Sonography of the hand and wrist.

Teefey SA, Middleton WD, Boyer MI. Semin Ultrasound CT MR 2000 Jun;21(3):192-204.

Not only is the anatomy of the hand and wrist complex, but also its pathologic conditions are quite diverse. Although plain radiographs, CT, arthrography, and MRI have traditionally been used to evaluate the hand and wrist, ultrasound is beginning to take its place alongside these more traditional imaging modalities and is being ordered with increasing frequency by orthopedic surgeons. This article reviews the pertinent gross anatomy and sonographic technique used to scan the hand and wrist and also describes the sonographic findings associated with the most common hand and wrist pathologic conditions. These include soft tissue tumors, tenosynovitis, tendinous and ligamentous injuries of the hand, Dupuytren’s contracture, foreign bodies, and carpal tunnel syndrome (CTS).

Rupture of the extensor pollicis longus tendon.

Bonatz E, Kramer TD, Masear VR. Am J Orthop 1996 Feb;25(2):118-22.

Rupture of the extensor pollicis longus (EPL) tendon after nondisplaced fracture of the distal radius is a known complication, but can also occur in nonrheumatoid patients without a history of fracture. This study is a retrospective analysis of seven patients treated between 1985 and 1992. Five EPL ruptures occurred with nondisplaced Colles’ fractures. Two involved a chronic tenosynovitis of the second dorsal extensor compartment of the wrist. The age of the patients ranged from 29 years to 68 years (mean, 42 years). Length of follow-up ranged from 6 weeks to 62 months (mean, 30 months). Rupture occurred at a median of 7 weeks (range, 2 weeks to 11 months) from the time of the distal radius fracture. Three extensor indicis proprius tendons and four free palmaris longus tendon grafts were performed. At final follow-up, six patients had an extensor lag < 10 degrees or normal thumb interphalangeal joint motion. One patient had a 25 degrees extensor lag. The causes of EPL rupture include mechanical irritation, attrition, and vascular impairment leading to delayed rupture. Synovitis of the extensor carpi radialis due to repetitive use may invade the EPL tendon and lead to rupture. Extensor indicis proprius transfer or free palmaris longus grafts yield good results after EPL rupture.

Incidence and causes of tenosynovitis of the wrist extensors in long distance paddle canoeists.

du Toit P, Sole G, Bowerbank P, Noakes TD. Br J Sports Med 1999 Apr;33(2):105-9.

OBJECTIVES.
To investigate the incidence and causes of acute tenosynovitis of the forearm of long distance canoeists.

METHOD.
A systematic sample of canoeists competing in four canoe marathons were interviewed. The interview included questions about the presence and severity of pain in the forearm and average training distances. Features of the paddles and canoes were determined.

RESULTS.
An average of 23% of the competitors in each race developed this condition. The incidence was significantly higher in the dominant than the nondominant hand but was unrelated to the type of canoe and the angle of the paddle blades. Canoeists who covered more than 100 km a week for eight weeks preceding the race had a significantly lower incidence of tenosynovitis than those who trained less. Environmental conditions during racing, including fast flowing water, high winds, and choppy waters, and the paddling techniques, especially hyperextension of the wrist during the pushing phase of the stroke, were both related to the incidence of tenosynovitis.

CONCLUSION.
Tenosynovitis is a common injury in long distance canoeists. The study suggests that development of tenosynovitis is not related to the equipment used, but is probably caused by difficult paddling conditions, in particular uneven surface conditions, which may cause an altered paddling style. However, a number of factors can affect canoeing style. Level of fitness and the ability to balance even a less stable canoe, thereby maintaining optimum paddling style without repeated eccentric loading of the forearm tendons to limit hyperextension of the wrist, would seem to be important