The gluteus medius is a muscle that sits on the outside of the hip area. This muscle is used for standing upright and walking. When injured, these muscles will cause a limp. If these muscles are torn, it can cause severe pain when walking, sitting, or sleeping. Treatment usually involves rest, physical therapy, and sometimes surgery to repair the torn muscle, if no other treatments bring relief from pain.
Piriformis syndrome is a type of neurological injury that is caused by compression of the sciatic nerve. The piriformis muscle sits deep within the buttock, behind the gluteus maximus. It starts at the lower spine and connects to the femur muscle. This nerve can become compressed from swelling of the piriformis muscle due to injury or muscle spasms or inflammation. Piriformis syndrome causes symptoms including pain in the back of the thigh, pain in the back of knee, buttock pain, pain in the calf, pain in sciatic nerve branches (pain in the nerves of leg and the buttocks, then), shooting pain in the legs, and hip pain after sitting.
The sacroiliac joint connects the lower spine to the pelvis and any injury or strain to this area can cause a lot of back, hip, groin, and sciatic pain. Sacroiliac joint dysfunction (SJD) can cause not only radiating lower back pain but can also severe pain in the hip area including hip pain at night when sleeping and hip pain when sitting. Often the pain resembles that of a hip injury it is so severe. SJD can also cause severe pain in the groin area. Women may also notice pain running along the distribution of the sciatic nerve. Treatment for sacroiliac joint dysfunction includes rest, anti-inflammatory drugs, and sciatic nerve massage.
Grade III (severe): A complete tear in your muscle that causes severe pain and swelling and you can't bear weight on that leg, making it difficult to walk. You've also lost more than 50 percent of your muscle function. These injuries are less common and may need surgery to repair the torn muscle. They can take several months or more to completely heal.