title: Diagnostic biopsy of the pronator teres and a motor branch of the median nerve: indications and technique.
abstract: OBJECTIVE
  Biopsy of muscle tissue and motor nerve is helpful in the neurological evaluation of patients who present with upper limb and/or diffuse motor weakness. The procedure is indicated to supplement clinical, serological, and imaging diagnostic work-up of myopathic and neuropathic disorders. We describe a surgical technique and clinical series of biopsy of the pronator teres muscle and a motor branch of the median nerve.
  
  
  METHODS
  We performed a retrospective review of 20 patients who underwent biopsy of the pronator teres and a motor branch of the median nerve as part of a clinical, serological, and radiographic evaluation for weakness of the upper extremity. All of the biopsies were performed by a single surgeon. The surgical technique is described. Follow-up visits with both the surgeon and the neurologist were reviewed to evaluate preoperative and postoperative neurological function to identify any changes in nerve or muscle function and any postoperative complications.
  
  
  RESULTS
  Biopsied tissue was sufficient for pathological diagnosis in all 20 patients. Diagnoses included multifocal motor neuropathy in 14 patients, amyotrophic lateral sclerosis in 3 patients (2 sporadic; 1 familial), inclusion body myositis (1 patient), inflammatory myopathy (1 patient), and chronic inflammatory demyelinating polyneuropathy (1 patient). At a mean follow-up of 11 weeks (range, 5-31 wk), there were 6 minor surgical complications, all of which were superficial hematomas that resolved with use of a compressive wrap.
  
  
  CONCLUSIONS
  Biopsy of the pronator teres and a motor branch of the median nerve was safe and effective. The technique is particularly useful when considering the diagnosis of multifocal motor neuropathy affecting the upper extremity.
authors.affiliation: Division of Hand and Upper Extremity Surgery, Department of Neurology, Hospital for Special Surgery, New York, NY, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Dy
authors.forename: Dale J
authors.initials: DJ
authors.lastname: Lange
authors.forename: Kristofer J
authors.initials: KJ
authors.lastname: Jones
authors.forename: Rohit
authors.initials: R
authors.lastname: Garg
authors.forename: Edward F
authors.initials: EF
authors.lastname: DiCarlo
authors.forename: Scott W
authors.initials: SW
authors.lastname: Wolfe
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis; D001706:Biopsy; D005260:Female; D005542:Forearm / Q000294:innervation; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000473:pathology*; D020423:Median Neuropathy / Q000473:pathology*; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000175:diagnosis; D018908:Muscle Weakness / Q000473:pathology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000473:pathology*