Radiographs Wrist

Radiographic changes lypical of rheumatoid arthritis on posteroanterior hand and wrist x-rays, which must include erosions or unequivocal bony decalcification localized to or most marked adjacent to tire involved joints (osteoarthritis changes alone do not qualify). 

FIGURE 16.6 Radiograph of the joint angle transducer (IJAT) implanted in the wrist. The magnet is implanted in the lunate bone (top) while the magnetic sensor array is implanted in the radius. Leads going to the implant case can be seen as well as intramuscular and epimysial electrodes with their individual lead wires. 

Fig. 2 27a-e. Scaphoid bone, a PA scaphoid with ulna deviation, b Lateral wrist, c 45° Oblique scaphoid with ulna deviation, d 35°angled PA scaphoid view with ulna deviation, e Resultant Radiographs... 

Fig. 4.8. Plain radiograph of the wrist demonstrates thep-eriosteal reaction initially detected on ultrasound...

Inclusion of the wrist and elbow in radiographs of forearm fractures is mandatory to exclude associated injuries to these joints (see Monteggia/Galeazzi). One pitfall in interpreting forearm radiographs is to misdiagnose the nutrient artery as an undisplaced fracture. This vessel maybe visualised on the AP radiograph at the junction of the proximal and middle third of the radius. It has a distal entrance point and runs obliquely in a proximal direction. 

Clinical examination reveals a laterally swollen elbow, tender at the fracture site, which is increased by active flexion of the wrist. Interpretation of the AP and lateral radiographs depend on the degree of ossification of the capitellum and the extent of the displacement. The lesser the degree of ossification, the harder it is to assess the fidl extent of the injury. In infants, where there is no ossification of the distal humeral epiphysis, lateral condylar injury may be confused with physeal separation or dislocation of the joint Physeal separation is the conunonest of these injuries in infants less than 1 year old. Often the only sign of injury is a small sliver of displaced metaphyseal bone. 

In addition to AP and lateral radiographs, the child may complain of referred pain in the wrist and increased tenderness on forearm supination/prona-tion. 

The scaphoid is the most common site of occult fractures in the wrist area, with up to 20-25% of cases unnoticed at the initial evaluation (Waizenegger et al. 1994). When the diagnosis is delayed, scaphoid fi actures have high rates of complications such as pseudoarthrosis, avascular necrosis of the proximal pole of the bone and secondary radiocarpal osteoarthritis with chronic pain and impaired function. A variety of diagnostic modalities, such as additional radiographic views, bone scan, CT and MR imaging, have been advocated for early detection of scaphoid fractures. The choice between an addi-... 

Fig. 10.80 a-c. Scaphoid fracture, a Coronal 12-5 MHz US image over the lateral aspect of the wrist with corresponding b diagram and c anteroposterior radiographic correlation displays a fracture of the waist of the scaphoid as a step-off deformity of the hyperechoic cortical line (open arrow). Note a perilesional hypoechoic halo (arrowheads) surrounding the fracture site, consistent with a local hematoma. Rad, radius... 

The diagnosis of dislocation of carpal bones may be challenging on plain films. Dislocations affect mostly the lunate which, being free from tendon attachments, is prone to volar dislocation, a condition commonly referred to as perilunate dorsal dislocation of the wrist. Even if radiographic examination can recognize the displacement of the lunate, in some cases this condition goes unnoticed at the first examination and US can be required to assess... 

Lee D, van Holsbeeck MT, Janevski PK et al (1999) Diagnosis of carpal tunnel syndrome. Ultrasound versus electromyography. Radiol Clin North Am 37 859-872 Lee JC, Healy JC (2005) Normal sonographic anatomy of the wrist and hand. RadioGraphics 25 1577-1590 Leslie BM, Ericson WB Jr, Morehead JR (1990) Incidence of a septum within the first dorsal compartment of the wrist. J Hand Surg [Am] 15 88-91... 

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