Background: The advantage of single-row versus double-row arthroscopic rotator cuff repair techniques has been a controversial issue in sports medicine and shoulder surgery. There is biomechanical evidence that double-row techniques are superior to single-row techniques; however, there is no clinical evidence that the double-row technique provides an improved functional outcome.
Hypothesis: When compared with single-row rotator cuff repair, double-row fixation, although biomechanically superior, has no clinical benefit with respect to retear rate or improved functional outcome.
Study Design: Systematic review.
Methods: The authors reviewed prospective studies of level I or II clinical evidence that compared the efficacy of single- and double-row rotator cuff repairs. Functional outcome scores included the American Shoulder and Elbow Surgeons (ASES) shoulder scale, the Constant shoulder score, and the University of California, Los Angeles (UCLA) shoulder rating scale. Radiographic failures and complications were also analyzed. A test of heterogeneity for patient demographics was also performed to determine if there were differences in the patient profiles across the included studies.
Results: Seven studies fulfilled our inclusion criteria. The test of heterogeneity across these studies showed no differences. The functional ASES, Constant, and UCLA outcome scores revealed no difference between single- and double-row rotator cuff repairs. The total retear rate, which included both complete and partial retears, was 43.1% for the single-row repair and 27.2% for the double-row repair (P = .057), representing a trend toward higher failures in the single-row group.
Conclusion: Through a comprehensive literature search and meta-analysis of current arthroscopic rotator cuff repairs, we found that the single-row repairs did not differ from the double-row repairs in functional outcome scores. The double-row repairs revealed a trend toward a lower radiographic proven retear rate, although the data did not reach statistical significance. There may be a concerning trend toward higher retear rates in patients undergoing a single-row repair, but further studies are required.
Background: Complete repair of massive rotator cuff tears can be limited by tendon retraction and poor tissue quality. When a complete repair cannot be accomplished, a significant partial repair may be possible.
Hypothesis: A partial repair will yield comparable outcomes to complete repair of massive rotator cuff tears in this specific patient population.
Study Design: Cohort study; Level of evidence, 3.
Methods: All consecutive arthroscopic rotator cuff repairs done at the authors’ institution over a 2-year period were identified. A retrospective chart review was performed. Inclusion criteria required that each patient have a massive rotator cuff tear (30 cm2 or greater). Patients were categorized as either partial or complete repair. The University of California, Los Angeles (UCLA) shoulder scores were used to measure patient outcomes at an average follow-up of 24 months (10-40 months).
Results: Of 1128 consecutive arthroscopic rotator cuff repairs, 97 (9%) patients were noted intraoperatively to have massive tears measuring 30 cm2 or greater. Complete repair was achieved in 52 patients, whereas partial repair was possible in 45 patients. Eleven patients were lost to follow-up. The 41 remaining patients with only partial repair achieved a postoperative mean UCLA score of 29.49, and the 45 patients with complete repair achieved a mean UCLA score of 29.64, yielding significant improvement in both the partial repair group (P = .0001) and the complete repair group (P = .0001) compared with preoperative UCLA scores. However, no statistically significant differences in postoperative outcomes were noted when the 2 groups were compared with one another (P = .89).
Conclusion: Partial repair of massive rotator cuff tears yielded outcomes comparable with complete repair of massive tears.
Background: There is no consensus as to the amount and direction of capsular plication necessary to correct anterior shoulder instability without overconstraining the joint.
Hypothesis: An arthroscopic capsulorrhaphy in line with the fibers of the inferior glenohumeral ligament (IGHL) in an anterior laxity model will restore glenohumeral kinematics to normal.
Study Design: Controlled laboratory study.
Methods: Six cadaveric specimens were tested in both the scapular and coronal plane in 3 conditions: intact, anterior instability, and plicated. The anterior instability model was created by stretching the shoulder 20% beyond the physiological external rotational range of motion, and plication was achieved by performing a 10-mm arthroscopic plication in line with the fibers of the anterior band of the IGHL.
Results: Stretching significantly increased the rotational range of motion, while plication restored it back to that of the intact condition (P < .05). There were few significant changes in humeral head apex position across all 3 testing conditions. Plication significantly reduced anterior translation compared with the stretched condition (P < .05). Stretching and plication both significantly reduced contact area relative to the intact condition (P < .05). There were no significant differences between any of the 3 conditions for contact pressure and only few significant differences between the conditions for contact peak pressure.
Conclusion: A 10-mm capsular plication in line with the fibers of the anterior band of the IGHL effectively reduces capsular laxity without overconstraining the joint.
Clinical Relevance: The fibers of the anterior band of the IGHL provide a useful arthroscopic anatomic landmark for the direction of anterior capsulorrhaphy.
Background: Although previous biomechanical research has demonstrated the superiority of the suture-bridge rotator cuff repair over double-row repair from a mechanical point of view, no articles have described the structural and functional outcomes of this type of procedure.
Hypothesis: The structural and functional outcomes after arthroscopic rotator cuff repair may be different between the single-row, double-row, and combined double-row and suture-bridge (compression double-row) techniques.
Study Design: Cohort study; Level of evidence, 3.
Methods: There were 206 shoulders in 201 patients with full-thickness rotator cuff tears that underwent arthroscopic rotator cuff repair. Eleven patients were lost to follow-up. Sixty-five shoulders were repaired using the single-row, 23 shoulders using the double-row, and 107 shoulders using the compression double-row techniques. Clinical outcomes were evaluated at an average of 38.5 months (range, 24-74 months) after rotator cuff repair. Postoperative cuff integrity was determined using Sugaya’s classification of magnetic resonance imaging (MRI).
Results: The retear rates after arthroscopic rotator cuff repair were 10.8%, 26.1%, and 4.7%, respectively, for the single-row, double-row, and compression double-row techniques. In the subcategory of large and massive rotator cuff tears, the retear rate in the compression double-row group (3 of 40 shoulders, 7.5%) was significantly less than those in the single-row group (5 of 8 shoulders, 62.5%, P < .001) and the double-row group (5 of 12 shoulders, 41.7%, P < .01). Postoperative clinical outcomes in patients with a retear were significantly lower than those in patients without a retear for all 3 techniques.
Conclusion: The additional suture bridges decreased the retear rate for large and massive tears. The combination of the double-row and suture-bridge techniques, which had the lowest rate of postoperative retear, is an effective option for arthroscopic repair of the rotator cuff tendons because the postoperative functional outcome in patients with a retear is inferior to that without retear.
Background: Arthroscopic procedures for reconstruction of acromioclavicular (AC) joint separations are increasingly used in clinical practice. Multiple surgical techniques exist, but there are still few data on biomechanical performances of commonly used arthroscopic techniques and fixation methods.
Hypothesis: Single and double clavicular tunnel reconstructions show comparable primary stability with a modified Weaver-Dunn procedure, and double tunnel constructs show superior horizontal stability.
Study Design: Controlled laboratory study.
Methods: The AC joints of 40 cadaveric shoulders were tested for anterior, posterior, and superior translation (70-N load) and maximal load to failure (superior) with the MTS 858 Bionix II Servohydraulic testing system. Shoulders were assigned to 4 groups: (1) native (n = 18), (2) coracoclavicular (CC) reconstruction with 1 clavicular and 1 coracoid tunnel (SCT) fixed with a suture pulley and 2 buttons (n = 8), (3) CC reconstruction with 2 clavicular and 1 coracoid tunnel (DCT) fixed with a suture pulley and 3 buttons (n = 8), and (4) modified Weaver-Dunn reconstruction (n = 6).
Results: Native specimens showed a mean anterior translation of 7.92 mm (±1.69 mm), a mean posterior translation of 7.84 mm (±2.09 mm), and a superior translation of 4.28 mm (±1.81 mm). Maximal load to failure was 579.44 N (±148.01 N). The SCT technique showed a mean anterior translation of 5.81 mm (±1.16 mm), posterior translation of 8.30 mm (±1.94 mm), and a superior translation of 2.28 mm (±0.52 mm). The maximal load to failure was 591.35 N (±231.17 N). Anterior and superior translations were significantly less compared with the native specimen (P = .005 and P = .003). The DCT technique had an anterior translation of 4.68 mm (±0.6 mm), posterior translation of 6.85 mm (±0.83 mm), and superior translation of 2.09 mm (±0.86 mm). The mean maximal load to failure was 651.16 N (±226.93 N). Anterior and superior translations were significantly less compared with the native specimens (P = .000 and P = .001). No statistically significant differences were shown between SCT and DCT reconstruction for all measurements (P > .05). One reconstruction of the modified Weaver-Dunn procedure failed directly after mounting it into the testing device. The remaining 5 showed a mean anterior translation of 11.36 mm (±3.17 mm), a mean posterior translation of 13.51 mm (±2.21 mm), and a mean superior translation of 3.31 mm (±0.47 mm). Anterior and posterior translations were significantly increased compared with the native specimen (P = .019 and P = .000). The mean maximal load to failure measured 311.13 N (±52.2 N) and was significantly less compared with the native specimen (P = .000). The Weaver-Dunn technique showed significantly less maximal load to failure and more anterior and posterior translation compared with SCT and DCT (P ≤ .05).
Conclusion: Isolated reconstruction of the CC ligaments using single and double clavicular tunnel techniques results in a high load to failure for superior translation, which is equal to the native stability, and less translation in all 3 directions as well as higher superior stability when compared with the modified Weaver-Dunn procedure. A potential drawback is the risk of coracoid fracture, as the high load to failure of the device may exceed load to failure of cortical bone prior to device breakage.
Clinical Relevance: Single clavicular tunnel arthroscopic reconstructions of the coracoacromial ligaments show good biomechanical results.
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° of abduction, (3) posterior and anterior translation at neutral rotation (15 N and 25 N), (4) anterior translation at 90° of abduction and external rotation (Group 1; 15 N and 25 N), (5) posterior translation at 90° 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 capsulo-labral 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° 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.
