RESUMO
BACKGROUND: Previously reported outcomes after tendon transfers to reconstruct the subscapularis are unpredictable and often unsatisfactory, especially in the presence of anterior humeral head subluxation. We studied the anatomic feasibility of the lower trapezius and the rhomboid minor transfer to reconstruct irreparable tendon tears of the subscapularis. The aim of this study was to determine the feasibility of lower trapezius and rhomboid minor transfer to reconstruct irreparable subscapularis tendon tears. MATERIALS AND METHODS: We measured the tendons dimensions, muscles excursions, distances to pedicles, and dissection needed to complete a successful lower trapezius and/or rhomboid minor transfer to the subscapularis footprint in 10 cadaveric shoulders. The transferred muscles were detached distally, augmented with a semitendinosus and gracilis autograft, and passed anteriorly between the scapula and the subscapularis remnant through a small serratus window to reach the lesser tuberosity. The risk of pedicle compression was subjectively assessed in all cases. RESULTS: The trapezius and rhomboid tendons were asymmetric with an average length of 37.6 mm and 21.7 mm, an average width of 63 mm and 33.4 mm, respectively. The mean distances from each distal insertion to the lesser tuberosity were 109 mm for the trapezius and 144 mm for the rhomboid. Mean distances from tendon to pedicle were 57.9 mm and 33.1 mm, respectively. The mean size of the necessary serratus window was 49.4 mm, which was measured at maximal excursion achieved at maximal external rotation 90° representing two digitations. All of the tendon transfers were feasible, and the risk of pedicle compression was 20% for the trapezius and 10% for the rhomboid. Superior migration of the transfer was observed during passive external rotation if the insertion point was too high. CONCLUSIONS: Transfer of the lower trapezius and rhomboid minor to the lesser tuberosity to reconstruct an irreparable subscapularis tear is feasible without extensive dissection and with a low risk of nerve compression. We recommend not to transfer the rhomboid minor routinely, owing to the risk of tendon luxation after external rotation of the shoulder.
RESUMO
PURPOSE: To compare the stability and cost of the used implants in nonanatomic and anatomic acromioclavicular joint repair/reconstruction (ACCR) techniques tested in cadaveric shoulder biomechanical studies during the last decade. METHODS: A systematic review and meta-analysis were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and prospectively registered in PROSPERO. Two independent reviewers searched PubMed, Embase, and Virtual Health Library databases. Studies evaluating 3-direction stability under 70-N loads and load-to-failure protocols with servohydraulic testing systems were included. A meta-analysis of the mean differences of anterior, posterior, and superior direction; relative stability value in 3 directions; superior direction load-to-failure; stability/cost index; and load-to-failure/cost index was performed using a continuous random-effects model and 95% confidence interval. RESULTS: Eighteen articles were included. Both non-ACCR and ACCR techniques exceeded the minimum acceptable threshold of stability and load-to-failure. ACCR techniques were biomechanically better in terms of anterior stability (P = .04) and relative stability value (mean difference 64.08%, P = .015). However, supraphysiological stability and failure loads were achieved with non-ACCR techniques at a lower cost of implants. Techniques combining 2 clavicular tunnels separated by at least 10 mm, a mean of 2 sutures, and/or suture tapes had the greatest stability/cost index and load-to-failure/cost index among the included techniques (confidence interval 99%). CONCLUSIONS: Non-ACCR and ACCR techniques exceeded the minimum acceptable threshold of stability and failure loads in controlled biomechanical testing. However, non-ACCR and techniques combining 2 clavicular tunnels separated by at least 10 mm, a mean of 2 sutures, and/or suture tapes provide supraphysiologic stability and failure loads at a lower cost of implants. CLINICAL RELEVANCE: Non-ACCR and suture-based techniques may provide more cost-effective and greater value treatment for acromioclavicular joint injury and could be considered in the surgical management of normal activity individuals and cost-sensitive populations.