Biomechanical comparison of acute Hill-Sachs reduction with remplissage to treat complex anterior instability

Abstract

Acute Hill-Sachs reduction represents a potential alternative method to remplissage for the treatment of an engaging Hill-Sachs lesion. This study biomechanically compared the stabilizing effects of an acute Hill-Sachs reduction technique and remplissage. Six cadaveric shoulders were tested. For the acute Hill-Sachs lesion, a unique model was used to create a 30% defect, compressing the subchondral bone while preserving the articular surface. Five scenarios were tested: intact specimen, bipolar lesion, Bankart repair, remplissage with Bankart repair, and Hill-Sachs reduction technique with Bankart repair. The Hill-Sachs lesion was reduced through a lateral cortical window with a bone tamp, and the subchondral void was filled with bone cement. At 90° of abduction and external rotation (ER), total translation was 11.6 ± 0.9 mm for the bipolar lesion. This was significantly reduced after remplissage (5.9 ± 1.1 mm; P < .001) and after Hill-Sachs reduction (4.7 ± 0.4 mm; P < .001). Compared with an isolated Bankart repair, the average ER loss after remplissage was 4° ± 4° (P = .65), and the average ER loss after Hill-Sachs reduction was 1° ± 3° (P = .99). Similar joint stability was conferred after both procedures, with minimal change in range of motion. Remplissage may still be the best way to address chronic Hill-Sachs lesions; however, the reduction technique is a more anatomic alternative and may be a potential option for treating an acutely engaging Hill-Sachs lesion.