Synovial cysts of the hip joint: a single-center experience

BACKGROUND: Synovial cyst of the hip joint is a rare clinical condition in need of evidence-based guidelines for its diagnosis and management. Normally, synovial cyst of the hip joint requires no treatment, but when it intrudes into surrounding structures, various clinical symptoms appear. Because of its rarity, a symptomatic synovial cyst is often confounded with a tumor as a space-occupying lesion or with other diseases, depending on its various clinical presentations. Therefore, guidelines for the precise diagnosis and appropriate management for synovial cyst of the hip joint are required. METHODS: We retrospectively studied 7 cases of symptomatic synovial cyst of the hip joint, some of which showed lower limb edema due to mass effect. We compared physical exam findings on presentation, imaging findings, and size and location of the cyst. RESULTS: All cases were managed successfully with surgical excision. We found that, instead of the size of the cyst, the location of the cyst was an important contributor to venous compression. The recurrence rate was 0%, and some patients have significantly long follow-up of 2 years, 4 years, 6 years and 10 years, respectively. CONCLUSIONS: For symptomatic synovial cyst of the hip joint, surgical excision can successfully resolve the symptoms without recurrence. This retrospective study discusses the clinical presentations, diagnostic approaches, and surgical treatment of symptomatic synovial cyst of the hip joint, hence shedding more light on the clinical management of this condition.