Pain from the hip joint may be felt anteriorly (in front of the hip) as groin pain, laterally over the greater trochanter, or posteriorly in the buttock. Sometimes the patient may complain of knee pain which has been referred from the hip.
- Trauma to the hip: With a fall, direct blow, twist, or stretch, the pain is felt almost immediately.
- Overuse injury: The onset of pain may be delayed by minutes or hours as inflamed muscles surrounding the hip joint go into spasm or joint surfaces inflame, causing fluid accumulation.
- Pain: Most often pain is felt in the front of the hip, but the joint is three-dimensional. Pain may be also felt along the outside part of the hip or even in the buttock area.
- Limp: Limping is the body's way of compensating for pain by trying to minimize the amount of weight the hip has to support while walking. Limping is never normal. Limping produces abnormal stresses on other joints, including the back, knees, and ankles and if the limp persists, these areas may also become inflamed and cause further symptoms.
- Fracture: With a hip fracture, there is an acute onset of constant pain after the injury that usually is made worse with almost any movement. The muscles that attach to the hip cause the fracture to displace, or move, and the leg may appear shortened and rotated outward. If no displacement occurs, the leg may appear normal. Pelvic fractures may have pain similar to a hip fracture but the leg appears normal.
- Sciatica pain: Pain from sciatica tends to start in the back and radiate to the buttocks and to the front or side of the hip. It may be described in different ways because of nerve inflammation. Some typical descriptive terms used for the pain of sciatica include sharp, stabbing, or burning. The pain of sciatica may be made worse with straightening the knee, which stretches the sciatic nerve and may make it difficult to stand from a sitting position, or walk with a full stride. There may be associated numbness and tingling. Loss of bowel and bladder function associated with the pain may signal a neurosurgical emergency and the presence of cauda equina syndrome. If not recognized and treated with immediate surgery, there is risk for permanent damage to the spinal cord.
- Arthritis: If arthritis narrows the hip joint or impinges on the way the femoral head can glide in the acetabulum, or if there is a cartilage or labrum tear, the pain may be associated with a "catch," or a feeling like there is something impeding hip movement.
- Pain from arthritis tends to be worse after a period of inactivity and gets better as the joint "warms up" with use. But as activity increases, the pain will return.
When health-care practitioners talk about a hip fracture, they really mean a fracture of the proximal or upper part of the femur. The precise location of the fracture is important, because it guides the decision of the orthopedic surgeon as to which type of operation is needed to repair the injury.
Aside from a fall, any trauma can potentially cause a hip fracture. Depending upon the mechanism of injury, the femur may not break; rather, a portion of the pelvis (often the pubic ramus) may be fractured. The initial pain may be in the hip area, but examination and X-rays may reveal a different source of the injury. Trauma can also cause a hip dislocation in which the femoral head loses its relationship with the acetabulum. This is almost always associated with an acetabular (pelvic bone) fracture; however, in patients with hip replacements, the artificial hip may dislocate spontaneously
Other structures should be mentioned as a cause of hip pain because they become inflamed. The iliotibial band stretches from the crest of the pelvis down the outside part of the thigh to the knee. This band of tissue may become inflamed and cause hip pain, knee pain, or both. This is a type of overuse injury that has a gradual onset associated with tightness of the muscle groups that surround the knee and hip. Piriformis syndrome, in which the piriformis muscle irritates the sciatic nerve in the buttock, can also cause significant posterior hip pain.