title: Physiological changes as a result of hip arthroscopy performed with traction.
abstract: OBJECTIVE
  To evaluate the physiological effects of hip arthroscopy using traction on venous blood flow, nerve conduction, soft-tissue injury, fibrinolysis, and patient pain.
  
  
  METHODS
  Thirty subjects were prospectively analyzed in an institutional review board-approved study. The visual analog scale pain score, creatine phosphokinase (CPK)-MM level, and D-dimer test were obtained preoperatively, postoperatively, and 5 days postoperatively. Doppler ultrasound (group A) (n = 15) of femoral and popliteal venous blood flow and somatosensory evoked potentials (SSEPs) (group B) (n = 15) of the posterior tibial nerve and superficial peroneal nerve were monitored intraoperatively.
  
  
  RESULTS
  Mean operation and traction times were 131.7 and 27.3 minutes, respectively. During traction (mean, 57.7 lb), decreased blood flow was determined at the popliteal vein (15 of 15 subjects) and femoral vein (4 of 15 subjects). Blood flow returned to baseline after traction in all subjects. Mean CPK-MM levels were 86.0 ± 29.6 mU/mL preoperatively, 232.1 ± 224.6 mU/mL postoperatively, and 138.1 ± 109.3 mU/mL at 5 days postoperatively. The number of subjects positive for D-dimer was 7 preoperatively, 12 postoperatively, and 21 at 5 days postoperatively. SSEPs showed a greater than 50% decrease in amplitude on the operative (8 of 15) and nonoperative (9 of 15) limbs. No significant correlations were determined between visual analog scale pain score, body mass index, CPK-MM level, traction time, or operating room time.
  
  
  CONCLUSIONS
  Doppler ultrasound showed decreased blood flow of the popliteal vein with traction, which returned to normal after traction. SSEPs showed changes with and without traction on operative and nonoperative legs. Consideration should be given for knee flexion of the contralateral leg after traction to protect nerve function. Hip arthroscopy resulted in an increase in a positive D-dimer test from immediately postoperatively to postoperative day 5. There is variability in the soft-tissue damage with hip arthroscopy, which is independent of time (<2 hours), body mass index, or pain. Traction affects the vascular and neurologic structures of the operative and nonoperative extremity independent of time.
  
  
  METHODS
  Level IV, therapeutic case series.
authors.affiliation: Oklahoma Sports Science & Orthopaedics, Oklahoma City, Oklahoma 73118, USA. haldavidmartin@yahoo.com
authors.forename: Hal D
authors.initials: HD
authors.lastname: Martin
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Palmer
authors.forename: Keith
authors.initials: K
authors.lastname: Champlin
authors.forename: Bill
authors.initials: B
authors.lastname: Kaiser
authors.forename: Bryan
authors.initials: B
authors.lastname: Kelly
authors.forename: Michael
authors.initials: M
authors.lastname: Leunig
mesh_terms: D001182:Arthroscopy / Q000379:methods*; D005260:Female; D006621:Hip Joint / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D014143:Traction