Piriformis syndrome is a condition in which the piriformis muscle, located in the buttock region, spasms and causes buttock pain. The piriformis muscle can also irritate the nearby sciatic nerve and cause pain, numbness and tingling along the back of the leg and into the foot (similar to sciatic pain).
A common cause of sacral and lower back pain is trigger points in the gluteus medius muscle. This muscle is located in the hip and is responsible for abduction and stabilization of the hip and pelvis. This muscle often harbors trigger points. These knots will often refer pain into the sacrum and lower back area
Low back pain can be a complicated condition. Quite often in my practice I will see multiple muscles involved in causing lower back pain in my clients. For example trigger points in the hip flexors like the psoas muscle, along with trigger points in the back muscles themselves, such as the quadratus lumborum or the multifidus, can all be active and refer pain into the low back. When trigger points are active in multiple muscles at once this is called a chronic myofascial pain syndrome.
The quadratus lumborum muscle or QL. Is a muscle in the lower back. It helps to flex the spine to the side and stabilize the lowback and hip. Trigger points in this muscle are one of the most common causes of low back pain and stiffness. This is probably the most frequent muscle I work on in my practice when treating clients with low back and hip pain.