[Transfer of the pronator quadratus to restore opposition of the thumb: An anatomic study and a clinical report]. / Étude anatomique sur le lambeau de carré pronateur pédiculé réinnervé pour réanimer l'opposition du pouce et application clinique.

OBJECTIVE: The purpose of this study is to explore the feasibility of reconstructing the APB with a pedicled PQ flap, and to report results in a child presenting with bilateral radial deficiency. METHODS: Twenty-one injected cadaver upper extremities were dissected. The muscle was pedicled distally on the transverse carpal artery, and reinnervated with the flexor digiti minimi (FDM) motor branch. The transfer was evaluated on 3 parameters: surgical feasibility, length of the distal pedicle and distance from the coaptation site to the muscle entry of recipient nerve. A bilateral PQ pedicled transfer was accomplished in a 17-month old child with bilateral radial deficiency. RESULTS: In the cadaver study, transfer of PQ to the APB was feasible and the distal end of the PQ transfer was reaching the radial side of the first metacarpophalangeal joint in all cases. The length of the distal pedicle on the transverse carpal artery was 38.5±0.20mm. The distance from coaptation of the FDM to the PQ muscle entry was 43.0±3.77mm. At 7 months, there was a cosmetic improvement of the thenar eminence, a bilateral M3 abduction of the thumb and a functional improvement from bilateral PQ pedicled transfer. CONCLUSIONS: Reconstruction of the APB may be achieved with a PQ pedicled transfer reinnervated, improving the function and the cosmetic aspect of the thenar eminence without sacrificing any function of the hand.

Rehabilitation of distal radioulnar joint instability.

Distal radioulnar joint (DRUJ) instabilities are common and often combined with other injuries of the interosseous membrane and/or the proximal radioulnar joint. Once they are diagnosed and the treatment is chosen, physiotherapists have limited choices due to the lack of validated protocols. The benefits of proprioception and neuromuscular rehabilitation have been brought to light for the shoulder, knee and ankle joints, among others. However, no program has been described for the DRUJ. The purpose of this article is to study the muscular elements responsible for active DRUJ stability, and to propose a proprioceptive rehabilitation program suited to this condition.

Selective anterior interosseous nerve conduction study: Coaxial needle versus surface electrode recordings.

OBJECTIVES: The aim is to determine which method provides the most selective motor nerve conduction of the anterior interosseous nerve (AIN), when the stimulation cannot be restricted to this nerve. METHODS: The AIN was stimulated at the elbow, along with the whole median nerve. The motor action potential (MAP) of the AIN was recorded with 2 different methods: 1 - a coaxial needle inserted in the pronator quadratus muscle (PQ); 2 - a pair of surface electrodes fixed on the PQ. Twenty-two controls and 4 patients with AIN palsy were studied with both methods. Two among the patients were also examined with a 3rd method involving a pair of surface electrodes fixed on the flexor pollicis longus. RESULTS: For controls, with needle recording, distal motor latency (DML) to the PQ was 4.2ms and PQ MAP amplitude was 15.0mV. With surface recording, distal motor latency (DML) to the PQ was 3.1ms and PQ compound MAP (CMAP) amplitude was 5.1mV. For patients, with needle recording, DML was normal, and MAP amplitude was drastically decreased as compared with controls, while with surface recording, DML and CMAP amplitude showed no substantial change. DISCUSSION AND CONCLUSIONS: These results demonstrate that recording with a coaxial needle electrode inserted in the PQ is the only method to provide a specific NCS of the AIN, and permit the diagnosis of isolated AIN lesions, which could otherwise be missed.