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

Absent palmar cutaneous branch of median nerve.

Dear Sir/Madam, A 67-year-old male presented with persistent symptoms of carpal tunnel syndrome 20 months following a carpal tunnel decompression performed under local anaesthesia. In addition, he was noted to have paraesthesia over the thenar eminence with a Tinel spot at the wrist crease radial to the flexor carpi radialis tendon. He then underwent re-exploration of the median nerve and its palmar cutaneous branch. An external neurolysis and a hypothenar fat flap were performed for the scarred median nerve. However when trying to identify the origin of palmar cutaneous branch, there was no side branch (radial or ulnar) evident up to 80 mm proximal to the wrist crease. The base of thenar eminence was explored further and two cutaneous nerve branches were identified. They were dissected more proximally and would appear to have originated from the superficial radial nerve (Fig. 1). No other cutaneous nerve was identified. Fig. 1 Anomalous sensory nerve branches to the thenar eminence Sensory supply to the base of the thenar eminence could arise from the median nerve, lateral antebrachial cutaneous nerve and superficial radial nerve [1]. The typical course of the palmar cutaneous branch of the median nerve is a branching from the median nerve approximately 5 cm proximal to the wrist. It runs on the ulnar side of flexor carpi radialis before crossing the flexor retinaculum. It divides into two branches, medial and lateral while crossing the flexor retinaculum. The lateral branch is larger while both supply sensation to the thenar eminence [2]. Although a number of anatomical variations of the palmar cutaneous branch had been described [1, 3–6], the incidence of its absence has not been documented. Hoppenfeld and deBoer report that a palmar cutaneous nerve may be absent being replaced by branches of the radial, musculocutaneous or ulnar nerves [2]. In our case, the branch appeared to be absent. Iatrogenic injury to the branch from carpal tunnel decompression is a recognised complication and could be a possibility in our patient. However there was no evidence of a transected nerve during the revision procedure. This case highlights the importance of appreciation of anatomical variations when exploring peripheral nerves and raises the possibility of absent palmar cutaneous branch of the median nerve.

Study on variations in the palmar cutaneous branch of median nerve

Introduction: Variations in the anatomy of nerves at wrist have been recognised to be of importance to surgeon. Attention has been called for injury to palmar cutaneous branch of median nerve as a cause of the painful dysesthesia that follows carpal tunnel surgery.A comprehensive evaluation in wrist region is essential to avoid complications. Objective: In present study the objective was to study the anatomic variationsin number and side of origin of palmar cutaneous branch from median nerve. Materials and Methods: The study included 51 hands from human cadavers at Department of Anatomy, Mysore Medical College & Research Institute, Mysore during the time period of 2011-13. The specimens were fixed in 10% formalin, finely dissected and the numbers and side of origin were noted. Results: The palmar cutaneous branch was present in all 51 specimens and it was located under the tendons of palmaris longus & flexor carpi radialis. The palmar cutaneous branch of median nerve was single in 46 specimens (90.18%) and in 5 specimens it was observed to be multiple (9.8%). In 50 specimens the palmar cutaneous branches originated from radial side of the median nerve (98.04%) and in only one specimen (1.96%) it originated on ulnar side of the median nerve. Conclusion: A key to carry out therapeutic and diagnostic procedures successfully on carpal tunnel depends on the knowledge of the possible variations of nerves which may be encountered. Such variations are not only more prone to iatrogenic injuries but they interfere in the correct interpretation of clinical conditions as well.

English

The present case report describes the variance in the course of palmar cutaneous branch of median nerve along with a variant head of biceps brachii muscle in a middle aged male cadaver during routine dissection of right & left upper limb respectively. In the course of palmar cutaneous branch of median nerve it was observed that it was originating approx. 3cm proximal to flexor retinaculum and passed beneath the flexor retinaculum instead of passing superficial to it as described in conventional anatomical textbooks. Along with it, the third head of biceps brachii was found to originate from shaft of humerus from superomedial part of brachialis and its lower end was attached to lower part of muscle belly.

Can palmar creases serve as landmarks for the deeper neuro-vascular structures?

Purpose The aim of this study was the examination of the superficial anatomy of palmar creases and their relation to deeper neuro-vascular structures.MethodsFour creases: distal wrist flexion crease, thenar crease, proximal palmar crease and distal palmar crease were evaluated with reference to the following structures: palmar cutaneous branch of median nerve, palmar cutaneous branch of ulnar nerve, the nerve of Henle, transverse palmar branches from ulnar nerve, recurrent motor branch of median nerve, radial proper palmar digital nerve to the index and the ulnar proper palmar digital nerve to the thumb, Berrettini’s communicating branch, ulnar nerve and artery, superficial palmar arch. We performed dissections of 20 cadaveric upper limbs derived from a homogenous Caucasian group. In our study we measured the location of surgically important structures with reference to palmar skin creases.Results Among the other observations we noticed that the palmar cutaneous branches of the median and ulnar nerves were located at least 0.5 cm away from the thenar crease. The superficial palmar arch was found between the thenar and proximal palmar crease and never crossed the proximal or distal palmar creases.ConclusionsThese anatomical dissections will provide reference material for further ultrasound studies on the arrangements of neuro-vascular structures in reference to superficial palmar creases.

How to prevent injury to the palmar cutaneous branch of median nerve and ulnar nerve in a palmar incision in carpal tunnel release, a cadaveric study

To identify palmar cutaneous branches of median nerve and ulnar nerve (PCBMN and PCBUN) and try to find a safe path at wrist and forearm in the decompression procedure of carpal tunnel syndrome. Ten formalin-fixed and five fresh-frozen cadaveric forearms were included in the study. The cross point of longitude of middle finger and distal wrist crease was defined as 0 point. Distal wrist crease (DWC) and 0 point were chosen as references for measurements. Several points on the pathway of PCBMN and PCBUN were measured. The average distance between the origin of the PCBMN and PCBUN to the DWC was 4.95 ± 0.88 cm, 10.12 ± 1.50 cm, separately. The average distance between DWC and the point where PCBMN and PCBUN separated from their trunk was found to be 2.09 ± 0.31 cm, 2.90 ± 0.50 cm, separately. The distances between PCBMN, PCBUN and 0 point at DWC level was found to be 0.61 ± 0.12 cm, 0.47 ± 0.31 cm, separately. The diameters of two cutaneous branches were 0.10 ± 0.02 cm, 0.11 ± 0.04 cm, separately. The general longitudinal palmar incision could avoid injuries to recurrent branch of median nerve and distal branches of palmar cutaneous nerve can be avoided macroscopically. The area about 5 mm ulnar and 6 mm radial to 0 point at wrist level was a relatively safe area.