The novel arthroscopic subscapular sling procedure grants better stability than an arthroscopic Bankart repair in a cadaveric study

Abstract

Purpose This novel arthroscopic subscapular sling procedure stabilizes the shoulder using a semitendinosus graft to create a sling around the subscapular tendon, which provides both static and dynamic stability. The aim of the study was to evaluate the biomechanical stability of the subscapular sling procedure in human cadaveric shoulders. The hypothesis was that the sling offers an equal stabilizing effect and range of motion compared to an arthroscopic Bankart repair. Methods Sixteen shoulders were investigated using an industrial robot-based testing platform and four different conditions: the physiologically intact shoulder, after creating a Bankart lesion, after arthroscopic Bankart repair, and finally after applying the subscapular sling procedure using a semitendinosus tendon graft. Joint translation and external rotation were evaluated for each condition. ResultsThe results show improved stability in the shoulders with the subscapular sling. The robot testing revealed a significant reduction in translation in anterior and anterior-inferior directions compared to the arthroscopic Bankart repair. None of the shoulders were dislocated by forced manual abduction and external rotation. No difficulties were encountered in performing the arthroscopic subscapular sling procedure. Thorough postoperative anatomical dissection showed no alterations to structures at risk. ConclusionThe biomechanical results show increased stability with the use of the subscapular sling method.

The novel arthroscopic subscapular quadriceps tendon–bone sling procedure provides increased stability in shoulder cadavers with severe glenoid bone loss

“…The QTB sling may, therefore, be a safe alternative to the Latarjet procedure and other bony transport procedures. The subscapular sling does not alter the anatomy regarding the conjoined tendon, coracoid and nerves [37]; the Latarjet technique may, therefore, serve as a “salvage procedure” in case of failure.…”

“…In contrast to the subscapular tenodesis performed in the Putti–Platt procedure [36] and other techniques described recently [7, 24], the subscapular tendon–bone sling achieves a combination of both dynamic and static stabilization without a tenodesis of the subscapular tendon [20] which may prevent over constraint and subsequently, secondary arthrosis. In a previous study of the ST subscapular sling [37], the graft was fixated in 0° of abduction and neutral rotation and a significant reduction in external rotational range of motion at 60° of abduction was observed. To prevent this in the present study; the sling was attached in 30° of abduction and 20° of external rotation of the arm, which assured that no tension was applied to the subscapular tendon.…”

“…Statistical analyses were carried out using the R software package (version 3.3.2; R Foundation for Statistical Computing). The sample size was calculated based on data from the previous study of the subscapular sling [37] by use of the software G Power and Stata. The results were: with a mean of 15.9 mm (SD 8.1) of translation (anterior direction) in the lesion condition, and 7.5 mm (SD 3.8) in the sling condition, with a 95% CI and a power of 90, the required sample size ( N ) is 11.…”

“…When performing the ST sling procedure, all the instrument handling takes place lateral to the conjoined tendon, which potentially reduces the risk of harm to nerves and vessels. As a consequence of the previous convincing biomechanical investigations of this new method [37], we decided to further explore the potential of an arthroscopic subscapular sling procedure which utilizes a quadriceps tendon bone (QTB) graft. The aim of this study was to biomechanically evaluate this new stabilizing technique on human cadaveric shoulders in a glenoid bone loss model.…”

Dynamic and Static Stabilization of Anterior Shoulder Instability With the Subscapular Sling Procedure

“…[6][7][8][9][10][11] The potential for better treatment options led to the development of the subscapular sling with a semitendinosus (ST) graft. 12,13 Feasibility and biomechanical cadaveric studies have been performed, 12,13 and a clinical pilot study of the subscapular sling shows promising preliminary results. The purpose of this paper is to present the surgical procedures involved in the subscapular sling method with an ST graft.…”