Clinical and radiological factors associated with recurrent shoulder dislocation after conservative treatment of traumatic primary anterior shoulder dislocation

The aim of this study is to evaluate the clinical and radiological factors affecting the development of recurrent shoulder dislocation in patients who have been followed up with conservative treatment after the traumatic primary anterior shoulder dislocation (TPASD), and to identify patient subgroups at high risk of recurrence.

Fifty-four patients (40 males and 14 females) aged 18-65 years who presented with first-time traumatic anterior shoulder dislocation and were treated conservatively were retrospectively evaluated. Patients with and without recurrent instability during a minimum follow-up of 12 months were compared regarding age, sex, affected side, Bankart lesion, bony Bankart lesion, greater tuberosity fracture, rotator cuff tear, Hill-Sachs lesion, Hill-Sachs lesion depth, glenoid version, and rotator interval width. Multivariable logistic regression analysis was performed to identify independent predictors of recurrent instability.

The recurrence rate was 46.3% after a minimum follow-up of 12 months. Univariate analysis demonstrated significant associations between recurrent instability and younger age, male sex, the presence of bony Bankart lesions, the presence and depth of Hill-Sachs lesions, and the absence of rotator cuff tears. No significant differences were observed regarding affected side, Bankart lesions, greater tuberosity fractures, glenoid version, or rotator interval width. In multivariable logistic regression analysis, the presence of a Hill-Sachs lesion remained an independent predictor of recurrent instability (OR 7.88, 95% CI 1.77-35.08, p = 0.007).

Recurrent instability following conservative treatment of first-time traumatic anterior shoulder dislocation is strongly associated with structural bone defects. Although younger age and male sex were associated with recurrence in univariate analyses, multivariable analysis identified the presence of a Hill-Sachs lesion as the strongest independent predictor of recurrent instability. Detailed radiological assessment may therefore facilitate risk stratification and treatment decision-making following TPASD.