Morphometric analysis of the effect of scapula stabilization on obstetric brachial plexus paralysis patients

Scapular position and size deficiency is evident in obstetric brachial plexus paralysis (OBPP) patients due to the absence of balanced muscular forces acting on the scapula. Scapula stabilization (SS) procedures aim to restore a balanced musculature and anatomic position and to augment shoulder function and enhance developmental potential.

Retrospective chart review of 106 patients with OBPP between March 1979 and March 2007 was performed. Forty-one female and 27 male were included in the study. In 38 patients, the paralysis was global, 13 had Erb's paralysis with C7 root involvement; in 18 patients, the lesion was limited to C5 and C6. X-rays were evaluated, and scapula dimensions were manually measured at several stages. Shoulder abduction (SA) and external rotation (SER) outcomes were also recorded.

Mean improvement was 85.68° in shoulder abduction and 36.74° in shoulder external rotation. SA and SER improvement was significantly better in those who underwent SS procedures compared to those who did not (mean improvement was increased by 9.15° and 8.54°, respectively). Improvement was noted in all scapular dimensions, in all groups, postoperatively. However, the mean improvement in scapular height, big width, small width, and oblique axis discrepancies was 4.92, 14.04, 12.66, and 13.89 %, respectively, higher in patients who underwent SS procedures compared to those who did not.

Dimensional discrepancies and functional outcomes are improved by SS procedures. Maximal results are attained in patients who have undergone both primary and secondary shoulder reconstruction before age 2.