Camptocormia in Parkinson's Disease

Abstract & Commentary

By Michael Rubin, MD, Professor of Clinical Neurology, Weill Cornell Medical College. Dr. Rubin reports no financial relationships relevant to this field of study.

Synopsis: Camptocormia may occur in a wide variety of central and peripheral nervous system disorders, including primary muscle disease.

Source: Margraf NG, et al. Camptocormia in idiopathic Parkinson's disease: A focal myopathy of the paravertebral muscles. Mov Disord (wiley.com. DOI: 10.1002/mds.22780).

Camptocormia (CC), abnormal trunk flexion appearing when standing or walking and disappearing when supine, has been attributed to normal aging, and a wide variety if disorders, including hysteria, spondylitis, neuromuscular disorders extending from the anterior horn cell to muscle including amyotrophic lateral sclerosis, myasthenia gravis, polymyositis, inclusion body myositis, and nemaline myopathy, to paraneoplasia, and valproate toxicity. Seen commonly in movement disorders, particularly Parkinson's disease (PD), it has been ascribed to axial dystonia.1 Current evidence suggests that camptocormia in idiopathic PD may be myopathic in origin.

Between 2004 and 2007, 15 PD patients with CC and 15 without CC underwent comparison study encompassing detailed neurological examination including the Unified Parkinson's Disease Rating Scale, electromyographic (EMG) study, cranial scan, serum creatine kinase measurement, magnetic resonance imaging of paravertebral muscles of the entire spinal axis with and without gadolinium, and biopsy of paravertebral muscles, the latter compared to age-matched autopsies, to explore the etiology of CC in PD. British Parkinson's Disease Society Brain Bank criteria were used to diagnose PD. Radiographic studies were evaluated by blinded neuro-radiologists. Statistical analysis included the Mann-Whitney U-test and Spearman's rank correlation coefficient.

CC occurred almost exclusively in advanced PD, occurring a median of 9.0 years after PD diagnosis, at a median of 64 years of age, with a median angle of 60° forward flexion, and equally in men and women. CC was more severe the younger the age of PD onset. Most patients (n = 13) bent forward from the onset, with 12 also reporting lateral flexion. Two began with lateral flexion, later developing anteroflexion, and no correlation was found between side of PD onset and side of CC onset. CC was also present in the seated position in 10. Back pain was reported in 13 CC patients but it predated CC in eight. No CC patient demonstrated dystonic abdominal musculature. Back pain, additional back diseases, and less dopa-sensitivity were seen significantly more in CC-PD patients compared to PD patients without CC.

Among CC patients, CK was elevated in nine, and EMG demonstrated small polyphasic myopathic motor unit potentials in eight. MRI was abnormal in all CC patients, demonstrating either bilateral asymmetrical muscle edema, which enhanced with GAD, in those with disease duration less than 12 months, or localized or asymmetrical muscle atrophy and fatty degeneration, in those with disease duration greater than 30 months. Paravertebral muscle biopsy in 12 CC patients, obtained from the most affected muscles based on MRI scan, was myopathic in all, with increased connective tissue, internal nuclei, variability of fiber size, variable expression of atrophic and hypertrophic fibers, and fiber splitting. Myopathic EMG, MRI, or biopsy abnormalities were not seen in the non-CC-PD group. Corsets, increased carbidopa/levodopa dosage, and oral corticosteroid medication were of no benefit. CC in PD appears to be a focal progressive myopathy of the paravertebral muscles.

Commentary

Protirelin tartrate (PT, thyrotropin-releasing hormone tartrate), believed to act by regulating excitatory amino acids or glucose metabolism, has been used, primarily in Japan, for the treatment of a variety of ataxic disorders including hereditary spinocerebellar degeneration and multiple system atrophy (MSA). Administered to a 68-year-old woman with camptocormia associated with MSA, camptocormia was significantly improved by the second day of treatment.2 At Weill Cornell Medical Center, an 80-year-old man with camptocormia and found to have 3.9 5 3.8 5 3.9 cm dural-based extra-axial meningioma within the right frontal region with extensive surrounding vasogenic edema, resulting in approximately 6 mm of right-to-left subfalcine herniation. Surgical resection of the tumor resolved the camptocormia. Camptocormia has a broad differential and both supratentorial and infratentorial causes must be pursued.

References

1. Bloch F, et al. Parkinson's disease with camptocormia. J Neurol Neurosurg Psychiatry 2006;77:1223–1228.

2. Takei A, et al. Amelioration of subacute camptocormia in multiple system atrophy by protirelin tartrate. Movement Dis 2009:24;2022-2023