Evidence Of Acute Denervation Research Articles

EP.111Identification of novel biallelic mutations in SPTBN4 in a child with NEDHND featuring a spinal muscular atrophy phenotype

Neurodevelopmental disorder with hypotonia, neuropathy, and deafness (NEDHND, OMIM: #617519) is an autosomal recessive disorder caused by homozygous or compound heterozygous mutations in the SPTBN4. Mutations in SPTBN4 disrupt cytoskeletal machinery that control proper localization of ion channels and function of axonal domains, generating severe neurological dysfunction. Recently, recessive mutations in human SPTBN4 have been described in 7 patients manifesting with severe hypotonia, developmental delay and mixed neuropathic and myopathic features, with central deafness and severe epilepsy in some cases. Here we report a six-year-old Chilean patient with a phenotype characterized by severe early-onset hypotonia, areflexia, proximal and distal weakness with an axonal motor neuropathy and evidence of acute denervation by EMG. At first evaluation at ten months of age, she presented as a spinal muscular atrophy phenotype and negative result for SMN1 deletion. Subsequently, a muscle biopsy showed neurogenic type grouping. The clinical evolution was characterized by global developmental delay, absent speech, deafness, progressive swallowing and respiratory difficulties. A tracheostomy and gastrostomy were indicated. Later in her evolution, appearance of severe generalized EEG epileptic abnormalities and absence of manifest clinical seizures were noted. A specific motor neuron diseases panel failed to find any mutation, and trio whole exome sequencing identified an apparent homozygous single base pair duplication in the SPTBN4 in the proband; this variant was also detected as heterozygous in the patient's father but was not detected in the patient's mother. However, a deletion involving multiple exons of the SPTBN4, which overlaps this variant, was identified in the proband and in the patient's mother, indicating that the two variants are in trans in the proband. This is the first multi-exon deletion that has been reported in the SPTBN4 to date. Additionally, this case highlights the early predominant motor axonal involvement in this patient manifesting as severe hypotonia and areflexia similar to others non-5q SMA patients, and the consecutive appearance of another feature in the clinical evolution as the auditory neuropathy and epileptic activity in EEG as key elements to suspect SPTBN4 mutation.

Evaluation of Conventional Subciliary Incision Used in Blepharoplasty: Preoperative and Postoperative Videography and Electromyography Findings

The purpose of this study was to evaluate the innervation and function of the orbicularis oculi area clinically, with video imaging, and electrically, with electromyography, before and after lower-eyelid blepharoplasty using a conventional subciliary incision. Nine patients (18 eyes) were studied before and 4 to 12 weeks after lower-eyelid blepharoplasty. Video imaging documented clinical changes in involuntary (blink) and voluntary (squeeze and squint) eyelid function as well as resting lid position and tone. Electromyography was performed using concentric needle electrodes (25 mm in length, 0.03 mm in diameter) placed in the lateral and medial subciliary orbicularis oculi. A total of 36 sites in nine patients (four sites per patient) were studied. Acute denervation was identified by the presence of fasciculation; fibrillation potentials; insertional activity; sharp waves; and grade based on standard electromyography techniques. All patients underwent lower-eyelid blepharoplasty with a subciliary incision, skin-muscle flap and canthal anchoring with canthopexy or cantholysis, and canthoplasty. Video imaging of the lower eyelid before and after blepharoplasty showed evidence of eyelid malposition or abnormal voluntary or involuntary orbicularis oculi muscle function. There was no evidence of acute denervation in 34 of 36 sites (94 percent). Two patients had abnormal fasciculation in the left lateral position on two of 36 sites (6 percent). Thirty-three weeks postoperatively, one patient was retested and a normal electromyography result was obtained. This study demonstrated that lower-lid malposition or abnormal function after lower-lid blepharoplasty cannot be explained by denervation of the zygomatic branch of the facial nerve. Any acute or residual denervation seen in the subciliary orbicularis is not clinically significant. The importance of lower-lid support and canthal anchoring cannot be emphasized enough in preventing lower-lid malposition. Blepharoplasty is a challenging procedure that requires careful preoperative planning, intraoperative reassessment, and meticulous surgical technique to optimize facial rejuvenation and patient safety.

Cauda Equina and Conus Medullaris Syndrome in Sarcoidosis

Neurosarcoidosis is a rare manifestation of sarcoidosis. Involvement of the nervous system in sarcoidosis can range from peripheral or cranial neuropathy to central nervous system disease. Cauda equina sarcoidosis is distinctly rare. The authors present a 58-year-old patient with systemic sarcoidosis who developed cauda equina and conus medullaris syndrome. Seventeen previous published cases of cauda equina sarcoidosis are reviewed. The history of systemic sarcoidosis, cerebrospinal fluid characteristics of lymphocytic pleocytosis with elevated protein, and evidence of acute denervation by needle electromyography are helpful in the diagnosis of this condition. Early diagnosis and treatment of cauda equina sarcoidosis usually provide a rapid recovery and yield a good prognosis. Although rare, sarcoidosis should be considered in the differential diagnosis of cauda equina syndrome, particularly in patients with unclear etiology.

BUTTOCK PAIN - HOCKEY PLAYER

HISTORY A 27 y/o professional hockey player presented with a one year hx of left buttock pain after being slashed by a hockey stick in the middle of the left posterior thigh. He began having low grade aching buttock pain. He could not move for a short period of time and then began to resume progressive activities. After a month he was able to do cycling but with side-to-side maneuvers he had severe buttock and hamstring pain. An MRI of his hip area was unremarkable. Massages only provided transient relief. He is having increased difficulty sitting on hard surfaces. He has a sense of tightness in the buttocks area. Despite the pain he has continued to play but states that it has affected his athletic performance. He has slight degree of lower back pain. He has numbness over the back of the left thigh and lateral aspect of the leg and foot. Some disc bulges have been reported on a previous MRI of the lumbo-sacral area prior to the injury. PHYSICAL EXAMINATION Full ROM of the back. Non-tender over the spinous processes of the lower back. Straight leg raising is negative but he lacks 15 degrees on the left. Has a sense of tightness in the ischial area. With the hip flexed to 90 degrees and progressive internal rotation he has reproduction of his symptoms. There is pain with palpation over the proximal lateral ischium. No clear weakness on examination of the left leg. No wasting or fasciculations noted. Decreased pin-prick over the lateral posterior thigh and the lateral leg and foot. Reflexes present and symmetrical. Normal gait. Increased tone in the left hamstring group. DIFFERENTIAL DIAGNOSIS Disc herniation and L5 radiculopathy/sciatica. Piriformis syndrome. Proximal hamstring syndrome. Hamstring tendonitis. TESTS AND RESULTS NCS of the left leg:-delay in the tibial motor F-wave latency response-unable to obtain sural sensory response-normal peroneal motor response EMG of the left leg, buttock, and lumbo-sacral paraspinal area: -normal -no evidence of acute denervation or advanced chronic denervation/reinnervation anywhere MRI Lumbar: -L3-L5 levels demonstrate mild spondylosis with disc narrowing, desiccation, and diffuse concentric annulus bulge without new progressive focal or lateralizing disc extrusion or limiting stenosis of the central spinal canal or L3,L4 neural foramina -L5-S1 level demonstrates mild spondylosis with disc narrowing, desiccation, and diffuse concentric annulus bulge. There is mild broad based right paracentral and latera/intraforminal disc protrusion with mild impression on the exiting right S1 nerve root and right L5 neural foramen. FINAL/WORKING DIAGNOSIS Proximal hamstring syndrome. TREATMENT AND OUTCOMES Proximal hamstring release, sciatic nerve decompression, and Alloderm tissue wrapped around sciatic nerve to prevent scar tissue from forming. 2 weeks after surgery started gentle progressive ROM, gentle concentric and eccentric hamstring exercises, and water therapeutic exercises. At 6 weeks can straight leg raise beyond 90 degrees without pain over the ischium, no numbness or tingling down the left leg. At 9 weeks unable to sprint, has weakness but no sharp pain, taking cox-2 inhibitor, has returned to skating but no scrimmage yet, sitting tolerance improved. Return to full NHL level play antioriated.

Predicting acute denervation in carpal tunnel syndrome

Objective: To determine which nerve conduction parameters can predict the presence of acute denervation in carpal tunnel syndrome. Setting: The electrodiagnostic laboratories of a hospital and a county hospital district. Design: A retrospective review. Patients: A total of 1,590 consecutive cases from January 1992 to June 1996, diagnosed as having median neuropathy at the wrist. Main Outcome Measures: Evidence of acute denervation on needle electromyography of the abductor pollicis brevis and its relationship to patient age, gender, and parameters obtained from nerve conduction studies, including median sensory latency and amplitude, and median motor latency and amplitude. Results: Logistic regression analysis identified gender, median motor latency, and median motor amplitude (all p ≤ .008) as contributing to the prediction of denervation. Needle examination of the cases with a median motor amplitude <7mV detected 95.3% ( 141 148 ) of all cases with denervation and could have spared 52% ( 708 1,362 ) of the population from a needle examination of the abductor pollicis brevis. Conclusion: The median motor amplitude can predict the presence of acute denervation in the thenar muscles in median neuropathy at the wrist and possibly eliminate a painful needle examination of the median-innervated thenar muscles in over 50% of the cases.

Congenital hypomyelinating neuropathy: A reversible case

A boy was born at 39 weeks gestation with severe weakness and hypotonia, fractured femurs, poor suck and swallow, and absent deep tendon reflexes. Electrodiagnostic studies revealed marked slowing of motor nerve conduction velocities and normal muscle electrical activity with no evidence of acute denervation. Muscle biopsy showed mild type 2 fiber predominance, and sural nerve biopsy revealed large axons without myelin, and axons with insufficient amount of myelin for their diameter. There was no evidence of inflammation or demyelination. Gradual clinical improvement in tone and strength occurred in a cephalocaudal direction. By 4 months, motor nerve conduction velocities and clinical examination were normal apart from absent deep tendon reflexes. On review at 19 months, motor development and neurological examination were completely normal. Pathogenesis of this reversible pathologically documented case of congenital hypomyelinating neuropathy is unclear. No evidence was found for an inflammatory, toxic, metabolic, or demyelinating cause. Abnormal expression of a developmental gene, as in reversible cytochrome oxidase deficiency, may be a cause of this neuropathy.