Nerve blocks at the wrist for carpal tunnel release revisited: the use of sensory-nerve and motor-nerve stimulation techniques

BACKGROUND AND OBJECTIVES: Because the median nerve at the wrist has mainly sensory endings, the aim of this study was to assess the response of the median nerve to nerve stimulation at the wrist and to evaluate the quality of median nerve block. A control group of patients who received blinded injections was analyzed and compared post hoc. METHODS: One hundred and eleven patients scheduled for ambulatory endoscopic carpal-tunnel release performed under median and ulnar nerve blocks at the wrist were prospectively studied. The blocks were performed with a nerve stimulator. Nerve-stimulation techniques were explained to the patient before the block was performed. The patient was trained to inform the anesthetist of their perception of an electrical paresthesia that was synchronized to the nerve stimulator. The anesthetist recorded the first response of the patient to nerve stimulation: sensory (S), sensory-motor (SM), or motor response (M). When the minimal stimulating current was obtained, an equal volume of 4 mL of 1.5% mepivacaine was injected on median and ulnar nerves. If necessary, a lateral subcutaneous injection of 2 mL of 1.5% mepivacaine was administered at the wrist crease in the musculocutaneous nerve area. Thirty-five patients who received blinded local anesthetics injections were included post hoc. Quality of anesthesia was compared between groups. RESULTS: Responses included 89 S (80.2%), 18 SM (16.2%), and 4 M (3.71%). No differences occurred in time to perform the block, minimal current intensity, and efficacy. More punctures were necessary in the M group compared with the S group and the control group (P < .05). The onset time of sensory blocks increased significantly in control-group patients (P < .05), but the duration of the nerve-block procedure decreased in comparison with the M group. Respectively, 10% and 20% of patients experienced mild or severe pain in the nerve-stimulation group and control group. At 20 minutes, the block was complete for the median and ulnar nerves in 96.4% and 85% of the nerve-stimulation patients and control patients (P < .05). Two patients in the control group experienced painful mechanical paresthesia. Neither permanent nor transient nerve injuries were observed during or after the nerve block or surgery. CONCLUSION: This study describes how infrequently an initial motor response is identified when a nerve stimulator is used on the median nerve at the wrist. A very high success rate of median and ulnar nerve block at the wrist is obtained by use of sensory or sensory-motor-nerve stimulation and less than 10 mL of anesthetic solution.     

A comparison of injection at the ulnar and the radial nerve in axillary block using triple stimulation

BACKGROUND AND OBJECTIVES: A triple-stimulation technique for axillary block consists of the localization and injection of 2 nerves, median and musculocutaneous, which lie superior to the axillary artery, and of 1 nerve, the radial, which lies inferior. However, in some patients, the ulnar nerve is located first during the search for the radial nerve. The aim of this study was to verify if an ulnar motor response could be considered a satisfactory endpoint as a radial motor response. METHODS: This study was a prospective, randomized, double-blinded study. Ninety patients received a triple-injection axillary brachial plexus block in which the radial nerve (group RAD) or the ulnar nerve (group ULN) was located and injected inferior to the axillary artery. Patients were assessed for sensory and motor block by a blinded investigator at 5-minute intervals over 30 minutes. RESULTS: A statistically significant higher overall block success rate was recorded in group RAD (91% vs. 73%), and this result was related to a larger success rate for anesthetizing the radial nerve (95% vs. 77%). A statistically significant shorter onset time of sensory block for the radial nerve was recorded in group RAD versus group ULN (9 +/- 5 min vs. 16 +/- 7 min), whereas the reverse was true for the ulnar nerve (13 +/- 7 min for group RAD vs. 10 +/- 3 min for group ULN). The time to perform the block was slightly but statistically significantly shorter in group ULN (6.5 +/- 1.7 min vs. 7.8 +/- 1.8 min). CONCLUSIONS: Local anesthetic injection at the ulnar nerve significantly reduces the efficacy and prolongs the onset time of the radial-nerve block when triple-stimulation axillary block is performed.     

Distal peripheral nerve blockade for patients undergoing hand surgery: a pilot study

BackgroundData are limited regarding the use of peripheral nerve blockade at the level of the forearm, and most studies regard these procedures as rescue techniques for failed or incomplete blocks. The purpose of the study was to investigate patients undergoing hand surgery with distal peripheral nerve (forearm) blocks and compare them with patients having similar procedures under more proximal brachial plexus blockade. No investigations comparing distal nerve blockade to proximal approaches are currently reported in the literature.MethodsMedical records were retrospectively reviewed for patients who had undergone hand surgery with a peripheral nerve block between November 2012 and October 2013. The primary outcome was the ability to provide a primary anesthetic without the need for general anesthesia or local anesthetic supplementation by the surgical team. Secondary outcome measures included narcotic administration during the block and intraoperative procedures, block performance times, and the need for rescue analgesics in the post anesthesia care unit (PACU).ResultsNo statistical difference in conversion rates to general anesthesia was observed between the two groups. Total opiate administration for the block and surgical procedure was lower in the forearm block group. There was no difference in block performance times or need for rescue analgesics in the PACU.ConclusionsForearm blocks are viable alternatives to proximal blockade and are effective as a primary anesthetic technique in patients undergoing hand surgery. Compared to the more proximal approaches, these blocks have the benefits of not causing respiratory compromise, the ability to be performed bilaterally, and may be safer in anticoagulated patients.     

Refinements in the technique of 'awake' electrical nerve stimulation in the management of chronic low ulnar nerve injuries

The standard technique in the management of chronic low ulnar nerve injuries includes excision of the neuroma and reconstruction using sural nerve grafts in the fully anaesthetised patient. It has been shown that using this standard technique, disappointing results may be observed and that significant improvement in results could be obtained if intra-operative matching of sensory and motor fascicles is performed. This study reports on eight patients with chronic ulnar nerve injuries managed using the technique of electrical fascicular orientation and sural nerve grafting. In all patients, intra-operative electrical stimulation of the fascicles in the proximal stump was done in the awake state. Several refinements in technique are described including detailing pre-operative patient education, anaesthetic considerations and in the technique of nerve dissection. Assessment was done using a sensory grading system mainly based on static two-point discrimination and a motor grading system based on intrinsic muscle function and key pinch power. At final follow up satisfactory sensory (S3+ or S4) and motor (M3 or M4) recovery was obtained in almost all cases. It was concluded that intra-operative electrical fascicular orientation was reliable and that our refinements in the technique ensured better communication with the patient during surgery, resulted in a smoother awakening without apprehension, and provided an easier nerve dissection with preservation of the blood supply of the distal nerve segment.     

Osteoid osteoma in the hand and wrist

Summary Twenty-seven patients were operated for an osteoid osteomas in the hand, by two surgeons in two hand surgery centers. Their mean age was 33 years. Nine were located in the carpus (2 scaphoids, 3 capitates, 2 lunates and 1 hamate), 4 in the metacarpals and 14 in the digits. Clinical presentation allows to separate two groups of patients. Group I consists of 17 patients with classical clinical signs including pain, oedema and/or palpable swelling accompanied by typical radiographic signs, usually located in the metacarpals and phalanges. In group II, 10 patients presented a more elusive diagnosis. These included carpal lesions, atypical radiologic signs and previously operated patients. More sophisticated imaging techniques were used, including angiograms (three cases), CT-scan (u cases, positive in 10), MRI (4 cases, positive in 3), thermography (2 cases). CT-scan was the most useful for precise localisation in the wrist to select direct approach. All patients had their tumor resected en bloc, 7 patients requiring cancellous bone grafts and 4 corticocancellous bone grafts. Surgical removal provided immediate relief in 25 of the 27 patients, maintained at a mean follow-up of 17 months.     

腕部桡尺神经浅支的解剖学研究

目的为在桡、尺骨远端骨折处经皮穿针固定提供一个安全进针区域,减少桡、尺神经浅支的损伤提供解剖学依据。方法成人前臂标本18侧,观察桡、尺神经浅支的走行规律。结果桡神经浅支从肱桡肌和桡侧腕长伸肌腱平均间穿出点与桡骨茎突纵向平均距离(L_1)为[(7．4±0．7)cm,(?)±s,下同]。其中16侧在穿出点与桡骨茎突纵向平均距离(L_2)为(4．5±0．6)cm处发出一级分支,称为尺侧支(Ⅰ)和桡侧支(Ⅱ)；尺侧支的桡侧分支(I a)与桡骨茎突的横向平均距离(L_3)为(1．0±0．3)cm,桡侧支与桡骨茎突横向平均距离(L_4)为(0．8±0．3)cm,纵向平均距离(L_5)为(1．5±0．4)cm。2侧桡神经浅支桡侧支被前臂外侧皮神经所替代。尺神经浅支手背支均从尺骨茎突的掌侧走行,与尺骨茎突距离为(0．9±0．3) cm。结论以桡骨茎突为中心,横向距离0．4cm．纵向距离0．6cm的椭圆形区域为桡神经分布相对盲区．从该区经皮克氏针固定桡骨远端,可有效地减少桡神经浅支损伤的发生率。尺骨远端骨折应从尺骨茎突背侧经皮进针相对较安全。     

桡骨远端骨折合并腕部尺神经损伤的诊断与治疗

目的总结桡骨远端骨折合并腕部尺神经损伤的发病机制、临床表现和治疗方法。方法对桡骨远端骨折合并尺神经支配区单纯掌侧感觉、运动或感觉和运动同时改变的7例患者，进行腕尺管探查尺神经松解术。结果术后随访时间为6～12个月，按中华医学会手外科学会上肢部分功能评定试用标准评定：优5例，良1例，可1例。结论部分伸直型桡骨远端骨折可合并腕部尺神经卡压，一经明确诊断即应早期行尺神经松解手术。     

Effect of infraorbital nerve block under general anesthesia on consumption of isoflurane and postoperative pain in endoscopic endonasal maxillary sinus surgery

Purpose. The efficacy of infraorbital nerve block in reducing isoflurane consumption and postoperative pain was evaluated in patients undergoing endoscopic endonasal maxillary sinus surgery (ESS) under general anesthesia. Methods. Fifty patients were randomly allocated to either the block group (n = 15) or the nonblock group (n = 25). After the establishment of general anesthesia with isoflurane, nitrous oxide, and oxygen, the patients received infraorbital nerve block with 1.0 ml of either 0.5% bupivacaine (block group) or normal saline (nonblock group) administered into the soft tissue in front of the infraorbital foramen. Systolic blood pressure during anesthesia and surgery was maintained at 85–90 mmHg by adjusting the inspiratory concentration of isoflurane, and its consumption was evaluated in both groups. Pain intensity at 15 min after the end of anesthesia was also evaluated on a five-point pain scale. Results. The consumption of isoflurane under a fresh gas flow of 6 l·min⁻¹ was 17.3 ± 6.5 ml·kg⁻¹·h⁻¹ (mean ± SD) in the block group and 27.4 ± 9.4 ml·kg⁻¹·h⁻¹ in the nonblock group during surgery (P < 0.001). Nicardipine was required during surgery less frequently in the block group than in the nonblock group (P < 0.01). Postoperative pain intensity was lower in the block group than in the nonblock group (P < 0.01). Conclusion. General anesthesia combined with infraorbital nerve block is effective in reducing the consumption of isoflurane and postoperative pain intensity in ESS. Received: April 4, 2000 / Accepted: February 13, 2001     

Lateral cervical epidural catheter placement using nerve stimulation for continuous unilateral upper extremity analgesia following a failed continuous peripheral nerve block

This case report describes the application of electrical stimulation (Tsui test) to confirm placement of a cervical epidural catheter for postoperative pain management in a patient with a failed brachial plexus block who underwent upper extremity surgery. An epidural catheter was easily advanced under nerve stimulation guidance to the surgical dermatome C4 level without any resistance from the C7-T1 level. Successful analgesia was achieved with a bolus of 2 mg ml(-1) ropivacaine 2 ml and fentanyl 20 microg, followed by a continuous infusion of 2 mg ml(-1) ropivacaine with 2 microg ml(-1) of fentanyl at a rate of 2 ml h(-1). This case reminds the clinician that cervical epidural analgesia may serve as an alternative to a difficult continuous peripheral nerve block. Electrical stimulation may also help to confirm cervical epidural catheter placement at the appropriate dermatome to provide effective analgesia with minimal side-effects.     

Complications of K-wire fixation of fractures and dislocations in the hand and wrist

Kirschner wire (K-wire) fixation of fractures and dislocations of the hand and wrist is a common procedure. Of the 590 K-wire fixations performed on 236 patients, 36 (15.2%) experienced complications which included osteomyelitis, tendon rupture, nerve lesion, pin tract infection, pin loosening or migration. There were no deep soft-tissue pin infections or pyarthrosis. Technical failure, mainly when the procedure was performed by residents, and poor patient compliance were the major causes of complications. K-wire fixation is a simple but demanding procedure that cannot be left to an inexperienced resident. Elimination of technical failure, supervision in the operating room, close monitoring, prompt treatment upon discovery of a complication, and improvement of patient compliance can reduce the rate of complications. Received: 30 October 2000     

Update on the surgical treatment for rheumatoid arthritis of the wrist and hand

Surgical procedures for the treatment of rheumatoid arthritis are aimed at restoring function and decreasing pain. Over the past four decades multiple procedures have been described in the management of early and late disease. This article will review the most common forms of surgery used in the treatment of rheumatoid arthritis.     

A plantar flexion response to nerve stimulation indicates needle misplacement in the epidural/spinal space during psoas compartment block

We report two cases of plantar flexion due to epidural misplacement of the needle during psoas compartment block, providing a response feedback for needle position during this procedure. In one case, the response occurred contralaterally, and in the other bilaterally. In the first patient, the cause of contralateral plantar flexion could not be determined and no injection was made. In the second patient, the anteriorposterior-fluoroscopic image showed that the tip of the needle was placed at the midline of the column. At this point, 3 ml of radiopaque medium was injected, and it diffused throughout the epidural space. Subsequently, single-shot epidural anesthesia was achieved by injection through this needle.     

The use of a selective peripheral median nerve block for pain-free early active motion after hand surgery

We describe a simple method in which a nearly selective sensory median nerve block is used for early motion exercises. In this method an 18-gauge epidural catheter with 3 side holes in the fine catheter tip is placed proximal to the carpal tunnel. A bolus of 5 mL of 0.25% bupivacaine is injected before a continuous infusion of 3 mL/60 min of 0.125% bupivacaine is started. This method allows a continuous and selective sensory blockade with preservation of motor function and proprioception for early motion after hand surgeries.     

尺神经手背支卡压所致腕尺侧痛的解剖和临床研究

目的 对尺神经手背支卡压引起腕尺侧痛的机理进行研究并探讨尺神经手背支卡压症的诊断和治疗。方法 对40侧福尔马林固定的成人尸体前臂部和腕部进行大体解剖和显微解剖。在临床上诊治了13例尺神经手背支卡压的病例并进行分析。结果 尺神经手背支在尺骨茎突以近5.6-6.8cm处尺侧腕屈肌（腱）深面内侧缘穿出,紧贴尺骨行走,在尺骨小头内侧分成2－3大支,其中的横支紧贴骨膜,横跨尺骨小头或绕经尺骨小头远端斜行向桡侧,腕关节活动和尺骨小头的位置改变极易对其造成损伤。临床发现患该症的患者尺骨小头远端或尺侧缘有一显著而局限的压痛点,其周围有局部的皮肤感觉改变。13个病例中,7例局部封闭,6例手术,其中9例随访4个月－1年,未见复发。结论 腕关节反复屈伸时尺神经手背支尤其是横支被牵拉和压迫是造成尺神经手背支卡压的解剖学基础。临床上对腕尺侧痛并有皮肤感觉改变的病例,应考虑尺神经手背支卡压的可能性。     

腕部尺神经损伤的显微修复

目的：探讨腕部尺神经损伤的治疗方法和疗效。方法：对62例腕部尺神经损伤，行神经外膜缝合34例，神经束膜缝合30例，结果：全部病例术后随访时间平均为2．5年，按顾玉东的单根神经功能研究标准评定，神经外膜缝合优良率为52．9％，神经束膜缝合优良率为83．3％，结论：腕部尺神经损伤后行神经束膜缝合疗效明显优于神经外膜缝合。     

Patients' experiences with multiple stimulation axillary block for fast-track ambulatory hand surgery

BACKGROUND: Ambulatory axillary block by multiple nerve stimulation (MNS) is effective and time efficient, but may be rejected by patients because of block pain. This prospective study assessed patients' anxiety and acceptance of this block, identified which of the components of blocking procedure is most painful (i.v. line insertion, repeated needle passes, local anesthetic injection, or electrical stimulation) and recorded patients' anesthetic preferences for the future hand surgery. METHODS: Upon arrival at the day unit, 100 unpremedicated adult patients without previous experience of peripheral nerve stimulation indicated on the visual analog scale (VAS; 0-100) their anxiety about the block. The blocking procedure was then explained step-by-step. After inserting the i.v. line and freezing the skin in axilla, four terminal nerves (musculocutaneous, median, ulnar, radial) were electrolocated using an initial current of 2 mA and a target current of 0.1-0.5 mA. Pain caused by the individual components of blocking procedure was assessed on VAS before the start of surgery. On the day after the operation, the patients reassessed their anxiety for the next axillary block and indicated which anesthetic method (block alone, block plus sedation, or general anesthesia) they would prefer for the future hand surgery. RESULTS: Before the block, 59 patients admitted being anxious about regional block (median anxiety VAS=27), compared with 42 patients (anxiety VAS=10) postoperatively: P<0.01. Median intensity of electrical stimulation pain was significantly higher (VAS=16) than pain of local anesthetic injections (VAS=8), i.v. line insertion (VAS=6) and multiple needle passes (VAS=5). However, only 53 patients categorized electrolocation as painful. Twenty-seven reported discomfort but not pain, and 20 patients described the sensation as 'funny' or 'strange'. None of the patients had surgical pain during operation. Mean duration of surgery was 77 min, and of hospital stay 166 min. Ninety-eight patients would choose the same block for the future hand surgery, 13 of which would like sedation before the block, and two patients did not wish to be awake during any surgery. Ninety-five patients were satisfied with fast-tracking. CONCLUSIONS: Fear of block pain is diminished after experiencing the blocking procedure. Electrical stimuli was perceived as painful by 53% of patients, and this pain was more intense than with other block components. The majority of our patients would choose axillary block without sedation for future hand surgery and are satisfied with fast-tracking.     

Synovial chondromatosis of the pisotriquetral joint producing ulnar nerve palsy

A case of synovial chondromatosis compressing the motor branch of the ulnar nerve of the left hand is presented. Radiographs demonstrated soft tissue calcification. The electrophysiological study confirmed denervation of the intrinsic hand muscles. During surgical exploration, synovial chondromatosis arising from the pisotriquetral joint compressing on the motor branch of the ulnar nerve was seen. Treatment consisted of pisiformectomy, partial synovectomy and removal of loose bodies.     

针刺联合颈部阻滞对麻醉效果影响的Meta分析

目的通过Meta分析的方法评价针刺联合神经阻滞应用于手术患者的麻醉效果。方法计算机检索Pubmed、Cochrane library、Embase、CNKI、维普和万方数据库,检索年限为数据库建库至2017年5月。收集所有关于针刺麻醉联合神经阻滞用于手术患者的随机对照试验(randomized controlled trial,RCT),按照纳入与排除标准筛选、提取与评估方法学质量。采用Rev Man 5.3软件进行统计分析。结果最终纳入5篇RCT文献,共计382例患者。Meta分析结果显示:与单独神经阻滞组(对照组)比较,针刺联合神经阻滞组(试验组)术中血压差(MD=-13.62,95%CI-15.41~-11.84,P0.001)和心率差(MD=-6.49,95%CI-8.61~-2.36,P0.001)明显减小,并且术后8 h(MD=-1.07,95%CI-1.38~-0.75,P0.001),12 h(MD=-1.11,95%CI-1.30~-0.93,P0.001)及24 h(MD=-0.15,95%CI-0.25~-0.04,P=0.006)VAS评分均明显降低。结论针刺联合神经阻滞可能具有改善围术期血流动力学波动,并能起到术后镇痛的作用。