David G. Kline
Jacob Schwarz and Allan J. Belzberg
✓ Approximately 100 cases of segmental neurofibromatosis (NF5) have been reported in the recent literature. Patients with NF5 present with café-au-lait macules, freckles, and/or neurofibromas limited to one or adjacent dermatomes. Neurofibromas arising in NF5 have been uniformly considered to be benign; patients were thought to have an excellent prognosis without the risk of developing malignant peripheral nerve sheath tumors (PNSTs), which are characteristic in patients with the generalized form of this disease, von Recklinghausen's NF. In this report the authors detail the first observations of malignant PNSTs in two patients with NF5. Indications for surgical removal of a neurofibroma in a patient with NF include pain, neurological impairment, compression of adjacent structures, cosmetic disfigurement, and rapid tumor growth suggestive of malignant degeneration. Surgical indications are similar for patients with NF5. All patients with neurofibromas should be considered at risk for malignant degeneration.
Courtney Pendleton, Allan J. Belzberg, Robert J. Spinner and Alfredo Quinones-Hinojosa
Harvey Cushing is widely regarded as one of the forefathers of neurosurgery, and is primarily associated with his work on intracranial pathology. However, he had a clinical and academic interest in peripheral nerve surgery. Through the courtesy of the Alan Mason Chesney Medical Archives, the surgical records of the Johns Hopkins Hospital from 1896 to 1912 were reviewed. The records of a single patient undergoing brachial plexus exploration and cervical rib resection were selected for detailed review. The operative report and accompanying illustrations demonstrate Cushing’s interest in adding approaches to the pathology of the brachial plexus to his operative armamentarium.
Michael J. Dorsi, Wesley Hsu and Allan J. Belzberg
The aim of this study was to estimate the prevalence of brachial plexus injury (BPI) in pediatric multitrauma patients.
The National Pediatric Trauma Registry was queried using the ICD-9 code 953.4, injury to brachial plexus, to identify cases of BPI. The patient demographics, mechanism of trauma, and associated ICD-9 diagnoses were analyzed.
Brachial plexus injuries were identified in 113 (0.1%) of the 103,434 injured children entered in the registry between April 1, 1985, and March 31, 2002. Sixty-nine patients (61%) were male. Injuries were most often caused by motor vehicle accidents involving passengers (36 cases [32%]) or pedestrians (19 cases [17%]). Head injuries were diagnosed in 47% of children and included concussion in 27%, intracranial bleeds in 21%, and skull fractures in 14%. Upper-extremity vascular injury occurred in 16%. The most common musculoskeletal injuries were fractures of the humerus (16%), ribs (16%), clavicle (13%), and scapula (11%). Spinal fractures occurred in 12% of patients, and spinal cord injury occurred in 4%. The Injury Severity Score ranged from 1 to 75, with a mean score of 10, and 6 patients (5%) died as a result of injuries sustained during a traumatic event.
Brachial plexus injuries occur in 0.1% of pediatric multitrauma patients. Motor vehicle accidents and pedestrians struck by a motor vehicle are the most common reasons for BPIs in this population. Common associated injuries include head injuries, upper-extremity vascular injuries, and fractures of the spine, humerus, ribs, scapula, and clavicle.
Allan J. Belzberg and Bruce I. Tranmer
✓ Traumatic atlanto-occipital dislocation is most often fatal. Consequently, there are only scattered case reports of patients surviving this injury, and treatment modalities are anecdotal and varied. The case of an 18-year-old woman who suffered an anterior atlanto-occipital dislocation as the result of a motor-vehicle accident is presented. Rigid posterior fixation and complete reduction of the dislocation were achieved using an anatomically contoured steel loop secured to the occiput and cervical vertebrae. The addition of cancellous bone to the graft afforded long-term stability. This operative treatment provided anatomical realignment of the dislocation and allowed early mobilization of the patient with the use of aggressive rehabilitation. Previously reported cases of patients surviving anterior atlanto-occipital dislocation are reviewed. The use of cervical traction, halo bracing, and operative stabilization is discussed.
Report of three cases and review of the literature
Richard E. Clatterbuck, Allan J. Belzberg and Thomas B. Ducker
✓ Although cervical disc herniation commonly requires surgical intervention, the intradural sequestration of a herniated cervical disc fragment is rare. In searching the world literature on this topic, the authors found six case reports. They report three new cases of intradural cervical disc herniation in which the patients presented with Brown—Séquard's syndrome and they review the literature. Although Brown—Séquard's syndrome is a rare clinical finding in extradural disc herniation, six of the nine patients with intradural cervical disc herniation (our cases and those from the literature) presented with symptoms of this syndrome. The remaining patients presented with para- or quadriparesis. This suggests that intradural disc herniation should be considered preoperatively in patients in whom there is magnetic resonance imaging or myelographic evidence of cervical disc herniation and Brown—Séquard's syndrome. In patients who underwent anterior cervical discectomy for the treatment of intradural cervical disc herniations, better outcomes were demonstrated than in those in whom posterior procedures were performed.
Allan J. Belzberg and James N. Campbell
✓ Division of a peripheral nerve produces an axotomy leading to neurite outgrowth from the proximal stump and wallerian degeneration in the distal stump. Because there is no longer a connection between the distal stump and neuronal cell bodies in the anterior spinal cord or dorsal root ganglion, it is assumed that no neurites should exist in the distal stump. The authors present the case of a patient who unexpectedly had a neuroma on the proximal end of the distal segment of a previously severed nerve. The lateral antebrachial cutaneous nerve had been surgically severed. Innervated by the radial nerve, a neuroma subsequently formed in the distal segment. Our hypothesis is that the proximal end of the distal portion of a severed nerve may be innervated by collateral sprouts of axons that branch at points of more distal plexus formation. This invokes a similar pathophysiology to the controversial notion of end-to-side nerve sprouting. Neuromas that develop on the “wrong side” of a nerve become an additional potential source of pain in patients with injured nerves.
Allan J. Belzberg, Michael J. Dorsi, Phillip B. Storm and John L. Moriarity
Object. Brachial plexus injuries (BPIs) are often devastating events that lead to upper-extremity paralysis, rendering the limb a painful extraneous appendage. Fortunately, there are several nerve repair techniques that provide restoration of some function. Although there is general agreement in the medical community concerning which patients may benefit from surgical intervention, the actual repair technique for a given lesion is less clear. The authors sought to identify and better define areas of agreement and disagreement among experienced peripheral nerve surgeons as to the management of BPIs.
Methods. The authors developed a detailed survey in two parts: one part addressing general issues related to BPI and the other presenting four clinical cases. The survey was mailed to 126 experienced peripheral nerve physicians and 49 (39%) participated in the study. The respondents represent 22 different countries and multiple surgical subspecialties. They performed a mean of 33 brachial plexus reconstructions annually. Areas of significant disagreement included the timing and indications for surgical intervention in birth-related palsy, treatment of neuroma-in-continuity, the best transfers to achieve elbow flexion and shoulder abduction, the use of intra- or extraplexal donors for motor neurotization, and the use of distal or proximal coaptation during nerve transfer.
Conclusions. Experienced peripheral nerve surgeons disagree in important ways as to the management of BPI. The decisions made by the various treating physicians underscore the many areas of disagreement regarding the treatment of BPI, including the diagnostic approach to defining the injury, timing of and indications for surgical intervention in birth-related palsy, the treatment of neuroma-in-continuity, the choice of nerve transfers to achieve elbow flexion and shoulder abduction, the use of intra- or extraplexal donors for neurotization, and the use of distal or proximal coaptation during nerve transfer.
Gang Wu, Allan Belzberg, Jessica Nance, Sergio Gutierrez-Hernandez, Eva K. Ritzl and Matthias Ringkamp
Intraoperative nerve action potential (NAP) recording is a useful tool for surgeons to guide decisions on surgical approaches during nerve repair surgeries. However, current methods remain technically challenging. In particular, stimulus artifacts that contaminate or mask the NAP and therefore impair the interpretation of the recording are a common problem. The authors’ goal was to improve intraoperative NAP recording techniques by revisiting the methods in an experimental setting.
First, NAPs were recorded from surgically exposed peripheral nerves in monkeys. For the authors to test their assumptions about observed artifacts, they then employed a simple model system. Finally, they applied their insights to clinical cases in the operating room.
In monkey peripheral nerve recordings, large stimulus artifacts obscured NAPs every time the nerve segment (length 3–5 cm) was lifted up from the surrounding tissue, and NAPs could not be recorded. Artifacts were suppressed, and NAPs emerged when “bridge grounding” was applied, and this allowed the NAPs to be recorded easily and reliably. Tests in a model system suggested that exaggerated stimulus artifacts and unmasking of NAPs by bridge grounding are related to a loop effect that is created by lifting the nerve. Consequently, clean NAPs were acquired in “nonlifting” recordings from monkey peripheral nerves. In clinical cases, bridge grounding efficiently unmasked intraoperative NAP recordings, validating the authors’ principal concept in the clinical setting and allowing effective neurophysiological testing in the operating room.
Technical challenges of intraoperative NAP recording are embedded in the current methods that recommend lifting the nerve from the tissue bed, thereby exaggerating stimulus artifacts by a loop effect. Better results can be achieved by performing nonlifting nerve recording or by applying bridge grounding. The authors not only tested their findings in an animal model but also applied them successfully in clinical practice.