Repair of large supraspinatus rotator-cuff defects by infraspinatus and subscapularis tendon transfers in a cadaver model

Transosseous repair of a supraspinatus tendon (SSP) defect (Patte size II) can be difficult if the tendon is retracted and the muscle atrophied. In this situation alternatives are margin convergence techniques, local tendon transfers or distant tendon transfers in massive tears. The object of this study was to compare two local tendon transfers in terms of the feasibility of the shift, the area covered by the shift and the force needed to accomplish the shift. Thirteen fresh-frozen cadaver shoulders were used. First a supraspinatus defect extending to the apex of the humeral head (Patte size II) was created. Transosseous repair was attempted with the infraspintus (ISP) and with the subscapularis (SCP) in all cases; repair was successful in all ISP cases, while use of the SCP resulted in a successful repair in only 8 of the 13 (61.5%). A significantly (P=0.012) larger defect area was covered by the ISP transfer than by the SCP shift: 89.7±8.5% versus 31.2±31.1% of the original defect, respectively. The tensile force needed to accomplish the shift was significantly (P=0.004) lower when the ISP was used (15±11 N) than with the SCP (37.1±15 N). In this cadaver model the ISP shift proved more favourable than the SCP shift for covering a Patte size II SSP defect.