Painful abdominal contractions in patients with Parkinson disease.

We hypothesized that the unusual and painful abdominal contractions in two of our patients with Parkinson disease (PD) were linked to abdominal muscle hypertrophy. The abdominal pain was aggravated by sitting, standing, or walking, and was characterized by a powerful pulling sensation associated with palpable contractions of the rectus abdominis. When the pain decreased, the camptocormia abated. The thickness of the rectus abdominis and the relative muscle thickness ratio were greater in the two patients with abdominal contractions than in the control patients with PD without abdominal contractions. Palpable painful abdominal contractions could be associated with the presence of hypertrophy of the rectus abdominis visible on CT scan. The abdominal muscle contractions probably contribute to the development a stooped posture.