Neuropraxia of the palmar cutaneous branch of the ulnar nerve during carpal tunnel decompression

Carpal tunnel syndrome is one of the most commonly encountered conditions in the hand clinic and carpal tunnel decompression is the most frequently performed procedure in hand surgery. It is an effective procedure for patients with carpal tunnel syndrome. However, there is a high risk of complications that can be avoided with an understanding of wrist anatomy, appropriate planning and execution. We highlight one such complication, a case of neuropraxia of the palmar cutaneous branch of the ulnar nerve that followed carpal tunnel decompression.     

Entrapment neuropathy of the palmar cutaneous branch of the median nerve concomitant with carpal tunnel syndrome: a case report

A case of the entrapment neuropathy of the palmar cutaneous branch of the median nerve, concomitant with carpal tunnel syndrome is presented. This report demonstrates that the Semmes-Weinstein monofilament test and nerve conduction studies can identify entrapment of the palmar cutaneous branch of the median nerve concomitant with carpal tunnel syndrome.     

腕管综合征内窥镜手术预防正中神经损伤的临床研究

目的 介绍腕管综合征内窥镜手术(endoscopic carpal tunnel release,ECTR)预防正中神经损伤并发症的方法.方法 利用彩色多普勒超声仪(B超)对37例74手患者术前进行检测.结果 71例正中神经走行在桡侧腕屈肌腱与掌长肌腱之间,3例走行在掌长肌腱与尺侧腕屈肌腱之间,并术中确认.结论 正中神经变异走行在掌长肌腱与尺侧腕屈肌腱之间是ECTR的禁忌证,B超能准确定位正中神经与掌长肌腱关系,避免内窥镜手术损伤正中神经,更具有简单、经济、方便可靠等优点.

Abstract：

Objective To introduce a method of preventing median never injury during endoscopic carpal tunnel release (ECTR). Methods Ultrasonography of both wrists was done to 37 patients of carpal tunnel syndrome who were going to undergo open release of the transverse carpal ligament. Structures in the carpal tunnel were visualized to guide surgical decision-making. Results Ultrasonography showed that median never lies between the tendon of flexor carpi radialis and palmaris longus in 71 patients and lies between the tendon of palmaris longus and flexor carpi ulnaris in 3 patients. These findings were confirmed during the surgeries. Conclusion It is a contraindication of ECTR if median never lies between palmaris longus and flexor carpi ulnaris. Ultrasonography can accurately reveal the relative position of median never to the palmaris longus tendon. Pre-operative ultrasonography of the wrist is a simple, inexpensive and convenient method to exclude these contraindications and thus prevent median never injuries in ECTR.     

Severance of the thenar branch of the median nerve as a complication of carpal tunnel release

Loss of thenar motor function was noted in two patients who were seen after surgical release for carpal tunnel syndrome. Both patients were clinically and electromyographically found to have denervation of the thenar muscles. The severed motor branch was identified, isolated, and repaired at reexploration (5 months and 14 months after surgery). Thenar function eventually returned in both patients.     

正中神经掌皮支的应用解剖

目的　为腕掌部手术避免损伤掌皮支提供解剖学基础。方法　对 5 0侧成人上肢标本的掌皮支来源、走行、分支、分布及其营养动脉等进行解剖学观测。结果　掌皮支在腕远横纹的“0”点近端(4 4 .9± 2 1.6)mm处发自正中神经桡侧 ,在该点近端 (18.6± 11.5 )mm处穿出前臂深筋膜后 ,紧贴深筋膜和屈肌支持韧带浅面 ,越豆、舟顶间线的中、外 1/3交点至手掌。在“0”点远端 (8.2± 3 .4)mm处穿出掌腱膜。掌皮支干长 (4 9.7± 2 5 .2 )mm ,起点处宽 (1.2± 0 .9)mm。掌皮支主要分支有 3支者占 5 2 %(2 6侧 ) ,2支者 3 4% (17侧 ) ,1支者 14 % (7侧 ) ,它主要分布于手掌的大鱼际区和掌中区。桡、尺动脉发出营养支 (84.69% )与掌皮支干伴行后进入神经 ,掌浅弓发出营养支 (89.62 % )直接进入掌皮支的手掌部分支。结论　腕掌部手术应靠近尺侧作纵切口以免损伤掌皮支     

Isolated compression neuropathy of the palmar cutaneous branch of the median nerve

A case of isolated thenar numbness, with an associated painful palmar wrist mass is presented. At operation, a palmar wrist ganglion compressing the palmar cutaneous branch of the median nerve was encountered. After ganglion excision the numbness in the palm was relieved, and there was no recurrence at 6 years follow-up.     

Granular cell tumor of the palmar cutaneous branch of the median nerve

Granular cell tumor rarely occurs in the hand. A patient with this tumor involving the palmar cutaneous branch of the median nerve, and twelve-month follow-up is discussed. This lesion, similar to neurofibromas, can infiltrate peripheral nerves and cannot be dissected from them. The lesion is probably of Schwann cell origin.     

Complete median nerve transection as a complication of carpal tunnel release with a carpal tunnel tome

A 48 year-old right-hand-dominant man presented to our institution with paresthesia and loss of feeling along the median nerve distribution of the right hand 1 week after undergoing minimally open carpal tunnel release with the Biomet Indiana Tome at another hospital. At surgery, transection of the median nerve was discovered and repaired. This is the first report of a complete median nerve transection using the revised carpal tunnel tome with a single-pass technique.     

正中神经掌皮支的局部解剖与临床意义

目的 为避免腕、掌部手术切口损伤正中神经掌皮支提供解剖学资料.方法 对52例成人上肢标本正中神经掌皮支的来源、走行、分支、分布、血管显微解剖等进行解剖测量.结果 52例标本均有掌皮支,50例自正中神经桡侧发出,2例自尺侧发出,走行在掌长肌腱和桡侧腕屈肌腱之间的深层.发出点距离0点(远侧腕横纹中点)为(45.2±21.2)mm,穿出前臂深筋膜处距离0点(19.8±12.3)mm,穿出掌腱膜处距离0点(8.2±4.3)mm,掌皮支主干长(49.2±24.2)mm,起点处宽(1.2±0.7)mm,掌皮支与舟骨结节中点的垂直距离为(8.3±2.8) mm.掌皮支分3支者31例(占59.6％),分2支者15例(占28.9％),1支者6例(占11.5％).掌皮支主要分布于鱼际区和掌中区,以直入式、伴入式和肌支式进入神经.结论 掌皮支的来源、行程均较恒定.为避免伤及正中神经掌皮支及其营养血管,在腕部手术切口应选在尺侧半(环指纵轴的尺侧),在掌部应靠近第四掌骨作纵切口.     

A case of neurofibroma of the palmar cutaneous branch of the median nerve

This case report describes a previously unreported entity, a neurofibroma of the palmar cutaneous branch of the median nerve. The lesion presented as a palmar mass with an overlying abnormality of the skin. Treatment consisted of excision of the lesion. Infiltration of the terminal branches of the nerve by the tumour prevented nerve reconstruction but provided a previously unknown diagnostic clue: fibrosis of an area of skin innervated by the involved nerve, which had the appearance of a callosity.     

High bifurcation of median nerve at the wrist causing common digital nerve injury in endoscopic carpal tunnel release

A 45-year-old right-handed woman was treated by endoscopic carpal tunnel release under local anaesthetic. When cutting the proximal half of the flexor retinaculum with the retrograde blade, she complained of an electric shock-like pain in her middle and ring fingers. Open exploration of the carpal tunnel was performed and a laceration of the middle/ring common digital nerve, which bifurcated at the unusually high level of the wrist crease, was found.     

Anomalous palmar cutaneous branch of the median nerve in the distal forearm: case report

Variations exist in the anatomy of the palmar cutaneous branch of the median nerve about the wrist. We report an anatomic variation in the course of the palmar cutaneous branch of the median nerve identified in a 17-year-old girl undergoing surgery for a scaphoid nonunion. Instead of coursing ulnar to the flexor carpi radialis tendon, deep to the antebrachial fascia between the tendons of the flexor carpi radialis and palmaris longus, the palmar cutaneous branch of the median nerve was noted to cross volar to the distal aspect of the flexor carpi radialis to lie on its radial aspect. Knowledge of the anatomic variant described in this report should encourage surgeons to dissect carefully as they expose the flexor carpi radialis during the exposure of the distal radius or scaphoid.     

Median innervated hypothenar muscle: anomalous branch of median nerve in the carpal tunnel

A hypothenar motor branch of the median nerve in the carpal tunnel was observed and its motor function was documented by direct intraoperative nerve stimulation in two patients having carpal tunnel releases. The hypothenar branch left the median nerve at the midcarpal tunnel area. It crossed the tunnel superficial to the flexor tendons and penetrated the transverse carpal ligament ulnarly to innervate the abductor digiti quinti. Such branching of the median nerve at this level has not been reported previously. Good visualization of the carpal tunnel and careful dissection of its content even in the so called safe zone ulnar to long axis of palmaris longus tendon is recommended.