Idiopathic Proximal Radioulnar Synostosis – A Rare Case Report and Review of Literature

INTRODUCTION: Radioulnar synostosis is a bony connection between the radius and ulna, which causes restriction of the active and passive rotational movements of the forearm such as supination and pronation, which can lead to significant functional disability in the patients. CASE REPORT: A 35-year-old male carpenter presented with the complaint of right forearm supination and pronation restriction for the past 8 months with minimal pain at the elbow region with no previous history of trauma or surgery. On examination, forearm supination and pronation movements were completely restricted with normal elbow flexion and extension and with no neurovascular deficit. X-ray of the right radius ulna with elbow revealed synostosis between proximal radius and ulna at the level of the radial tuberosity. Synostosis was removed using both anterior and posterior approaches. Postoperatively patient is having good supination and pronation movements, no pain, and difficulty in his occupation. CONCLUSION: Idiopathic proximal radioulnar synostosis should be suspected in patients having restricted rotatory movements of forearm with no previous history of trauma or surgery and this is the first reported case of idiopathic proximal radioulnar synostosis. Complete resection of the synostosis with early initiation of aggressive physiotherapy helps in getting good functional outcomes.