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Multifocal motor neuropathy (MMN) is a progressive disorder producing asymmetrical weakness and muscle wasting. Case reports suggest that patients with MMN improve after cyclophosphamide therapy, but not after prednisone or plasmapheresis. Because MMN is likely to be immune mediated, we investigated the therapeutic response to human immune globulin (HIG) in an open, uncontrolled trial. Nine patients, ages 28 to 58 years, had chronic, progressive, asymmetrical, predominantly distal, limb weakness for 5 to 18 years. Sensation was normal, and reflexes were reduced asymmetrically. All had physiological evidence of multifocal motor demyelination with partial motor conduction block, and 7 had elevated serum titers of anti-GM1 IgM antibody. All patients were treated with HIG, 1.6 to 2.4 gm/kg, given intravenously over 3 to 5 days. Strength improved in all patients 3 to 10 days after treatment, with improvement peaking at 2 weeks and lasting for an average of 2 months. The range of functional improvement varied from dramatic to mild. The degree of partial motor conduction block was reduced, at least partially, in 7 of 8 patients. The serum anti-GM1 antibody titers did not change. Repeated courses of HIG resulted in similar improvements. We conclude that HIG may be an effective therapy for patients with MMN.

Preclinical investigations indicated that recombinant human ciliary neurotrophic factor (rhCNTF) may have potential as therapy for amyotrophic lateral sclerosis (ALS). We evaluated the safety and efficacy of rhCNTF in a prospective, double-blind, placebo-controlled trial in 570 patients with ALS. Patients were randomized to receive 0.5, 2, or 5 micrograms/kg/day rhCNTF, or placebo, for 6 months. The primary efficacy end point was the change from baseline to the last on-treatment value of a combination megascore for limb strength (maximum voluntary isometric contraction) and pulmonary function. Secondary end points included individual arm and leg megascores, pulmonary function tests, an activities-of-daily-living outcome measure, and survival. The four treatment groups were similar at baseline with respect to age, sex, disease duration, and muscle strength values. At all doses tested, rhCNTF had no beneficial effect on the primary or secondary end points. Certain adverse events, as follows, appeared to be dose related: injection site reactions, cough, asthenia, nausea, anorexia, weight loss, and increased salivation. There was an increased number of deaths at the highest dose level. rhCNTF had no beneficial effect on any measure of ALS progression. There were increased adverse events in the 5 micrograms/kg group and increased deaths.

Objective To examine the care of patients with ALS following the publication of the standardized recommendations for the management of patients with amyotrophic lateral sclerosis (ALS) published in 1999 by the American Academy of Neurology. Methods Specific aspects of ALS patient management have been evaluated serially using a national Amyotrophic Lateral Sclerosis Clinical Assessment, Research, and Education (ALS CARE) database to encourage compliance with these recommendations and to assure continuing quality improvement. Results The most recent analysis of 5,600 patients shows interesting epidemiological observations and treatment trends. Proper management of many ALS symptoms has increased substantially since the first publication of the guidelines, and awareness of pseudobulbar affect has increased. Other recommendations are underutilized: Only 9% undergo percutaneous endoscopic gastrostomy, although this procedure was recommended in 22% of patients; and noninvasive positive pressure ventilation was used by only 21% of patients despite being associated with improved 5-year survival rates. Interpretation This observational database has been a useful tool in monitoring compliance with the standard of care for patients with ALS and may have resulted in greater adherence to guidelines. Ann Neurol 2009;65 (suppl):S24–S28

Patients with cerebellar lesions and limb ataxia performed two types of continuous tracking tasks involving flexion and extension of the index finger. In both tasks, patients were provided cutaneous and proprioceptive cues, but visual feedback was given in the first task (visual tracking) and not in the second (arbitrarily termed proprioceptive tracking). Raw records and Fourier-analyzed power spectra were compared with results in normal controls. Harmonic distortion was determined for each task. In all patients, as well as normal subjects, tracking performance was markedly improved and harmonic distortion substantially reduced during proprioceptive tracking. This surprising finding may result from a much shorter feedback loop for proprioceptive stimuli compared to visual stimuli. The tracking records, power spectra analysis, and determination of harmonic distortion provide both qualitative and quantitative data in patients with dyssynergia.

Twelve patients with progressive cubital tunnel syndrome were treated with simple decompression of the ulnar nerve. The clinical and electrophysiological responses to treatment are described.

The cubital tunnel syndrome is a subgroup of ulnar neuropathies arising at the elbow, with nerve entrapment under the aponeurosis connecting the two heads of the flexor carpi ulnaris muscle. To separate this condition more clearly from tardy ulnar palsy, the clinical and electrophysiological features of 9 patients are presented, 6 of whom had the syndrome bilaterally. There was no history of trauma and no clinical or roentgenographic evidence of joint deformity in any of the patients. In 9 of the 15 ulnar nerves, abnormal conduction was localized to the level of the cubital tunnel (1.5 to 3.5 cm distal to the medial epicondyle). The findings were confirmed intraoperatively in 7 patients and corresponded to a tight band compressing the ulnar nerve and causing narrowing at the cubital tunnel with swelling proximally. This syndrome represents a common and distinct subgroup of ulnar neuropathies at the elbow.

The mechanical and electrical properties of the partially denervated first dorsal interosseous muscle were measured in 14 patients and 14 normal control subjects. The following variables were studied during isometric contraction: maximum voluntary contraction; maximum rate of rise of tension in a rapid voluntary contraction; amplitude, rate of rise, time to peak, and duration of peak of the compound muscle action potential; twitch force, maximum rate of rise, contraction time, and half-relaxation time; and tetanic (50 Hz) force, rate of rise, and tetanus/twitch ratio. The force produced during repetitive stimulation of the ulnar nerve at 10, 20, 50, and 100 impulses per second was also analyzed. The major findings were: (1) decreased load bearing (voluntary contraction, twitch, and tetanus), (2) prolonged twitch contraction times and half-relaxation times, (3) decreased tetanus/twitch ratio, and (4) preserved rate of rise of tension.

With the exception of the large series of adult-onset hereditary distal myopathy from Sweden, few cases of primary muscle disease with a definite distal predilection have been published. We report 3 sporadic cases of distal myopathy with the following features: (1) early adult onset (26 to 33 years); (2) slowly progressive weakness affecting first the distal leg muscles and later the arms; (3) marked elevation of creatine phosphokinase (more than 10 times the normal value); and (4) electromyographic and histological evidence of myopathy in distal muscles. The differential diagnosis is discussed and other reported cases are reviewed. The differences between hereditary cases reported by others and the sporadic cases reported here form the basis for a tentative subclassification of this syndrome.