Unfortunately, every now and then the pain returns. It comes from my sacroiliac joints (SIJ). These are the relatively immobile joints towards the back of your pelvis.
A variety of causes can trigger inflammation of the joint which results in pain (sometimes severe), slightly laterally in your lower back. The pain may radiate down into your buttock and thigh but never below the knee. Sitting forward or lying on the affected side sometimes worsen the pain. It is not clear what predisposes to this - laxity of the ligaments may be important. Certainly this is a common problem in pregnancy when hormones ensure greater joint mobility to allow birth. Some believe it is reduced movement, lack of muscular support or wear on the articular surface. However it remains a clinical diagnosis - no X-ray, blood test or even MRI will detect a change (however much pain you're in). By and large, apart from the pain, its harmless.
Superficial stimulation, be it massage, acupuncture, heat etc. will all help to disrupt the pain pathway and relieve pain. Rest and anti-inflammatories will reduce the inflammation and then it's back to building up your back muscles again.
Developing good protective back muscles requires the extensor muscles to be activated and this is something we don't often do in sport as much as we should. I suspect my latest bout was brought on by neglecting these exercises, so I'm back to doing Yoga before bed and paying careful attention to my karate stances!
