Intrinsic balancing in reconstruction of the tetraplegic hand.

This article reviews 183 hand reconstructions in 135 consecutive tetraplegic patients. Comparisons were made between 103 extrinsic reconstructions with intrinsic balancing procedures and 80 extrinsic reconstructions without intrinsic balancing procedures. Extrinsic reconstructions (tendon transfers and tenodesis in the forearm muscles) were augmented by intrinsic reconstructive procedures (tendon transfers or tenodesis to improve the intrinsic balance of the fingers) in patients exhibiting digital imbalance. Intrinsic procedures included primarily the flexor digitorum superficialis (FDS) lasso procedure or the intrinsic tenodesis procedure. The patients were stratified by level of spinal cord injury and by type of extrinsic and intrinsic reconstruction. Hands reconstructed with intrinsic balancing versus without intrinsic balancing, as well as intrinsic balancing using a FDS lasso procedure versus an intrinsic tenodesis procedure, were compared with patients with the same level of spinal cord function. Patients who underwent reconstructions with intrinsic balancing had more grip strength, by an average of 13-26 N, than those who did not undergo intrinsic balancing. When different intrinsic procedures were compared, there was improvement in grip strength and function in activities of daily living for all hands, but there was no significant difference between FDS lasso or intrinsic tenodesis procedures. The indications for intrinsic balancing during extrinsic reconstruction are developed into treatment algorithms based on the senior author's surgical experience. The authors recommended that digital intrinsic procedures be included in hand reconstruction for tetraplegic patients exhibiting intrinsic imbalance to help improve digital function and provide increased grip strength.

Arborization of the distal posterior interosseous nerve.

The distal posterior interosseous nerve was dissected in 41 cadaveric specimens. Intraarticular branches were tagged with radioopaque markers and verified by fluoroscopy. The nerve averaged 1.3 mm in diameter and was located on the radial side of the fourth dorsal compartment encased in thickened fascia. Six of the specimens had a branch to the distal radioulnar joint, which originated 5 cm proximal to the joint. Distally, the nerve coursed with terminal branches of the interosseous artery. Innervations were categorized according to level: radiocarpal, midcarpal, and terminal. Fourteen had innervations to all three levels, and there were radiocarpal branches in 27 specimens, midcarpal branches in 35, and terminal branches in 29. Varying combinations of innervations were seen.

Quantifying bone loss from the proximal femur after total hip arthroplasty.

To define the natural history of bone loss around a femoral prosthesis, the bone mineral content and bone mineral density were measured for each femur in 28 patients with unilateral total hip arthroplasty, 18 age-matched controls, and seven patients with unilateral osteoarthritis. The areas measured were inside the lesser trochanter and 4.8 cm distal to it. The contralateral hip served as the control. Three years after arthroplasty there was 40% loss in average bone mineral content inside the lesser trochanter, and 28% loss in average bone mineral content 4.8 cm distally in the medial cortex. At seven to 14 years after operation, patients had lost 40% of bone proximally and 49% distally. The data suggest that this may progress in a proximal-to-distal fashion, and could account for a 50% decrease in bone mass seven to 14 years after surgery.

Broadband ultrasound attenuation of the calcaneus predicts lumbar and femoral neck density in Caucasian women: a preliminary study.

Recent studies have demonstrated the ability of ultrasound techniques to differentiate normal and osteoporotic women. To define the ability of broadband ultrasound attenuation (BUA) of the calcaneus to predict axial bone mass, the ultrasound value was correlated with lumbar vertebral and femoral neck density in 22 Caucasian women. The three measures of bone mass inversely correlated with age: lumbar density (r = 0.54), femoral neck density (r = 0.65), and BUA (r = 0.73). BUA correlated with lumbar (r = 0.83) and femoral neck (r = 0.87) density. Lumbar vertebral density predicted femoral neck density with a standard error of estimate (SEE) of 0.07 g/cm2, and femoral neck density predicted lumbar density with a SEE of 0.09 g/cm2. BUA of the calcaneus was as effective as either axial bone mass measure in predicting the other value: the SEE for lumbar density was 0.09 g/cm2 while that for femoral neck density was only 0.06 g/cm2. The results of this preliminary study indicate that this rapid, radiation-free technique can accurately predict axial bone mass, and may be of value as an initial procedure to discriminate those women warranting more extensive radiologic evaluations.