Histomorphometry of the ulnar nerve and of its branches (original) (raw)
Related papers
Journal of Neurosurgery, 2006
Object In neurotization procedures, donor nerves—either whole or in part—with relatively pure motor function can be carefully chosen to provide the optimal nearby motor input with as little donor site morbidity as possible. In this context, the ulnar nerve branches to the forearm muscles are relatively dispensable; however, quantitation of and landmarks for these branches are lacking in the literature. Methods The ulnar branches to the flexor carpi ulnaris (FCU) and flexor digitorum profundus (FDP) muscles in 20 upper extremities obtained in adult cadaveric specimens were dissected and quantified. In the forearm, a mean of four nerve branches led to the FCU and FDP muscles. A mean of 3.4 branches led to the FCU muscle; of these, one to three were medial branches and zero to two were lateral. Medial branches to the FCU muscle originated a mean of 2.7 cm inferior to the medial epicondyle. Lateral branches to the FCU muscle originated at a mean of 3.3 cm inferior to the medial epicondy...
Surgical and Radiologic Anatomy, 2005
The branching pattern of the ulnar nerve in the forearm is of great importance in anterior transposition of the ulnar nerve for decompression after neuropathy of cubital tunnel syndrom and malformations resulting from distal end fractures of the humerus. In this study, 37 formalin-fixed forearms were used to demonstrate the muscular branching patterns from the main ulnar nerve to the flexor carpi ulnaris muscle (FCU) and ulnar part of the flexor digitorum profundus muscle (FDP). Eight branching patterns were found and classified into four groups according to the number of the muscular branches leaving the main ulnar nerve. Two (Group I) and three (Group II) branches left the main ulnar nerve in 18 and 17 forearms respectively. The remaining two specimens had four (Group III) and five (Group IV) branches each. Usually one or two branches were associated with the innervation of the FCU. However, in 2 cases, three and in one, four branches to FCU were observed. The FDP received a single branch in all cases, except in four, all of which had two branches. In six forearms, a common trunk was observed arising from the ulnar nerve to supply the FCU and FDP. The distribution of the muscular branches to the revealed muscles was outlined in figures and the distance of the origin of these branches from the interepicondylar line was measured in millimeters. The first muscular branch leaving the main ulnar nerve was the FCU-branch in all specimens. The terminal muscular branch of the ulnar nerve to the forearm muscles arose at the proximal 1/3 of the forearm in all specimens. In 7 forearms, Martin-Gruber anastomosis in form of median to ulnar was observed.
Surgical and Radiologic Anatomy, 2005
The branching pattern of the ulnar nerve in the forearm is of great importance in anterior transposition of the ulnar nerve for decompression after neuropathy of cubital tunnel syndrom and malformations resulting from distal end fractures of the humerus. In this study, 37 formalin-fixed forearms were used to demonstrate the muscular branching patterns from the main ulnar nerve to the flexor carpi ulnaris muscle (FCU) and ulnar part of the flexor digitorum profundus muscle (FDP). Eight branching patterns were found and classified into four groups according to the number of the muscular branches leaving the main ulnar nerve. Two (Group I) and three (Group II) branches left the main ulnar nerve in 18 and 17 forearms respectively. The remaining two specimens had four (Group III) and five (Group IV) branches each. Usually one or two branches were associated with the innervation of the FCU. However, in 2 cases, three and in one, four branches to FCU were observed. The FDP received a single branch in all cases, except in four, all of which had two branches. In six forearms, a common trunk was observed arising from the ulnar nerve to supply the FCU and FDP. The distribution of the muscular branches to the revealed muscles was outlined in figures and the distance of the origin of these branches from the interepicondylar line was measured in millimeters. The first muscular branch leaving the main ulnar nerve was the FCU-branch in all specimens. The terminal muscular branch of the ulnar nerve to the forearm muscles arose at the proximal 1/3 of the forearm in all specimens. In 7 forearms, Martin-Gruber anastomosis in form of median to ulnar was observed.
A Cadaveric Study of Ulnar Nerve Innervation of the Medial Head of Triceps Brachii
Clinical Orthopaedics and Related Research, 2009
The presence of a separately innervated muscle unit of the triceps may have possible surgical importance and can be used for motor reconstructions. The ulnar nerve is closely situated to the triceps muscle and rarely examined above the elbow. The aim of this cadaveric study was to explore a possible contribution of the ulnar nerve to motor innervation of the medial head of the triceps. We dissected 18 limbs from axillae to midforearm. The path of the ulnar nerve was followed, and examination was conducted of attachments to the triceps. Gross photographs were taken and samples histologically stained. Seventeen limbs had ulnar nerve branches proximal to the epicondyles that inserted on the medial head. Eleven of these branches were from the ulnar nerve trunk. The other six were nerve branches from the ulnar collateral branch of the radial nerve. The ulnar nerve and the ulnar collateral branch of the radial nerve are previously unrecognized sources of innervation of the medial head of the triceps brachii. These motor branches must be carefully preserved during the medial surgical approach above the elbow. The ulnar innervated part of the medial head of the triceps muscle may be used like an independent motor unit.
Ulnar nerve innervation of the medial head of the triceps brachii muscle: A cadaveric study
Clinical Anatomy, 2013
Although the ulnar nerve is closely associated with the triceps brachii muscle, the literature does not normally describe it as supplying this muscle. However, recent research has examined the ulnar nerve in the upper arm and identified branches supplying the medial head of the triceps brachii muscle. This study aims to expand upon this research by describing the course and incidence of these branches in a larger sample size. We examined 50 specimens in 25 cadavers. Ulnar innervation of the medial head of the triceps brachii was identified in 14 specimens (28%). The mean distance of the ulnar nerve branch midpoint was 26% along a line between the surgical neck and an epicondyle line, with a range of 11-39%. Innervation of the triceps brachii muscle by the ulnar nerve has important clinical and surgical implications.
The Deep Fascia of the Forearm and the Ulnar Nerve: An Anatomical Study
Introduction A reoperation for a cubital tunnel syndrome is not uncommon. Patients often complain of sensorimotor symptoms in the ulnar nerve distribution after their primary surgery. The documented etiologies for such a phenomenon include a “new” kinking of the distal ulnar nerve and a “new” compression of the ulnar nerve by the fascial septum in between or tendinous bands over the muscles of the forearm. The deep fascial plane along which the ulnar nerve travels in the forearm has had scant attention. We present an anatomical study to provide a better understanding of such etiologies to aid physicians in performing successful primary ulnar nerve release that does not lead to risky reoperations and ultimately yields improved patient satisfaction. Materials and methods The forearms of 12 fresh frozen cadavers (24 arms) underwent dissection, during which the fascial relationships between the ulnar nerve and muscles of the anterior compartment were explored with a blunt technique. The relationship between the fascial planes and the ulnar nerve was quantitatively and qualitatively documented. The ranges of motion of the elbow were also observed for any potential compression points on the nerve during the movement. Results In all specimens (n = 24), the ulnar nerve entered the forearm between the humeral and ulnar heads of the flexor carpi ulnaris, after which it routed deep to a deep fascia between the anterior surface of the flexor carpi ulnaris and the posterior surface of the flexor digitorum superficialis. Ulnar nerve branches to the flexor carpi ulnaris pierced this fascial septum while en route to the posterior surface of the muscle. Medially, the branches to the flexor digitorum profundus also pierced this fascial plane. In most arms, the fascia became thinner near the junction between the proximal two-thirds and distal one-third of the forearm. On no side was the ulnar nerve found to be grossly compressed by this deep fascia. However, with the extension of the elbow, a degree of angulation of the proximal ulnar nerve was observed due to its compact connection with the deep fascia. Conclusion Our study revealed that there is an intimate relationship between the ulnar nerve and the deepfascia of the forearm. Since the ulnar branches to the overlying flexor carpi ulnaris pierce this deep structure, a care should be given to its anatomical course during surgery in this region to prevent denervation of the muscle.
Surgical and radiologic anatomy : SRA, 2015
Precise knowledge of motor nerve branches is critical to plan selective neurectomies for the treatment of spastic limbs. Our objective is to describe the muscular branching pattern of the ulnar nerve in the forearm and suggest an ideal surgical approach for selective neurectomy of the flexor carpi ulnaris. The ulnar nerve was dissected under loop magnification in 20 upper limbs of fresh frozen cadavers and its branches to the flexor carpi ulnaris muscle (FCU) and to the flexor digitorum profundus muscle (FDP) were quantified. We measured their diameter, length and distance between their origin and the medial epicondyle. The point where the ulnar artery joined the nerve was observed. The position in which the ulnar nerve gave off each branch was noted (ulnar, posterior or radial) and the Martin-Gruber connection, when present, had its origin observed and its diameter measured. The ulnar nerve gave off two to five muscular branches, among which, one to four to the FCU and one or two t...
Injury, 2019
Elbow flexion is the first goal in upper partial brachial plexus palsy treatment. However, elbow extension is essential for daily living activities. To recover this function, one fascicle of ulnar nerve can be transferred to the branch of the long head of the triceps, but this procedure has been previously published in only two patients. The goal of our study is to assess a larger series of transfers of one fascicle of ulnar nerve to the branch of the long head of the triceps to help patients recover elbow extension. Ten male patients with C5, C6 and C7 brachial plexus injuries underwent operation. For shoulder recovery, we transferred the spinal accessory nerve and rhomboid nerve. For elbow flexion, one fascicle of median nerve was transferred to the nerve of the biceps. For elbow extension, we transferred one fascicle of ulnar nerve to the branch of the long head of the triceps. Tendon transfers were performed for wrist and finger extension. Nine patients recovered M4 elbow flexion and extension. One patient had M3 elbow extension and flexion. Average active shoulder elevation was 85 °and average active shoulder external rotation was 65 °All patients recovered finger and wrist extension. The classical techniques of grafts or phrenic or intercostal nerve transfers to recover elbow extension are not always reliable, according to the literature. Because the harvested ulnar nerve motor fascicle is close to the branch of the long head of the triceps, the recovery time for this procedure is shorter than that of other described nerve transfers. The isolated recovery of the reinnervated long head of the triceps muscle excludes spontaneous recovery occasionally noted in upper root plexus injuries. The transfer of one fascicle of ulnar nerve to the branch of the long head of the triceps is reliable for active elbow extension recovery in C5, C6 and C7 brachial plexus palsies.
The Journal of hand surgery, 2015
To analyze the anatomical feasibility of transferring a motor branch nerve to the flexor carpi ulnaris (FCU) to the triceps upper medial head motor branch (UMHM) and to report the resultant outcome of the restoration of elbow extension in 5 patients with extensive brachial plexus injury. The ulnar and radial nerves were dissected in 10 cadavers. We measured the length and diameter of the branches to the FCU and the UMHM branch and counted the axons. Then, 5 male patients, mean age 30 years, underwent FCU nerve branch transfer for reconstruction of elbow extension. Elbow flexion was restored via a median nerve branch to biceps transfer. Mean UMHM nerve length and diameter were 86 and 1.5 mm, respectively. Mean number of branches to the FCU muscle was 2.9. Mean FCU nerve length and diameter were 50 and 1.0 mm, respectively. Mean number of myelinated fibers was 818 and 743 for the UMHM and the longest branch to the FCU, respectively. Coaptation between nerves was possible without tensi...