腱板断裂を伴わない中高齢者の反復性肩関節前方脱臼の病態の特徴

抄録

Most of the studies on recurrent anterior shoulder dislocation in older patients have shown pathologies related to rotator cuff tears. However, the pathologies focusing on the anterior capsular mechanism of older patients without rotator cuff tears have not been well elucidated. The purpose of this study was to assess the pathological features of the anterior capsular mechanism in older patients with recurrent anterior shoulder dislocation in the absence of rotator cuff tears. Between 2002 and 2007, 38 patients (40 shoulders, 12 males and 26 females) aged more than 40 years underwent arthroscopic treatments for recurrent anterior shoulder dislocation. There were no patients with rotator cuff tears. The average age at the operation was 52 (40-72)years old. The average age at the time of initial dislocation was 30.8 (9-70) years old. Patients were divided into 2 groups by age of the initial dislocation. Group A (<40 y.o.) was 31 shoulders, Group B (>40 y.o.) was 9 shoulders. We performed arthroscopic evaluation of anterior capsular mechanism on all the patients. Bankart lesion was seen in 32 shoulders (Group A: 87.1%, Group B: 55.6%). Midsubstance complete tear of IGHL (IGHL tear) was seen in 14 shoulders (A: 29%, B:55.6%). HAGL lesion was seen in 3 shoulders (A: 6.5%, B: 11.1%). According to all the pathologies, isolated Bankart lesion was seen in 21 shoulders (A: 65.4%, B: 33.3%). Bankart lesion with IGHL tear was seen in 9 shoulders (A: 22.6%, B: 22.2%). Isolated IGHL was seen in 5 shoulders (A: 6.5%, B: 33.3%). In comparison with younger patients and older patients, the prevalence of the isolated Bankart lesion was low, but the prevalence of the IGHL tear was high in older patients. We should keep in mind the existence of the IGHL tear in older patients and evaluate the whole anterior capsular mechanism meticulously.