title: A novel apparatus for active leg exercise improves venous flow in the lower extremity.
abstract: BACKGROUND
  Venous thromboembolism is a serious complication associated with major orthopedic surgery to the lower extremities. Although active ankle exercise is recommended, patients with postoperative pain may have difficulty moving their ankles. Therefore, we developed a novel leg exercise apparatus (LEX) to facilitate active ankle movement during the early postoperative period. We describe how LEX facilitates active movement of the leg, and thereby increases venous flow in the lower extremities.
  
  
  METHODS
  The femoral venous flow volume and velocity in 8 healthy volunteers (5 men, 3 women; mean age 22.4 years; age range 22-26 years), were measured using duplex ultrasonography. Measurements were repeated 1, 3, 5, and 10 minutes after the completion of 1 minute of active ankle exercise using LEX, and during a 10-minute period of intermittent pneumatic compression (IPC) device use.
  
  
  RESULTS
  The flow volume after 1 minute of LEX exercise increased 2.63-fold from baseline; elevated values persisted for 10 minutes. Flow volume at 10 minutes was increased 1.71-fold from baseline. The corresponding values during IPC did not differ from resting values. The mean velocity 1 minute after LEX exercise increased 2.34-fold from baseline; in contrast, mean velocity 1 minute after the start of IPC had decreased 0.90-fold (P=0.009).
  
  
  CONCLUSIONS
  A 1-minute period of LEX exercise improved venous flow in the lower extremities, compared with continuous use of IPC. Use of LEX might facilitate improved ankle mobility, and therefore reduced risk of thromboembolism, in postoperative patients.
authors.affiliation: Department of Rehabilitation Medicine, University of Tsukuba Hospital, Tsukuba, Japan.|Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.|Department of Orthopedic Surgery, Ibaraki Prefectural University of Health Sciences Hospital, Ami, Japan.
authors.forename: Yukiyo
authors.initials: Y
authors.lastname: Shimizu
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan - hkamada@md.tsukuba.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kamada
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Sakane
authors.affiliation: Department of Cardiovascular Surgery, University of Tsukuba Hospital, Tsukuba, Japan.
authors.forename: Shizu
authors.initials: S
authors.lastname: Aikawa
authors.affiliation: Department of Orthopedic Surgery, Ibaraki Prefectural University of Health Sciences Hospital, Ami, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Mutsuzaki
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Mishima
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.|Department of Orthopedic Surgery, Kikkoman General Hospital, Noda, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Ochiai
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Yamazaki
mesh_terms: D000328:Adult; D000842:Ankle / Q000098:blood supply / Q000502:physiology; D001783:Blood Flow Velocity; D015444:Exercise / Q000502:physiology; D005081:Exercise Therapy / Q000295:instrumentation*; D005260:Female; D005268:Femoral Vein; D064368:Healthy Volunteers; D006801:Humans; D007564:Japan; D007866:Leg / Q000098:blood supply* / Q000502:physiology*; D008297:Male; D009985:Orthopedics; D011182:Postoperative Care / Q000379:methods; D011183:Postoperative Complications / Q000517:prevention & control; D020246:Venous Thrombosis / Q000517:prevention & control*; D055815:Young Adult