Difference between revisions of "Posterosuperior Rotator Cuff Tears and Associated Pathologies"

Revision as of 14:11, 3 January 2020

1 Bullet Points
2 Key Words
3 Biomechanics of the Posterosuperior Rotator Cuff
4 Clinical examination
- 4.1 Supraspinatus
- 4.2 Infraspinatus and Teres Minor
  - 4.2.1 Strength in External Rotation Elbow at the Side
  - 4.2.2 External Rotation Lag Sign
5 Imaging
6 Classification
7 Irreparable Rotator Cuff Tears
8 References

Bullet Points

The rotator cable explains why patients with most rotator cuff tears can maintain active forward flexion, and also why even after only a partial rotator cuff repair, good functional results can be achieved.
The most important negative prognostic factor is high-grade fatty infiltration of the rotator cuff muscle bellies (grade 3 or 4 fatty infiltration).
The tangent sign is an indicator of advanced fatty infiltration and is a predictor of whether a rotator cuff tear will be reparable.
Full thickness disruption of the lateral tendon stump (B1) is the most frequent type of rotator cuff lesion, comprising approximately 90% of all surgically treated lesions.
Musculotendinous junction lesions (C-type) or rare and characterized by an edema of the muscle belly. They are associated to calcific deposit (infraspinatus) or trauma (supraspinatus). Unrepaired, grade III lesions lead rapidly to grade 4 fatty infiltration of the muscle.
Tendon retraction is classified according to Patte. Overreduction and lateral transposition of the tendon over the greater tuberosity may be unphysiological.
Massive rotator cuff has different definitions in the literature, each having potential benefits or drawbacks.
Massive rotator cuff tears comprise approximately 20% of all cuff tears and 80% of recurrent tears.
The classification of Collin not only subclassifies massive tears but has also been linked to function, particularly the maintenance of active elevation.
Non-surgical treatment is effective in patient with massive rotator cuff if the tear involves less than three tendons and do not involves the subscapularis (D-type).
Biomechanical testing has consistently demonstrated the superiority of double-row constructs over single-row. However, there is no obvious difference clinically.
There is actually no support for routine suprascapular nerve release when massive rotator cuff repair is performed.
Functional outcome improved after revision rotator cuff repair and 70% or more of patients were satisfied or very satisfied. However, the prevalence of persistent defect (retear or non-healing) is 28% at six months and 40% at two years.
Rotator cuff are irreparable when associated to true pseudoparalysis with the presence of lag signs (external rotation lag, drop, dropping, hornblower signs), femoralization of the humerus or acetabulization of the acromion, grade 3 or 4 fatty infiltration and tangent sign.
The current literature does not support the initial use of complex and expensive techniques in the management of posterosuperior irreparable rotator cuff tears.

Key Words

Shoulder arthroscopy; Rotator cuff lesion; Partial repair; Tear pattern; Classification; Massive; Reparable and non-repairable; Irreparable; Imaging; Recurrent; Failed; Revision surgery; Open and arthroscopic approach; Conservative or non-operative treatment; Physiotherapy; Functional outcomes; Prognostic factors; Latissimus dorsi transfer; Subacromial spacer interposition; Balloon; Biceps tenotomy; Superior capsular reconstruction; Reverse arthroplasty; Magnetic resonance imaging (MRI) arthrography (MRA); Fosbury flop tear; New tear pattern; FUSSI; SAM.

Biomechanics of the Posterosuperior Rotator Cuff

A primary function of the rotator cuff is to work synergistically with the deltoid to maintain a balanced force couple about the glenohumeral joint. A force couple is a pair of forces that act on an object and tend to cause it to rotate. For any object to be in equilibrium, the forces must create moments about a center of rotation that are equal in magnitude and opposite in direction. Coronal and transverse plane force couples exist between the subscapularis anteriorly and infraspinatus and teres minor posteriorly. The rotator cuff force across the glenoid provides concavity compression, which creates a stable fulcrum and allows the periscapular muscles to move the humerus around the glenoid.

The rotator cable is a thickening of the rotator cuff that has been likened to a suspension bridge in which force is distributed through cables that are supported by pillars (the anterior and posterior attachments). The anterior rotator cable attachment bifurcates to attach to bone just anterior and posterior to the proximal aspect of the bicipital groove. The posterior attachment comprises the inferior 50% of the infraspinatus. With small central tears the cable attachments often stay intact and forces are transmitted along the rotator cable. The rotator cable also explains why patients with most rotator cuff tears can maintain active forward flexion, and also why even after only a partial rotator cuff repair, good functional results can be achieved.^[1]

However, in the setting of massive rotator cuff with rotator cable disruption and non-compensation by other humeral head stabilizers (i.e pectoralis major and latissimus dorsi), the moments created by the opposing muscular forces are insufficient to maintain equilibrium in the coronal plane, resulting in altered kinematics, instability, and ultimately in pseudoparalysis. Interestingly, only few patients with an irreparable rotator cuff tears developed pseudoparalysis and arthritis.This finding has at least two potential explanations. First, the subscapularis that may not be involved in these tears is the key factor of active forward flexion.^[2]

Second, the rotator cable, has still an intact anterior attachment which is important for elevation. This may explain why patients can maintain active mobility, and also why even after only a partial rotator cuff repair, good functional results can be achieved.^[3]

Consequently, all the conditions for an imbalance in the force couples are not always met and subsequently loss of function is only occasionally seen.

Clinical examination

Supraspinatus

Superior rotator cuff insufficiency, present in complete tears, is usually associated with a positive Jobe manoeuver and decreased strength in the external resistance of the elbow at the side.^[4]

Figure. 1 Jobe manoeuver: the examiner push both arms down at the level of the wrists. Reproduce from Liotard J, Walch G. Test de Jobe. Recherche d'une atteinte du tendon supraépineux. In: Rodineau J, ed. 33 tests incontournables en traumatologie du sport. Paris: Éd. scientifiques; 2009, with permission.

Testing of abduction strength in the champagne toast position, i.e., 30° of abduction, mild external rotation, and 30° of flexion, better isolates the activity of the supraspinatus from the deltoid than Jobe's “empty can” position (Figure).^[5]

Figure. 2 Testing at 30° of abduction, 30° of forward elevation, 90° of elbow flexion, and mild external rotation replicates a “toast” position.

Infraspinatus and Teres Minor

Strength in External Rotation Elbow at the Side

Strength in external rotation elbow at the side of the supraspinatus, infraspinatus and teres minor represents approximately 10%, 70% and 20% of total external rotation strength, respectively.^[6]

However, the function of the teres minor may become more important in the setting of a chronic infraspinatus tear, as its hypertrophy is commonly observed in these cases and probably compensates for external rotation weakness.

External Rotation Lag Sign

The external rotation lag sign (Figure and Video), described by Hertel, was designed to test the integrity of infraspinatus and supraspinatus tendons.^[7]

The extent of internal rotation is recorded to the nearest 10 degrees degrees (10, 20, 30 and 40 degrees or above). An external rotation lag sign > 40 degrees seems to be the most reliable test for the teres minor.^[8]

Figure. 3 A) The external rotation lag sign is performed seated with the elbow flexed to 90 degrees and the shoulder elevated 20 degrees in the scapular plane. The arm is passively taken to maximal external rotation minus 5 degrees to allow for elastic recoil. B) The patient was asked to maintain that position as the clinician released the wrist. A positive test is defined as any internal rotation of more than 10 degrees. Reproduce from Collin et al., with permission.

Drop Sign

The drop sign (Figure and Video), also described by Hertel, is designed to assess the function of the infraspinatus.

Figure. 4
A) The drop sign is a lag sign beginning from 90 degrees of abduction in the scapular plane, with elbow flexion of 90 degrees, and external rotation of the shoulder to 90 degrees. From this position, the patient is asked to maintain the position against gravity (MRC Grade 3).
B) Failure to resist gravity and internal rotation of the arm is considered a positive drop sign. Reproduce from Collin et al., with permission.

Hornblower sign

The patient is asked to bring both hands to his mouth, but is unable to do so without abducting the affected arm (Video).

Patte Test

The Patte test (Figure and Video) is the only test that allowed to analyze the muscular strength of the teres minor in case of deficient infraspinatus.^[9]

Figure. 5
A) The Patte test is performed by passively taking from a starting point of 90 degrees of abduction in the scapular plane, an elbow flexion of 90 degrees without external rotation.
B) The patient is asked to perform external rotation of the shoulder from this position against resistance. A positive Patte test is defined as external rotation power less than MRC Grade 4. Reproduce from Collin et al., with permission.

Walch et al. reported a 100% sensitivity and 93% specificity with the Patte test and teres minor fatty atrophy Grade 3 or greater.^[10]

Dropping Sign

The dropping sign of Neer had a 100% sensitivity and 66% specificity for teres minor involvement.^[11]^[12]

Imaging

X-rays

The analysis should always begin with plain radiographic views to determine the morphology and status of the glenohumeral joint to exclude glenohumeral arthritis:

Anteroposterior True anteroposterior X-ray with the arm in neutral rotation, and the patient relaxed is obtained to evaluate the shape of the acromion and greater tuberosity, the critical shoulder angle, and the acromiohumeral distance. A decreased acromiohumeral distance < 7 mm in a standard antero-posterior radiograph indicates superior migration of the humeral head which increases the probability of finding an irreparable cuff tear. Such distance is correlated to 1) tears of the infraspinatus that mainly acts in lowering the humeral head, and 2) varying degrees of fatty infiltration.^[13]^[14]

Nevertheless, such criteria should be interpreted with parsimony. First, it is difficult in clinical practice to obtain standardized X-rays making measurement aleatory. Second, this distance has not been associated with an inability to obtain an intra-operative complete repair of the supraspinatus (18.2% irreparable, OR = 0.55, P = 0.610).^[15]

At the end of the spectrum, acetabularization of the acromion and femoralization of the humeral head are pre-operative adapting factors reflecting significant chronic static superior instability and are a contraindication for repair.

Lateral Y-view (Lamy)

Lateral Y-view (Lamy) is used to analyze the presence of a spur, the shape of the acromion on this view is less accurate to detect full-thickness rotator cuff tear.^[16]

Axillary lateral

An axillary lateral view can exclude static anterior subluxation or os acromialis.

If pathology of the acromioclavicular joint is suspected, a Zanca view is additionally acquired.^[17]

Ultrasound (US)

Following X-ray evaluation, advanced imaging modalities are obtained to confirm and plan treatment. Ultrasonography is an excellent cost-effective screening tool in the office but does not allow evaluation of intra-articular pathology or easy evaluation of muscle quality.

Rotator Cuff Interval

The space through which the long head of the biceps passes as it leaves the glenohumeral joint is called the rotator cuff interval. The patient position is the same as for evaluation of the long head of the biceps, with the probe being placed slightly superiorly to the bicipital groove and in the axial plane (Figure). The long head of the biceps is thus visualized with the subscapularis medially and the supraspinatus laterally, while the coracohumeral and superior glenohumeral ligaments surround it.^[18]

Figure. 6 Rotator cuff interval, containing the long head of the biceps, with a longitudinal view of the subscapularis medially and transverse view of the supraspinatus laterally, while the coracohumeral and superior glenohumeral ligaments surround it. Ultrasound image (a) with superimposed anatomy (b) and patient/probe position (c). Reproduced from Plomb-Holmes et al., with permission.

Supraspinatus Tendon and Subacromial-Subdeltoid Bursa

The supraspinatus tendon is best visualized with the shoulder in abduction and internal rotation, by asking the patient to place the palm of their hand on their back pocket, elbow pointed backwards (Figure). In patients presenting with reduced range of motion (adhesive capsulitis for example), maximal internal rotation with the arm hanging by the side of the thorax can be sufficient. The long axis of the tendon is most useful for analyzing integrity of the tendon on the footprint (measuring approx. 2 cm medially to laterally), and is visualized by holding the probe in a tilted position (therefore not a true coronal plane but at an approx. 45 degree angle, following the line of the humerus (Figure)).

This position also allows visualization of two other structures: the subacromial-subdeltoid bursa (and the presence of excessive liquid, see below) and the humeral head along with its articular cartilage (and possible surface defects). In the axial plane (again not truly axial but at 90 degrees to the previous plane), the leading edge of the supraspinatus can be identified laterally to the biceps tendon. Moving the probe laterally will reveal the mid-portion of the tendon, with the anterior part of the infraspinatus eventually coming into view as an anisotropic and dark image (as the fibers run in a different plane).

Figure. 7 Supraspinatus tendon, visualized on its longitudinal axis, and the subacromial-subdeltoid bursa lying superficially to it.
Ultrasound image (a) with superimposed anatomy (b), patient/probe position (c), and landmarks for measurement of these two structures (d). Reproduced from Plomb-Holmes et al., with permission

Infraspinatus and teres minor tendon, glenohumeral joint, spinoglenoid notch

The infraspinatus tendon, which inserts posteriorly to the supraspinatus tendon, is best examined in its long axis by elongating it (the patient placing his or her hand on the opposite shoulder) and placing the probe on the posterior part of the patient’s shoulder (Figure). The insertion of the tendon on the humeral head can be analyzed, as well as the musculotendinous junction by sliding the probe medially. At this point, the glenohumeral joint line and posterior labrum can be visualized in thin patients, and even more medially, the spinoglenoid notch containing the suprascapular neurovascular bundle (and the possible presence of a ganglion cyst arising from the posterior labrum which can compress the bundle) (Figure). The teres minor tendon can be difficult to separate from the infraspinatus tendon; it is located inferiorly and has a similar aspect, but can be distinguished by the fact that deeper to it lies bone whereas the infraspinatus lies on articular cartilage, and its insertion is primarily muscular (vs. tendinous).

Figure. 8 Infraspinatus tendon, visualized on its longitudinal axis. Ultrasound image (a) with superimposed anatomy (b) and patient/probe position (c). Reproduced from Plomb-Holmes et al., with permission.

Magnetic Resonance Imaging (MRI) and Computer Tomography (CT)

Magnetic resonance imaging accurately estimates tear pattern, muscle fatty infiltration and atrophy, tendon length and retraction, and is thus obtained to plan repair or reconstructive surgeries. The muscle bellies of the rotator cuff are assessed, if available, on T1-weighted axial, coronal, sagittal views with cuts sufficiently medial on the scapula to allow proper assessment regardless of retraction. Finally, computer tomography (CT) scans are used if magnetic resonance imaging is contraindicated or if joint replacement is planned, particularly in the setting of glenoid deformity. Additionally, computer tomography (CT) scan can be conducted with intra-articular contrast to assess the cuff. It should be noted that the magnetic resonance imaging and computer tomography are not reliable to analyze the acromiohumeral distance as they are performed in lying position.

Fatty Infiltration

The most important negative prognostic factor is high-grade fatty infiltration of the rotator cuff muscle bellies (grade 3 or 4 fatty infiltration) (Figure).

Figure. 9 Sagittal view of a left shoulder computed tomography (CT) arthrogram that show a Grade 4 fatty infiltration of infraspinatus and teres minor.

Fatty infiltration is irreversible even with repair and leads to reduced function of the rotator cuff musculature.^[19]
If pathology of the acromioclavicular joint is suspected, a Zanca view is additionally acquired.^[20]^[21]^[22]

Atrophy

The presence or absence of supraspinatus atrophy is determined using the tangent sign of Zanetti et al. (Figure).^[23]

Figure. 10 The “tangent” sign is used on sagittal images. A is a line (in red) which is drawn at a tangent to the superior border of the scapular spine and the superior margin of the coracoid on the most lateral image where the scapular spine is in contact with the scapular body: a) negative tangent sign; b) positive tangent sign. Reproduced from Lädermann A, Collin P, Athwal GS, Scheibel M, Zumstein MA, Nourissat G. Current concepts in the primary management of irreparable posterosuperior rotator cuff tears without arthritis. EFORT Open Rev 2018;3:200-9, with permission.

This sign is an indicator of advanced fatty infiltration and has been reported to be a predictor of whether a rotator cuff tear will be reparable.^[24]^[25]
An inability to obtain a complete repair of the supraspinatus is associated with a positive tangent sign (30% irreparable) versus a negative tangent sign (6.3% irreparable, OR = 6,3, P =0.0102).^[26]
Supraspinatus atrophy can also be determine according to Thomazeau classification.^[27]
Agreement for this classification is however fair (intra-observer kappa = 0,51 and inter-observer kappa = 0.30) and its use cannot be recommended as a criteria of reparability.^[28]

Classification

Reproduced from Lädermann A, Burkhart SS, Hoffmeyer P, et al. Classification of full-thickness rotator cuff lesions: a review. EFORT Open Rev 2016;1:420-30, with permission

The rotator cuff lesions are categorized into four major groups based on involvement of the bone (Type A), tendon (Type B), musculotendinous junction (Type C) or muscle insufficiency (Type D).

Type A: Bony Involvement

While the majority of rotator cuff lesions involve the tendinous insertion, bony involvement is an important consideration. Bony involvement includes acute fractures, malunion/nonunion, and chronic bony insufficiency.

A1. Acute Bony Involvement (Fractures and Avulsions)

Isolated greater tuberosity fractures are considered uncommon, representing less than 5% of all operatively treated proximal humeral fractures.^[29]

Isolated lesser tuberosity fractures are generally considered rare. Type A lesion of the greater or lesser tuberosity represent approximately 3.2% and 1.1% respectively of surgically treated rotator cuff lesions (Table). Tuberosity fractures are included in the accepted classification for proximal humeral fractures by Neer, in itself a modification of Codman’s original description. Because the greater and lesser tuberosity are the insertion site of the rotator cuff, even small tuberosity fractures or avulsions can represent substantial disruption of the rotator cuff and lead to functional impairment if displaced and left untreated. Historically, Neer proposed 10 mm of displacement as a threshold for operative intervention.^[30]

However, more recent investigation has recommended that a threshold of 5 mm31 should be used.^[31]

Displacement of greater than 5 mm can lead to bony impingement with loss of range of motion as well as loss of strength from compromise in the normal length–tension relationship of the rotator cuff. A traumatic mechanism is typical such as violent muscular contraction, impaction of the greater tuberosity beneath the acromion, or shearing against the anterior glenoid rim during a glenohumeral dislocation event. Thorough patient evaluation is required to make an appropriate treatment recommendation. Conservative therapy is limited to non- or minimally-displaced fractures. The ongoing development of arthroscopic techniques has led to multiple reports about arthroscopically assisted or total arthroscopic techniques in the treatment of these injuries.^[32]

A.2 Tuberosity Malunion/Nonunion

Tuberosity malunion or nonunion can be a sequela of either conservative treatment or surgical treatment of acute injuries. As noted previously, displacement effectively shortens the muscle-tendon unit such that the rotator cuff cannot function properly (Figures).

Figure. 11 Schema of tuberoplasty for varus malunion of surgical neck fracture. (A) Intact proximal humerus. (B) Varus malunion results in a medialized greater tuberosity and effectively decreases the resting tension in the rotator cuff. As a result, force generation is compromised. (C) The rotator cuff is detached, and a tuberoplasty is performed with a burr. (D) Reattachment of the rotator cuff laterally results in restoration of the rotator cuff length–tension relation. Reproduce from Lädermann et al., with permission.

Figure. 12 Schema of tuberoplasty for valgus malunion of 3-part proximal humeral fracture. (A) Intact proximal humerus. (B) Valgus impaction results in superior displacement of the greater tuberosity and effectively decreases the resting tension in the rotator cuff. As a result, force generation is compromised. (C) The rotator cuff is detached, and a tuberoplasty is performed with a burr. (D) Reattachment of the rotator cuff laterally results in restoration of the rotator cuff length– tension relation. Reproduce from Lädermann et al., with permission.

Various open techniques have been described for the management of the malunion of proximal humeral fractures, including prosthetic reconstruction, open corrective osteotomy, or arthroscopic capsular release followed by takedown of the rotator cuff from the malunited proximal humerus, tuberoplasty, and then rotator cuff advancement. Although the latter technique is technically demanding, it allows preservation of the native humeral head, which is associated with a low complication rate, and avoids concerns about long-term prosthetic survival in young patients (Video).^[33]^[34]

Operative Technique

The patient was placed in a beach chair or in a lateral decubitus position. A diagnostic arthroscopy is performed with an arthroscopic pump maintaining pressure at 50 mm Hg. The joint surfaces were inspected to rule out any incongruities. The articular side of the rotator cuff is carefully assessed with a probe searching for tears. Any capsular retraction is addressed at this point. A release of the rotator interval and superior glenohumeral ligament is performed with an electrocautery introduced from an anterior portal. This was followed by a release of the posterior, inferior, and anterior capsule 5 mm away from the labrum with an electrocautery introduced from the posterior portal while the surgeon is viewing from an anterosuperolateral portal. If still present, the intra articular part of the long head of the biceps tendon undergo either tenotomy or tenodesis. After treatment of any intra-articular pathology, such as loose body removal, attention is turned to the subacromial space.
The lateral and posterolateral gutters are cleared. ny previously placed metal hardware are removed. While the surgeon is viewing from a posterior glenohumeral portal, the tuberoplasty is initiated. The arthroscope is then moved to the subacromial space, and the rotator cuff, if necessary, is sharply elevated from its malunited footprint by use of an electrocautery. Elevation of the rotator cuff consisted of the supraspinatus and anterior half of the infraspinatus, which is the part that overlies the proximally migrated tuberosity (Video).
After elevation of the rotator cuff attachments, a burr is used to perform a tuberoplasty. The cuff is assessed for mobility and integrity and is then retensioned by advancing the cuff laterally on the greater tuberosity and performing a rotator cuff repair. The rotator cuff is advanced and repaired. A modified acromioplasty with a lateral bevel is routinely performed if not done previously.

A.3 Tuberosity Insufficiency

Tuberosity insufficiency can range from contained cystic bony defects within the tuberosity to the absence of the entire tuberosity. Cystic bony defects are often encountered during primary or revision rotator cuff repair. Such defects may be idiopathic, related to a patient's rotator cuff disease, or secondary to osteolysis from breakdown of bioreabsorbable anchors. These osseous defects reduce biological healing capacity and may decrease repair fixation strength. Bone grafting techniques are needed to address these defects.^[35]

Figure. 13 Computed tomography (CT) scan show greater tuberosity bone loss.

In such a situation, a simple tendon rotator repair is usually unsuccessful, as a large bony defect significantly lowers the prognosis for primary repair.^[36]
One explanation might be that deltoid tension and therefore function is potentiated by the greater tuberosity, also called “deltoid wrapping”.^[37]
Therefore, reconstruction of this combined bony and tendon defect may require both tendinous and bony reconstruction. In older patients, such insufficiency is most reliably addressed with reverse shoulder arthroplasty. However, reverse shoulder arthroplasty is not ideal for young patients as multiple studies have demonstrated increased complications in this patient population.^[38]^[39]
Recently, a fresh frozen bony-tendinous allograft of the calcaneus and Achilles tendon has been proposed to address this difficult problem (Video). Long term results and larger series need to confirm this technique.^[40]

Surgical Technique

Allograft Reconstruction with Calcaneum and Achilles Tendon for an Irreparable Massive Rotator Cuff Tear with Bony Deficiency of the Greater Tuberosity (Video). Under general anesthesia and interscalene nerve block, the patient is placed in the beach chair position, with the operative arm draped free. An open anterosuperior incision with a deltoid split is performed in order to expose the greater tuberosity defect. The long head of the biceps was already resected. The remaining posterosuperior rotator cuff was carefully dissected and the proximal humeral head is debrided. The quality of cuff tissue is usually poor (Figure).

Figure. 14 Lateral view of a right shoulder. Observe the bony defect in the greater tuberosity associated with the poor rotator cuff tendon quality.

The Achilles tendon allograft with attached calcaneus is then prepared (Figure and Video).

Figure. 15 The allograft is prepared with an Achilles tendon.

The calcaneus is shaped to fill proximal humeral head defect. If necessary, the Achilles tendon is then split longitudinally to decrease its thickness, with the deep layer used to reinforce the rotator cuff repair. Then, the bony portion of the allograft is secured to the humeral head with a 4 mm malleolar screw under fluoroscopic control (Figure).

Figure. 16 Lateral view of a right shoulder. A malleolar screw fixes the calcaneum in the defect. The calcaneum is ready to reinforce the rotator cuff.

The native rotator cuff was then repaired onto the bony graft with a combination of an anchor and bone tunnels in the graft. The deep split of Achilles tendon is then sewn into the native posterosuperior rotator cuff to reinforce the repair (Figures and Video).

Figure. 17 Final reconstruction.

Two years follow-up confirm bony and tendinous integration (Figures).

Figure. 18 Anteroposterior X-ray of a right shoulder. The bony allograft is incorporated in the proximal humerus, filling the greater tuberosity defect.

Figure. 19 Long term computed tomography (CT) arthrogram confirming the repair of the rotator cuff.

Postoperatively, the patient wears an abduction pillow for six weeks and is allowed to perform pendulum exercises. After six weeks the abduction pillow is discontinued and passive mobilization is allowed. Full activity return and strengthening was permitted at three months, with a progressive increase of loads.

Type B: Full Thickness Tendon Lesion

B1: Lateral tendinous disruption

Full thickness disruption of the lateral tendon stump is the most frequent type of rotator cuff lesion, comprising approximately 90.1% of all surgically treated lesions (Table). Tendinous lesions most commonly involve the posterosuperior cuff. Subscapularis tears are nevertheless found in 59% of arthroscopic rotator cuff repairs.41 However, such tears are only full-thickness in 8.7% of cases, and are rarely isolated (Table).

Size of Tendon Lesion

Classifications for tear size include measurement in centimeters or number of tendons involved. This information can be derived from arthroscopy or magnetic resonance imaging and used to offer guidance on treatment and prognosis.^[41]^[42]^[43]^[44]^[45]

Once size is identified and if massive, it can be further classified according to Collin et al.^[46]

Tendon Retraction

Patte devised a method of classifying tendon coronal retraction that is often used for research purposes.^[47]

The retraction is due to tendon and muscle shortening that are not synchronous after tendon tear.^[48]

Substance loss in the later stages of musculotendinous retraction may be because of either active shortening of the tendon substance, suggesting that overreduction and lateral transposition of the tendon over the greater tuberosity may be unphysiological.

Tear Pattern

Full-thickness posterosuperior tears come in a variety of patterns. The most common categories include crescent tears, L and reverse L-shaped tears, and U-shaped tears accounting for respectively 40%, 30% and 15% of posterosuperior rotator cuff lesions.^[49]

Recognition of these tear patterns is most useful for anatomic restoration during repair. Crescent tears have good medial to lateral mobility and are amenable to a double-row repair. Longitudinal tears (L and reverse L-shaped tears, and U-shaped tears) have greater mobility in 1 plane and typically require margin convergence to achieve complete repair. Finally, massive contracted tears have also been described. These tears have limited medial to lateral and anterior to posterior mobility and typically require advanced mobilization techniques (i.e. interval slides) to achieve repair.

Releases for the Rotator Cuff

In clinical practice, rotator cuff tears may present with a wide spectrum of size and mobility. Many massive rotator cuff tears may be reparable without releases and, in contrast, some small rotator cuff tears may require releases. Release is only required if tear may not be reduced to the footprint anatomically as it would otherwise unnecessarily increase the complexity of the procedure. Releases may be divided into bursal sided releases, articular sided releases (i.e. capsular release) and interval slides.

Double-Row Versus Single-Row Cuff Repair

Biomechanical testing has consistently demonstrated the superiority of double-row constructs.^[50]

Within the domain of level I mid-term and short-term studies, double-row repair (Video) showed significant better UCLA score only (American Shoulder and Elbow Surgeons (ASES), Constant, WORC, and SANE scores showed no significance). This may correlate weakly with the significant lower partial-thickness retear rates of double-row repairs. In contrary, long-term level III studies showed a direct correlation of both functional outcomes and cuff structural integrity, with significant superiority of double-row over single-row repair techniques.^[51]

Margin Convergence

Margin convergence to bone can be used in L or V tears. This technique accomplishes margin convergence between the two leaves of the cuff, and at the same time it anchors the cuff to bone, providing very secure fixation. Margin convergence to bone has the mechanical strain reduction advantage of margin convergence coupled with strong fixation to bone. This provides a very secure component to the overall fixation construct.

Load Sharing Rip Stop Construct

Double- row repair is not possible in the setting of medially based tears, lateral tendon loss, or limited tendon mobility. Load sharing rip stop constructs demonstrated improved functional outcomes with reasonable healing rates in an otherwise challenging subset of rotator cuff tears.^[52]

This suture technique combines the advantages of a rip stop suture tape and load sharing properties of a double-row repair and has biomechanically superior properties compared to a single-row repair (Figure and Video).^[53]

Figure. 20 Anchor-based rip-stop rotator cuff repair for rotator cuff tear with lateral tendon loss. (A) A suture has been placed as an inverted mattress stitch in the rotator cuff. Two medial anchors have also been placed, and sutures from these anchors are passed medial to the rip-stop stitch. (B) Prior to tying of the sutures from the medial anchors, the rip-stop stitch is secured to bone with 2 lateral anchors. (C) Tying the suture limbs from the anchors completes the repair. Reproduce from Noyes et al., with permission.

Massive Posterosuperior Rotator Cuff Tears

Prevalence

Massive rotator cuff tears comprise approximately 20% of all cuff tears and 80% of recurrent tears.^[54]^[55]

Definition and Classification of Massive Rotator Cuff Tears

Historically a massive rotator cuff tear has been described as a tear with a diameter of 5 cm or more as described by Cofield or as a complete tear of two or more tendons as described by Gerber (Figure).^[56]^[57]

The former in particular is usually applied at the time of surgery. In an attempt to provide a preoperative MRI-based classification, Davidson et al. defined a massive tear as one with a coronal length and sagittal width greater than or equal to 2 cm.^[58]

Unfortunately, these systems are vulnerable to error due to variation in patient size and arm position at the time of measurement. It is more appropriate to define the size of a tear in terms of the amount of tendon that has been detached from the tuberosities. While the Gerber definition helps account for variability in size, there are exceptions to the complete two tendons requirement and this classification does not distinguish different patterns or predict function. Additionally, in using the term “massive”, there is a connotation of difficulty and irreparability. While challenging, most massive rotator cuff tears are reparable and other factors like the tendon retraction, atrophy, arthritis, and mobilization must be considered. Thus, in addition to the number of tendons involved, some authors proposed at least one of the two tendons must be retracted beyond the top of the humeral head (i.e Patte 3 for the supraspinatus in the coronal plane).^[59]

Such classification also takes advantage of 3-dimensional information on tear pattern, providing guidance on treatment technique.

Table: Different Classification of Massive Rotator Cuff Tears

Once a massive rotator cuff tear is identified, it can be further classified according to Collin et al.2 In this subclassification, the rotator cuff is divided into five components: supraspinatus, superior subscapularis, inferior subscapularis, infraspinatus, and teres minor (Figure).

Figure. 21 The rotator cuff is divided into 5 components: supraspinatus, superior subscapularis, inferior subscapularis, infraspinatus, and teres minor.

Rotator cuff tear patterns can then be classified into 5 types: type A, supraspinatus and superior subscapularis tears; type B, supraspinatus and entire subscapularis tears; type C, supraspinatus, superior subscapularis, and infraspinatus tears; type D, supraspinatus and infraspinatus tears; and type E, supraspinatus, infraspinatus, and teres minor tears (Figure).^[60]

Figure. 22 Rotator cuff tears classified by the involved components: type A, supraspinatus and superior subscapularis tears; type B, supraspinatus and entire subscapularis tears; type C, supraspinatus, superior subscapularis, and infraspinatus tears; type D, supraspinatus and infraspinatus tears; and type E, supraspinatus, infraspinatus, and teres minor tears.

This classification not only subclassifies massive tears but has also been linked to function, particularly the maintenance of active elevation, offering more information than the traditional six sagittal segments of Patte’s classification.

Suprascapular Nerve Neuropathy and Massive Rotator Cuff Tear

Recently there has been growing interest in the relationship between suprascapular neuropathy and massive rotator cuff tears. Theoretically, medial retraction of posterosuperior rotator cuff tears can place excessive traction on the suprascapular nerve.^[61]

However, clinical diagnosis is beset with uncertainties as the potential symptoms of suprascapular nerve neuropathy, namely, pain, weakness, and atrophy, are inseparable from those of massive rotator cuff tear. There is actually no support for routine suprascapular nerve release when repair is performed for several reasons. First, it is clearly demonstrated that repair of repair without release leads to satisfactory results. Moreover, the prevalence of suprascapular nerve neuropathy in case of massive rotator cuff tears in a prospective study is low (2%).^[62]

Treatment Options for Massive Rotator Cuffs

It should be remembered that nonoperative treatment is successful in many cases. When surgery is indicated, the primary aim is restoration of force couples and anatomic or partial repair of the rotator cuff to its footprint. However, a number of factors (refusal of the patient, biologic factors, characteristics of the tear, etc) can make these goals difficult, impossible, or unwanted to achieve. Fatty infiltration, rotator cuff retraction, and poor tendon compliance are common in patients with massive rotator cuff tears. In these situations, other approaches have been advocated, with varying degrees of success.^[63]

These include physical therapy,59,60 subacromial decompression and palliative biceps tenotomy (subacromial debridement),61 muscle transfer,62 and reverse shoulder arthroplasty.63 However, there are no randomized controlled trials comparing these various options and recommendations are mainly based on retrospective case series and the surgeon’s own experiences.^[64]^[65]^[66]^[67]^[68]

Conservative Treatment

Many patients with massive rotator cuff tears respond favorably to nonsurgical treatment. Nevertheless, patients must be aware that despite clinical improvement, future treatment may be impacted by progression of glenohumeral osteoarthritis and fatty infiltration as well as narrowing of the acromiohumeral distance. In a series of 19 patients with massive rotator cuff tears treated nonoperatively the average Constant score was 83% at a mean follow-up of 48 months. However, 50% of “reparable” tears became “irreparable” during this period.^[69]

The mainstay of nonoperative treatment includes nonsteroidal anti-inflammatory drugs, subacromial corticosteroid injections, and physical therapy. The protocol of rehabilitation focused habitually on global deltoid reconditioning and periscapular strengthening. Although certain authors proposed that re-education of the anterior deltoid muscle to compensate for a deficient rotator cuff is the cornerstone, we attach more importance to solicitation of stabilizing muscles of the glenohumeral joint with an approach based on exercises in high position. In this position, the deltoid, which acts synergistically with the remaining rotator muscles, has no upward component and participates in the articular coaptation.^[70]

In general, nonoperative management is attempted for six months before considering surgery. Younger patients (<60 years of age), however, may be immediate candidates for surgery based on the high risk for progression with conservative treatment. If after six months, symptoms have not improved, the chances of success with further nonoperative treatment decreases and operative treatment may be considered for older patients. It is unclear if it is exercise alone or exercise in combination with other interventions during the recovery process that offers the greatest benefit. In a recent prospective cohort of 45 patients suffering from pseudoparalysis with a radiographically confirmed massive rotator cuff tears, Collin and al. found after a follow-up of 48 months that the mean Constant score improved from 43 to 56 points and the mean forward flexion improved from 76 degrees to more than 160 degrees after completion of the program. They also demonstrated that effectiveness of physical therapy is related to the size and location of the lesion; if the tear involved the posterosuperior rotator cuff (B type), or only two tendons or less, most patients regained active anterior elevation that persisted for 48 months. The anterior rotator cuff is the key of anterior active elevation as only 20% of patients with MRCTs, but an intact subscapularis, develop pseudoparalysis.

Surgical (Operative) Treatment

For older patients surgery is considered when nonoperative treatment fails. Additionally, we often consider surgery as first line treatment in young patients because there is a high rate of progression with conservative treatment and for tears involving the anterior rotator cable since this area is most important to maintenance of forward elevation.

Arthroscopic Rotator Cuff Repair

The approach is to repair all of the rotator cuff that can reasonably be brought back to the tuberosities without excessive tension, and to address all potential causes of persistent pain or factors threatening the repair. The goal of a repair, even if partial, is to restore force couples and to re-establish the “suspension bridge”. In this theory, complete closure of the defect is less important than restoration of a stable fulcrum for normal shoulder kinematics. Although shoulder strength may not improve after this intervention, function is usually enhanced because of relief from pain caused by mechanical impingement. Additionally, although complete healing of massive tears is not always achievable, we believe that partial healing of the cuff may prevent secondary extension of the tear.

The Acromion and Biceps

Complete anterior acromioplasty is not advisable in the setting of a massive tear as it may lead to postoperative anterosuperior migration of the humeral head. The acromiohumeral arch is probably a component of human evolution used to compensate the deficiency of the superior rotator cuff.66 Consequently, when and how should acromioplasty should be perform is still debated.^[71]

A tenotomy or tenodesis of the long head of the biceps should be perform in the setting of a massive rotator cuff tear. There is evidence suggesting that the long head of the biceps tendon may be a source of pain and contributes to the discomfort. In a large series, Walch et al. observed an increase in the Constant score from 48.4 preoperatively to 67.6 after arthroscopic biceps tenotomy. At last follow-up, 87% of patients were satisfied or very satisfied with the result. However, the acromiohumeral interval decreased by a mean of 1.3 mm during the follow-up period.^[72]

Repair Techniques

Unfortunately, even if reinsertion of the tendon on the bone is achievable, it is often difficult to reliably achieve long-term healing with a structurally intact repair.^[73]

In the setting of a massive tear, a double-row repair improves long-term functional outcome.68-70^[74]^[75]^[76]

However, this should not be performed at the expense of over-tensioning as application of a double-row repair to a tendon with poor tendon length and excursion may lead to medial failure.^[77]

Augmentation

Graft augmentation may improve healing in massive rotator cuff tears, but add significant cost and time to the procedure.^[78]

The choice of graft is influenced by several factors including mechanical properties, host response and potential for ingrowth. Scaffolds provide mechanical support and have biological properties that may favorably influence cell proliferation and differentiation, hopefully improving tendon-to-bone healing. Currently, scaffolds derived from dermis, small intestinal submucosa, skin, fascia lata, and pericardium have been processed and marketed for augmentation in the repair of massive tears. Biological grafts are preferred, when compared to synthetic grafts, due to the unknown host response to synthetic grafts. An important factor in the longevity and strength of a graft is the amount of ingrowth.

Results of Primary Repairs

Results following arthroscopic repair of massive rotator cuffs have previously been reported.^[79]^[80]

For primary repair, improvements are observed in forward flexion (132 degrees vs 168 degrees), pain (6.3 v 1.3), UCLA score, (15.7 v 30.7) and American Shoulder and Elbow Surgeons score (41.7 v 85.7) (P<.001). A good or excellent outcome is obtained in 78% of cases. Similar results are noticed after repair of type A, B and C massive rotator cuff tears.^[81]

After revision repair, mean active forward elevation improves by 15 degrees, from 136.0 degrees ± 51.9 degrees (range, 30 to 180 degrees) at baseline to 151.4 degrees ± 41.5 degrees (range, 30 to 180 degrees) at final follow-up (P=.019). The mean pain score improves by 3.1 points, from 5.0 ± 2.4 points at baseline to 1.9 ± 2.3 points at final follow-up (p<.001). The mean American Shoulder and Elbow Surgeons (ASES) score improves from 45.7 ± 17.8 at baseline to 75.5 ± 20.3 at final follow-up (P<.001). The mean UCLA score also improves, from 16.7 ±4.9 at baseline to 26.4 ± 6.9 at final follow-up (P<.001). According to the UCLA score, functional results are excellent in 15% of cases, good in 35%, fair in 25%, and poor in 25%. Seventy-nine percent of the patients are satisfied, and 32 patients (60%) returned to their previous activities.^[82]

Revision Rotator Cuff Repair

Introduction

Failure of tendon healing after rotator cuff repair is common, reported in approximately 20% of cases depending on tear size.^[83]

Tear recurrence can be related to various factors such as: 1) inadequate strength of the initial repair construct, 2) biological failure to heal despite strong initial fixation, and 3) inappropriate post-operative rehabilitation causing structural failure of the repair.^[84]^[85]^[86]^[87]

While functional outcome has been correlated with postoperative rotator cuff integrity78 many patients maintain a satisfactory outcome despite structural failure.^[88]

The ideal treatment for a recurrent tear is thus not completely defined.

Initial Radiological Findings

The goal of imaging studies is to confirm the site of the recurrent tear. Trantalis et al. reported five patients with retearing of the cuff after double-row rotator cuff repair. All five patients had retearing medial to the medial row if sutures were placed near the musculotendinous junction of the supraspinatus.^[89]

Hayashida et al. observed that the prevalence of complete retearing of the tendon after a double-row rotator cuff repair is similar around the medial anchors with a well-preserved footprint.^[90]

Another point of interest is the quality of the tendon.^[91]

A significant and growing number of rotator cuff repairs are performed in individuals with poor rotator cuff tissue quality. Djurasovic reported an incidence of 30% (24 on 80) of poor rotator cuff tissue quality (graded subjectively at the time of surgery).^[92]

At the same time, the muscle undergoes intrinsic degeneration. After a retear, Deniz et al. found that fatty infiltration and atrophy continued to worsen significantly.^[93]

However, fatty infiltration of the supraspinatus does not seem to be a determinant factor in tendon healing. Park et al. did not find significant relationship between preoperative supraspinatus fatty infiltration and postoperative tendon healing. Contrarily, it seems that fatty infiltration of infraspinatus and subscapularis are highly significant factors (P<.001).^[94]

Another point is the bone quality. Oh et al. demonstrated that bone mineral density within the greater tuberosity decreases in patients with rotator cuff tears. In another retrospective study that investigated the relationship between greater tuberosity osteopenia and chronicity of rotator cuff tears, Cadet et al. found that there were significantly greater osteopenic changes in the greater tuberosity in patients with chronic retracted rotator cuff tears.^[95]

However, this localized osteoporosis may not influence tendon healing. In a recent study, Park et al. did not observe after primary repair that bone mineral density influenced final results.^[96]

Nevertheless, the greater tuberosity in revision cases can also be deficient due to anchor removal or perianchor cyst formation. Kim et al. observed in a retrospective case series of two hundred and nine patients bone cyst formation in 97 instances (46.4%), and these authors questioned the utility of bioabsorbable anchors because of possible interference with revision surgery. Consequent bone lysis can be noticed after trauma. Lädermann et al. reported massive bone resorption after osteosynthesis of the greater tuberosity leading to combined tendon and bony insufficiency and pseudoparalysis/pseudoparesis.

When milestones of typical post-operative recovery are not met, analysis of rotator cuff repair should be considered and a multi-modal evaluation is required. The goal of imaging studies is to confirm the site of the recurrent tear (Figure)86,92 the type of failure (e.g. in continuity), and if possible, it’s cause.^[97]^[98]^[99] File:Sensitive-content.pngal, or perianchor cyst formation and (F) bony and tendinous insufficiency. Reproduced from Lädermann et al., with permission. Other points of interest are the quality of the bone (tuberosity deficiency), tendon, and muscle, and whether further surgery is feasible.^[100]^[101]

Standard shoulder radiographs, including anteroposterior, axillary lateral and scapular Y (outlet) views, may demonstrate decreased acromiohumeral distance, glenohumeral arthritis, subacromial spurs, acetabularization of the acromion, femoralization of the humeral head, and implant or anchor migration.^[102]^[103]

It can also be used to rule out chondrolysis, anchor migration or prominence, and acromial fracture. Among evaluation techniques, the most widely accepted reference standard is magnetic resonance imaging which allows visualization of the tendons and does not involve radiation exposure. Intra-articular contrast may be used in association with magnetic resonance imaging to increase the sensitivity for detecting a recurrent tear.^[104]

Postoperative magnetic resonance imaging images are difficult to interpret; inadequate coverage of the greater or lesser tuberosity may indicate partial healing and not a recurrent full-thickness tear.^[105]^[106]^[107]

Furthermore, only 10% of re-attached tendons generate a normal magnetic resonance imaging signal. Thus, a common finding is the presence of an intermediate signal within the tendon indicating granulation tissue or of a low-intensity signal produced by fibrous tissue.^[108]^[109]

These signal changes may persist for longer than six months, due to tissue remodeling, and seem to have no clinical implications.^[110]^[111]

Finally, the evaluation of magnetic resonance imaging scans is made difficult by the normal leakage of fluid into the subacromial space after the opening of the rotator interval and passage of instruments through the tendon, which may contain artifacts generated, for instance, by metal anchors or high-strength sutures. These factors, together with the high cost of magnetic resonance imaging, lend considerable appeal to ultrasound as a method for evaluating rotator cuff repair, even if its effectiveness is operator-dependent.^[112]

Computed tomography arthrogram can also be used to aid in the identification of recurrent rotator cuff tears when neither ultrasound or magnetic resonance imaging are options.^[113]

Failure after rotator cuff repair was previously believed to occur during the first three months.^[114]^[115]

While the majority of retears do occur within the first three months, it has now been demonstrated retears can occur up to six months after repair.^[116]^[117]^[118]

Recent prospective studies have confirmed that ultrasound has a high sensitivity and specificity for detecting a recurrent rotator cuff tear compared to magnetic resonance imaging.In a study comparing magnetic resonance imaging and ultrasound after rotator cuff repair, Codsi et al. found 92% agreement with a coefficient of 0.70.^[119]

Similarly, Collin et al. reported that ultrasound had 80% sensitivity and 98% specificity compared to magnetic resonance imaging.^[120]

Treatment

Non Surgical (Conservative) Treatment of Failed Rotator Cuff Repair

Jost et al. evaluated 20 patients with a failed rotator cuff repair at a mean follow-up of 38 months and reported that the adjusted Constant score and shoulder simple value averaged 83% and 75%, respectively.^[121]

Namdari et al. demonstrated a successful outcome in 54% of patients (defined by an American Shoulder and Elbow Surgeons score of more than 80 points) and a mean 15 point improvement in the American Shoulder and Elbow Surgeons score at a mean of 52 months postoperative. Finally, the same group compared the two and ten year results for patients with known structural failures of rotator cuff repair. The average long-term American Shoulder and Elbow Surgeons score was 79 points (range, 50 to 95 points) and the average visual analog scale pain score was 2.2 points (range, 1 to 4 points); both scores were unchanged from those at two years. The average simple shoulder test score was 9.2 points (range, 6 to 12 points), and the average age-adjusted Constant score was 73 points (range, 59 to 90 points).^[122]

Surgical (Operative) Treatment Revision Rotator Cuff Repair

Surgical Technique

The alarming retear rate indicates that several surgical options can be considered which must be individualized to the patient. For example, in the setting of an acute traumatic retear in a physiologically young, healthy, active and non-pseudoparalytic patient, arthroscopic revision surgery is generally recommended. Techniques to enhance mechanical fixation, such as linked load-sharing rip-stop constructs should be considered.^[123]

Augmented repair using scaffold devices derived from autografts,46,119,120 allograft,121 xenograft extracellular matrix122 or synthetic matrices such as poly-l-lactide grafts123 have been used to offer a structural support of the repair during the crucial healing period and to improve healing rates. The scientific literature does not contain enough data to justify any systematic associated augmentation techniques. Tendon transfers may be used in patients without advanced glenohumeral arthritis who have significant loss of external rotation strength and maintain anterior active elevation.62,124 If the patient is young, pseudoparalytic and suffers from a combined bony and tendinous rotator cuff insufficiency, calcaneum and Achilles tendon allograft could be considered.40

Finally, whereas primary pseudoparalysis responds well to arthroscopic rotator cuff repair, persistent pseudoparalysis after a previous attempt at rotator cuff repair may be more predictably managed with reverse shoulder arthroplasty. Denard et al. reported that pseudoparalysis/pseudoparesis was reversed in the revision setting in only 43% of patients with a low rate (54%) of satisfaction.^[124]

In contrast, Boileau et al. found that anterior elevation was reliably restored with reverse shoulder arthroplasty after failed rotator cuff repair and 73% of patients were satisfied.^[125]

Clinical and Radiological Results After Revision Rotator Cuff Repair

The clinical results of are summarized in the Table. Overall, range of motion improved, except in one series of open rotator cuff repair.94 Functional outcome improved in all series and 70% or more of patients were satisfied or very satisfied.^[126]

Table: Clinical Results of Revision RCR

Complication

The short- to intermediate-term incidence of complications, including subsequent revision surgery, after revision rotator cuff repair is relatively low, around ten percent in this review (Table). However, most studies primarily considered reoperation a complication and did not examine complications such as hematoma, hardware failure, and postoperative stiffness. The prevalence of postoperative complications is therefore probably higher than reported. The prevalence of non-healing or retear was around 40% (range, 0 to 62%) in the four studies with postoperative imaging.^[127]^[128]^[129]^[130]

Furthermore, these tears may progress with time; Shamsudin et al. reported a prevalence of defect of 28% at six months and of 40% at two years. If revision is planned, patients have to be aware of the high prevalence of persistent structural defect. Moreover, retear rate after reoperation continues to deteriorate with time.^[131]^[132]

Structural failure does not always result in clinical failure. Many patients with partial healing of the cuff and a residual defect will be much improved after surgery. Characteristics associated with successful and unsuccessful results after structural failure of rotator cuff repair are poorly understood. Retear or non-healing of tendons is rather frequent and surgery is rarely proposed because this condition is often well tolerated with marked clinical improvement in comparison with the preoperative state.^[133]

One reason for clinical failure is probably the non-restoration of balanced force couples and the suspension bridge system of force transmission in the shoulder. The location (involvement of the subscapularis on which the rotator cable is attached) and the size (more than two tendons) are the primary determinant of rotator cuff function.

Risk Factors for Postoperative Poorer Results

Several patient-related factors appear to be associated with poorer results. The most important factor seems to be poor preoperative range of motion. Female sex and, in one study, if the surgery was performed on the dominant arm, were negatively associated with postoperative outcome.^[134]^[135]^[136]

There is still controversy about certain risk factors such as age of patients. Disease-related factors included patients with a recurrent tear after the revision repair, preoperative visual analogue scale pain score greater than five, and poor preoperative range of motion. The range vary from less than 90 degrees in the studies from Denard et al. and Piasecki et al. to 140 degrees in the study of Chuang et al.^[137]^[138]^[139]

The latter factor has been reported in almost all series and is probably the most important preoperative indicator. In addition, acromiohumeral distance (less than seven mm) can be associated with a satisfactory outcome.^[140]

There is controversy about patients with more than one prior surgery, with one study reporting that this negatively impacted results and another study reporting that it did not.^[141]^[142]

Operative-related factors like poor tendon quality54,88 is associated with poorer results.^[143]^[144]

One study compared outcomes between massive and non-massive tears and did not find any significant difference in terms of post-operative anterior elevation, pain, or functional outcome.^[145]

Post-revision Rehabilitation

In all studies, subjects took part in standardized rehabilitation protocols. Most studies did not allow immediate overhead passive motion. Most studies recommend sling during 6 weeks. Strengthening is delayed until six to sixteen weeks post-operatively. Full return to activity was not allowed until four to twelve months.

B2: Medial Tendinous Disruption

Disruption of the tendon medial to an intact lateral tendon stump has been reported in primary chronic and acute cases or postoperatively as a failure medial to the medial row.^[146]^[147]

Regarding the former, it is now understood that the infraspinatus insertion is quite broad and wraps around from posterior to anterior to occupy much of the lateral greater tuberosity. Therefore, such descriptions of a lateral tendon stump remaining may, in fact, represent a torn supraspinatus with an intact infraspinatus.

Full thickness defects medial to an intact footprint of the rotator cuff can be seen following a rotator cuff repair (Figure). Trantalis et al. described 5 patients with medial failure following a double-row rotator cuff repair. Such failure results from overtensioning during repair and is very difficult to manage with revision repair. These lesions do not produce muscular edema, except in traumatic cases with important and acute retraction of the muscle and the remnant of the tendon (Figure); its origin is then either retraction (which may appear in some hours) or neurological lesions (noted after some weeks).^[148]

B3: Tendon to Tendon Adhesion: “Fosbury Flop Tear”

The Fosbury flop tear occurs from a full thickness tear that has flipped upon itself and adhered medially (Figure).^[149]

Figure. 25 Figure: Illustration of a “Fosbury flop tear” development. Reproduced from Lädermann et al., with permission.

Prevalence

In a prospective study spanning one-year, Lädermann et al. reported five patients with full or partial-thickness rotator cuff lesions in a series of 97 (5 % incidence rate).142 Radiologically, these lesions showed a thicker than normal tendon stump on the bursal-side of the retracted supraspinatus tendon in a superomedial orientation.^[150]

Figure. 26 Coronal T1 weighted image of a right shoulder that demonstrates (black arrow) an abnormally thickened supraspinatus (9.5 mm). Reproduced from Lädermann et al., with permission.

Figure. 27 Coronal T1 weighted MRA image with fat saturation of a right shoulder demonstrates adhesions between the bursal side of the tendon and the wall of the subacromial bursa (red arrow), and abnormal orientation of the fibers stump (yellow arrow). Reproduced from Lädermann et al., with permission.

Additionally, patients with this lesion were also found to have an accumulation of fluid in the superomedial part of the subacromial bursa as well as adhesions between the wall of the subacromial bursa and the tendon of the supraspinatus. Since the original description, another group verified the same entity.

151. Nakamizo H. Arthroscopic repair for subacromial incarceration of a torn rotator cuff. AP-SMART 2015;2:90-4.