TY - JOUR
T1 - The effect of subscapularis muscle contraction on coaptation of anteroinferior glenohumeral ligament–labrum complex after Bankart repair
AU - Itoigawa, Yoshiaki
AU - Hooke, Alexander W.
AU - Sperling, John W.
AU - Steinmann, Scott P.
AU - Zhao, Kristin D.
AU - Itoi, Eiji
AU - An, Kai Nan
N1 - Funding Information:
This study was supported by the Alumni Scholarship Juntendo University School of Medicine., The funders were the Division of Orthopedic Research, Mayo Clinic, and the Alumni Scholarship of Juntendo University School of Medicine. The funding sources had no role in the investigation or preparation of the manuscript., The authors confirm that there is no potential conflict of interest, including employment, consultancies, stock ownership, honoraria, and paid expert testimony and patent applications, influencing this work.
Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2019/3/6
Y1 - 2019/3/6
N2 - Facilitation of healing is important for the anteroinferior glenohumeral ligament–labrum complex (AIGHL-LC) after Bankart repair in shoulder dislocation. The purpose of this study was to investigate the effect of subscapularis muscle loading on contact area and contact pressure between the subscapularis and AIGHL-LC and between the glenoid bone and the AIGHL-LC following Bankart repair. Twenty-two fresh-frozen cadaveric shoulders were used. They were attached to a shoulder-positioning device to which a compression force was applied. Loads applied to the supraspinatus, infraspinatus, and teres minor tendons were held constant. The loads applied to the subscapularis tendon were set at 0, 10, 20, and 30 Newton (N). Contact pressure and area between the subscapularis and the AIGHL-LC were measured with the arm at 4 rotational positions: 60° and 30° internal, neutral, and 30° external. After the Bankart lesion was created, the contact area and pressure between the AIGHL-LC and glenoid bone were measured while Bankart repair was performed with or without loading of the subscapularis. The contact area and pressures with 10, 20, and 30 N of subscapularis loadings were significantly greater than with 0 N of subscapularis loading at 60° internal rotation and 30° external rotation (P <.05). After Bankart repair, contact area and pressure with subscapularis loading between the AIGHL-LC and glenoid bone were significantly greater than without subscapularis loading (P <.01). We conclude that isometric contraction exercises of the subscapularis might facilitate healing of the AIGHL-LC after Bankart repair.
AB - Facilitation of healing is important for the anteroinferior glenohumeral ligament–labrum complex (AIGHL-LC) after Bankart repair in shoulder dislocation. The purpose of this study was to investigate the effect of subscapularis muscle loading on contact area and contact pressure between the subscapularis and AIGHL-LC and between the glenoid bone and the AIGHL-LC following Bankart repair. Twenty-two fresh-frozen cadaveric shoulders were used. They were attached to a shoulder-positioning device to which a compression force was applied. Loads applied to the supraspinatus, infraspinatus, and teres minor tendons were held constant. The loads applied to the subscapularis tendon were set at 0, 10, 20, and 30 Newton (N). Contact pressure and area between the subscapularis and the AIGHL-LC were measured with the arm at 4 rotational positions: 60° and 30° internal, neutral, and 30° external. After the Bankart lesion was created, the contact area and pressure between the AIGHL-LC and glenoid bone were measured while Bankart repair was performed with or without loading of the subscapularis. The contact area and pressures with 10, 20, and 30 N of subscapularis loadings were significantly greater than with 0 N of subscapularis loading at 60° internal rotation and 30° external rotation (P <.05). After Bankart repair, contact area and pressure with subscapularis loading between the AIGHL-LC and glenoid bone were significantly greater than without subscapularis loading (P <.01). We conclude that isometric contraction exercises of the subscapularis might facilitate healing of the AIGHL-LC after Bankart repair.
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U2 - 10.1016/j.jbiomech.2019.01.023
DO - 10.1016/j.jbiomech.2019.01.023
M3 - Article
C2 - 30691988
AN - SCOPUS:85060454864
SN - 0021-9290
VL - 85
SP - 134
EP - 140
JO - Journal of Biomechanics
JF - Journal of Biomechanics
ER -