Electromyographic analysis of brachioradialis to flexor pollicis longus tendon transfer in quadriplegia.

Electromyography was done in patients at the C6 level of quadriplegia after transfer of the brachioradialis to the flexor pollicis longus to restore lateral pinch and transfer of the posterior deltoid to the triceps to restore elbow extension. The relationship of the integrated electromyogram to pinch force during a graduated isometric contraction enabled characterization of the motor recruitment pattern. After tendon transfer, the pattern of the electromyographic response for the brachioradialis was the same as in the flexor pollicis longus in normal subjects, and the posterior deltoid after transfer to the triceps fired synergistically with the brachioradialis. These findings indicate reeducation of transferred muscles occurred after surgery and that they functioned as active primary motors.

Prospective study of sequential technetium-99m phosphate and gallium imaging in painful hip prostheses (comparison of diagnostic modalities).

Twenty-two painful hip prostheses were studied prospectively with plain radiography, aspiration and arthrography, Tc-99m phosphate bone imaging, and gallium imaging to evaluate loosening, infection, or both and to compare the accuracy of these modalities. Fifteen prostheses were revised yielding 14 loose femoral and eight loose acetabular components. Five proved to have infected prostheses. Arthrograms, plain radiographs, and bone scans are highly sensitive in detecting loosening of the femoral component. This study confirmed a previous retrospective study in demonstrating that accuracy of diagnosis of an abnormal acetabular component using all four modalities is less than that for the femoral component. In infected prostheses, phosphate bone imaging showed high sensitivity of a pattern that accurately diagnosed all the infected cases, whereas gallium imaging missed one case.