Intrapartum maternal lumbosacral plexopathy

There are many conflicting theories regarding the mechanism and prognosis of acute foot drop during labor. We report seven women who had arrested labor and foot drop. Six had short stature and one had a large newborn. All had weakness of ankle dorsiflexion, eversion, and inversion, and sensory loss in the L-5 dermatome. Superficial peroneal sensory nerve action potentials (SNAPs) were small or absent in six patients, and the sural SNAP was attenuated in one. Peroneal compound muscle action potential (CMAP) amplitude (recording from extensor digitorum brevis) was low in five, whereas the tibial CMAP was normal in all patients. Peroneal CMAP amplitude (recording from the tibialis anterior) was normal in three and small in three. Needle electromyography revealed decreased recruitment and fibrillation potentials in L-5-innervated muscles, mostly below the knee. We conclude that intrapartum foot drop occurs mostly in short women and is caused by lumbosacral trunk compression by the fetal head at the pelvic brim. The primary pathology is predominantly demyelination and recovery is complete in up to 5 months.     

Brachial plexopathies: classification, causes, and consequences

The brachial plexus, which is the most complex structure of the peripheral nervous system, supplies most of the upper extremity and shoulder. The high incidence of brachial plexopathies reflects its vulnerability to trauma and the tendency of disorders involving adjacent structures to affect it secondarily. The combination of anatomic, pathophysiologic, and neuromuscular knowledge with detailed clinical and ancillary study evaluations provides diagnostic and prognostic information that is important to clinical management. Since most brachial plexus disorders do not involve the entire brachial plexus but, rather, show a regional predilection, a regional approach to assessment of plexopathies is necessary.     

Acute heroin-related neuropathy

Heroin-related peripheral nervous injury has scarcely been reported, mostly as compressive neuropathy. Rarely, other types of peripheral nervous system (PNS) injury have been recognized, such as plexopathy, polyradiculopathy, mononeuropathy, and rhabdomyolysis. These complications are usually not related to local trauma, but the nature of nerve injury remains unknown. Immunologic mechanisms have been proposed, although generally there is no laboratory evidence of inflammation and usually there is no improvement following steroid therapy. We describe six patients who developed acute PNS injury following intravenous or intranasal heroin self-administration with no evidence of compression injury or inflammation. Four patients had plexopathy (two lumbosacral and two brachial), and two had symmetric distal axonal sensorimotor neuropathy affecting the lower extremities. Of the six patients, five had concomitant rhabdomyolysis (creatine kinase, CK: 5,000-100,000 U/l) and one patient with brachial plexopathy had normal CK levels. The neurological deficit was noticed 3-36 h after heroin administration. Electromyography in five patients was consistent with sensorimotor axonal loss either confined to the affected plexus or with a diffuse distribution in the legs in the two patients with neuropathy. We propose that a toxic mechanism may be responsible for non-compression cases of acute neuropathy following heroin abuse.     

Pure motor Herpes Zoster induced brachial plexopathy

Brachial plexus neuritis in the presence of herpes zoster infection is uncommon. Motor involvement is probably due to the spreading of inflammation from the dorsal root ganglia to the ventral roots and may be more extensive than the affected dermatomes. We present a case of herpes zoster brachial plexopathy with pure motor involvement both clinically and electrophysiologically.     

Backpack palsy and other brachial plexus neuropathies in the military population

Brachial plexus neuropathy is often seen in the military population, especially due to pressure (backpack palsy, BPP) or idiopathic (neuralgic amyotrophy, NA). We aimed to gain insight in the disease characteristics of soldiers with brachial plexus neuropathies in the Dutch military population and to compare disease characteristics between patients with BPP and NA. In this retrospective chart review study we aimed to include all patients with brachial plexus neuropathy, who presented in the Joint Military Hospital between 1 January, 2011 and 31 December, 2016. We calculated the incidence of NA and BPP and Chi‐square tests or Student t tests were performed for differences in patient characteristics between NA and BPP. We included 127 patients, 63 with BPP, 45 with NA, 10 with traumatic brachial plexus neuropathy, and 9 with other plexopathy. The incidence of brachial plexus neuropathy was 50/100 000 person years overall, 25/100 000 person years for BPP, and 18/100 000 person years for NA. Patients in the BPP group differed from the NA with regard to pain (BPP 41% vs NA 93%, P = .000), atrophy (13% BPP vs 29% NA, P = .049), and sensory symptoms (83% BPP vs 44% NA, P = .000). In the BPP group 90% had incomplete recovery and in the NA group 78%. Our study showed a high incidence of BPP and NA in the military population and suggests recovery is not so benevolent as previously thought. Future research is necessary to improve insight and outcome of military patients with brachial plexus neuropathies.     

Lead poisoning during heroin addiction

We describe the case of a young man addicted to heroin with the clinical pattern of symmetrical brachial neuropathy, without other neurological involvement. Lead poisoning was detected and chelating therapy induced a marked improvement of the clinical symptoms. The possible toxic effect of heavy metals in the pathogenesis of brachial and lumbar plexopathies during heroin addiction has previously been suggested by other authors, but never detected.

---

Sommario Viene descritto il caso di un giovane paziente che ha presentato una neuropatia brachiale simmetrica, senza altri coinvolgimenti neurologici, in concomitanza con l'uso di eroina. In questo paziente è stata evidenziata una intossicazione da piombo e il trattamento chelante ha determinato un notevole miglioramento del quadro clinico. L'effetto tossico dei metalli pesanti nella patogenesi delle plessopatie brachiali e lombari nei soggetti eroinomani è già stata prospettata da altri Autori, ma mai dimostrata.

     

Acute neuropathies after peripheral blood stem cell and bone marrow transplantation

Neuromuscular complications are not uncommon after bone marrow and stem cell transplantation, especially in patients with allogeneic transplantations and graft-versus-host disease. The pathogenesis of these complications remains unclear, but the changes in immune modulation that occur after transplantation are likely to play a key role. We describe 4 patients who developed brachial plexopathy (3 cases) or multiple lumbosacral radiculopathies (1 case) between 5 days and 4 months after autologous peripheral blood stem cell (3 cases) or allogeneic bone marrow transplantation without evidence of graft-versus-host disease (1 case). Infectious, tumor-related, toxic, and metabolic causes were excluded in all cases. Recovery was limited in two cases and nearly complete in the other two patients. Brachial plexopathies and polyradiculopathies are potential complications of peripheral blood stem cell and bone marrow transplantation. It is possible that these disorders may be the result of autoimmune phenomena directed against specific nerve antigens.     

Brachial plexopathy as a rare presenting manifestation of scorpion envenomation

We report a patient who experienced a rare manifestation of an acute, severe brachial plexopathy as the initial complication of scorpion (presumed Hemiscorpius lepturus species) envenomation. Features suggesting conduction block, due to either proximal demyelination or ion channel dysfunction, along with axonal loss were seen on serial electrophysiological studies. Possible mechanisms of the brachial plexopathy include direct compression from tissue edema or a toxic effect on the membrane channels along the nerve.     

Pitfalls in the electrodiagnostic studies of sacral plexopathies

This retrospective review characterizes the electrodiagnostic (EDX) features and etiologies of sacral plexopathies (SPs) and discusses difficulties in their identification. The EDX findings of 171 clinically suspected SPs were reviewed using the following criteria: reduced/absent sensory nerve action potentials (SNAPs) of the sural or superficial peroneal nerve, denervation of plexus-innervated muscles, and the absence of paraspinal denervation. Sixty cases localized unequivocally to the sacral plexus. The majority were cancer-related, followed by traumatic, idiopathic, and iatrogenic causes. Final diagnoses in the remaining 111 cases were indeterminate. Lesions localized to either the plexus or L4-5, S1 roots in 52 cases, the plexus or sciatic nerve in 32 cases, and were equally compatible with an SP, sciatic neuropathy, or radiculopathy in 27 cases. Findings in the EDX evaluation of SPs are often complex and difficult to localize to a specific site due to multiple complicating factors. Frequently, SPs cannot be diagnosed definitively by EDX assessment alone.     

Clinical and electrodiagnostic findings in breast cancer patients with radiation-induced brachial plexus neuropathy

The clinical and neurophysiological characteristics of radiation-induced brachial plexopathy (RBP) were assessed in 79 breast cancer patients without signs of recurrent disease at least 60 months after radiotherapy (RT). Clinically, 35% (95% confidence limits: 25-47%) had RBP. Fifty percent (31-69%) had affection of the entire plexus, 18% (7-36%) of the upper trunk only, and 4% (1-18%) of the lower trunk. In 28% (14-48%), assessment of a definite level was not possible. In most, symptoms began during or immediately after RT, thus being without significant latency. Numbness or paresthesias (71%, 52-86%) and pain (43%, 25-62%) were the most prominent symptoms, while the most prominent objective signs were decreased or absent muscle stretch reflexes (93%, 77-99%) closely followed by sensory loss (82%, 64-93%) and weakness (71%, 52-86%). Neurophysiological investigations were carried out in 46 patients (58%). The most frequent abnormalities in patients with RBP were signs of chronic partial denervation with increased mean duration of individual motor unit potentials, and decreased amplitude of compound muscle and sensory action potentials. Nerve conduction velocities were normal.     

Detection of hereditary neuropathy with liability to pressure palsies among patients with acute painless mononeuropathy or plexopathy

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant disorder characterized by recurrent mononeuropathies or brachial plexopathies, commonly associated with a chromosome 17p11.2-12 deletion encompassing the peripheral myelin protein-22 (PMP22) gene. We tried to identify criteria distinguishing HNPP among patients with acute painless mononeuropathy/plexopathy. We investigated by pulsed-field gel electrophoresis the presence of the deletion in 27 patients with isolated or recurrent acute painless mononeuropathy or brachial plexopathy, and no obvious cause of neuropathy. Eight patients carried the deletion, whereas 19 had neither the deletion nor mutations in the PMP22 gene. Age at onset, presenting modality, precipitating events, and rate of recovery did not significantly differ in the two groups. Family history was informative for HNPP diagnosis in 3 cases only. HNPP patients more often showed recurrent episodes, brachial plexopathy, and clinical or electrophysiologic involvement of other nerves. Non-HNPP patients more frequently had peroneal palsy, recent weight loss, and normal electrophysiologic examination in other nerves. Signs of generalized neuropathy and evidence of disease in other family member are often subtle in HNPP and must be thoroughly investigated in patients with acute painless mononeuropathy/plexopathy. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21: 1686–1691, 1998.     

Lumbosacral Plexopathy, Complicating Rhabdomyolysis in a 57-Year-Old Man, Presented with Sudden Weakness in Both Legs

A 57-year-old man presented with weakness in both legs upon awakening after drinking. Magnetic resonance imaging (MRI) of the lumbar spine did not reveal any intraspinal abnormalities but MRI of the pelvis revealed lesions with abnormal intensities with heterogeneous contrast enhancement in both gluteal muscles. Serum creatine phosphokinase was markedly elevated. A diagnosis of lumbosacral plexopathy, complicating rhabdomyolysis was made. With supportive care he recovered well but mild weakness of the right ankle remained at 6 month-follow-up. Pelvic MRI is a helpful diagnostic tool in localizing rhabdomyolysis. Lumbosacral plexopathy should be included in the differential diagnosis of the such cases, presenting with sudden weakness of legs.     

Brachial plexopathy associated with Q fever: Case report and review of the literature

Neurologic manifestations of Q fever are predominantly central. We report the case of a 35‐year‐old man with recurrent fever and motor and sensory deficits in the right C5, C6 territories. Electrophysiological findings were consistent with a right upper‐trunk brachial plexopathy or with suprascapular and axillary neuropathies. The patient had full resolution of neurologic symptoms with antibiotic treatment. The association of brachial plexopathy with Q fever infection, described in other rare instances, may merit consideration in individual cases, depending on clinical context. Muscle Nerve 38: 1644–1648, 2008     

Isolated amyloidosis presenting with lumbosacral radiculoplexopathy: description of two cases and pathogenic review

In this study, we present two cases of infiltrative, localized amyloidosis involving lumbosacral root and plexus, e.g., isolated amyloidomas. Rare and poorly understood amyloidomas may occur in both neurologic and non-neurologic tissues. The described cases emphasize potential for localized peripheral amyloidomas: (1) potential for associated lambda light chain lymphoplasmacytic lymphoma association; (2) e isolated amyloidosis without evidence for systemic plasma cell dyscrasia; (3) features suggestive of potential pathogenesis; and (4) discussion of treatment options including immunotherapy and resection. The limited literature and experience among other cases is described.     

Motor conduction studies for prognostic assessment of obstetrical plexopathy

Early prognostic assessment of obstetrical brachial plexopathies (OBP) would facilitate rational selection of infants for brachial plexus surgery. We performed bilateral motor nerve conduction studies (MNCS) of axillary, musculocutaneous, radial, median, and ulnar nerves in 33 babies (age 10-60 days) with OBP in order to compare the amplitude of compound muscle action potentials (CMAPs). All babies were followed up until 6 months of age and the outcome was classified according to muscle strength and arm function. A CMAP amplitude reduction of more than 90%, compared to the unaffected side, predicted severe weakness of the corresponding root level (p < 0.01). Our results indicate that MNCS are a useful tool for very early prognostic assessment of OBP.