OBJECTIVE To assess the current role of ultrasound in the diagnosis and treatment of pathological changes in the wrist and hand. METHODS 39 patients (14 male and 25 female, mean age 35 yrs.) with ill-defined pain and/or swelling of the wrist or hand were examined using a high-definition ultrasound (US) instrument. RESULTS 18 patients had tenosynovitis, which in one patient was due to a previously unsuspected foreign body. 10 patients had arthritis involving the wrist and 5 the fingers; 2 patients had a ganglion; one had a neuroma of the median nerve and one patient with a previous tenorrhaphy suffered from the recurrent rupture of this tendon. Two patients had carpal tunnel syndrome, one due to tenosynovitis and one due to the formation of a post-operative fibrotic sheath around the median nerve. 7 patients with synovitis of the wrist underwent US-guided synovial biopsy. 12 patients with tenosynovitis and 6 with arthritis received injections of corticosteroids plus anaesthetic under US-guidance. The spreading of the steroid crystals around the tendon and throughout the joint could be easily monitored. No complications were encountered. CONCLUSIONS High-definition ultrasound is a valuable technique for the imaging of pathologic changes of the wrist and hand and for injection therapy.