Harris-Hayes M, Steger-May K, Van Dillen L, Schootman M, Salsich G, Czuppon S et al. Reduced hip adduction is associated with improved function after movement-pattern training in young people with chronic hip joint pain. J Orthop Sports Phys Ther. 2018;48(4). 316-324.
The topics of hip impingement and hip pain are near and dear to our hearts here at GoFit and a clinical interest of ours. The article reviewed here uses the term hip joint pain to encompass a number of potential and often related diagnosis (femoracetabular impingment, developmental dysplasia, labral tears, and chondral lesions).
Hip joint pain is a big problem. Especially for young, athletic women. Unfortunately, there isn't a great amount of high-quality research to suggest the best method of treatment. Despite this there has been a huge growth in the amount of surgeries to treat these various conditions.
We talk a lot about manual therapy on the blog, likely because we are manual therapists and that is where our interests lie. But changing movement patterns is just as important in improving pain and function long term. This article is interesting because it looked at the effect movement retraining would have on individuals with chronic hip joint pain.
The patients who participated in this study were between the ages of 18-40 years old, mostly women, who had deep hip pain or groin pain that had been present for at least 3 months. The pain had to be reproduced with a classic impingement test that brought the hip into flexion, adduction, and internal rotation. The authors used some pretty cool 3D kinematic technology to see how the effects of specific movement retraining would have on the person’s ability to correctly perform a single leg squat. They also looked at hip abductor strength and even looked to see if there were structural changes to the head of the femur w/ MRI imaging.
Participants in the study had 6 one-hour sessions over a 6-week period. During these sessions a physical therapist provided instruction in movement of daily functional tasks and patient specific tasks with practice throughout. The patient was asked to perform the specific movements that they were deemed independent with as their home exercise program.
The authors hypothesized that this specific movement retraining would reduce the amount of relative hip adduction the patient had during a single leg squat. This is important because increased hip adduction has been associated with "impingement'' type pain. They also believed that hip abductor strength would increase over the course of treatment.
This was a relatively complex study in the sense that there were a lot of moving parts. With this study, as with most studies, making generalizations can be difficult and results should be taken cautiously. With that being said, there appears to be a couple of take home messages here. The first is that retraining movement during patient specific and functional tasks did work to reduce patient's hip adduction during specific movements. Those who had a greater reduction in hip adduction also had a greater improvement in pain and function assessed through patient specific scales. Interestingly there was no change in hip abductor strength. This suggests that motor control and the timing of muscle activation may play a more important role in stabilizing the hip than pure strength. Also, of note the patients that reported a greater compliance to their home exercise program showed a greater reduction in hip adduction.