Camptocormia as a presentation of generalized inflammatory myopathy

Abstract

Camptocormia is an abnormal truncal flexion posture that occurs while walking or standing. It is usually caused by various hypokinetic movement disorders such as Parkinson disease and multiple system atrophy. Myopathy or motor neuron disease can also be infrequent causes of camptocormia. Paraspinous muscle biopsy usually reveals focal myositis, regardless of the etiology of camptocormia. We describe the first case of generalized inflammatory myopathy with prominent camptocormia and proximal muscle weakness. Muscle biopsy of the quadriceps confirmed the diagnosis of polymyositis, and the posture showed modest improvement in response to steroid treatment.

FIGURE 1.

MRC rating scale prior to steroid treatment (A) and approximately 4 months after IVMP initiation (B). WF, wrist flexors; WE, wrist extensors; HF, hip flexors; HE, hip extensors; KF, knee flexors; KE, knee extensors; PF, plantar flexion; DF, dorsal flexion.

FIGURE 2.

The patient demonstrated flexed posture while standing (A) and was able to correct the posture with her hands “climbing up” the wall (B).

FIGURE 3.

Axial lumbar spine MRI showed T2 hyperintensity in bilateral paraspinous muscles consistent with near complete fatty replacement of the muscles (A). Axial MRI of thigh muscles revealed T2 hyperintensity of bilateral vastus lateralis and intermedius muscles (B), indicating a generalized myopathic process.

FIGURE 4.

Muscle biopsy of the rectus femoris muscle in hematoxylin and eosin stain showed endomysial infiltration of lymphocytes (A) with increased MHC I expression on the muscle membrane (B). CD8-positive cells (C) were more prominent than CD4-positive cells (D), and the pathological findings are consistent with polymyositis.