Palmar Cutaneous Branch Of Median Nerve Research Articles

Innervation of thumb carpometacarpal joint: implications for diagnostic block and denervation procedures

IntroductionOsteoarthritis (OA) of the thumb carpometacarpal (CMC) joint is a common disorder that negatively impacts hand function. Denervation of the thumb CMC joint has emerged as a viable treatment option....

Risk Assessment of Injury to Palmar Cutaneous Branch of the Median Nerve Using High-Resolution Ultrasound.

ObjectiveTo evaluate the relationship between the palmar cutaneous branch of median nerve (PCBMN) and surrounding anatomical structures by using high-resolution ultrasound (HRUS) to assess the risk of PCBMN injury.MethodsThe PCBMN course and the characteristics of bilateral distal forearms and wrists of 30 healthy volunteers were identified. The distance between PCBMN and other anatomical structures at three different levels along its course were measured using HRUS. Moreover, the depth of PCBMN from skin and its cross-sectional area (CSA) were measured.ResultsHRUS showed the PCBMN in all subjects. PCBMN branched off from the radial aspect of the median nerve (MN) at 4.69±0.89 cm proximal to the bistyloid line (BSL) and extended radially toward the flexor carpi radialis (FCR) tendon. PCBMN was within the ulnar edge of FCR tendon sheath, and became more superficial and perforated the antebrachial fascia between the FCR tendon laterally and the palmaris longus (PL) tendon medially. PCBMN was located at 4.08±0.72 mm on the ulnar aspect of the FCR tendon and 4.78±0.36 mm radially on the PL tendon at BSL. At the distal wrist crease level, the PCBMN was located at 5.68±0.58 mm on the ulnar side of the FCR tendon. The PCBMN depth from skin at BSL and its branching point was 1.92±0.41 and 7.95±0.79 mm, respectively. The PCBMN CSA was 0.26±0.15 mm2 at BSL.ConclusionHRUS can be used to identify PCBMN and its relationship with other anatomical structures. Our data can be used to predict PCBMN location, and prevent complications associated with invasive procedures involving the wrist.

Injury of ulnar branch of palmar cutaneous branch of median nerve: an important cause of pillar pain after surgical treatment for carpal tunnel syndrome

Objective To find out the possible causes of pillar pain after surgical treatment for carpal tunnel syndrome through anatomical and clinical study. Methods Through the anatomical study of the surgical area of carpal tunnel syndrome in 6 cadavers (12 sides), the distribution rule of the nerve branches in this area was found. According to this rule, the incision design and entry route were improved and applied to the clinic, and the occurrence of pillar pain was analyzed. A statistical comparison was made between the occurrence of pillar pain in routine surgical and modified surgical in order to find out the possible causes of the occurrence of pillar pain. Results The nerve innervation in the surgical area of carpal tunnel syndrome was derived from the palmar cutaneous branch of the median nerve. The palmar cutaneous branch of the median nerve emerged off the palmar fascia 8.1 mm at the distal side to the zero point. There were 3 types of main branch including 16.7% in single branch, 33.3% in double branches and 50% in three branches. The nerve trunk of the single and double branches walked in the radial side of the thenar crease with several irregular fine branches to the ulnar side. The ulnar branch of the three branches went from the main trunk to the ulnar side at the site to zero point averaging 11.2 mm and crossed the thenar crease at the site to zero point averaging 14.6 mm. According to this, the operative method was designed: the incision was located at 0.5 cm of the ulnar side of the thenar crease. The incision was about 3.0 cm long, and the proximal end of the incision was at least 2.0 cm to zero point. After incision, only the transverse carpal ligament was cut to protect the palmar aponeurosis at the proximal end of the incision to zero point and avoid the injury of the ulnar branch of palmar cutaneous branch. 102 patients were performed with the improved surgery while 110 cases were treated by routine surgery. The incidence of pillar pain in the improved group was 12.7%, and that in the control group was 34.5% one month after the operation. The incidence of pillar pain in the improved group was 14.7%, and that in the control group was 41.0% 3 months after the operation. The two groups had significant differences (P<0.05). There was no significant differences between the two groups 6 months after the operation, and the pillar pain disappeared in all the patients one year after the operation. Conclusion The injury of the ulnar branch of the palmar cutaneous branch of median nerve may be an important cause of pillar pain after surgical treatment for carpal tunnel syndrome. Key words: Carpal tunnel syndrome; Anatomy; Palmar cutaneous branch; Pillar pain

Conduction of the palmar cutaneous branch of the median nerve.

The palmar cutaneous branch of the median nerve (PCBMN) usually arises about 5.5cm proximal to the radial styloid and innervates skin of the thenar eminence. The nerve may be injured by direct trauma or during surgery at the wrist. The action potential of the nerve was recorded in 50 nerves of 25 normal subjects, by antidromic stimulation of the median nerve 10cm from the surface recording electrode over the midthenar eminence. The mean latency and mean amplitude of the evoked response were 2.6 +/- 0.2msec and 12 +/- 4.6 mu v, respectively. The mean duration of the evoked potential was 1.78msec. The technique is simple and may be useful in evaluating lesions of the PCBMN.