Unusual anatomic variation of palmar sensory branches of the ulnar nerve: a case report.

Variant sensory branches of the ulnar nerve were encountered during a routine dissection of the palmar aspects of a cadaver hand. The variant branches were distributed to the ulnar half of the index, ulnar half of the middle, and radial half of the ring fingers. The communicating branch between the superficial ulnar branch and the third common digital branch of the median nerve was absent. Distribution of the median nerve sensory branches was normal. The clinical significance of this variation is discussed.     

Internal anatomy of the communicating branch between the ulnar and median nerves in the hand and its relevance to volar digital sensibility.

We studied the microanatomy of the communicating branch between the ulnar and median nerves in 26 adult cadaver hands to explain diminished sensibility in the fourth and fifth fingers we had observed in 2 patients after complete transection of the median nerve. Two new variations of the communicating branch were observed. In the first variation the communicating branch originated proximally from the third common digital nerve to distally join the ring finger ulnar digital nerve and the small finger radial digital nerve. In the second variation the ramus communicans traversed perpendicularly between the third and fourth common digital nerves with a crossover of nerve fibers.     

The surgical anatomy of ulnar and median nerve communications in the palmar surface of the hand

OBJECT: Sensation in the palmar surface of the digits is supplied by the median and ulnar nerves, with the boundary classically being the midline of the ring finger. Overlap and variations of this division exist, and a communicating branch between the ulnar and median nerve could potentially explain further variations in digital sensory innervations. The aim of this study was to examine the origin and distribution of the communicating branch between the ulnar and median nerves and to apply such findings to the risk involved in surgical procedures in the hand. METHODS: The authors grossly and endoscopically examined 200 formalin-fixed adult human hands obtained in 100 cadavers, and a communicating branch was found to be present in 170 hands (85%). Of the specimens with communicating branches, the authors were able to identify four notable types representing different points of connections of the branches. The most common, Type I (143 hands, 84.1%), featured a communicating branch that originated proximally from the ulnar nerve and proceeded distally to join the median nerve. Type II (12 hands, 7.1%) designated a communicating branch that originated proximally from the median nerve and proceeded distally to join the ulnar nerve. Type III (six hands, 3.5%) designated a communicating branch that traversed perpendicularly between the median and ulnar nerves in such a way that it was not possible to determine which nerve served as the point of origin. Type IV (nine hands, 5.3%) designated a mixed type in which multiple communicating branches existed, arising from both ulnar and median nerves. CONCLUSIONS: According to the origin and distribution of these branching patterns, the investigators were able to define a risk area in which the communicating branch(es) may be subject to iatrogenic injury during common hand procedures.     

Aberrant course of a communicating branch of the ulnar nerve to the median nerve contributing to hypothenar Hammer syndrome

This presentation represents a unique anatomic predisposition to the development of hypothenar hammer syndrome (HHS). In this case, a communicating branch of the ulnar nerve to the median common digital nerve of the ring finger was identified crossing volar to the superficial palmar arch. This relationship caused thrombosis of the superficial palmar arch proximal to this crossing nerve branch. The aberrant course of this nerve created a structural anomaly contributing to HHS, which ultimately mandated surgical intervention.     

Ulnar neuropathies in rheumatoid arthritis.

A loss of functional motor axons in the median and ulnar nerves occurred in half of thirty-three patients with rheumatoid arthritis. Weakness of small hand muscles may predispose to the development of ulnar deviation of the fingers in patients with joint disease at the radio-ulnar and metacarpophalangeal joints. There is no evidence that spasm of small hand muscles is a significant cause of ulnar deviation of the fingers in rheumatoid arthritis. Ulnar deviation of the fingers in rheumatoid arthritis is not due to selective impairment of the ulnar nerve or the deep palmar branch of the ulnar nerve even though ulnar deviation of the fingers can occur in association with such lesions and in the absence of joint disease.     

Anatomic variations in sensory innervation of the hand and digits

Anatomic dissections under microscopic magnification were performed on 30 fresh cadaveric hands to depict the course and interconnections of the sensory nerves to the digits. The dissections included the median nerve, the ulnar nerve, the superficial branch of the radial nerve, the dorsal branch of the ulnar nerve, and the dorsal branch of the proper digital nerve. The communicating branches between the median and ulnar nerves in the palm were found in 20 of the 30 (67%) specimens. The dorsal branch of the proper digital nerve was found to arise at or proximal to the A1 pulley zone in 62% of the long digits, more proximally than previously reported. The dorsal sensory nerves (the terminal branch of radial or ulnar sensory nerves) extending to the nail bed area were found in 46% of the digits, thus confirming that sensory supply to the dorsum of the distal phalanx and nail bed also arises from the dorsal sensory nerves. Four types of palmar-dorsal interconnections, located in the middle of the proximal phalanx, were found in the digits but not in the thumb. The presence of these branches indicates dual innervation of the dorsal and palmar side of the distal areas of the digits. These anatomic findings may help hand surgeons interpret discrepancies in sensory loss after either dorsal or palmar injuries.     

腕关节神经支配的解剖学研究

目的观察支配腕关节神经的来源、直径、数目及其行径;为去神经支配治疗腕关节疼痛提供解剖学资料。方法对10具20侧福马林固定的上肢标本,在手术显微镜下解剖并观察骨间后神经、前臂外侧皮神经、桡神经浅支、尺神经腕背支支配腕关节背侧的腕关节支;骨间前神经、正中神经掌皮支、尺神经深支及其主干支配腕关节掌侧的关节支。结果骨间后神经是支配腕关节背侧神经的主要来源;前臂外侧皮神经、桡神经浅支、尺神经腕背支也发支支配腕关节背侧。骨间前神经、正中神经掌皮支、尺神经深支发支参与支配腕关节的掌侧。结论用去神经支配的方法治疗腕关节顽固性疼痛主要适用于腕背侧的疼痛。     

Sensory communication of the median and ulnar nerves in the palm

A communicating branch between the median and superficial ulnar nerve in the palm of the hand has been described, but its relationship to the cutaneous anatomy of the hand has had little emphasis. Fifty preserved cadaveric hands were dissected. A communicating branch was found in 37 of 50 specimens. In 34 specimens, the connecting branch proceeded from the ulnar nerve to enter the median nerve distally; in three specimens it proceeded from the median nerve to reach the ulnar nerve distally. This study describes the communicating branch in relation to the distal crease of the wrist with the axis of the third webspace and fifth ray as the radial and ulnar borders, respectively. This study may aid surgeons in determining the likelihood of injury in trauma or during various surgical procedures.     

游离足底内侧皮瓣修复腕掌尺侧皮肤神经缺损

目的 探讨修复腕掌尺侧皮肤神经同时缺损的新方法.方法 2000年4月至2009年8月,应用游离足底内侧皮瓣修复腕掌尺侧皮肤并神经缺损5例.足拇趾胫侧趾底固有神经修复小指尺掌侧固有神经缺损1例;桡神经浅支修复尺神经及其深浅支缺损2例,修复尺神经浅支、第4指掌侧总神经及小指尺掌侧固有神经缺损1例;尺神经手背支修复尺神经浅支、第4指掌侧总神经及小指尺掌侧固有神经缺损1例.足底内侧血管与尺血管吻合.供区取同侧大腿皮片移植修复.结果 术后皮瓣及移植皮片全部成活.5例获得6个月至4年的随访,皮瓣质地好、外观满意,无手内肌萎缩和爪形手畸形,皮瓣和手指感觉恢复达S3～S3+,皮瓣两点辨距觉为7～10 mm.尺神经深浅支缺损病例术后综合评价均为优.结论 游离足底内侧皮瓣是修复腕掌尺侧皮肤神经缺损的有效方法.     

Palmar cutaneous branch of the median nerve

The palmar cutaneous branch of the median nerve was dissected in 25 fresh cadavers. The origin from the median nerve, the course, termination, and variability of the palmar cutaneous nerve are described in relation to two reference lines. In no case did a branch of the palmar cutaneous nerve extend ulnar to the axial line of the ring finger. The planning of incisions around the palmar aspect of the palm and wrist should be based on this anatomical knowledge.     

游离足底内侧皮瓣修复腕掌尺侧皮肤神经缺损

目的 探讨修复腕掌尺侧皮肤神经同时缺损的新方法.方法 2000年4月至2009年8月,应用游离足底内侧皮瓣修复腕掌尺侧皮肤并神经缺损5例.足拇趾胫侧趾底固有神经修复小指尺掌侧固有神经缺损1例;桡神经浅支修复尺神经及其深浅支缺损2例,修复尺神经浅支、第4指掌侧总神经及小指尺掌侧固有神经缺损1例;尺神经手背支修复尺神经浅支、第4指掌侧总神经及小指尺掌侧固有神经缺损1例.足底内侧血管与尺血管吻合.供区取同侧大腿皮片移植修复.结果 术后皮瓣及移植皮片全部成活.5例获得6个月至4年的随访,皮瓣质地好、外观满意,无手内肌萎缩和爪形手畸形,皮瓣和手指感觉恢复达S3～S3+,皮瓣两点辨距觉为7～10 mm.尺神经深浅支缺损病例术后综合评价均为优.结论 游离足底内侧皮瓣是修复腕掌尺侧皮肤神经缺损的有效方法.     

游离足底内侧皮瓣修复腕掌尺侧皮肤神经缺损

目的 探讨修复腕掌尺侧皮肤神经同时缺损的新方法.方法 2000年4月至2009年8月,应用游离足底内侧皮瓣修复腕掌尺侧皮肤并神经缺损5例.足拇趾胫侧趾底固有神经修复小指尺掌侧固有神经缺损1例;桡神经浅支修复尺神经及其深浅支缺损2例,修复尺神经浅支、第4指掌侧总神经及小指尺掌侧固有神经缺损1例;尺神经手背支修复尺神经浅支、第4指掌侧总神经及小指尺掌侧固有神经缺损1例.足底内侧血管与尺血管吻合.供区取同侧大腿皮片移植修复.结果 术后皮瓣及移植皮片全部成活.5例获得6个月至4年的随访,皮瓣质地好、外观满意,无手内肌萎缩和爪形手畸形,皮瓣和手指感觉恢复达S3～S3+,皮瓣两点辨距觉为7～10 mm.尺神经深浅支缺损病例术后综合评价均为优.结论 游离足底内侧皮瓣是修复腕掌尺侧皮肤神经缺损的有效方法.

Abstract：

Objective To explore a new method for repair of concurrent skin and nerve defect at palm and carpal on ulnar side. Methods From April 2000 to August 2009, five cases with concurrent skin and nerve defect at palm and carpal on ulnar side were reconstructed with free medial plantar flaps.Palmar nervous proprii defect at ulnar side of little finger was repaired by the first toe tibia nervous proprii in one case. The superficial branch of radial nerve was applied to repair the defect of ulnar nerve, as well as its deep or superficial branch in two cases. The superficial branch of radial nerve was also used to repair the defect of superficial branch of ulnar nerve, common palmar digital nerve of the fourth finger, Little finger ulnar palmar nervous proprii in one case. The dorsal branch of ulnar nerve was applied to repair the defect of superficial branch of ulnar nerve, common palmar digital nerve of the fourth finger, little finger ulnar palmar nervous proprii in one case. The vascular bundle of medial plantar flap was anastomozised with ulnar vascular bundle. The wounds at donor sites were covered with free skin grafts which were obtained from upper leg. Results All the flaps and skin grafts were survived completely. The five patients were followed up for six months to four years with no muscular atrophy or claw hand deformity. The esthetic result was satisfied. The Sensory of flaps and fingers recovered to S3 to S3+. The two-point discrimination distance on flaps was range from 7 mm to 10 mm. The postoperative comprehensive evaluation was excellent in the cases whose superficial and deep branches of ulnar nerve were repaired.Conclusions Free medial plantar flap is an effective method to repair concurrent skin and nerve defect at palm and carpal on the ulnar side.     

Reconstruction of high ulnar nerve lesions by distal double median to ulnar nerve transfer

Ulnar nerve lesions around the elbow often carry an unfavorable prognosis due to insufficient sensory and intrinsic muscle recovery. We present a series of 7 cases in which restoration of ulnar innervated intrinsic muscles of the hand and of skin sensibility was achieved. This was accomplished by a distal connection of the anterior interosseous nerve and the superficial sensory palmar branch of the median nerve to the motor and sensory components of the ulnar nerve at Guyon's canal. The length of the follow-up period ranged from 1 to 3.5 years. Results were graded by the Highet-Zachary scale. Good motor and sensory recovery was obtained in 6 cases; only return of protective sensation occurred in the remaining case.     

Anatomic study of variations of hypothenar muscles and arborization patterns of the ulnar nerve in the hand

PURPOSE: To show the variations in the hypothenar muscles and the arborization patterns of the ulnar nerve and to investigate the relationship between the hypothenar muscles and the ulnar nerve. METHODS: We performed an anatomic study of 35 hands from embalmed cadavers. After dissecting the ulnar side of the hand we recorded the number of hypothenar muscles and their variations, the site of the hiatus for the deep branch of the ulnar nerve, and the branching patterns of the ulnar nerve in each hand. We then investigated the relationship between the variations in the hypothenar muscles and the arborization patterns of the ulnar nerve. RESULTS: The abductor digiti minimi (ADM) had 1 belly in 6 hands, 2 bellies in 28 hands, and 3 bellies in 1 hand. The flexor digiti minimi brevis was absent in 8 hands, had 1 belly in 24 hands, and had 2 bellies in 3 hands. The opponens digiti minimi had 2 layers of origin and the deep branch of the ulnar nerve passed between these 2 layers in all hands. We classified the structural patterns of the hiatus into 3 types, the arborization patterns of the ulnar nerve into 5 types, and the branching patterns of the motor branch to the ADM into 4 types according to their morphologic characteristics. We found variations of the arborization pattern in which the deep branch originated from the ulnar trunk of the ulnar nerve distal to bifurcation in 3 hands, a communicating branch was present between the 2 sensory branches to the fingers in 3 hands, and the ulnar sensory branch pierced the ADM in 2 hands. CONCLUSIONS: We confirmed that the anatomic relationship between the ulnar nerve and the hypothenar muscle is complex and that the formation of the hiatus varies. This knowledge can assist the surgeon in the diagnosis and treatment of conditions associated with the ulnar aspect of the hand.     

The anatomy of the Berrettini branch: implications for carpal tunnel release

OBJECT: Dissections were performed in 100 fresh cadaver palms to determine the frequency with which superficial palmar communication between the median and ulnar nerves occurs and to what extent it might incur iatrogenic injury during endoscopic carpal tunnel release. METHODS: Superficial palmar communication between the median and ulnar nerves was present in 81% of the dissected hands. Superficial palmar communication, also known as the Berrettini branch, has been classified into four distinct types by Ferrari and Gilbert. Twelve hands were classified as Group 1 (communication in an oblique course from the ulnar to the median nerve originating >4 mm above the distal margin of the transverse carpal ligament [TCL]), 16 hands were classified as Group 2 (communication parallel to the distal margin of the TCL), and 53 hands were classified as Group 3 (communication in an oblique course from the ulnar nerve to the third common digital nerve, originating below the distal margin of the TCL). No hand fit the Group 4 classification (atypical communication). CONCLUSIONS: The Berrettini branch can be considered a normal anatomical finding. In 28% of the hands in this study, the branch was proximal to the edge of the distal ligament and, therefore, prone to iatrogenic injury in both one-portal and two-portal endoscopic surgery.     

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.     

Surgical implications of variations in hand collateral circulation: anatomy revisited

OBJECTIVES: One of the risks associated with harvesting the radial artery is hand ischemia. Accordingly, this study investigated the variations of the hand collateral circulation. METHODS: Fifty hands of cadavers were examined. Variations of the palmar arches were recorded. A classic superficial palmar arch was defined as direct continuity between the ulnar artery and the superficial palmar branch of the radial artery. A classic complete deep palmar arch was defined as direct continuity between the radial artery and the deep branch of the ulnar artery. RESULTS: A classic superficial palmar arch was found in 10% (5/50) of hands, and a classic complete deep palmar arch was found in 90% (45/50) of hands. The superficial palmar branch of the ulnar artery supplied blood to all fingers in 66% (33/50) of hands. Although the superficial palmar branch of the ulnar artery was continuous with the radial artery in only 34% (17/50) of hands (including the classic type of superficial palmar arch), every hand had at least one major branch connecting the radial and ulnar arteries. CONCLUSIONS: Variations in the terminations of the radial and ulnar arteries are common. Although the classic type of superficial palmar arch occurs relatively infrequently, there is always a significant anastomosis between the radial and the ulnar artery in the hand. This anatomic study confirms the presence of a collateral supply in the hand. In the absence of vascular disease, harvesting the radial artery should be regarded as a safe procedure.     

Multiple neurilemmomas of the median and ulnar nerves with a communicating branch in the same upper extremity.

A 30-year-old woman presented with multiple neurilemmomas in the same upper extremity. One originated from the main trunk of the ulnar nerve and two others from the sensory branch of the median nerve. A communicating branch in the palm from the ulnar nerve to the median nerve was confirmed. All the tumours were successfully enucleated and she made a satisfactory recovery.     

Multiple Neurilemmomas of the Median and Ulnar Nerves with a Communicating Branch in the Same Upper Extremity

A 30-year-old woman presented with multiple neurilemmomas in the same upper extremity. One originated from the main trunk of the ulnar nerve and two others from the sensory branch of the median nerve. A communicating branch in the palm from the ulnar nerve to the median nerve was confirmed. All the tumours were successfully enucleated and she made a satisfactory recovery.