Parosteal osteosarcoma of the thumb: A case report and literature review.

Parosteal osteosarcoma (PO) is a rare malignant tumor arising from the surface of the bone. Locations in the hand are even more exceptional. This low-grade osteosarcoma shows non-specific clinical and radiological presentation, making diagnosis challenging. Moreover, histologic examination is extremely difficult and can easily lead to misdiagnosis. We report the case of a 21-year-old woman who presented PO of the right thumb, initially diagnosed as a "benign exostosis" 9 years previously. En-bloc resection followed by reconstruction using a free corticocancellous iliac crest autograft provided good esthetic and functional outcome. No recurrence occurred at 2 years' follow-up. Our literature review confirmed the rarity of PO of the hand, with only 8 cases reported in the past 60 years. Amputation was the main treatment, but some authors reported limb-sparing surgery. The present result and those in the literature review support conservative surgery when feasible, with little recurrence and better functional and esthetic results. These rare tumors should not be misdiagnosed, and should be treated in specialized centers to optimize outcome.

Three concomitant locked finger metacarpophalangeal joints caused by degenerative metacarpal heads: Case report.

A locked metacarpophalangeal joint (LMCP) is a rare condition often confused with trigger finger. Its causes are numerous and typically divided into two broad categories: acquired LMCP in younger patients, and degenerative LMCP in older patients. This pathology usually affects only one MCP. Even though several external reduction techniques have been described, the main risk of non-surgical reduction treatment is recurrence. Thus, its management is most often surgical. We report the case of a 60-year-old woman with 3 simultaneous LMCP (3rd, 4th, and 5th rays of the left hand) due to degenerative metacarpal heads. Surgical treatment was performed and found that locking was due to entrapment of the radial collateral ligament on metacarpal head osteophytes. Full extension was regained at the end of the surgery. The follow-up was uneventful, no recurrence occurred. This case highlights the need for careful examination to prevent medical and surgical wandering for a rare but well-described and easy to treat condition.