G. Carl Huber (1865-1934): A Michigan Pioneer in Peripheral Nerve Injury and Regeneration.

The treatment of peripheral nerve injuries has seen tremendous innovations over the past century. Dr Gotthelf Carl Huber, an American immigrant and early experimental pioneer in the field of peripheral nerve injury, created a foundation of scientific knowledge for these advancements. At the beginning of his career, Huber published novel work in peripheral nerve injury, supporting the concept of Wallerian degeneration and demonstrating the use of nerve grafting for repair. As his scientific career evolved into other research areas at the University of Michigan, Huber's impact extended far beyond just the study of peripheral nerve injury. Because of the external forces of the First World War, Dr Huber's focus returned to translational projects concentrated on the treatment of neuromas and war time peripheral nerve injuries. Huber's scientific impact in the field of peripheral nerve injury and repair came as a result of his incredible work ethic, mentorship, and tremendous leadership qualities; through this, his work still influences clinical practice today, a century later.

A modified, less invasive posterior subscapular approach to the brachial plexus: case report and technical note.

The traditional posterior subscapular approach offers excellent exposure of the lower brachial plexus and has been successfully used in patients with recurrent thoracic outlet syndrome after an anterior operation, brachial plexus tumors involving the proximal roots, and postirradiation brachial plexopathy, among others. However, this approach also carries some morbidity, mostly related to the extensive muscle dissection of the trapezius, rhomboids, and levator scapulae. In this article, the authors present the surgical technique and video illustration of a modified, less invasive posterior subscapular approach, using a small, self-retaining retractor and only a partial trapezius and rhomboid minor muscle dissection. This approach is likely to result in decreased postoperative morbidity and a shorter hospital stay.

Silas Weir Mitchell and "The Strange Case of George Dedlow".

It has been said of Silas Weir Mitchell (1829-1914) that as a young man he was first among the physiologists of his day, in middle age first among physicians, and as an older man, one of the most noted novelists of his country. Mitchell's novels were written in his later life as a means to avoid boredom during lengthy summer vacations that were the norm for that time among the affluent members of Philadelphia society. These novels were criticized by some because of poor plots, which in some instances failed to move along, or for text that offered a stereotyped depiction of genteel society and the effects that war or personal disaster had on the characters' behavior The criticism came despite the fact that all critics agreed that Mitchell's portrayals of psychopathology in his fictional characters was unique and accurate. However, in his 30s, Mitchell had written and by chance had published a fictional short story that not only transcended such criticisms but became immensely popular. "The Strange Case of George Dedlow" portrays a union officer who was not a physician but who had some medical background and who sustained a series of war wounds leading to severe nerve pain, the author's first description of causalgia, multiple amputations, and the psychological as well as physical symptoms of phantom limb syndrome. The protagonist tells of his torments in the first person in a very engaging fashion. Thus, long before he began writing his, at that time, acclaimed novels in the 1880s, Mitchell wrote a piece of fiction that combines accurate and very important medical observations with fiction of great historical interest. The following rendering of this now classic short story includes selected quotes and some interpretation and is perhaps appropriate for this year, 2 years after the centenary year of his death in 1914.

Surgical management and outcome of iatrogenic radial nerve injection injuries.

OBJECTIVE: Iatrogenic injury to the radial nerve can occur following intramuscular or intravenous injections of the upper extremity. In this study, we review the injury mechanism, operative techniques, and outcomes of patients evaluated for radial nerve injection injuries. METHODS: Data from 33 patients evaluated by the senior authors (DGK and DHK) from 1970-2011 with radial nerve injection injuries were reviewed retrospectively. All patients had injury of the nerve during injection. All corrective operations involved the use of direct intraoperative nerve action potential (NAP) recordings and either neurolysis, neurectomy, or suture/graft repair. The Louisiana State University Health Science (LSUHS) grading system was used for clinical assessment. RESULTS: Of the 33 patients, 23 underwent surgical intervention for persistent neurological deficit and/or pain. Of the 24 patients evaluated for injuries at the arm level, 17 required surgical exploration and repair for persistent symptoms. Nine patients required external neurolysis because the lesions were in continuity and positive NAP recording was across the lesion. All of these patients achieved a Grade 4 or better in functional recovery. Eight patients with lesions in continuity but in which NAP could not be recorded underwent either end-to-end suture (7) or graft repair (1) following resection of a 3.0 cm non-recordable segment. All patients achieved Grade 3 or 4 functional recovery. Six patients with forearm injuries involving the superficial sensory branch of radial nerve underwent either neurolysis (3) or neurectomy (3). CONCLUSIONS: Surgical exploration may be indicated when pain or disabling motor deficits persist. Early diagnosis and operative intervention can achieve favorable outcomes through exploration and radial nerve repair.

Advances in the neurological and neurosurgical management of peripheral nerve trauma.

Peripheral nerve trauma frequently affects younger people and may result in significant and long-lasting functional disability. Currently, diagnosis and monitoring of peripheral nerve injury relies on clinical and electrodiagnostic information, supplemented by intraoperative electrophysiological studies. However, in a significant proportion of nerve injuries, the likelihood of spontaneous regeneration resulting in good functional outcome remains uncertain and unnecessary delays to treatment may be faced while monitoring for recovery. Advances in non-invasive imaging techniques to diagnose and monitor nerve injury and regeneration are being developed, and have the potential to streamline the decision-making process. In addition, advances in operative and non-operative treatment strategies may provide more effective ways to maximise functional outcomes following severe peripheral nerve trauma. This review discusses these advances in light of the current state of the art of management of peripheral nerve trauma.

Surgical outcomes of 156 spinal accessory nerve injuries caused by lymph node biopsy procedures.

OBJECT: Iatrogenic injuries to the spinal accessory nerve (SAN) are not uncommon during lymph node biopsy of the posterior cervical triangle (PCT). In this study, the authors review the operative techniques and surgical outcomes of 156 surgical repairs of the SAN following iatrogenic injury during lymph node biopsy procedures. METHODS: This retrospective study examines the authors' clinical and surgical experience with 156 patients with SAN injury between 1980 and 2012. All patients suffered iatrogenic SAN injuries during lymph node biopsy, with the vast majority (154/156, 98.7%) occurring in Zone I of the PCT. Surgery was performed on the basis of anatomical and electro-physiological findings at the time of the operation. The mean follow-up period was 24 months (range 8-44 months). RESULTS: Of the 123 patients who underwent graft or suture repair, 107 patients (87%) improved to Grade 3 functionality or higher using the Louisiana State University Health Science Center (LSUHSC) grading system. Neurolysis was performed in 29 patients (19%) when the nerve was found in continuity with recordable nerve action potential (NAP) across the lesion. More than 95% of patients treated by neurolysis with positive NAP recordings recovered to LSUHSC Grade 3 or higher. Forty-one patients (26%) underwent end-to-end repair, while 82 patients (53%) underwent graft repair, and Grade 3 or higher recovery was assessed for 90% and 85% of these patients, respectively. The average graft length used was 3.81 cm. Neurotization was performed in 4 patients, 2 of whom recovered to Grade 2 and 3, respectively. CONCLUSIONS: SAN injuries present challenges for surgical exploration and repair because of the nerve's size and location in the PCT. However, through proper and timely intervention, patients with diminished or absent function achieved favorable functional outcomes. Surgeons performing lymph node biopsy procedures in Zone I of the PCT should be aware of the potential risk of injury to the SAN.

Axillary nerve injury associated with sports.

OBJECT: The aim of this retrospective study was to present and investigate axillary nerve injuries associated with sports. METHODS: This study retrospectively reviewed 26 axillary nerve injuries associated with sports between the years 1985 and 2010. Preoperative status of the axillary nerve was evaluated by using the Louisiana State University Health Science Center (LSUHSC) grading system published by the senior authors. Intraoperative nerve action potential recordings were performed to check nerve conduction and assess the possibility of resection. Neurolysis, suture, and nerve grafts were used for the surgical repair of the injured nerves. In 9 patients with partial loss of function and 3 with complete loss, neurolysis based on nerve action potential recordings was the primary treatment. Two patients with complete loss of function were treated with resection and suturing and 12 with resection and nerve grafting. The minimum follow-up period was 16 months (mean 20 months). RESULTS: The injuries were associated with the following sports: skiing (12 cases), football (5), rugby (2), baseball (2), ice hockey (2), soccer (1), weightlifting (1), and wrestling (1). Functional recovery was excellent. Neurolysis was performed in 9 cases, resulting in an average functional recovery of LSUHSC Grade 4.2. Recovery with graft repairs averaged LSUHSC Grade 3 or better in 11 of 12 cases CONCLUSIONS: Surgical repair can restore useful deltoid function in patients with sports-associated axillary nerve injuries, even in cases of severe stretch-contusion injury.

Peroneal nerve injury associated with sports-related knee injury.

OBJECT: This study analyzes 84 cases of peroneal nerve injuries associated with sports-related knee injuries and their surgical outcome and management. METHODS: The authors retrospectively reviewed the cases of peroneal nerve injury associated with sports between the years 1970 and 2010. Each patient was evaluated for injury mechanism, preoperative neurological status, electrophysiological studies, lesion type, and operative technique (neurolysis and graft repair). Preoperative status of injury was evaluated by using a grading system published by the senior authors. All lesions in continuity had intraoperative nerve action potential recordings. RESULTS: Eighty-four (approximately 18%) of 448 cases of peroneal nerve injury were found to be sports related, which included skiing (42 cases), football (23 cases), soccer (8 cases), basketball (6 cases), ice hockey (2 cases), track (2 cases) and volleyball (1 case). Of these 84 cases, 48 were identified as not having fracture/dislocation and 36 cases were identified with fracture/dislocation for surgical interventions. Good functional outcomes from graft repair of graft length < 6 cm (70%) and neurolysis (85%) in low-intensity peroneal nerve injuries associated with sports were obtained. Recovery from graft repair of graft length between 6 and 12 cm (43%) was good and measured between Grades 3 and 4. However, recovery from graft repair of graft length between 13 and 24 cm was obtained in only 25% of patients. CONCLUSIONS: Traumatic knee-level peroneal nerve injury due to sports is usually associated with stretch/contusion, which more often requires graft repair. Graft length is the factor to be considered for the prognosis of nerve repair.

Inflammatory pseudotumor of nerve: clinicopathological characteristics and a potential therapy.

We sought to determine the clinical, electrophysiological, neuroimaging, and pathological features of inflammatory pseudotumor of nerve. Five patients were identified. All cases presented with a gradually progressive mononeuropathy with symptoms of weakness, sensory loss, and prominent neuropathic pain. The median duration of symptoms was 7 months (range 3-36 months). Electrophysiological results were in keeping with chronic axonal mononeuropathies with variable findings of active denervation and reinnervation. MRI demonstrated irregular, large masses involving and surrounding nerve with heterogenous signal characteristics on T1- and T2-weighted and post-contrast sequences. Histopathological features of the nerve slightly varied but shared commonalities including chronic inflammatory infiltrates, increased collagen, and increased numbers of microvessels. Axonal degeneration and decreased density of myelinated fibers were also noted. Three patients were treated with weekly courses of intravenous steroids for 3 months. All reported improvement in pain and weakness. Inflammatory pseudotumor of nerve is not a neoplasm and has reactive features of inflammation, increased vascularity, and marked fibrosis. It presents as a progressive axonal mononeuropathy with weakness, sensory loss, and pain that may be episodic. The primary pathophysiology is unknown but the inflammation and response to treatment suggests that there may be an immune component.

Resection and nerve grafting of a lipofibrohamartoma of the median nerve: case report.

OBJECTIVE AND IMPORTANCE: Our patient's symptomatology, history, physical examination, diagnosis, management, and functional outcome 1 year after surgical repair is presented and discussed in light of the current literature on lipofibrohamartomas. CLINICAL PRESENTATION: A 3-year-old boy presented to the Louisiana State University Nerve Clinic for evaluation and management because he was experiencing progressive symptoms of left hand swelling, dysesthesia, and impaired motor function. Physical examination demonstrated median nerve distribution motor impairment. Electromyographic/nerve conduction velocity studies also showed severely reduced conduction and amplitude of the median nerve response, and the magnetic resonance imaging findings were highly suggestive of lipofibrohamartoma. Hence, the presumed diagnosis was lipofibrohamartoma on the basis of imaging characteristics, location, and patient's age. INTERVENTION: The patient was brought to the operating room with the objectives of carpal tunnel release and biopsy. However, routine intraoperative nerve action potential recordings showed no or very poor responses, consistent with significant loss of median nerve function. On the basis of the intraoperative nerve action potentials, we opted to resect the tumor back to healthy median nerve fascicles and to perform graft repairs. Surgery proceeded uneventfully, without any complications. Pathology confirmed the diagnosis of lipofibrohamartoma. CONCLUSION: At 18 months postoperatively, the patient had excellent left hand function. On the basis of our experience with this patient, we believe that intraoperative nerve action potentials and the availability of usable proximal and distal nerve fascicles (which may be discernible on diagnostic imaging) are key factors in deciding whether a lipofibrohamartoma needs to be repaired or decompressed/biopsied. As illustrated by our case, we believe that resection and graft repair may be the best treatment option for some of these patients, and perhaps more so for pediatric patients.

Surgical management of the pelvic plexus and lower abdominal nerves.

OBJECTIVE: Nerves of the pelvic plexus and lower abdominal wall can lead to chronic neuralgias owing to a variety of causes, including iatrogenic injury, trauma, tumors, and primary nerve entrapment. Differentiating among the various neural etiologies can be a challenging task. Here, we present a large series of patients who underwent surgical treatment of these nerves, with an emphasis on diagnostic and therapeutic considerations. METHODS: Between 1970 and 2006, the senior authors (DGK and DHK) surgically treated 264 cases of neuralgia of the pelvic plexus and nerves. A retrospective analysis of the patients' history, physical, diagnostic examinations, and follow-up was performed. RESULTS: Twenty-five cases of solely ilioinguinal neuralgia and 24 cases of combined ilioinguinal neuralgias were treated. Of these, iatrogenic injury was the most common etiology. One hundred forty-five patients underwent surgical exploration for either femoral nerve injury (119 patients) or lateral femoral cutaneous compression (26 patients). Seventy-five percent of patients had femoral nerve injuries attributable to trauma (iatrogenic versus penetrating injuries), and the remaining 25% of patients had cystic masses or tumors. Fifty-two masses of the pelvic plexus were treated, including neurofibromas (68%), schwannomas (18%), malignant nerve sheath tumors (5%), and non-neural sheath tumors (9%). CONCLUSION: Effective surgical management of these complex neuralgias depends on a solid understanding of the surgical anatomy and proper diagnosis. Electromyography and local anesthetic blocks not only can provide insight into the diagnosis but also have predictive value in assessing which patients may benefit from neurectomy or neurolysis.

Nerve transfer surgery for adult brachial plexus injury: a 10-year experience at Louisiana State University.

OBJECTIVE: To review the clinical outcomes in our patients who have undergone nerve transfer operations for brachial plexus reconstruction at the Louisiana State University (LSU) over a 10-year period. A secondary objective is to compare clinical outcomes in patients who had only nerve transfer operations as compared with patients whose nerve transfers were supplemented with direct repair of brachial plexus elements. METHODS: Retrospective review of the medical records, imaging, and electrodiagnostic studies (electromyographic and nerve conduction studies) of patients with brachial plexus injuries who underwent nerve transfer operations at LSU over a period of 10 years. RESULTS: A total of 81 patients were treated between 1995 to 2005 at the LSU Health Sciences Center; 7 of these patients were lost to follow-up, leaving 74 patients, with an average follow-up of 3.5 years, for review. We evaluated recovery of elbow flexion and shoulder abduction. Ninety percent of patients with medial pectoral to musculocutaneous nerve transfers recovered to LSU grade 2 (Medical Research Council grade 3), and 60% of those patients with intercostal to musculocutaneous nerve transfer regained similar strength in elbow flexion. Shoulder abduction recovery to LSU grade 2 (Medical Research Council grade 3) after spinal accessory to suprascapular and/or thoracodorsal to axillary nerve transfer, was 95% and 36%, respectively. There was a tendency for better motor recovery when nerve transfer operations were combined with direct repair of plexus elements. CONCLUSION: Nerve transfers for repair of brachial plexus injuries result in excellent recovery of elbow and shoulder functions. Patients who had direct repair of brachial plexus elements in addition to nerve transfers tended to do better than those who had only nerve transfer operations.

Iatrogenic sciatic nerve injuries at buttock and thigh levels: the Louisiana State University experience review.

OBJECTIVE: To provide an overview of iatrogenic sciatic nerve injuries at the buttock and thigh levels, and to analyze results of the treatment provided at Louisiana State University Health Sciences Center-New Orleans. METHODS: The data from 196 patients were reviewed retrospectively. All patients had iatrogenic sciatic nerve injuries at the buttock and thigh levels and were evaluated and treated at the Louisiana State University Health Sciences Center between the years 1968 and 1999. One hundred sixty-four of these patients had injuries caused by injections at the buttock level, 15 sustained sciatic nerve injuries after a total hip arthroplasty, and 17 had iatrogenic damage at the thigh level. RESULTS: Patients with severe motor deficits underwent neurolysis if they had positive nerve action potentials, and end-to-end anastomosis or grafting if the nerve action potentials were negative. Operations were performed on 64 patients with injection injuries at the buttock level, on 15 with iatrogenic damage at the thigh level, and on 15 with deficits after total hip arthroplasty. Results were analyzed by the procedure performed and by the outcome in both the peroneal and tibial divisions. CONCLUSION: Patients with mild or no motor deficits and those with pain that was manageable did not undergo surgery and were treated conservatively. For patients with significant motor deficits and those with pain that was not responsive to pharmacological management, physical and occupational therapy required surgical intervention. Patients who had positive nerve action potentials required neurolysis only and had the best recovery, whereas those with negative nerve action potentials required more extensive intervention entailing reanastomosis or grafting and had worse outcome. In general, the outcome was better for the tibial than for the peroneal divisions, regardless of the type of intervention.

Management of one hundred seventy-one operative and nonoperative obstetrical birth palsies at the Louisiana State University Health Sciences Center.

OBJECTIVE: The management of obstetrical brachial plexus injury, often called birth palsy, remains one of the most controversial topics in pediatric neurosurgery. Most birth palsies have acceptable spontaneous recoveries, whereas only a minority require surgical intervention. A selective approach for surgery was used in this Louisiana State University Health Sciences Center (LSUHSC) series, for which the operative rate was 9%. At LSUHSC, the patient with obstetrical brachial plexus injury is followed for 6 to 9 months before surgery, which is performed if there is no satisfactory biceps and/or shoulder function. METHODS: This is a retrospective analysis of 169 patients with 171 palsies referred to LSUHSC for possible surgery. There were 76 patients with 77 birth palsies managed operatively and nonoperatively at LSUHSC between 1975 and 1991. An additional 93 patients with 94 palsies who were managed between 1992 and 2003 were included in this analysis. The results of initial and follow-up examinations using Eng's criteria for impairment ratings (IRs) were available for 151 of 171 (88%) nonoperative and operative obstetrical brachial plexus injuries managed between 1975 and 2001. RESULTS: Fifty-two percent of the nonoperative patients evaluated at an initial visit had an IR of 4 or 5, which represents very poor function by comparison to IR of 1 in the Eng scale, which represents almost no abnormality. The percentage of patients in this category (4-5) improved to 30% after follow-up visits. For the 16 operative cases, the initial and follow-up percentages of patients with IRs of 4 or 5 were 67% and 22%, respectively. Ultimately, 47% of the nonoperative patients achieved a grade 2 IR after follow-up compared with 17% of the operative patients. CONCLUSION: Using this selective approach at LSUHSC, in which the operative rate was 9%, acceptable outcomes were obtained both in patients not having surgery and also in those having surgical intervention.

Intraoperative nerve action potential recordings: technical considerations, problems, and pitfalls.

OBJECTIVE: The purpose of this article is to provide our experience with intraoperative nerve action potential (NAP) recordings. In particular, we focus on a discussion of the technical considerations of intraoperative NAP with emphasis on identifying and remedying problems and pitfalls. METHODS: We report, perhaps, the largest operative series of peripheral nerve lesions in continuity with intraoperative NAP recording derived from 1736 patients with 3459 lesions in continuity with operative outcomes. We pay special attention to patients for whom we felt that NAP recordings were either difficult or misleading. RESULTS: A positive NAP across a lesion resulting in neurolysis gave grade 3 or better function using the Louisiana State University Health Science Center grading system in 94.7% of neural elements. Differential fascicular recordings resulted in split repair in 62 nerves with recovery in 58. The absence of an NAP correlated histologically with a neurotmetic lesion. With resultant repair, 1111 of 1975 nerves recovered to grade 3 or better. CONCLUSION: Visual inspection of a nerve lesion in continuity can be misleading. Although there is no "head-to-head" comparison of our data with data obtained without the use of intraoperative NAP recordings, we feel strongly that with experience and knowledge of the problems and pitfalls regarding intraoperative recording techniques, one may take advantage of the great benefits of this very useful and informative surgical tool.

Timing for brachial plexus injury: a personal experience.

This article is a presentation of personal experience and resultant views by the author on the timing of surgery for nerve injury, especially that for brachial plexus injuries. The author presents arguments for early and delayed surgery based on the type of injury encountered and examines how early nerve repair on all might preclude spontaneous recovery. On the other hand, neglect of repair or greatly delayed repair is also deleterious because many useful outcomes can be gained by a well timed nerve repair or transfer. This is part of a Point-Counterpoint discussion with Dr. Rolfe Birch's presentation of "The London Experience."

Submuscular transposition of the ulnar nerve for the treatment of cubital tunnel syndrome.

THE ULNAR NERVE is compressed at the cubical notch in patients with cubital tunnel syndrome. To definitively alleviate this compression, the nerve can be transposed under the pronator teres and flexor carpi ulnaris muscles. This procedure is also known as medianization of the ulnar nerve because it then courses parallel to the median nerve. In the current article the procedure is described in a step-by-step fashion.

Nerve surgery: where we are and where we might go.

Operative surgery remains the major therapeutic modality for most serious nerve injuries, entrapments, and many nerve tumors. This article highlights the advancements that have been made in nerve surgery since World War I, including nerve action potential recording, MRI, timing of repair, grafts, tubes, end-to-side repair, replantation of plexus roots, transfers, entrapments, and tumors. Future needs in nerve surgery are identified, including the development of new methodologies and additional research and outcome studies.