Abstract
CONTEXT: Carpal bossing is an osseous formation at the dorsal portion of the quadrangular joint, which rarely becomes symptomatic. However, in some patients it causes pain, restricted mobility and can lead to complications like tendon rupture, inflammatory and degenerative joint disease. AIM: In this article, we present our experiences with this rare disorder in order to improve diagnostic and therapeutic proceedings. SETTINGS DESIGN: This is a multicenter and interdisciplinary observation made by orthopaedic surgeons and radiologists in the years 2010 to 2015. Retrospective observational study. The follow up period was 2 years. MATERIALS AND METHODS: In the observed time period, eight patients were diagnosed with symptomatic carpal bossing. Symptoms were pain at palmar flexion and limited mobility of the wrist in combination with a palpable protuberance over the quadrangular joint. All patients underwent X-ray, CT and MRI examinations. A conservative treatment strategy was initiated for 6 weeks in all patients, followed by a wedge resection when symptoms were persisting and disabling. RESULTS: After the conservative treatment schedule, five patients were asymptomatic. Three patients had persisting pain and were thus recommended for surgery. In the postoperative course, two patients were asymptomatic. One patient developed a type 1 complex regional pain syndrome (CRPS) in the first postoperative year, which was successfully treated with pain-adapted physiotherapy, pharmacotherapy with analgesics and calcitonin, and a triple CT-guided thoracic sympathetic nerve blockade. CONCLUSION: Carpal bossing is a mostly asymptomatic entity, which in our experience gets symptomatic due to direct trauma or repetitive stress, especially in competitive racket sports players. It can be diagnosed by thorough clinical examination and multimodal diagnostic imaging. Conservative treatment comprises an excellent prognosis, however surgery, either wedge resection or arthrodesis, must be considered if the response is not positive after 6 weeks.