Primary Synovial Osteochondromatosis of the Hip Joint Treated with Arthroscopic-assisted Mini-open Surgery-Two Case Reports

INTRODUCTION: Primary synovial osteochondromatosis of the hip joint is a rare condition. It is characterized by the presence of multiple intra-articular loose bodies and can result in mechanical symptoms, even causing degenerative change. Surgical treatment is indicated for synovial osteochondromatosis of the hip joint. However, the optimal approaches for successful surgical management are still controversial. CASE REPORT: We report two cases with primary synovial osteochondromatosis of the hip joint where arthroscopic-assisted mini-open surgical treatmentwas performed. The posterior approach was used, and a minimal arthrotomy was performed with preservation of bloody supplement of thefemoral head. With the assistance of an arthroscope, synovectomy, debridement, and loose body removal were completed without dislocating the femoral head. The follow-up duration was 5years and 2.5 years, respectively. There were no perioperative or post-operative complications. At the latest follow-up, the patients remain symptom free with no radiographic evidence of recurrence. CONCLUSIONS: Our arthroscopic-assisted mini-open method could achieve the goals of extensive synovectomy, debridement, and loose body removal, thus reducing the recurrence rate. This method avoids dislocation of the femoral head, thus reducing the occurrence of surgical complications.