Shoulder isokinetic profile after Latarjet's technique

The following procedures were performed on 23 patients (15 of them males): a shoulder strength isokinetic evaluation of the internal (IR) and external (ER) rotators (with the shoulder 45 degrees and 90 degrees abducted in the frontal plane), a passive range of motion measurement, a Rowe score and a scanner exam. These patients had previously undergone open coracoid transposition using Latarjet's technique according to two different surgical procedures: a tenotomy (n = 6) or a splitting (n = 17) of the subscapularis muscle approach. In our retrospective study, the period of time between surgery and assessment was an average of 30 months. The average Rowe score was 89 on a scale of 100, with a good pattern of passive mobility. The isokinetic data showed an external rotator weakness (in all testing conditions), most notably at 60 degrees/s in 45 degrees of abduction position (p < 0.001 - 12.2%). By contrast, the internal rotators were only significantly (p < 0.05) impaired (8.2%) at 60 degrees/s in the 90 degrees of abduction position. Consequently, the external/internal rotator ratio (ERAR) was reduced in the 45 degrees of abduction installation only, highlighting the influence of testing position on the isokinetic results and therefore on the shoulder muscle profile. Surgical technique comparison revealed that only the tenotomy procedure entailed an IR deficit (17%) measured at 45 degrees of abduction installation. Shoulders (n = 5) presenting a fatty degeneration of the subscapularis muscle >= stage II (corresponding exclusively to the tenotomy surgical approach) showed an internal rotator weakness (19%) measured in 45 degrees of abduction. Patients (n = 13) without subscapularis fatty degradation (corresponding solely to the horizontal splitting approach) did not develop any impairment of strength in internal rotators. Furthermore, no correlation between mobility pattern and strength impairment was observed in the study.