Aug 2015 22

The piriformis muscle

By: Dave Wheeler

Ever wondered why your hips ache after driving a long way, cycling for some time, running or  walking a reasonable distance?

It may well be that the piriformis muscle is the villain.

The piriformis is one of a group of 6 outward rotators of the hip - think of the footballer warming up for the match who does the "open gate" movement with his leg bent held out in front of him, then rotating outwards. Or the dancer doing a turn-out.

Whilst there are 5 other muscles in this group, because of the way that the piriformis sits within the body, it tends to be the culprit if things get over worked.


The function of the piriformis



The diagram shows the pelvis as seen from the rear. The piriformis in red sits underneath the glutes (the muscles of the buttocks) - if you imagine it contracting then it will pull the top of the leg back round the body, a movement called lateral hip rotation.

If you cross your legs the "bloke's way"  by crossing your ankle over the other knee, then your hip has rotated outwards.


When the piriformis causes problems

You can see why dancers who do lots of outward rotation of the upper leg might end up with a really well defined piriformis. But there are other causes of the piriformis becoming overly tight (or  hypertonic) might be:


  • Cycling. Unless your pedals & cleats are absolutely perfectly fitted and aligned for your body & leg length, then you may well find that your knee goes very slightly out on your up and down stroke. This will cause a very tiny outward rotation of the hip - the thing is, tho' it's a small movement, you do it thousands upon thousands of time with every ride, so the piriformis can quickly become really tight.
  • Running & walking. If you walk and run in a perfectly straight line like a model on the catwalk all the time, then you're unlikely to get an overused piriformis. For the rest of us, though, the chances are that on one or both sides our leg will move very slightly outwards with each stride. This is a tiny outwards rotation of the hip, which again will quickly accumulate into an overuse problem with the piriformis.
  • Driving. Next time you get in your car, check whether your feet are in a perfectly straight line with an imaginary line coming from your hips. There are a few models of car (some of which are really popular with business-people who do a lot of miles) where the pedals are offset. These offset pedals mean that one of your hips is going to be kept in an outwardly rotated position for the duration of every trip. Even if you're lucky enough to have well-aligned pedals, if you swivel your right foot on your heel between accelerator and brake rather than lift it off each time, you're still over-using your piriformis.

So what?

An hypertonic piriformis can cause an ache in the hip, but for most people, it's just one of those things. The problem with allowing the muscle to become too "toned" (that is, overusing it too much) is that it lies close to the sciatic nerve, and if piriformis gets too big, it can compress the nerve, causing symptoms akin to sciatica:

  • lower back pain
  • shooting pain down the leg


Treating the piriformis

Piriformis is buried underneath the glutes, and is really only accessible when your leg is at 90 degrees. I use a combination of remedial massage techniques including deep tissue massage and soft tissue release, with the client lying on their side,  leg bent at 90 degrees.

Partly because it's so easy to over-use and become really tight, and partly because it's so hard to stretch, having treatment on your piriformis isn't exactly comfortable.

Oh, ok, it's painful.

As ever, if you think I can help, give me a call.