Clinical examination, dorsoplantar radiographs and transverse sonographic scans of the plantar region of the forefoot were performed on 35 healthy individuals as well as 25 patients with inflammatory joint disease and forefoot symptoms. The ultrasound revealed twenty plantar flexor tenosynovitides in 12 of the 25 patients. In 14 out of the 20 tenosynovitides there was no metatarsophalangeal effusion in the same digit. Thus, also plantar tenosynovitis and not only metatarsophalangeal arthritis can promote symptoms of the forefoot. Only in eight of the 20 tenosynovitides the clinical examination was positive. Ultrasound is a more objective procedure than clinical examination in diagnosing plantar tenosynovitis. This finding has not only a diagnostic but also a therapeutic implication.