|
斯坦福大学神经科最近在J Trauma杂志发表了一份综述文章，对成人创伤性神经损伤的病因、临床表现、诊断、处理进行了知识更新。急诊外科或创伤病房常常会遇见合并疑似神经损伤的创伤患者，对于此种情况，患者最为担心的是神经损伤确定后要不要急诊手术处理。对此问题，本篇综述进行了简要的概述，现将处理部分摘抄如下，如需原文，请在文末留言处留下邮箱号。 文章doi： 10.1097/TA.0000000000002081 sci-hub暂时还下载不了该文章 Initial management of traumatic nerve injuries largely depends on the mechanism and type of injury. 创伤性神经损伤的初步处理很大程度上取决于受伤机制和损伤类型。 In general, the “rule of 3s” can be applied.(1) 记住3s：3天，3周，3月 具体见文末流程图 For open, clean, sharp nerve injuries, surgical exploration and repair should be undertaken within 3 days following the injury. For open, ragged, contusion injuries, definitive repair should be performed around 3 weeks following the injury, but the ragged ends of the nerve should be tagged within the first several days following the trauma, when possible. Finally, for closed injuries, the decision for surgery is typically made around 3 months following trauma (Figure 2). For nerve transections, the best outcomes are achieved with tension-free primary repair of healthy proximal and distal ends of the nerve. A tension-free repair is important, as tension at the site of coaptation creates a milieu that is not conducive to nerve regeneration by creating tissue ischemia and scar formation.(14) In one large series of brachial plexus lacerations, good outcomes were achieved in 81% of patients with primary suture, 69% with secondary suture (delayed direct repair), and 53% with secondary graft repair.(15) With nerve transections, whether blunt or sharp, the nerve ends retract over time. With significant retraction, tension-free primary repair becomes impossible. Thus, for sharp injuries, the best outcomes are achieved with primary repair, which is easiest to achieve soon after trauma before significant retraction can occur. For ragged transections, the same principles apply but achieving these goals is slightly different. With ragged transections, the zone of injury is not completely defined at the time of trauma. The zone of injury will declare itself over the ensuing several weeks. Because healthy nerve ends are needed for repair, the recommendation is to allow enough time that the evolution of the zone of injury is complete. In order to prevent significant retraction, the injured nerve ends are tagged to a local structure such as muscle fascia. After allowing time for the evolution of the zone of injury to be completed, typically 2-3 weeks, the surgeon can then return to the operating room and resect the injured, scarred ends of the nerve and if the ends were tagged preventing retraction, still potentially perform a direct repair without an intervening graft. In most cases, even with tagging the nerve ends, a direct repair cannot be performed and an intervening graft is needed. Nonetheless, tagging the nerve ends facilitates finding them in the second operation and also prevents retraction, shortening the length of the needed graft. Generally, with a gap of up to 3 cm a tension-free repair can still be accomplished, if the injury is in a location where additional length can be gained. Even short gaps may be difficult to bridge with a tension-free repair in some locations (e.g., the forearm and lower leg) and will require an intervening graft. With gaps exceeding 3 cm in any location, an intervening graft is typically needed.(15, 16) Use of an intervening graft means that regenerating axons must cross two sites of coaptation, as opposed to one with direct repair. At each site of coaptation, axons are lost, thus reducing the number of axons reaching the distal target and decreasing outcomes.(17) This is associated with comparatively worse outcomes. Furthermore, as graft length increases, associated neurologic outcomes decrease.(18) Grafts longer than approximately 6 cm seem to be associated with poor outcomes. As a general principle, the length of the graft should be minimized, while still facilitating a tension-free repair. For patients presenting with open nerve injuries to centers without a peripheral nerve specialist, initial management should consist of management of acute, life-threatening injuries and stabilization of injuries to avoid progressive deficits according to typical trauma protocols. The nerve ends should be identified and clipped to a surrounding, fixed structure such as the muscle fascia. For clean, sharp injuries, following stabilization, the patient should be transferred to a center with a peripheral nerve specialist for prompt nerve repair, when possible. For blunt, ragged transections, the nerve ends should be similarly tagged. The patient should then be referred at discharge for urgent outpatient evaluation at a center with a peripheral nerve specialist in order to facilitate delayed exploration and repair. For closed injuries, upfront management consists of performing a careful and thorough neurologic examination to serve as a baseline, with referral to a center with a multidisciplinary nerve injury/brachial plexus program for further evaluation and management. Traumatic nerve injuries should be maximal at onset. Progressive neurologic deterioration requires further investigation for a secondary cause such as a compressive hematoma. Secondary causes should be promptly managed. Closed injuries require serial examination, typically with serial electrodiagnostic studies, to determine appropriate management. Spontaneously recovering nerves should be allowed to recover. Thus, identification of small gains is vital to making an informed management decision. For those patients not displaying sufficient spontaneous recovery by 3-6 months post-injury, surgery is typically recommended. Early referral facilitates an appropriate surgical decision- making time frame. With modern primary nerve surgery options, good outcomes can be achieved many times for patients who do not spontaneously recover. Primary nerve surgery options include neurolysis, nerve graft, and nerve transfer. The surgical strategy depends on the timing of patient presentation, specific nerve(s) injured, type of nerve injury, and intraoperative gross and electrodiagnostic findings. Secondary musculoskeletal options such as tendon transfer, free muscle transfer, and joint fusion are also available but are outside of the scope of this review. The use of intraoperative neurophysiologic monitoring, including nerve action potentials (NAPs), helps facilitate intraoperative decision-making and is an important component of any surgical plan. The use of NAPs is particularly important for lesions that are found to be in continuity, which are the majority of peripheral nerve injuries.(19) In cases where a nerve action potential is obtained across the site of injury, typically neurolysis only should be performed, as the lesion likely to continue recovering.(20) In a large series of brachial plexus injuries, 92% of patients had a good outcome with neurolysis alone when NAPs were present.(15) In another series of penetrating missile injuries, 94% of patients had a good outcome with neurolysis alone when NAPs were present.(21) An important component of early referral to a multi-disciplinary nerve injury program is early initiation of physical and occupational therapy and continued therapy postoperatively. Early and ongoing therapy is important for: 1. maintaining supple joints and avoiding contractures while awaiting return of neurologic function, 2. maximizing compensatory mechanisms, 3. implementing braces and orthotics to maximize function, 4. to help in cortical retraining particularly following nerve transfers, 5. to aid with pain control through hyperesthetic desensitization, and 6. to aid in sensory re-education.(22) Any operative intervention is less likely to have a good outcome if a comprehensive rehabilitation program is not part of the multidisciplinary approach. Early range of motion exercises following nerve injury are particularly important to maintain supple joints that are capable of regaining active movement with reinnervation. Pain management is another important component of management for nerve injuries. Neuropathic pain can be severe and is best managed with multi-modal therapy. In fact, following brachial plexus injuries, pain is the most significant independent predictor of disability.(23) Again, a multidisciplinary approach from a team with expertise in post-nerve injury pain will yield the best results, which is another reason to favor early referral. Pain management strategies often consist of a combination of medications, desensitization therapy, pain psychology, and surgical or procedural options.(24-29) Commonly utilized medication options include gabapentin, pregabalin, duloxetine, or nortriptyline. Surgical or procedural options that may be considered include nerve graft repair, neurolysis, spinal cord stimulation, dorsal root entry zone lesioning, peripheral nerve stimulation, and pulsed radiofrequency. Next, we highlight some common traumatic nerve injuries to point out management options and to bring to light the outcomes that can be achieved with modern surgical strategies combined with appropriate initial management. While nerve injuries are devastating, with current techniques there is hope for meaningful recovery with appropriate initial and definitive management. Upper trunk brachial plexus injuries commonly result from motor vehicle accidents and result in the loss of C5- and C6-innervated muscle function. A common nerve transfer strategy includes spinal accessory to suprascapular nerve transfer, radial nerve triceps branch to axillary nerve transfer, and ulnar nerve fascicle to biceps branch of the musculocutaneous nerve transfer.(30-35) Specifically for elbow flexion, in one systematic review, 83% and 56% of patients achieved at least Medical Research Council (MRC) grade 4 (i.e., movement against gravity plus moderate resistance) or greater elbow flexion with nerve transfer and nerve graft repair, respectively.(36) Radial nerve injuries commonly occur in association with humerus fractures. When possible, it is important to evaluate radial nerve function prior to any operative reduction and fixation in order to differentiate radial nerve injury associated with the fracture from iatrogenic injury associated with humeral fixation. Iatrogenic injuries should be explored to rule out entrapment by the operative hardware, whereas radial nerve injuries associated with the fracture are treated as closed injuries (Figure 3). Exceptions to this include open fractures, fractures associated with vascular injury, and fractures requiring internal fixation, in which case the radial nerve should be explored simultaneously.(37) Some centers now favor exploring all radial nerve injuries associated with humerus fracture early in order to grossly and electrophysiologically characterize the injury.(38) The radial nerve recovers remarkably well. For lesions in continuity, if NAPs are present more than 95% recover at least anti-gravity wrist extension. When NAPs are absent, a good recovery can still be expected with more than 90% of direct repairs and more than 85% of graft repairs recovering anti-gravity wrist extension.(39) Injury to the ulnar nerve above the proximal forearm is difficult to manage. The long distance from the point of injury to the motor endplates of the hand intrinsic muscles has led to poor outcomes for hand intrinsic function following direct or nerve graft repair.(40-43) New nerve transfer strategies have shown promise and can be considered in addition to or in place of traditional nerve graft repair for high ulnar injuries. The anterior interosseous nerve can be used as the donor and coapted to the distal ulnar nerve in an end to end fashion as the definitive repair or in an end to side supercharging fashion to supplement a more proximal ulnar nerve repair.(44- 46) Early data support improvement in hand intrinsic function in comparison to traditional nerve graft repair alone.(44, 46) In fact, in the small comparative series by Baltzer and colleagues, 84% of the patients who had a supercharge end to side nerve transfer had some recovery of ulnar-innervated hand intrinsic muscle function.(44) 上流程图 |
|
|
