title: Ultrasound appearance of forearm muscles in 18 patients with complex regional pain syndrome 1 of the upper extremity.
abstract: OBJECTIVE
  To explore the potential diagnostic utility of musculoskeletal ultrasonography (USG) changes in complex regional pain syndrome type 1 (CRPS-1) of the upper extremity.
  
  
  METHODS
  With informed consent, 18 consecutive patients referred to our institution with CRPS-1 of the upper limb were examined with ultrasound scanning of both upper limbs. Qualitative comparison of the scan of the forearm muscles of the affected side with the unaffected side was made.
  
  
  RESULTS
  The muscles affected by CRPS-1 demonstrated increased echogenecity. The outlines of the muscles were either indistinct or completely obliterated. A group of several muscles appeared like one homogenous, hyperechoic mass, with loss of normal architecture. Compared with the unaffected side, the muscle thickness on the CRPS-1 side measured by calipers on ultrasound was reduced irrespective of the duration of disability or disuse of the hand. The flexors and extensor muscles of the forearm were maximally affected.
  
  
  CONCLUSIONS
  Ultrasonography provides useful anatomical information, regarding structure, kinesiology, and gross pathological changes of muscle, that may prove useful in understanding the motor impairment associated with CRPS-1. USG shows promise as a cost-effective bedside tool for the diagnosis of CRPS-1 and in guiding physical therapy.
authors.affiliation: Ashirvad Pain Relief Clinic, Plot. No. 117, Shubh Ashirvad, Road No. 5 Hindu Colony, Dadar East, Mumbai 400014, Maharashtra, India. lakshmi@paincareindia.com
authors.forename: Lakshmi Champak
authors.initials: LC
authors.lastname: Vas
authors.forename: Renuka
authors.initials: R
authors.lastname: Pai
authors.forename: Mahesh
authors.initials: M
authors.lastname: Radhakrishnan
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005542:Forearm / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging*; D010147:Pain Measurement; D012019:Reflex Sympathetic Dystrophy; D018608:Ultrasonography, Doppler; D034941:Upper Extremity / Q000473:pathology*