UNASSIGNED: The ulnar\'s nerve compression at the Guyon\'s canal is not a frequent entity add to it that vascular lesions are rarely involved as a causative agent of this syndrome.
METHODS: We report a case of a young male patient admitted in our department for a Guyon\'s canal syndrome due to an aneurysm of the ulnar artery and underwent a surgical decompression. Post-operative course was uneventful and the patient was satisfied with the result.
UNASSIGNED: Many etiologies are involved in the Guyon\'s canal syndrome and these etiologies can be arranged into groups. Previous treatment attempts, the duration and severity of the symptoms and the underlying etiology dictate the treatment options. Adjacent vascular enlargement is not a usual cause of Guyon\'s canal compression and a few case reports were reported in the literature. Surgical treatment by opening and releasing the roof of Guyon\'s canal and removing the aneurysm helped to achieve good outcome in most reports.
CONCLUSIONS: Guyon\'s canal syndrome is less frequent than both cubital tunnel syndrome or carpal tunnel syndrome and many causative agents have been described. Vascular lesions are not the usual cause of compressing the ulnar nerve at the wrist and through this case we spotlighted this entity as another possible etiology requiring an adequate treatment for a better outcome.

Isolated injury to the deep motor branch of the ulnar nerve caused by stabbing is sporadic, with only one reported case in the English-language literature. We report one such case treated successfully using nerve grafting. A 33-year-old patient had sustained a stab wound to the right hypothenar eminence and showed a claw hand deformity. Needle electromyography study revealed denervation potentials with no voluntary motor unit action potentials (MUAPs) in the first dorsal interosseous (FDI) muscles. Nerve exploration revealed a neuroma-in-continuity in the intrinsic motor branch of the ulnar nerve. Intraoperative nerve stimulation confirmed the absence of compound muscle action potentials in the FDI. The damaged scarred nerve was resected, and the 15-mm defects were reconstructed with cable autografting. Two years and 5 months after the surgery, voluntary MUAPs were observed in the FDI. The pinch strengths recovered. Laceration of the deep branch of the ulnar nerve caused by stabbing can sometimes remain hidden as the hand sensation remains intact. Pre- and intraoperative electrophysiological examination is essential to assess the severity of the injured nerve and determine an appropriate surgical option. Even nerve grafting can facilitate satisfactory results as target intrinsic muscles are quite close to the repair site.

BACKGROUND: Ulnar tunnel syndrome (UTS) is relatively uncommon compared to the carpal tunnel or cubital tunnel syndromes. Few reports dedicated to the functional outcomes after surgical intervention of the UTS exist. Herein we compare the outcomes of patients with UTS of different etiologies.
METHODS: Patients diagnosed with UTS between 2016 and 2020 were recruited. Ulnar tunnel release was performed in all patients, along with other necessary osteosynthesis or reconstructive procedures in the traumatic group. Patients were followed-up every six months post-operatively. Outcomes measured include: objective evaluations, subjective questionnaires, records of clinical signs, and grading of the British Medical Research Council scale for intrinsic muscle strength.
RESULTS: 21 patients were recruited, and favorable results were noted in all of them after surgery. Traumatic UTS patients had a worse initial presentation than the non-traumatic cases, but had a greater improvement after surgery and yielded outcomes comparable with those of the patients without trauma. Patients with aberrant muscles in their wrists had better outcomes in some objective measurements than those without aberrant muscles.
CONCLUSIONS: Ulnar tunnel release improves the outcome of patients regardless of the etiology, especially in patients with trauma-induced UTS. Thus, a proper diagnosis of the UTS should be alerted in all patients encountering paresthesia in the ulnar digits, ulnar-sided pain, weakness of grip strength, or intrinsic weakness to ensure good outcomes.

OBJECTIVE: Several studies have been conducted on the variations and branching pattern of the ulnar nerve in the hand. There are few studies conducted on defining the distance of ulnar nerve from bony landmarks in the palm. Ulnar nerve is closely related to the pisiform and hook of hamate which act as important landmarks.
METHODS: The study was conducted on 30 formalin fixed adult hand specimens in the department of Anatomy. Various measurements related to the ulnar nerve in the palm were taken using a divider and Vernier Calipers and the values were tabulated after obtaining the mean and standard deviation.
RESULTS: The average distance seen in the hand specimens [n = 30] from pisiform to the division of ulnar nerve into superficial and deep branch was 0.89 ± 0.25cm and the distance between pisiform bone up to the division of superficial branch of ulnar nerve into proper and common digital branches was 1.36 ± 0.59 cm. The average distance from the origin of proper digital branch of ulnar nerve to the head of fifth metacarpal bone was 5.25 ± 0.59 cm. The length of common digital branch of ulnar nerve from its origin to division into 2 sensory branches was 4.31 ± 1.09 cm.
CONCLUSIONS: This study provides the metric parameters of the ulnar nerve in the hand from its significant bony landmarks which should be kept in mind during surgical procedures to minimize the incidence of injury to its branches. It would assist the orthopedic surgeon in the treatment of ulnar nerve compression in the Guyon\'s canal.

Upper extremity nerve injuries in cyclists include carpal tunnel syndrome and ulnar neuropathy at the wrist. Electromyography and nerve conduction studies aid in the diagnosis of neuropathies. Diagnostic ultrasonography or MRI can also be helpful for evaluation. Overuse injuries in the upper extremity includes biker\'s elbow, or a tendinopathy of the common flexor or extensor tendons, which is more common in mountain biking. Neck pain is also a common issue for cyclists. Treatment of these conditions varies from conservative management to surgical options, but a bicycle fit assessment is recommended for any ongoing symptoms.

The ulnar nerve can be subject to numerous types of compression. The most common are cubital tunnel and ulnar tunnel syndromes, but there are many others with more uncommon etiologies. The existence of additional communicating branches, median nerve involvement, various types of injuries, and unusual anatomical variations can be a challenge for both diagnosis and treatment. This review presents a comprehensive depiction of ulnar nerve entrapment syndromes with particular reference to their anatomical background, risk factors, and clinical evaluation. Even common disorders can result from atypical morphological changes. It is important to be familiar with them as it is a key ability in daily medical practice.

Carpal tunnel syndrome is median nerve symptomatic compression at the level of the wrist, characterized by increased pressure within the carpal tunnel and decreased nerve function at the level. Carpal tunnel release decreases pressure in Guyon\'s canal, via open techniques, with symptom and two-point discrimination improvement in the ulnar nerve distribution. We hypothesize that endoscopic carpal tunnel release improves two-point discrimination in the ulnar nerve distribution as well. This study includes 143 patients who underwent endoscopic carpal tunnel release between April 2016 to June 2019 in a single, community-based teaching hospital. A comprehensive retrospective chart review was performed on patient demographics, pre- and post-operative two-point discrimination test results, and complications. The effects of sex, age, and diabetes mellitus in the ulnar and median nerve territories with two-point discrimination tests were analyzed. As well as the differences in two-point discrimination among patient\'s based on their smoking status. There were significant post operative improvements in both the median (7.7 vs 4.4 mm, p < 0.001) and ulnar (5.7 vs 4.1 mm, p < 0.001) nerve territories. Smoking status, sex, age and diabetes did not significantly affect two-point discrimination outcomes. In conclusion the endoscopic release of the transverse carpal ligament decompresses the carpal tunnel and Guyon\'s canal, demonstrating improvement in two-point discrimination in both the ulnar and median nerve distributions.
El síndrome de túnel carpiano es la compresión sintomática del nervio mediano al nivel de la muñeca. Se caracteriza por un aumento de presión dentro del túnel y una disminución de la función del nervio a ese nivel. La liberación del túnel carpiano descomprime el canal de Guyon, con mejoría sintomática y en la prueba de discriminación de dos puntos en la distribución del nervio cubital. Hipotetizamos que la liberación endoscópica mejora de la misma manera en la distribución del nervio cubital. Este trabajo incluye 143 pacientes que tuvieron liberación endoscópica del túnel carpiano entre abril del 2016 y junio del 2019 en un hospital Universitario de la comunidad. Se evaluaron retrospectivamente las historias clínicas para los datos demográficos, los resultados pre y post quirúrgicos en la prueba de discriminación de dos puntos y complicaciones. Se analizaron los efectos del sexo, edad, tabaco y diabetes en los resultados de la prueba de discriminación de dos puntos para los nervios cubital y mediano. Hubo mejoría significativa post quirúrgica en la prueba de discriminación de dos puntos para los nervios mediano (7.7 vs 4.4 mm, p < 0.001) y cubital (5.7 vs 4.1 mm, p < 0.001). Fumadores, sexo, edad, y diabetes no afectaron de forma significativa. Concluimos que la liberación endoscópica del ligamento transverso del carpo descomprime el túnel carpiano y el canal de Guyon con mejoría en la prueba de discriminación de dos puntos para los nervios cubital y mediano.

Ulnar tunnel syndrome is compression of the ulnar nerve at the level of the wrist within Guyon\'s canal. It is most commonly caused by a ganglion cyst but may also be secondary to fractures, inflammatory conditions, neoplasm, vascular anomalies, aberrant musculature or a combination of these. Assessment should include a detailed history focusing on duration, site and progression of symptoms. The level of compression can be estimated clinically on examination by assessing motor and sensory changes in the hand. Investigations are used to confirm diagnosis or to clarify the underlying cause. X-rays and computed tomography can be used to exclude fractures. Ultrasound is used to diagnose ganglion cysts and vascular anomalies, and can localise the level of compression. Nerve conduction studies can be used to support the diagnosis and look for proximal compression. Mild symptoms can be managed non-operatively. Surgical exploration and decompression is the gold standard treatment for neuro-compressive causes with largely good outcomes.

Focal ulnar neuropathy at the wrist is a rare but problematic disorder often associated with the unique anatomy of this nerve as it courses through Guyon\'s canal, a superficial fibro-osseous tunnel in the proximal ulnar palm. The electrophysiologic features of this disorder have been well-characterized, but the sonographic anatomy of the nerve across the wrist and palm has yet to be systematically described in normal and abnormal states. In this review, we describe the basic anatomy and the sonographic appearance of the nerve in the wrist and palm in normals and individuals with pathology. The value of using US in conjunction with electrodiagnostic testing is emphasized as the two tests together provide critical information regarding etiology, predisposing factors, and functional significance. Furthermore, ultrasound is useful as a patient educational tool to promote behavioral changes that assist in nerve recovery when pathology is related to repetitive stress.

OBJECTIVE: The aim of this study was to evaluate the outcomes of open reduction and internal fixation (ORIF) in hamate hook fractures and review the literature on this surgical procedure.
METHODS: We report the outcomes of ORIF of hamate hook fractures in 13 consecutive patients (12 men and 1 woman; mean age: 32 years (range, 22-48 years)). In eight patients (61%) the fracture was associated with ulnar nerve neuritis in Guyon\'s canal. We assessed the following clinical data: age, sex, mechanism of injury, side of the injured hand and associated lesions, fracture classification, average time from injury to correct diagnosis, surgical technique, complications, and length of follow-up. All patients underwent radiological imaging, including standard radiographs in two planes (anteroposterior and lateral projections), and a CT study. Functional outcomes evaluated were pain, range of motion, grip strength, Disabilities of the arm, shoulder and hand (DASH) and Mayo wrist score.
RESULTS: The mean follow-up was 36 months (range, 12-144 months). All 13 cases were treated with ORIF of the hook of the hamate. Mean VAS pain score was 5 preoperatively (4-9) and 1 (0-2) postoperatively. All patients returned to pre-injury level and only one patient felt pain on activity. Preoperative modified Mayo wrist score was 51 and the postoperative value was 94. All outcomes scores improved significantly from preoperative values. The patients who participated in sports postoperatively were able to do so at or near pre-injury levels. Postoperative average range of wrist motion was 76° in extension, 71° in flexion, 14° in ulnar deviation, and 21° in radial deviation. Mean grip strength in the hand with the hook fracture was 58 kg compared with 53 Kg in the unaffected hand. All patients returned to their pre-injury level of functioning after 10-12 weeks and there were no complications. Analysis of grip strength revealed values comparable with the unaffected hand.
CONCLUSIONS: ORIF of hamate hook fractures is a safe and effective technique to restore normal grip strength and return to pre-injury level. In cases of ulnar nerve neuritis, neurolysis of the deep palmar branch is mandatory.
METHODS: Level IV, Therapeutic study.