Surgical Anatomy of the Radial Nerve at the Elbow and in the Forearm: Anatomical Basis for Intraplexus Nerve Transfer to Reconstruct Thumb and Finger Extension in C7 − T1 Brachial Plexus Palsy

Abstract

C7 - T1 palsy results in complete loss of finger motion and poses a surgical challenge. This study investigated the anatomy of the radial nerve in the elbow and forearm and the feasibility of intraplexus nerve transfer to restore thumb and finger extension. The radial nerves were dissected in 28 formalin-fixed upper extremities. Branching pattern, length, diameter, and number of myelinated fibers were recorded. Commonly, the branching pattern (from proximal to distal) was to the brachioradialis, extensor carpi radialis longus, superficial sensory proximal to the lateral epicondyle, extensor carpi radialis brevis, supinator, extensor digitorum communis, extensor digiti minimi, extensor carpi ulnaris, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, and extensor indicis distal to the lateral epicondyle. Branches to the brachioradialis, extensor carpi radialis longus, and supinator can be transferred to the posterior interosseous nerve to restore hand movement in patients with C7 - T1 brachial plexus palsies; the supinator branch is probably the best choice in this regard.

BRACHIAL PLEXUS IN THE Leopardus geoffroyi

“…Often these movements are made naturally by L. geoffroyi in its habitat. Mammals of other orders which have a brachial plexuses formed by at least five ventral branches include the monotremes (16) , Myocastor coypus (17) , Bradypus variegatus (18) , Bradypus torquatus (19) , Hydrochaeris hydrochaeris (20) , Agouti paca (21) , Tamandua tetradactyla (22) , Myrmecophaga tridactyla (23) , Sus scrofa (24) and human (25) and non-human primates (26,27,28,29) . According to the study by Allam et al (30) , a plexus formed by four ventral branches is characteristic of those species whose thoracic limbs are limited to supporting body weight and to specialised cursorial locomotion, and which are constitutively deprived of an ossified clavicle, such as, for example, canids and ungulates.…”

Origin and antimeric distribution of brachial plexus nerves inAlouatta guariba clamitansCabrera, 1940 (Primates: Atelidae)

“…The participation of C4 in the formation of brachial plexus, observed in one specimen of A. g. clamitans, has been reported in human beings (Johnson et al 2010;Zhang et al 2016) and in non-human primates such as L. lagothricha (Robertson 1944), C. apella (Ribeiro et al 2005), S. sciureus (Araújo et al 2012) and M. mulatta (Santos-Sousa et al 2016), which characterises a pre-fixed brachial plexus (Parada et al 1989).…”

“…Among the 10 dissected plexuses, all presented their origin in the ventral branches of C5 to T1, although in one animal there was a delicate contribution of C4, and in another one there was a delicate contribution of T2. The origin of the plexus between C5 and T1 is very nearly a rule for primates, having been reported in G. senegalensis (Kanagasuntheram & Mahran 1960), S. sciureus (Mizuno 1969), P. ursinus (Booth et al 1997 (Lu et al 2013;Santos-Sousa et al 2016) and human beings (Parada et al 1989;Zhang et al 2016). However, intraspecific variations concerning the spinal segments of origin are also reported in those studies that used more specimens, as in the case of C. apella (Ribeiro et al 2005) and M. mulatta (Santos-Sousa et al 2016).…”

Inervación del Músculo Braquiorradial en Individuos Brasileños: Aspectos Anatomo-clínicos de la Biometría de Origen y Distribución Nerviosa

“…Por otro lado, nuestros resultados se aproximan a los vistos por Liu et al (1997), que en su muestra de 10 miembros superiores, el promedio de RP fue de 1,2 (DS 0,42), mientras que el promedio de PM fue 2,4 (DS 0,70). El promedio de 1,5 RP de nuestro estudio concuerda con Zhang et al (2016), que en 28 muestras obtuvieron un promedio de 1,5. El primer RP se ubicó a 3,13 cm (DS 1,12) proximal al EL.…”