Zimmermann J, Grüninger P, Babians A, Zingg U
Department of Surgery, Limmattal Hospital, 8952 Schlieren, Switzerland.
Trauma Case Rep. 2021 Apr 23;33:100481. doi: 10.1016/j.tcr.2021.100481. eCollection 2021 Jun.
Inferior dislocation of the patella is a rare cause of a blocked knee and occurs typically in elderly patients. In most cases the mechanism is an osteophyte on the superior pole of the patella that becomes entrapped into the femoral trochlea, keeping the patella horizontally rotated and inferior localized. Advanced age and osteoarthritic changes of the knee are the main risk factors. Reduction should be performed under general anesthesia. We describe a case of an elderly lady with a type II inferior patella dislocation after direct blunt trauma. The therapy entailed reduction, knee arthroscopy, arthroscopic resection of osteophytes and smoothening of the articular surface. No recurrence occurred and range of motion was satisfactory at time of follow-up.
髌骨下脱位是膝关节交锁的罕见原因，通常发生于老年患者。在大多数情况下，其机制是髌骨上极的骨赘嵌入股骨滑车，使髌骨保持水平旋转并位于下方。高龄和膝关节的骨关节炎改变是主要危险因素。复位应在全身麻醉下进行。我们描述了一例老年女性在直接钝性创伤后发生II型髌骨下脱位的病例。治疗包括复位、膝关节镜检查、关节镜下骨赘切除和关节面平整。随访时未出现复发，活动范围令人满意。
