Abstract
Background
Venous thromboembolisms are serious complications of arthroplasty of the lower extremities. Although early ambulation and active leg exercise is recommended, postoperative patients with surgical pain have difficulty in moving their legs. Therefore, we developed a novel leg exercise apparatus (LEX) to facilitate active leg movement even during the early postoperative period (Fig 1). LEX is a portable apparatus that allows patients to actively move their legs while in the supine position. LEX enables dorsiflexion, plantar flexion, combined eversion and inversion of the ankle, and multi-joint movement of the leg.
Objectives
To describe how LEX facilitates active movement of the leg and thereby increases venous flow in the lower extremities.
Participants and Methods
-
The venous flow volume of the femoral vein of 8 healthy volunteers; 5 men and 3 women, with a mean age of 22.4 (range, 22–26) years, were measured by duplex ultrasonography. The measurements were repeated at 1, 3, 5, and 10 minutes after the completion of one-minute active ankle exercise with LEX, and during the 10-minute use of an intermittent pneumatic compression (IPC) device.
-
The same measurements were taken from 8 healthy volunteers; 5 men and 3 women, with a mean age of 21.6 (19–26) years, after three types of 1 minute LEX exercise: rapid dorsiflexion-plantar flexion (60 reps/min), slow dorsiflexion-plantar flexion (30 reps/min) and combined motion of the leg (30 reps/min). These measurements were repeated at 1, 10, 20, and 30 minutes after the 1 min-LEX exercise.
Statistical methods
All data were analyzed in a two-way repeated measures analysis of variance. Post-hoc analyses were performed using the Bonferroni comparisons test. The probability level accepted for statistical significance was p < 0.05 (SPSS Statistics Version 21).
Results
-
Whereas the flow volume of the femoral vein after the 1 min-LEX exercise increased 2.00-fold over the baseline level, the value at 1 minute after the start of IPC did 1.18-fold (p = 0.033). The flow volume at 10 minutes had increased 1.50-fold; the corresponding values during IPC use were the same as those during rest (Fig 2).
-
The flow volume after the 1 min-LEX exercise had increased for 30 minutes. After 30 minutes of rapid dorsiflexion-plantar flexion, it increased 1.63-fold over the baseline level. While 1 minute after slow flexion, the flow volume increased 1.38-fold and remained on the same level, this value was 1.53-fold at 30 minutes after combined leg motion. The combined leg exercise made the flow volume higher than dorsiflexion-plantar flexion at equal speed (Fig 3).
Discussion
Short periods of LEX use improved the venous flow volume of the femoral vein more than continuous use of IPC. The 1-min LEX exercise had improved the femoral venous flow volume for 30 minutes, and combined leg exercise was more effective than a single ankle exercise. These results suggest that LEX exercise can induce the lower-extremity venous flow greater than that achieved using IPC.
Clinical Relevance: LEX might be effective for enabling postoperative patients to move their legs and to improve venous flow of the lower extremities.
