Severe Adult-Onset Non-Dystrophic Myotonia With Apnea and Laryngospasm Due to Digenic Inheritance of and Variants: A Case Report.

Objectives: To report a case of adult-onset non-dystrophic myotonia complicated by recurrent episodes of laryngospasm.

Methods: The patient is a 35-year-old man who was admitted to our hospital for recurrent episodes of apnea requiring endotracheal intubation with mechanical ventilation. He underwent extensive evaluation, including EMG, laryngoscopy, muscle biopsy, and genetic testing, which revealed a diagnosis of non-dystrophic myotonia.

Investigating Late-Onset Pompe Prevalence in Neuromuscular Medicine Academic Practices: The IPaNeMA Study.

Background And Objectives: We investigated the prevalence of late-onset Pompe disease (LOPD) in patients presenting to 13 academic, tertiary neuromuscular practices in the United States and Canada.

Methods: All successive patients presenting with proximal muscle weakness or isolated hyperCKemia and/or neck muscle weakness to these 13 centers were invited to participate in the study. Whole blood was tested for acid alpha-glucosidase (GAA) assay through the fluorometric method, and all cases with enzyme levels of ≤10 pmoL/punch/h were reflexed to molecular testing for mutations in the GAA gene.

Randomized, placebo-controlled trials of dichlorphenamide in periodic paralysis.

Objective: To determine the short-term and long-term effects of dichlorphenamide (DCP) on attack frequency and quality of life in hyperkalemic (HYP) and hypokalemic (HOP) periodic paralysis.

Methods: Two multicenter randomized, double-blind, placebo-controlled trials lasted 9 weeks (Class I evidence), followed by a 1-year extension phase in which all participants received DCP. Forty-four HOP and 21 HYP participants participated.

Cervical Myelopathy Caused by Injections into the Neck.

Three cases of longitudinally extensive cervical myelopathies temporally associated with neck injections are presented. The spinal cord injury was similar radiographically, despite a number of different needle approaches and substances injected. In recent years, there have been reports of an acute cervical myelopathy immediately following an injection procedure in the neck.

Quantitative ultrasound of denervated hand muscles.

Introduction: Presentations to the neuromuscular clinic commonly involve hand muscle denervation, but few studies have evaluated hand muscle ultrasound.

Methods: Ultrasound studies of abductor pollicis brevis, first dorsal interosseous, and abductor digit minimi were prospectively performed in a cohort of 34 patients (77 muscles) with electromyography (EMG)-confirmed denervation, compared with 58 healthy control subjects.

Results: In control subjects, muscle thickness was highly reproducible [intraclass correlation coefficient (ICC) = 0.

A comparison of ultrasonographic and electrophysiologic 'inching' in ulnar neuropathy at the elbow.

Objective: The present study aimed to clarify the relationship between structural ulnar nerve changes and electrophysiological nerve dysfunction in patients with ulnar neuropathy at the elbow (UNE).

Methods: High-resolution ultrasonography of the ulnar nerve was performed on 17 limbs with clinically and electrophysiologically confirmed UNE, and 52 control subjects at four standardised sites proximal and distal to the medial epicondyle (P2, P1, D1, D2), corresponding to segments of ulnar short-segment nerve conduction studies ("inching studies").

Results: Ulnar nerve cross-sectional area (CSA) and hypoechoic fraction were significantly increased in patients with UNE immediately distal (D1) and proximal (P1) to the medial epicondyle (p<0.

Transient hyperckemia in the setting of neuromyelitis optica (NMO).

Introduction: Neuromyelitis optica (NMO) is characterized by inflammatory demyelinating lesions of the spinal cord and optic nerves from an autoimmune response against water channel aquaporin-4 (AQP4). We report 2 patients with transient hyperCKemia associated with NMO suggesting possible skeletal muscle damage.

Methods: Patient 1 was a 72-year-old man who presented with muscle soreness and elevated serum creatine kinase (CK) preceding an initial attack of NMO.

Sonographic diagnosis of true neurogenic thoracic outlet syndrome.

A 32-year-old woman presented with a 5-year history of left shoulder pain, medial hand and forearm numbness, and progressive hand weakness and atrophy. Electrodiagnostic studies were characteristic of true neurogenic thoracic outlet syndrome, and a chest X-ray showed bilateral elongated C7 transverse processes. High-resolution ultrasound studies revealed compression of the left lower trunk (LT) between a fibrous band and artery (figure, A).

Dual reinnervation of biceps muscle after side-to-side anastomosis of an intact median nerve and a damaged musculocutaneous nerve.

Traumatic peripheral nerve injury can lead to significant long-term disability for previously healthy persons. Damaged nerve trunks have been traditionally repaired using cable grafts, but nerve transfer or neurotization procedures have become increasingly popular because the axonal regrowth distances are much shorter. These techniques sacrifice the existing nerve pathway, so muscle reinnervation depends entirely on the success of the repair.

Electrical brain events associated with awareness of errors.

Objective: The neurophysiological correlates of mental activity and awareness are important to define, as they permit the objective study of these psychological phenomena.

Methods: In a choice reaction task, subjects were asked to respond to tone pips by extending their fingers and to make non-semantic vocalizations as soon as they became aware of any errors.

Results: In motor response-synchronized averages of instances in which subjects were aware of making errors, a biphasic cerebral potential occurred over the frontocentral scalp region 170 ms after the incorrect motor response and about 500 ms prior to any vocalization.