RESUMEN
Background: Coracoacromial ligament (CAL) degeneration is thought to be a factor in external impingement in bursal-sided rotator cuff tears, but CAL release is associated with adverse effects. Purpose: To investigate the association between CAL degeneration and the patterns of massive rotator cuff tears using multiple modalities and to assess the effect of CAL degeneration on supraspinatus tendon retear rates. Study Design: Cohort study; Level of evidence, 2. Methods: The authors prospectively recruited 44 patients who had undergone arthroscopic rotator cuff repair without acromioplasty or CAL release. Preoperative radiographs and magnetic resonance imaging (MRI) scans were reviewed to determine acromial morphology and CAL thickness, respectively. Rotator cuff tears were categorized as isolated supraspinatus or massive (involvement of ≥2 tendons), with massive tears categorized using the Collin classification. Acromial degeneration was analyzed using the Copeland-Levy classification. The CAL was biopsied intraoperatively and histologically analyzed using the Bonar score. At 6-month follow-up, the integrity of the repaired supraspinatus tendon was analyzed on MRI using the Sugaya classification. Finally, the associations among CAL degeneration, rotator cuff tear pattern, and arthroscopic grading were investigated. Results: Patients with Collin type B rotator cuff tear had significantly higher CAL Bonar scores than those with Collin type A or isolated supraspinatus tears (10.0 vs 6.8 and 3.4; P = .03 and P < .001, respectively). Patients with a degenerative acromial undersurface of Copeland-Levy stage 2 or 3 had CALs with significantly higher Bonar scores than those with an intact acromial undersurface (8.4 and 8.2 vs 3.5; P = .034 and P = .027, respectively). The CAL Bonar scores of patients with different stages of the 6-month postoperative Sugaya classification were comparable (6.5, 7.2, 8.0, and 7.8 for stages 1, 2, 3, and 4, respectively; P = .751). Conclusion: CAL degeneration was more severe in anterosuperior-type massive rotator cuff tears. Interestingly, even without acromioplasty, the severity of CAL degeneration did not affect the retear rate of the supraspinatus tendon.
RESUMEN
Background: Despite the increasing prevalence of tape-type sutures, whether internal knotless anchors can consistently affix tape-type sutures has not been thoroughly investigated. Purpose: To evaluate whether substituting tape-type sutures for conventional sutures influences the suture-holding strength of internal knotless anchors. Study Design: Controlled laboratory study. Level of evidence, 5. Methods: A total of 3 internal knotless anchors were tested: a spiral core clamping anchor (Footprint Ultra PK), a winged clamping anchor (PopLok), and a spooling anchor (ReelX STT). Four constructs were compared for each type of anchor, with the anchor double or quadruple loaded with tape-type sutures or conventional sutures. The testing protocol comprised preloading suture tension to 10 N; cyclic loading, in which tension increased in increments of 10 N from 10 to 90 N; and a load-to-failure stage set at a speed of 0.5 mm/s. The clinical failure load (CFL) was defined as suture slippage of ≥3 mm. Also, 1-way analysis of variance and power analysis were used to compare the CFLs of the constructs. Results: For the quadruple-loaded spiral core clamping anchors, a significant reduction in CFLs was seen with conventional sutures over tape-type sutures (138.10 ± 4.73 vs 80.00 ± 12.25 N, respectively; P < .001). This reduction was not observed under the double-loaded condition (conventional vs tape type: 76.00 ± 5.48 vs 80.00 ± 10.00 N, respectively). Substitution of the suture materials did not significantly reduce the CFLs for the winged clamping anchors (conventional vs tape type: 40.00 ± 10.00 vs 30.00 ± 7.07 N for double loaded, respectively, and 64.00 ± 13.41 vs 50.00 ± 10.00 N for quadruple loaded, respectively) or the spooling anchors (conventional vs tape type: 62.00 ± 19.23 vs 56.32 ± 20.20N for double loaded, respectively, and 72.00 ± 21.68 vs 84.00 ± 13.42 N for quadruple loaded, respectively). Conclusion: Substituting tape-type sutures for conventional sutures increased the CFLs of some internal knotless anchors. With specific suture-anchor combinations, quadruple-loaded conventional suture anchors had CFLs higher than those of double-loaded conventional suture anchors. Clinical Relevance: When multiple tape-type sutures are used in conjunction with a clamping anchor, clinicians should note a possible reduction in CFLs and resultant early suture slippage.
RESUMEN
PURPOSE: To compare the biomechanical characteristics of the interconnected knotless anchor (IKA) fixation with the double knotless anchor (DKA) and interference screw (IS) fixation in the suprapectoral biceps tenodesis. METHODS: In total, 24 fresh-frozen human cadaveric shoulders (mean age, 67.3 ± 6 years) were used for the study. All the specimens were randomly divided into 3 experimental biceps tenodesis groups (n = 8): IKA, DKA, and IS. After tenodesis, each specimen was preloaded at 5 N for 2 minutes, followed by a cyclic loading test from 5 to 70 N for 500 load cycles. Finally, a destructive axial load to failure test (1 mm/s) was performed. All the values, including ultimate failure load, stiffness, cyclic displacement, and mode of failure were evaluated. RESULTS: The IKA provided the highest construct stiffness (38.9 ± 7.7 N/mm) and ultimate failure load (288.3 ± 47.6 N), the results for which were statistically better than the corresponding results in the IS and DKA groups. In terms of cyclic displacement, there were no statistical differences among the 3 fixation constructs. The most common failure mode was biceps tendon tearing in IS group (7/8) and IKA group (8/8). In the contrast, suture slippage accounted for the most common failure mode in DKA. CONCLUSIONS: In suprapectoral bicep tenodesis, IKA fixation appears to offer improved construct stiffness and ultimate failure load while maintaining comparable suture slippage as compared with IS fixation or DKA fixation in the current biomechanical study. CLINICAL RELEVANCE: The IKA fixation compares favorably with other techniques and could be an alternative clinical option for suprapectoral biceps tenodesis.
