Digital innervation patterns following median or ulnar nerve laceration and their correlation to anatomic variations of the communicating branch between these nerves

The midline of the ring finger is classically considered as the neural watershed between the median and ulnar nerve sensory territories on the palmar surfaces of the fingers. Variations of this division exist and may be explained by a communicating branch between the third and fourth common digital nerves. The palmar sensibility patterns of fingers were assessed with Semmes Weinstein filaments after either a complete median or an ulnar nerve transection in 43 patients. Eight out of nine observed sensibility patterns could be explained by known anatomic types and subtypes of the communicating branch. The type of communicating branch, but not its subtype, could be established in the one remaining pattern.     

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.     

Anatomic study of the ramus communicans between the ulnar and median nerves

The communicating branch between the fourth and third common digital nerves in the palm of the hand was studied. The incidence and branching pattern were studied in 53 dissected cadaveric hands. The "danger zone" in which the nerve is at risk during surgery was established using morphometric data. A communicating branch was found in 50 hands. It originated proximally from the fourth common digital nerve to join the third common digital nerve distally in 44 hands and traversed perpendicularly between the third and fourth common digital nerves in 4 hands. In the 2 remaining hands the branch left the third common digital nerve proximally to join the fourth digital common nerve distally. In 90% of the hands the ramus communicans crossed over in the middle third of the palm of the hand. As a cautious measure, hand surgeons should take into account that this structure could cross over anywhere in the middle three fifths of the palm.     

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.     

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.     

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.     

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.     

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.     

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.     

指固有神经背侧支的应用解剖学研究

目的 为指固有神经背侧支的临床应用提供解剖学基础。方法 观测12只新鲜成人手标本48个手指指固有神经背侧支出的出现率、直径、走向及分支。结果 示、中、环指及小指桡侧指固有神经发出的单一分支形成背侧支者占92．86％（78．84）,背侧支缺如者占7．14％（6．84侧）。各指背侧支均在近节手指近、中1／3平面发出,并从指侧面斜向指背远端走行。在近指间关节桡背（或尺背）侧向背面及中节指背发出2－5条分支。除小指外,2－4指指桡、尺侧背侧支的直径粗细均有显著性差异（P＜0．05）,桡侧＞尺侧。小指飞侧无指固有神经背侧支。结论 示、中、环及小指的桡侧指固有神经背侧支走向恒定,可包含在同指逆行岛状皮瓣内,适用于修复指腹软组织缺损。     

End-to-side repair of thenar motor branch of median nerve to the ulnar nerve after excision of the median nerve neurofibroma

A 13-year-old male patient suffering for the past 5 years with a gradually swelling and occasionally painful volar side of right forearm, presented to our clinic without any trauma. An end-to-side nerve repair performed between the ulnar nerve and thenar motor branch, and second common digital nerve to the digital nerve of the first finger for mend the sensorial, digital, and motor impairments related to the median nerve associated plexiform neurofibroma that occured after the excision of the tumor.     

Recognition of acutely lacerated ulnar nerve-median nerve palmar communicating branch. A case report

A 32-year-old man incurred a porcelain faucet handle laceration to the palm, including the third common digital nerve and an adjacent large communicating sensory ramus to the third common digital nerve from the superficial ulnar nerve. This case is the first reported recognition and repair of a freshly lacerated communicating ramus.     

顺行髓内针内固定术治疗第四、五掌骨骨折的解剖入路研究

目的 总结顺行髓内针内固定术治疗第四、五掌骨骨折的术后并发症,并进行手术入路的解剖学研究.方法 对112例掌骨骨折且接受了顺行髓内针内固定术治疗的患者进行随访,观察术后神经、肌腱的并发症.对16侧成人前臂标本进行解剖学研究,观察尺神经手背支及伸肌腱的走行特点,测量顺行髓内针内固定术治疗第四、五掌骨骨折的人针点到周围神经及肌腱的距离.方果 112例中有8.0%(9/112)的患者术后出现手背尺侧半感觉障碍,其中7例完全恢复,2例遗留症状.无肌腱粘连、肌腱刺激或断裂等并发症的发生.解剖学研究显示,第四掌骨入针点距尺神经手背支的中间支约(4.9±1.4)mm,距横支(12.9±2.8)mm,距小指指伸肌腱(2.8±1.5)mm,距小指固有伸肌腱(4.9±1.5)mm;第五掌骨入针点距尺侧支(4.7±2.1)mm,距中间支(5.7±1.5)mm,距小指固有伸肌腱(3.0±1.5)mm.方论 第四、五掌骨基底尺背侧为神经、肌腱的"裸区",是顺行髓内针内固定术治疗第四、五掌骨骨折相对安全的入针区域.但仍要谨慎操作,才能避免损伤.     

Outcome of contralateral C7 transfer to two recipient nerves in 22 patients with the total brachial plexus avulsion injury

The treatment of total brachial plexus avulsion injury is difficult with unfavorable prognosis. This report presents our experience on the contralateral C7 (CC7) nerve root transfer to neurotize two recipient nerves in the patients with total BPAI. Twenty‐two patients underwent CC7 transfer to two target nerves in the injured upper limb. The patients' ages ranged from 13 to 48 years. The entire CC7 was transferred to pedicled ulnar nerve in the first stage. The interval between trauma and surgery ranged from 1 to 13 months. The ulnar nerve was transferred to recipients (median nerve and biceps branch or median nerve and triceps branch) at 2–13 months after first operation. The motor recovery of wrist and finger flexor to M3 or greater was achieved in 68.2% of patients, the sensory recovery of median nerve area recovered to S3 or greater in 45.5% of patients. The functional recovery of elbow flexor to M3 or greater was achieved in 66.7% of patients with repair of biceps branch and 20% of patients with repair of the triceps branch (P < 0.05). There were no statistical differences in median nerve function recovery at comparisons of the age younger and older than 20‐years‐old and the intervals between trauma and surgery. In conclusion, the use of CC7 transfer for repair two recipient nerves might be an option for treatment of total BPAI. The functional recovery of the repaired biceps branch appeared to be better than that of the triceps branch. © 2013 Wiley Periodicals, Inc. Microsurgery 33:605–611, 2013.     

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.     

带神经的双侧胸脐皮瓣修复全手皮肤撕脱伤

目的 探讨全手皮肤撕脱伤的治疗方法。方法 采用带神经的双侧胸脐皮瓣修复全手皮肤撕脱伤、右侧皮瓣上的两根神经分别与手掌第1、第3指掌侧总神经吻合，左侧皮瓣上的两根神经分别与尺神经手背支和桡神经皮支吻合。结果 两例全部成功。随访12～15个月，患手有温度觉和触痛觉，尺侧接触台面时有敏感性触觉，且恢复部分握捏功能。结论 带神经双侧胸脐皮瓣修复全手皮肤撕脱伤是一种较好的方法，可在各级医院推广使用。