Glenohumeral joint motion after subscapularis tendon repair: an analysis of cadaver shoulder models

Abstract

BackgroundAs for the surgical treatment of the rotator cuff tears, the subscapularis tendon tears have recently received much attention for the mini-open or arthroscopic repair. The results of surgical repair for the subscapularis tendon tear are satisfactory, but the range of external rotation is reported to be restricted after the repair. The purpose of this study was to evaluate the range of glenohumeral joint motion after repairs of various sizes of subscapularis tendon tears.MethodsUsing eight fresh frozen human cadaveric shoulders (mean age at death, 81.5 years), three sizes of subscapularis tendon tear (small, medium, and large) were made and then repaired. With the scapula fixed to the wooden jig, the end-range of glenohumeral motion was measured with passive movement applied through 1.0-Nm torque in the directions of scapular elevation, flexion, abduction, extension, horizontal abduction, and horizontal adduction. The passive end-ranges of external and internal rotation in various positions with rotational torque of 1.0 Nm were also measured. Differences in the ranges among the three type tears were analyzed.ResultsAs tear size increased, range of glenohumeral motion in horizontal abduction after repair decreased gradually and was significantly decreased with the large size tear (P < 0.01). The end-range of external rotation decreased progressively with increasing tear size in every glenohumeral position. The prominent decrease in external rotation (around 40° reduction from intact shoulders) was observed in shoulders after repair of large size tear at 30° to 60° of scapular elevation and abduction.ConclusionsAs the size of the subscapularis tendon tear increased, the passive ranges of horizontal abduction and external rotation of the glenohumeral joint after repair decreased significantly. In shoulders with a subscapularis tendon tear, it is necessary to consider the reduction of external rotation depending on tear size.

Effect of intraarticular pressure on glenohumeral kinematics during a simulated abduction motion: a cadaveric study

“…The skin and the superficial musculature were removed, while maintaining the integrity of the RC muscles and the joint capsule, and the clavicle was disarticulated at the acromioclavicular joint [ 14 ]. The remaining tissue was kept moist with physiologic 0.9% saline throughout testing [ 30 , 31 ]. The RC muscles were elevated off of the scapula, and sutures were placed through the free ends between two layers of a nylon belt using a locking Krackow stitch.…”

Análisis e influencia de los sistemas de referencia en la cinemática del hombro

“…El primero en describir este movimiento fue Inman y colaboradores en 1944 [3]. Posteriormente muchos investigadores han medido RH tanto para hombros normales como con patologías [4][5][6][7][8]. Se puede apreciar que para pacientes con patologías es relevante la detección de las pequeñas variaciones en los movimientos, por lo que se necesita de un procedimiento preciso; ello permitiría establecer la influencia del tratamiento en la recuperación.…”

Combined Subscapularis Tears in Massive Posterosuperior Rotator Cuff Tears

“…Biomechanically, an increase in the size of a subscapularis tendon tear led to decreased passive range of external rotation after the repair. 49 Considering the frequent occurrence of subscapularis tears with massive tears, which is known to range from 24% to 69%, it is assumed that clinical outcomes after repair of massive tears may be affected by the presence or size of subscapularis tears. 3,19,30,35,44 Nevertheless, most previous studies on massive rotator cuff tears have focused on covering supraspinatus and infraspinatus rotator cuff defects with remnant tissues or allograft patches without addressing the outcomes of tears extending to the subscapularis tendon.…”