[Congenital scaphotrapezial synostosis associated with a carpal tunnel syndrome: a case report]

Bilateral STT Arthrodesis in a Young Patient with Occult Proximal Row Coalition

Background  Carpal coalitions have an incidence of 0.1 to 1% in Caucasians and up to 8 to 9% in African populations. They rarely cause clinical problems requiring investigation or treatment, but are commonly identified on imaging obtained for other indications. Case Description  We report a case of a 35-year-old male with progressive degenerative change of incomplete coalitions of the scaphotrapeziotrapezoid joint (STT) in the presence of bilateral complete osseous lunate-triquetral coalitions (Minnaar type 4). He was successfully treated with staged bilateral arthrodesis with excellent symptom resolution and preservation of function. Literature Review  In patients with isolated STT coalition six reports of surgery exist, two of which were for arthrodesis. This is the first described case of STT arthrodesis in a patient with coexistent lunate-triquetral coalition. Clinical Relevance  The STT arthrodesis remains a safe and effective treatment for STT pain even in cases of occult carpal coalition. Functional range of movement was well preserved. Level of evidence  This is a Level V study.

Unilateral fusion of the scaphoid and the trapezium

Fusion of the carpal bones is a rare anatomical abnormality, caused by a defect in the separation and cavitation during embryonic development. It has a prevalence of about 0.1% and most of the time, patients do not present with symptoms. Symptoms are usually caused by wear and tear of the ligaments attached to the fused carpal fragments. We present a case in which a woman aged 36 years experiences pain caused by a lunato-triquetral instability which in turn is caused by a unilateral complete fusion of the scaphoid and the trapezium. A unilateral complete fusion of the scaphoid and trapezium has not been reported before.