Epileptic patients with anterior shoulder instability: are there specific bone lesions? A case control study.

ABSTRACT

HYPOTHESIS: Chronic epilepsy may cause important bipolar bony lesions. We aim to compare the specific pathoanatomic metrics of the bony lesions in chronic shoulder anterior instability that occur in patients with epilepsy vs. patients without epilepsy. METHODS: From 2006 to 2020, we included epileptic and nonepileptic patients with anterior recurrent shoulder instability. We randomly adjusted the patients of the 2 groups according to the sex, age, and type of management. We included 50 patients. For each included patient, we performed an in-depth analysis and comparison of the glenoid bone loss based on the computed tomography scan PICO method (patient/population, intervention, comparison and outcomes) using the best-fit circle; and the Hill-Sachs lesion the depth and width were given as a percentage of the humeral head diameter on an axial view. We also evaluated the engaging character of the involved lesion using the on-track vs. off-track analysis. Those characteristics were compared between the 2 groups. RESULTS: We found a glenoid bone loss in 32 patients. Glenoid bone loss was not significantly greater in patients with epilepsy (P = .052). A Hill-Sachs lesion was found in 42 patients (22 in the group with epilepsy and 20 in the group without epilepsy). Hill-Sachs lesions were significantly deeper and larger in the group with epilepsy (depth 22% vs. 9%, P < .001; width 43% vs. 28%, P = .003). In the group with epilepsy, 90% of the bone lesions were off-track vs. 30% in the group without epilepsy. Thus, the patients with epilepsy presented more engaging bony lesions than patients without epilepsy (P = .001) (OR = 23). CONCLUSIONS: In a population of patients with epilepsy who had shoulder instability, Hill-Sachs lesions are larger and deeper than in normal patients with shoulder instability. By contrast, there is no significant difference regarding the characteristics of the glenoid bone loss if present. This implies that bone lesions in instable shoulders of patients with epilepsy need at least a bony stabilization procedure on the humeral side in the majority of cases.