Radiological Diagnosis

De Quervia'n Disease

Discussion

The T1 and T2 weighted MR images show abnormally thickened tendons of the extensor pollicis brevis and abductor pollicis longus [Figure - 1],[Figure - 2]. In addition the T2 weighted images reveal thin rim of fluid surrounding these thickened tendons [Figure - 2]. These two tendons also show abnormal signal especially on the T1 weighted images (appearing isointense to muscle rather than hypointense).

Tenosynovitis of the first extensor compartment of the wrist comprises De Quervains disease. Named after the Swiss surgeon who first described the syndrome in 1885, it can be considered a work related disease. It is frequently associated with jobs that require repetitive movements of the hands like typing and computer work. The inflammation affects the synovial sheaths of the tendons of the abductor pollicis longus and extensor pollicis brevis muscles. The patient presents with pain, swelling of the sheath and functional impairment. Clinically, the diagnosis is confirmed by the Finkelstein's test [1]. This test is performed in the following manner: The thumb is placed within the closed fist. Ulnar deviation of the wrist will elicit pain on the lateral aspect of the wrist. The diagnosis is almost always made clinically. Imaging is asked for only in case of equivocal clinical findings and hence has a limited role. High frequency ultrasound will show the thickened synovium, fluid within the tendon sheath and degenerative changes in the tendon itself [1]. On MR imaging, thickening of the tendons and an increased signal on T1 weighted and proton density weighted images characterize tendonitis. Tenosynovitis is suggested when there is fluid surrounding the tendon within the tendon sheath [2]. In a review of 5 cases, Glajchen et al concluded that increased thickness of the two tendons was the most reliable finding on MRI [3]. In another study by Chian et al focal radial styloid abnormalities were reported on plain X-ray in De Quervains disease including cortical erosions, sclerosis and periosteal bone apposition [4].

In the acute phase, multiple injections of steroids and local anesthetic agents into the tendon sheath will relieve the symptoms and may cure the condition. In chronic cases, local fibrosis compromises the abduction of the thumb. Trigger thumb (loss of gradual movements of abduction) is a sequel of such fibrosis. In these situations surgical release of the tendons may be required.