In the event of failure of conservative treatments, Total Hip Arthroplasty (THA) is a safe and viable intervention. This procedure has the benefits of decreasing pain and improving functioning in a person. Even so, the patient suffers from weakness of the hip abductors following THA surgery. This may cause pain or limited functionality for the patient. Exercise regimes have been suggested to help alleviate these problems by increasing muscle strength. This paper will review the article by Jacob Cales, et al., “Electromyographic Analysis of Hip Abductor Exercises Performed by a Sample of Total Hip Arthroplasty Patients evaluates the effectiveness of hip abductor strengthening exercises”. The review shall analyze the use of abduction exercises which are some of the most common hip exercises following surgery.
Abduction exercises are categorized as Weight Bearing (WB) and Non-Weight Bearing (NWB) exercises. In non-weight bearing standing abduction, the patient has a cuff weight which is equivalent to 1% of their body weight attached to the ankle of the involved leg. The exercise begins with the patient having their legs together while hands rest on a scale that is placed on a table. The patient should ideally place the minimum amount of pressure on the scale so as to limit the use of the upper extremity in the exercise. In carrying out the exercise, the patient abducts their leg until the foot involved reaches the desired height. The foot is returned to the start position and the procedure is repeated.
In Weight-Bearing Standing abduction, the exercise is performed in the same manner as with the NWB but with the cuff weight now attached to the ankle of the moving leg. The leg with the weight is then moved through a 30° arc and back to the starting position. This exercise helps to alleviate stress to the extremities as well as strengthen the abductor’s muscles.
For patients who have trouble standing, Side-Lying abduction is applicable. In this exercise, a cuff mass that weights 0.5% of the patient’s total weight is placed on the ankle of the stationary limb. Pillows are positioned between the knees of the patient to ensure that the leg rests at 0° of hip abduction during the exercise. The patient then moves the leg to create a 30° hip abduction and back to the original position.
The other abduction exercise is Resisted Side-Stepping Exercise. In this exercise, an elastic resistance band is applied to the patient’s ankles. The resistance level of this band should be equivalent to a peak external torque of 1% of the patient’s body weight. The patient begins the exercise in a standing position with feet approximately 30cm apart. In this position, the resistive band is taut but does not have any tension. The patient then side steps to the involved side by a distance that is equal to half of their leg length. The patient then moves their uninvolved leg towards the involved leg so as to return the length to its start position.
The exercises highlighted herein result in the strengthening of hip abductor muscles. This is very significant since the weakness of this muscle group may be apparent even 2 years after THA. According to Jacobs, et al., both Weight Bearing and Non-Weight bearing abduction exercises are effective and can be used interchangeably. The exercise protocol if followed strictly results in improved lower extremity strength for the patient. As such, these exercises assist patients to return to function quickly following their surgery.
References
Jacobs, A. et al. (2008). “Electromyographic Analysis of Hip Abductor Exercises Performed by a Sample of Total Hip Arthroplasty Patients”. The Journal of Arthroplasty 24(7):1130-6.