Anatomy
Peter Houpt in Hand Injuries in the Emergency Department, 2023
The median nerve runs between the two bellies of the pronator teres muscle in the forearm. It continues between the flexor digitorum superficialis and profundus muscles to the carpal tunnel. During this course it branches off the anterior interosseous nerve to the m. flexor pollicis longus, the m. flexor digitorum profundus of the index finger and m. pronator quadratus. The median nerve itself innervates the m. flexor carpi radialis, the m. pronator teres, the four mm. flexor digitorum superficialis, the m. palmaris longus and the m. flexor digitorum profundus to the middle finger. At the level of the wrist, the median nerve is located on the ulnar side of the FCR and is covered by the palmaris longus tendon. Distally, the median nerve passes through the carpal tunnel underneath the transverse carpal ligament. The motor branch branches off to the thenar and innervates the m. opponens pollicis, the m. abductor brevis and half of the m. flexor pollicis brevis. Finally the median nerve branches off as a sensory nerve to the thumb, index, middle and radial half of the ring finger.
Contracture of Muscles of the Upper Limb: Severe Volkmann's Ischaemic Contracture of The Forearm
Benjamin Joseph, Selvadurai Nayagam, Randall T Loder, Anjali Benjamin Daniel in Essential Paediatric Orthopaedic Decision Making, 2022
Following wound healing and splinting in the corrected position, the next-stage surgery was done. The median nerve was identified and neurolysed. The anterior interosseous nerve was identified and isolated. A free gracilis myo-cutaneous flap was harvested and transferred to the forearm. The proximal end of the muscle was sutured to the medial epicondyle and remnant of the common flexor origin. The distal end was woven into the ends of the flexor digitorum profundus and flexor pollicis longus tendons under optimum tension (Figure 44.3). The nerve to gracilis was anastomosed to the anterior interosseous nerve, and the vessels were anastomosed to the brachial vessels in an end-to-side fashion. The perfusion of the transferred skin flap was carefully monitored (the appearance of the flap on the fifth postoperative day is shown in Figure 44.4).
Answers
Calver Pang, Ibraz Hussain, John Mayberry in Pre-Clinical Medicine, 2017
This scenario describes carpal tunnel syndrome, a condition due to compression of the median nerve as it travels through the carpal tunnel at the wrist. Hence, patients will present with signs and symptoms associated with median nerve functions. This would result in reduced sensation to the lateral part of the palm and lateral three and a half fingers on the palmar surface of the hand. In addition, the thenar muscles and lateral two lumbricals would be affected resulting in loss of co-ordination and strength of the thumb and flexion, and extension of index and middle fingers at the metacarpophalangeal and interphalangeal joints, respectively. Option (a) describes damage to the radial nerve, option (b) is damage to the ulnar nerve, option (c) is damage to the adductor pollicis and option (d) is damage to the extensor pollicis brevis.
Tuberculous flexor tenosynovitis around the wrist causing massive tendon disruption: a case report
Published in Modern Rheumatology Case Reports, 2019
Mitsuhiko Takahashi, Tetsuya Hirano, Kenji Kondo, Tadashi Mitsuhashi
Carpal tunnel symptoms were not detected throughout the clinical course, but all the flexor tendons that pass through the carpal tunnel were disrupted in association with the tuberculous lesions. The median nerve is typically affected in the carpal tunnel but was unaffected in this case. We do not have a plausible explanation for this particular clinical presentation. The lack of these symptoms, however, might be attributed to the delayed presentation and disease progression. Another concern is whether a functional tendon reconstruction should be performed after resolution of infection. We had planned reconstructive surgery when the absence of recurrence was confirmed after cessation of the anti-TB treatment, and if the patient consented. Karunadasa et al. reported staged tendon reconstruction after single flexor tendon rupture due to tuberculous tenosynovitis [4]. They performed free tendon graft 4 months after implantation of a tendon spacer. In this case, the remaining wrist flexors or extensors could be used for tendon reconstruction. However, this would have been quite difficult because of the massive tendon disruption as well as the dilapidated tendon gliding floor and subluxation of the carpal bones. Radio-carpal arthrodesis would be necessary before the tendon reconstruction.
Monophasic synovial sarcoma mimicking schwannoma: a case report of a rare peripheral nerve tumor and literature review
Published in Neurological Research, 2023
Crescenzo Capone, Alessandra Turrini, Giulio Rossi, Vanni Veronesi, Carlo Sacco, Guido Staffa
We report the case of a 64-year-old, right-hand dominant man, with no significant past medical history, who came to our attention due to a slow-growing painful right axillary neoformation. The patient had already noticed it in previous years, but he did not give it much importance. On medical examination, we observed a moderately tender mass on the right axillary cave, approximately 25 mm in size, at the level of the deltopectoral junction. The patient did not show any motor or sensory impairments and the neurovascular examination was within normal limits. No history of neurofibromatosis type 1 (NF1) was reported or diagnosed. Electrodiagnostic tests, including electromyography and a nerve conduction study of the median nerve, were within normal limits. A first diagnosis as schwannoma of the right brachial plexus was made and the patient underwent ultrasonography and magnetic resonance imaging (MRI) with intravenous contrast infusion which showed a 3.1 × 2.2 × 2.0 cm, ovoid, lobular, heterogeneous mass arising from the posterior cord of the right brachial plexus. During T1- and T2-weighting, the mass was brighter than skeletal muscle with intense contrast enhancement (Figure 1). The radiologist’s impression confirmed the hypothesis of a probable neurofibroma or schwannoma.
9 years’ follow-up of 168 pin-fixed supracondylar humerus fractures in children
Published in Acta Orthopaedica, 2018
Noora Tuomilehto, Antti Sommarhem, Aarno Y Nietosvaara
36 (22%) of the 166 patients with Gartland III fractures had clinical findings of either median (19), ulnar (7), radial (7), or median and ulnar (3) nerve injury at discharge (even minor findings were recorded). Normal motor and sensory findings were recorded in 13 of these 36 patients preoperatively (1 median and ulnar, 3 ulnar, 3 radial, and 6 median nerve palsies). Electromyography (EMG) was undertaken on 18 of these 36 patients with no (11) or partial recovery within 3–6 months. 1 patient’s (primary treated by a consultant) median nerve was found partially entrapped in the fracture gap, released and repaired with subtotal recovery 1 year after fracture. All other patients’ sensorimotor functions recovered. Permanent nerve injury rate as a complication of treatment was thus 0.4%.
Related Knowledge Centers
- Brachial Plexus
- Brachialis Muscle
- Carpal Tunnel
- Carpal Tunnel Syndrome
- Spinal Nerve
- Teres Major Muscle
- Nerve
- Cervical Spinal Nerve 8
- Thoracic Spinal Nerve 1
- Biceps