Myopathy causing camptocormia in idiopathic Parkinson's disease: A multidisciplinary approach

Abstract

Extreme forward flexion of the spine, named camptocormia (CC), and head drop syndrome (HD) may be among the most disabling symptoms in Parkinson's disease (PD). This study aims to eludicate the etiology of PD-associated CC and HD via a multidisciplinary approach (clinical examination, electromyography, MRI, genetic analysis, muscle morphology) centering on the histology of the paraspinal muscles. We studied 17 patients with the clinical diagnosis of PD and CC or head drop syndrome and six controls. We performed muscle biopsies of paraspinal muscles and deep neck extensor muscles. Mean age at onset of postural abnormality was 66 years and mean latency between onset of parkinsonian symptoms to first signs of CC or head drop was 7 years. The electromyogram of paraspinal muscles was abnormal in 13-14 patients. Histopathology revealed chronic myopathic changes in 14 of 17 biopsies, consisting of abnormal variation in fiber size, increase in internal nuclei, and increase in connective tissue, myofibrillar disarray and similarities to protein surplus myopathies. Interestingly, heterozygous variants in the Parkin gene were found in 2 of 9 investigated patients. We conclude that CC and HD in PD are predominantly myopathic. Aberrant protein aggregation may link PD and CC.

Mood and behavioural effects of subthalamic stimulation in Parkinson's disease

“…68,70,71 Paraspinal muscle biopsies showed unspecific myopathic changes with type 1 fiber hypertrophy, type 2 fiber loss, loss of oxidative enzyme activity, and myofibrillar disorganization. 68 Similar myopathic changes have been found in patients with tenotomy, suggesting that they could be secondary to altered proprioception in PD and result from, rather than induce, chronic postural deviations.…”

Camptocormia in Parkinson’s Disease: A Review of the Literature

“…The amorphous masses and myofibrillary disarrays stained positive for desmin and dystrophin, as with findings described in desmin-related myopathy or myofibrillar myopathy. Furthermore, they found unspecific myopathic changes in muscle biopsies including internalized nuclei, alterations in fiber size, and augmentation of connective tissue [24] . These findings are in general accordance with those of the above-named study [22] .…”

“…Spuler et al [24] examined 17 patients, 13 of them with a myopathic pattern in electromyographic recordings. The authors found 'apparently folded proteins' in muscle biopsies suggesting the possibility of a myopathy induced by an accumulation of aggregated proteins.…”

Presentation, Etiology, Diagnosis, and Management of Camptocormia

“…Only in single cases camptocormia may be the initial manifestation of Parkinson’s disease [30]. Camptocormia in Parkinson’s disease starts to develop between the age of 60 and 70 years [3] and the latency with which camptocormia occurs after onset of Parkinson’s disease is 5–10 years [1,31]. Camptocormia is most frequently found in patients with more severe Parkinson’s disease.…”

“…necrotizing myopathy, inflammatory myopathy, or mitochondrial myopathy [70]. Myopathic changes in patients with Parkinson’s disease include abnormal fiber size variation, increase of internal nuclei, increase of connective tissue, or myofiber disarray, or fatty degeneration [1,31]. In patients with advanced Parkinson’s disease and camptocormia muscle biopsy may show end-stage myopathy with autophagic vacuoles, chronic inflammatory myopathy, non-specific myopathic changes, or mitochondrial myopathy [33].…”