular nerve compression at the suprascapular notch requires decompression of a cyst when present. Treatment of a spinoglenoid cyst requires either decompression or repair of an associated labral lesion (if present).
Suprascapular notch entrapment:
Proximal compression of supra scapular nerve in the supra scapular notch leads to weakness of both supraspinatus and infraspinatus. Suprascapular nerve (C5,6) - emerges off superior trunk of brachial plexus, travels across posterior triangle of neck to scapula innervation of supraspinatus and infraspinatus. Compression can be due to a ganglion cyst (often associated with labral tears), transverse scapular ligament entrapment, fracture callus.
Spinoglenoid notch entrapment:
Distal compression of supra scapular nerve therefore weakness of infraspinatus only. Compression can be due to posterior labral tears -> cyst, spinoglenoid ligament, spinoglenoid notch ganglion, traction injury (volleyball players), transglenoid fixation
Suprascapular ligament arises from medial base of coracoid and overlies suprascapular notch - suprascapular artery runs above and suprascapular nerve runs below.
Spinoglenoid ligament arises near spinoglenoid notch and overlies distal suprascapular nerve
