Friday, August 8, 2008

Good PFSS (patellofemoral stress syndrome) study

Pretty interesting article from the Aug 08 issue of JOSPT- "Proximal and Distal influences on Hip and Knee Kinematics in Runners With Patellofemoral Pain During a Prolonged Run". Goes something like this:

Recreational runners with & without patellofemoral stress sydrome were evaluated isometrically for hip abductor and external rotator strength. Next arch height was measured, and anatomical markers were placed on the hips and legs for 3D motion analysis. They then ran on a treadmill until they reached 85% max heart rate. Hip abductor/external rotation was re-tested.

The findings?

1. The PFSS group had weaker abdcutors, before & after the run.

2. External rotation strength was the similar in both groups, before & after.

3. PFSS group exhibited greater hip adduction at stance phase.

4. Arch height was similar in both groups.

5. In 80% of the males, 27% of the females, the hip remained in an abducted position for the 1st half of the stance phase. The researchers reported this was created by leaning the trunk towards the affected side.

A few questions:

1. The findings of similar ER strength between groups is inconsistant with previous PFSS studies. Why do you think?

2. Why didn't greater hip adduction in the PFSS group have any effect on arch height?

3. Why the gender difference in the compensation pattern for the increased hip adduction?

4. Only 2 muscle groups were tested, in one plane each. What other muscles may have turned up weak had they been tested?

I have my own ideas, but I do not want to pollute the waters with my bias- yet.

1 comment:

JH said...

Which came first the weak abductors or the pain? Withouit knowing how long they've been dealing with PFSS the weak abductors could be a result of miles of compensation due to pain.