Published online Dec 18, 2025. doi: 10.5312/wjo.v16.i12.111602
Revised: August 4, 2025
Accepted: October 29, 2025
Published online: December 18, 2025
Processing time: 166 Days and 17.5 Hours
Inferior intra-articular patella dislocation is rare and comprises horizontal (type 1) and the more common vertical (type 2) dislocations in young and elderly patients respectively. In this case report, we describe a case of an elderly patient who pre
A 75-year-old woman presented with a right knee fixed flexion deformity after a fall. Preoperative imaging confirmed a vertical intra-articular patella dislocation with a femoral trochlear osteochondral defect and lax though grossly intact patella tendon. Closed reduction was performed under general anaesthesia. Knee arthroscopy confirmed the presence of a femoral trochlear osteochondral defect whose edges were subsequently smoothed and there was debridement of scant debris with thorough irrigation of the joint. Postoperative imaging demonstrated anatomical alignment, however, there was a new nondisplaced medial femoral trochlear. The patient however was able to mobilise well in a range of motion brace set at 0-30 degrees and was discharged 1-day post operatively.
Inferior patella dislocation is rare and this article highlights its types and imaging features which determine the most appropriate management.
Core Tip: Assessment of inferior patella dislocation should focus on the patella position, any fractures and the condition of the extensor mechanism. Closed reduction is possible in type 2 injuries (vertical orientation from osteophyte locking), however, success is dependent on the depth and size of the osteochondral defect and degree of patella rotation. Open reduction is recommended for type 1 (horizontal type) due to associated soft tissue injury which can be repaired. In type 2 injuries open reduction is recommended with large osteochondral defects requiring smoothing and or debridement, large osteophytes requiring resection or removal of intra-articular loose bodies.