Arthroscopic rotator interval repair: the three-step all-inside technique

Controversies in surgical management of anterior shoulder instability. State of the Art

Arthroscopic Bankart repair (ABR) has been accepted as a standard procedure for anterior shoulder instability with a minimum or no glenoid bone loss and an on-track Hill-Sachs lesion if present. However, several controversies exist in the surgical treatment of anterior shoulder instability. This article will discuss some of these controversies in, "simple," dislocations (without bone loss) as well as, "complex," (with critical bone loss). Determining which patients will benefit from an arthroscopic procedure depends on multiple factors including age, activity level, adequate determination of bone loss, performed with feasible and reliable imaging techniques. In the absence of concomitant significant bony and soft tissue pathology, ABR alone can provide satisfactory clinical results on a long-term basis. Controversies, including whether to remove cartilage from the edge of the glenoid, knotted versus knotless anchors, and routine rotator interval closure, still exist. In cases with significant bone loss, several bone restoring procedures have been described, such as, the Latarjet procedure, iliac crest bone graft, arthroscopic anatomic glenoid reconstruction with a frozen distal tibial allograft, and fresh distal tibial allograft reconstruction. This article will address these controversies and provide guidance based on available published data.

The Angular Relationships Between the Coracohumeral Ligament and Adjacent Shoulder Structures Are Variable

Purpose

To describe the arthroscopic anatomy of the coracohumeral ligament (CHL) in relation to visible anatomic reference points to aid in the execution of a more effective arthroscopic medial-lateral rotator interval closure.

Methods

Detailed dissection to identify the CHL was performed in 4 shoulders from 2 fresh-frozen donor cadavers with a deltopectoral approach. The angular relationship between the CHL and the superior border of the subscapularis tendon was determined via gross dissection. Arthroscopic images were used to determine the angular position of the CHL in relation to both the glenoid articular surface and the intraarticular segment of the tendon of the long head of the biceps brachii (LHB).

Results

Analysis of 4 cadaveric shoulders via gross dissection demonstrated the CHL to subtend a mean angle of 29° (range 16° to 39°) with respect to the superior border of the subscapularis tendon. Arthroscopic analysis of 4 cadaveric shoulders demonstrated the CHL to subtend a mean angle of 59° (range 38° to 77°) with respect to the glenoid articular surface. Additionally, arthroscopic analysis of 2 cadaveric shoulders demonstrated the CHL to subtend a mean angle of 29° (range 11° to 47°) with respect to the LHB tendon.

Conclusion

Although the position of the CHL in relation to the subscapularis tendon, glenoid articular surface, and LHB tendon demonstrates a moderate degree of anatomic variability, these structures provide valuable anatomic reference points for the identification of the course of this significant static shoulder stabilizer.

Clinical Relevance

Comprehensive understanding of the angular relationships between the CHL and adjacent shoulder structures may assist with the execution of a more effective arthroscopic rotator interval closure.

Outcomes After Arthroscopic Rotator Interval Closure for Shoulder Instability: A Systematic Review

PURPOSE

(1) To systematically assess the clinical outcomes of arthroscopic rotator interval closure (RIC) procedures for shoulder instability and (2) to report the different technical descriptions and surgical indications for this procedure.

METHODS

Two independent reviewers searched 4 databases (PubMed, Embase, Web of Science, and Cochrane) from database inception until October 15, 2017. The inclusion criteria were studies that reported outcomes of shoulder stabilization using arthroscopic RIC as an isolated or adjunctive surgical procedure. The methodologic quality of studies was assessed with the Methodological Index for Non-Randomized Studies tool and Grading of Recommendations Assessment, Development and Evaluation system for randomized controlled trials.

RESULTS

Fifteen studies met our search criteria (524 patients). Of the studies, 12 were graded Level IV evidence; 2, Level III; and 1, Level II. Six different RIC technique descriptions were reported, with 2 studies not defining the details of the procedure. The most common method of RIC was arthroscopic plication of the superior glenohumeral ligament to the middle glenohumeral ligament (8 of 15 studies). The most commonly used patient-reported outcome measure was the Rowe score, with all studies reporting a minimum postoperative score of 80 points. The rate of return to preinjury level of sport ranged from 22% to 100%, and the postoperative redislocation rate ranged from 0% to 16%.

CONCLUSIONS

The indications for RIC were poorly reported, and the surgical techniques were inconsistent. Although most studies reported positive clinical results, the heterogeneity of outcome measures limited our ability to make definitive statements about which types of rotator interval capsular closure are warranted for select subgroups undergoing arthroscopic shoulder stabilization.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II through IV studies.

The Rotator Interval of the Shoulder: Implications in the Treatment of Shoulder Instability

Biomechanical studies have shown that repair or plication of rotator interval (RI) ligamentous and capsular structures decreases glenohumeral joint laxity in various directions. Clinical outcomes studies have reported successful outcomes after repair or plication of these structures in patients undergoing shoulder stabilization procedures. Recent studies describing arthroscopic techniques to address these structures have intensified the debate over the potential benefit of these procedures as well as highlighted the differences between open and arthroscopic RI procedures. The purposes of this study were to review the structures of the RI and their contribution to shoulder instability, to discuss the biomechanical and clinical effects of repair or plication of rotator interval structures, and to describe the various surgical techniques used for these procedures and outcomes.

Outcome of Bankart repair in contact versus non-contact athletes

BACKGROUND

The clinical results of arthroscopic Bankart repair for contact athletes varies according to published reports. The purposes of this study were to analyze the clinical outcome of open or arthroscopic Bankart repair and to investigate the results in contact and non-contact athletes.

HYPOTHESIS

Clinical outcome of arthroscopic Bankart repair is similar to that of open procedure.

PATIENTS AND METHODS

One hundred patients with recurrent anterior shoulder dislocation without a large bony defect were retrospectively reviewed. Fifty-one contact and 49 non-contact athletes were found with a mean follow-up of 17 months. Forty-nine shoulders underwent arthroscopic Bankart repairs; 51 shoulders had open Bankart repairs.

RESULTS

In non-contact athletes, there was a 5% (1/22 cases) recurrence rate in the open group and 4% (1/27 cases) in the arthroscopic group. In contrast, in contact athletes, there was a 10% (3/29 cases) recurrence rate in the open group and 14% (3/22 cases) in the arthroscopic group. There was no significant difference in the recurrence rate between contact and non-contact athletes, although contact athletes showed two to three times a higher recurrence rate than that of non-contact athletes. The Rowe score and Constant score showed no significant difference between the two procedures and between the contact and non-contact athletes. The rate of the complete return to sports showed no significant difference between contact and non-contact athletes.

CONCLUSION

The recurrence rate of Bankart repair in the contact athletes was 2 times higher in the open group and 3 times higher in the arthroscopic group than in the non-contact athletes. Clinical outcome of arthroscopic Bankart repair was similar to that of open procedure.

Arthroscopic rotator interval closure by purse string suture for symptomatic inferior shoulder instability

Multidirectional instability of the shoulder is a complex condition that can be difficult to diagnose and treat. Clinically, it is characterized by symptomatic global laxity of the glenohumeral joint and may present either traumatically or atraumatically, unilaterally or bilaterally, and with or without generalized joint laxity. Capsular plication is a primary treatment option in these patients and is used to tension the redundant or lax capsule. We evaluated the role of rotator interval closure in restoring stability as a primary procedure in patients with multidirectional instability and a positive and painful sulcus sign.Twenty adult patients (16 men and 4 women) presenting with multidirectional instability were evaluated clinically and radiologically to assess the degree and direction of instability, were treated by arthroscopic rotator interval closure and inferior capsular plication, and were followed up for a minimum of 2 years. Clinical and functional results were excellent at 2-year follow-up. The results of the study indicate that the closure of the rotator interval in patients with symptomatic inferior instability will have a long-lasting effect on the stability and function of the shoulder, as the closure improves not only the static restraints but also the dynamic restraints of the shoulder through the improved proprioception secondary to restoration of the rotator interval structures.

Arthroscopic rotator interval closure in shoulder instability repair: a retrospective study

BACKGROUND

Arthroscopic Bankart repair (ABR) is a standard treatment for recurrent anterior shoulder instability. Young age, hyperlaxity, loss of bone stock and multidirectional or voluntary type of instability are all associated with failure of this procedure. Rotator interval laxity is associated with shoulder instability, whereas rotator interval closure increases humeral head stability and reduces shoulder range of motion.

METHODS

The records of patients with recurrent anterior shoulder dislocations who underwent ABR with or without arthroscopic rotator interval closure (ARIC) in our department between 1999 and 2007 were reviewed. Rates of recurrent dislocation or symptomatic subluxation as well as functional outcome were evaluated using Walch-Dupley score.

RESULTS

Three (8.1%) of the 37 ABR+ARIC patients (age 19-44 years, 32 males) had re-dislocated their shoulder at 42±16 months following the procedure, all of which had systemic joint hyperlaxity. Six (13%) of the 46 ABR patients (age 19-39 years, 42 males) had re-dislocated their shoulder at 13±14 months, three of which had systemic joint hyperlaxity and dislocated their shoulder within 1 year following the operation. Systemic joint hyperlaxity (28% of ABR and 41% of ABR+ARIC patients) was significantly associated with recurrent dislocation and poor functional outcome. ABR+ARIC patients had slightly more limited range of motion with similar good and excellent functional results (75%) at final follow up time.

CONCLUSIONS

Systemic joint hyperlaxity is a risk factor for failure of ABR. When ARIC is performed in combination with ABR, it may have an additive effect on shoulder stability.

Biomechanical analysis comparing a traditional superior-inferior arthroscopic rotator interval closure with a novel medial-lateral technique in a cadaveric multidirectional instability model

BACKGROUND

Commonly performed arthroscopic rotator interval closure techniques that imbricate the rotator interval in a superior-inferior direction have been unable to reproduce the stabilizing effects of an open medial-lateral rotator interval imbrication.

HYPOTHESIS

The medial-lateral rotator interval closure will allow less inferior and posterior glenohumeral translation than the superior-inferior rotator interval closure, and the medial-lateral rotator interval closure will result in less loss of external rotation than the superior-inferior closure.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight match-paired cadaveric shoulders were stretched to 10% beyond the maximum range of motion in 0 degrees and 60 degrees of glenohumeral abduction to create a multidirectional instability model. Shoulders were then repaired using a superior-inferior rotator interval closure or an arthroscopic medial-lateral rotator interval closure with an anchor in the humeral head. Rotational range of motion, glenohumeral translation, and humeral head apex position were measured for intact, stretched, and repaired conditions in both 0 degrees and 60 degrees of glenohumeral abduction.

RESULTS

In 0 degrees of abduction, after both rotator interval closure techniques, external rotation decreased significantly (by 4.4%; P < .05) relative to the stretched state and was restored to the intact state. In 60 degrees of abduction, only the medial-lateral rotator interval closure restored range of motion to the intact state. In 60 degrees of abduction, the medial-lateral rotator interval closure was more effective in reducing posterior translation than was the superior-inferior closure (P = .03).

CONCLUSION

The medial-lateral rotator interval closure restored range of motion to the intact state better than the superior-inferior closure. Compared with the superior-inferior rotator interval closure, the medial-lateral closure significantly decreased posterior translation with the shoulder in abduction and external rotation.

CLINICAL RELEVANCE

Arthroscopic medial-lateral rotator interval closure with a suture anchor in the humeral head can be considered in the surgical treatment of patients with multidirectional instability, especially those with a component of posterior instability, without concern for excessive loss of range of motion.

An analysis of the rotator interval in patients with anterior, posterior, and multidirectional shoulder instability

PURPOSE

To describe anatomic measurements of the rotator interval (RI) on magnetic resonance arthrogram (MRA) images and to assess the relationship between increased dimensions of the RI and instability conditions of the shoulder.

METHODS

Three groups of patients with clinical instability were treated arthroscopically (anterior [A = 19 patients], posterior [P = 14 patients], and multidirectional [M = 13 patients]), and a group of 10 control patients without clinical instability were also identified. The MRAs of all groups were randomized, and 5 blinded reviewers recorded RI anatomic measurements of: (1) sagittal measures of the distance between the subscapularis (SSc) and supraspinatus (SS) tendons at 3 anatomic landmarks across the RI, and (2) the sagittal position of the long head of the biceps (LHB) relative to the most anterior aspect of the SS.

RESULTS

The rotator interval distance between the SS and SSc tendons was nearly identical for all groups of instability, and was also not different from control groups. On the sagittal oblique sequences, the distance from the LHB tendon to the anterior edge of the SS tendon was significantly increased in posterior (7.4 mm) instability versus both the control group (2.4 mm; P = .025) and those with anterior instability (4.5 mm; P = .041), with the LHB in a consistent anterior position. The remainder of the measures was not statistically different between the groups.

CONCLUSIONS

The distance between the SS and SSc and the overall size of the RI was well preserved in all instability patterns and control conditions. The LHB tendon assumes a more anterior position relative to the supraspinatus tendon in patients with posterior instability versus those patients with anterior instability or those without clinical instability. Additional work is necessary to further define objective radiographic evidence of RI insufficiency in patients with shoulder instability.

LEVEL OF EVIDENCE

Level III, prognostic case-control study.

The addition of rotator interval closure after arthroscopic repair of either anterior or posterior shoulder instability: effect on glenohumeral translation and range of motion

BACKGROUND

Although the use of rotator interval closure is frequently advocated as a useful supplement to shoulder instability repairs, the addition of a rotator interval closure after arthroscopic instability repair has not been fully investigated.

PURPOSE

The objective of this study was to investigate whether a rotator interval closure improves glenohumeral stability in an anterior and posterior instability shoulder model.

STUDY DESIGN

Controlled laboratory study.

METHODS

Fourteen fresh-frozen cadaveric shoulder specimens were dissected free of soft tissues, leaving the rotator cuff intact with simulated cuff loading. All specimens were mounted in a custom testing apparatus using infrared sensors to document glenohumeral translation and rotation. The specimens were then tested for stability in the following order: vented/subluxated state, after arthroscopic anterior (Group 1; 7 specimens) or posterior (Group 2; 7 specimens) instability repair with suture anchors, and then after rotator interval closure. For each of the 3 testing conditions, the following were measured: (1) external and internal rotation at neutral, (2) external and internal rotation at 90 degrees of abduction, (3) posterior and anterior translation at neutral rotation (15 N and 25 N), (4) anterior translation at 90 degrees of abduction and external rotation (Group 1; 15 N and 25 N), (5) posterior translation at 90 degrees of flexion and internal rotation (Group 2; 15 N and 25 N), and (6) sulcus testing in neutral (7.5 N).

RESULTS

Posterior stability was only improved after anchor capsulolabral repair (8.0 to 5.0 mm; P = .017, 25 N), but there was no improvement after rotator interval closure (5.0 to 4.6 mm; P = .453). However, anterior stability was improved after capsulolabral repair (8.6 to 4.0 mm; P = .016, 25 N) and also improved further by rotator interval closure (4.0 to 2.4 mm; P = .007). The mean loss of external rotation was significantly increased by the addition of the rotator interval closure in both neutral and abducted glenohumeral positions, with a mean external rotation loss of 28 degrees in neutral (P = .013). The addition of a rotator interval closure did not improve sulcus stability (P = .4).

CONCLUSION

The addition of an arthroscopic rotator interval closure after posterior capsulolabral repair did not improve posterior stability; however, anterior stability was improved further after a rotator interval closure. Inferior stability was not improved. Arthroscopic rotator interval closure significantly decreased external rotation at both neutral and abducted arm positions.

CLINICAL RELEVANCE

Arthroscopic closure may be beneficial in certain cases of anterior shoulder instability; however, posterior instability was not improved. Predictable losses of external rotation after rotator interval closure are of concern.

Rotator interval dimensions in different shoulder arthroscopy positions: a cadaveric study

The rotator interval was defined as a triangular structure, where the base of the triangle was the coracoid base, the upper border was the anterior margin of the supraspinatus, and the lower border was the superior margin of the subscapularis muscle-tendon unit. We evaluated the rotator interval dimensions in 15 shoulders from 10 lightly embalmed adult cadavers in 3 shoulder arthroscopy positions: 0 degrees of abduction and 30 degrees of flexion (beach chair [BC]), 45 degrees of abduction and 30 degrees of flexion (lateral decubitus 1), and 70 degrees of abduction and 30 degrees of flexion (lateral decubitus 2). In each shoulder position, measurements were made in neutral rotation (NR), 45 degrees of external rotation (ER), and 45 degrees of internal rotation (IR). The coracoid base lengthened with IR in all positions and shortened in ER in the lateral decubitus position but not in the BC position. Abduction significantly lengthened the coracoid base, which was shortest in the BC position with ER (24 +/- 4 mm) and longest in the lateral decubitus 2 position with IR (33 +/- 5 mm). The coracoid base, where sutures are placed during plication of the interval, was observed to lengthen and, therefore, loosen with IR and abduction. To prevent postoperative ER restriction, plication should be made in ER or neutral rotation when operating in the BC position and the degree of abduction should be decreased and the shoulder held in ER when operating in the lateral decubitus position.

Arthroscopic versus open rotator interval closure: biomechanical evaluation of stability and motion

PURPOSE

The purposes of this study were to investigate the differences between open and arthroscopic closure of the rotator interval (RI) on glenohumeral translation and range of motion. We also sought to determine if the addition of either an open or arthroscopic RI closure increases stability of the shoulder.

METHODS

Fourteen fresh-frozen (10 paired) cadaveric shoulder specimens were mounted in a custom testing apparatus, and glenohumeral translation and rotation were obtained by using an optoelectric tracking system (Optotrak Certus; Northern Digital, Ontario, Canada). Specimens were randomly allocated to either open (n = 7) or arthroscopic (n = 7) plication of the RI. The following were measured first with an intact and vented specimen and subsequently after an RI closure using either open or arthroscopic techniques: (1) range of motion in neutral and 90 degrees abduction; (2) anterior and posterior translation at neutral rotation; (3) anterior translation at 90 degrees abduction with external rotation; and (4) posterior translation at 90 degrees flexion with internal rotation.

RESULTS

Posterior stability was not improved from the intact state by either open (1.0-mm change) or arthroscopic (0.1-mm change) repair. The sulcus stability was improved in the open group (5.7 mm to 2.9 mm, P = .028), but not arthroscopically (5.1 to 4.1 mm, P = .499). Neutral anterior stability was improved after open repair (7.2 to 2.6 mm, P = .018), but not arthroscopically (2.3 to 2.4 mm, P = 0.5). However, anterior stability in external rotation (ER) at 90 degrees abduction was improved in the arthroscopic repair group (5.5 to 3.1 mm, P = .006). The mean loss of ER in neutral was greater in the open group (40.8 degrees) versus the arthroscopic group (24.4 degrees, P = .0038). The arthroscopic group showed an 11.7 degrees loss of ER in 90 degree abduction (P = .018) versus the open group loss of 4.8 degrees. There were no significant differences in loss of IR in either neutral or 90 degree abduction.

CONCLUSIONS

Posterior stability was not improved by either open or arthroscopic rotator interval repair, and sulcus stability only improved with the open technique. Anterior stability in neutral was improved after open repair and in the arthroscopic repair group with the arm abducted. There was a large loss of external rotation with both techniques.

CLINICAL RELEVANCE

This study suggests that arthroscopic RI closure adds little to the overall posterior and inferior stability of the shoulder joint, although anterior stability may be improved. There is a potentially large loss of external rotation after either repair method.

The rotator interval: anatomy, pathology, and strategies for treatment

Over the past two decades, it has become accepted that the rotator interval is a distinct anatomic entity that plays an important role in affecting the proper function of the glenohumeral joint. The rotator interval is an anatomic region in the anterosuperior aspect of the glenohumeral joint that represents a complex interaction of the fibers of the coracohumeral ligament, the superior glenohumeral ligament, the glenohumeral joint capsule, and the supraspinatus and subscapularis tendons. As basic science and clinical studies continue to elucidate the precise role of the rotator interval, understanding of and therapeutic interventions for rotator interval pathology also continue to evolve. Lesions of the rotator interval may result in glenohumeral joint contractures, shoulder instability, or in lesions to the long head of the biceps tendon. Long-term clinical trials may clarify the results of current surgical interventions and further enhance understanding of the rotator interval.

Effect of rotator interval closure on glenohumeral stability and motion: a cadaveric study

The effect of rotator interval closure, which is performed as an adjunct to arthroscopic stabilization of the shoulder, has not been clarified. Fourteen fresh-frozen cadaveric shoulders were used. The position of the humeral head was measured using an electromagnetic tracking device with the capsule intact, sectioned, and imbricated between the superior glenohumeral ligament and the subscapularis tendon (SGHL/SSC closure) or between the superior and middle glenohumeral ligaments (SGHL/MGHL closure). The direction of translational loads (10, 20, and 30 N) and arm positions were (1) anterior, posterior, and inferior loads in adduction; (2) anterior load in abduction/external rotation in the scapular plane; and (3) anterior load in abduction/external rotation in the coronal plane. The range of motion was measured using a goniometer under a constant force. Both methods reduced anterior translation in adduction. Only SGHL/MGHL closure reduced anterior translation in abduction/external rotation in the scapular plane and posterior translation in adduction. Both methods reduced the range of external rotation and horizontal abduction. Rotator interval closure is expected to reduce remnant anterior/posterior instability and thereby improve the clinical outcomes of arthroscopic stabilization procedures.