Clinical injuries of the carpal scaphoid are frequently seen at accident and emergency departments. Some exhibit delayed radiographic visualization of a fracture. The radioisotope bone scan is a sensitive test and increased uptake is observed in healing fractures. Twenty-three patients with an initial diagnosis of clinical fractures of the scaphoid were studied clinically, radiologically and independently by 99Tcm-MDP isotope scans. Three-quarters of the patients required only 1 month's management. Their corresponding bone scans were normal or not suggestive of a fracture. The remaining 25 per cent, who clinically required a more prolonged treatment (greater than or equal to 5 weeks' immobilization), were noted independently to have positive scans whether a fracture was observed or not. It is concluded that there is a stronger correlation between clinical examination and a bone scan than with a standard radiographic examination. It is proposed that patients still tender at 3 weeks should have a carpal isotope bone scan to identify if there is an important wrist injury and appropriate treatment commenced.