The lateral root of the ulnar nerve

In 158 brachial plexuses the origin of the fibers of the ulnar nerve-whether only from the medial or also from the lateral fascicle-was investigated. A lateral root was found in 56%. This lateral root may either be accompanied by fibers of the median nerve (type 1) or may run separately (type 2). Where this root crosses the medial root of the median nerve, either a small minority of fibers of the latter nerve may run behind the ulnar fibers (type a), or all median fibers are in front of them (type b). Considering the relation 56:44% between ulnar nerves with and without a lateral root both possibilities have to be considered as normal variations, none as a variety. In analogy to the term 'median loop' the term 'ulnaris loop' is suggested for specimens with a lateral root.     

Island flap supplied by the dorsal branch of the ulnar artery

Two cases are reported in which a fasciocutaneous island flap was employed supplied by the ulnaris dorsalis artery after the method proposed by Becker and Gilbert. The original technique has been modified by the authors, and this produces a better venous outflow. The vascular pedicle includes, besides the ascending branch of the artery and the venae comitantes, one of the superficial veins together with its respective subdermal band. A technique is also described that provides an optimal length for the vascular pedicle.     

Recurrent anterior dislocation of the ulnar nerve at the cubital tunnel

Recurrent anterior dislocation of the ulnar nerve at the cubital tunnel is reported in two patients. This was due to traumatic attenuation of the flexor carpi ulnaris retinaculum. The mechanism of injury in both patients was a fall with the shoulder abducted and the elbow acutely flexed. Both patients had relief of their neurologic symptoms following anterior submuscular transposition of the ulnar nerve.     

Parameters of the ulnar medullary canal for locked intramedullary nailing

The development of a ‘one shot’ locked intramedullary device for rapid stabilization of adult ulnar fractures would benefit surgeon and patient alike, but, before a prototype device can be manufactured, basic internal measurements of the ulnar medullary canal are needed. Various sections and measurements of 142 adult human cadaver ulnas were performed to determine the calibre, length and curvature of the medullary canal. These measurements revealed that the device can be of one calibre but will need to be manufactured in three different lengths. Because of the minimal curvature of the ulnar medullary canal and the ability to lock the nail both proximally and distally, the nail can be straight and inserted loosely. A prototype design is described.     

A surgical approach to the motor branch of the ulnar nerve

Isolated injury to the motor branch of the ulnar nerve is a relatively rare injury, often initially misdiagnosed. If repair is attempted through the original laceration without complete motor branch exposure, results can be less than satisfactory. A recent case illustrates this injury and provides us with an opportunity to review the surgical anatomy of the motor branch of the ulnar nerve. The surgical approach to the motor branch has been detailed and specifically emphasizes complete motor branch exposure from the main ulnar nerve trunk to the most distal motor branch entry into the adductor pollicis muscle. This approach permits definition of the exact level of the nerve injury, preservation of any intact proximal fine motor branches, and facilitates the mechanics of nerve repair.     

Functional hemitongue reconstruction with the microvascular ulnar forearm flap.

Thirteen patients with squamous cell carcinoma of the tongue underwent full-thickness longitudinal resection of the hemitongue and immediate microvascular reconstruction using a large, contoured ulnar forearm flap. Six of the 13 patients had a composite resection for which an additional vascularized iliac crest graft was used to reconstruct the mandible and to provide support to the overlying contoured flap. To increase tongue mobility, the skin flap was designed for independent reconstruction of the hemitongue and the floor of mouth. Twelve patients were evaluated for swallowing and speech, including dietary assessment, cineradiography, and voice spectrographic analysis. Contrast cineradiography was performed to determine oral tongue mobility during the first phase of swallow. Nine patients with a narrow reconstructed tongue root and a large surface area in the floor of the mouth had good tongue mobility, allowing them to transfer food dynamically from the mouth into the pharynx for swallowing. The remaining three patients, who had a wide tongue root and an ill-defined floor of the mouth, had decreased tongue mobility and poor oral transport. The functional outcome of swallowing and speech strongly correlated with the shape of the root of the tongue, the proximity of the reconstructed tongue to the palate, and the surface area of the floor of the mouth.     

Hypertrophy of radial and ulnar arteries following denervation of the chicken wing

Summary Denervation of radial and ulnar arteries in the growing and adult domestic fowl was achieved by unilateral sectioning of the brachial plexus. Eight weeks later the denervated arteries and those of the contralateral wing were examined with light- and electron microscopy to determine the effect of denervation on arterial structure.In growing fowls, the area of the media in radial and ulnar arteries was increased by 29% and 25%, respectively, after denervation. The number of smooth muscle layers was also significantly increased by 16% (radial) and 14% (ulnar), but no significant variation was seen in the wall/lumen ratio of either growing artery. In adult fowls, the area of the media was increased by 93% (radial) and 32% (ulnar) following denervation and the number of smooth muscle cell layers increased by 39% (radial) and 11% (ulnar). There was also an increased wall/lumen ratio of 64% (radial) and 92% (ulnar).These results indicate that hyperplasia of smooth muscle has occurred in response to denervation. Flow-cytometric DNA analysis of growing arteries also indicates that the increase in muscle-cell volume is a result of cell division (not polyploidy) since no significant differences were found between the control and denervated arteries in any stages of the cell cycle.