The hip is a ball and socket joint where the leg bone joins with the pelvis. The femur, or thigh bone, is ball-like at the end, and this ball fits into the pelvic bone, which is the socket. Inside of this joint, between the femur and the pelvis, is a smooth layer of cartilage called the hip labrum. The hip labrum is the lining on the socket that creates suction and stability inside the hip joint, allowing smooth movement for activities such as walking or running — any movement requiring hip rotation.
The hip labrum is very important for proper hip function. As the leg moves, it must rotate within the pelvic joint, and the femur bone must be able to glide past the pelvic bone. If the labrum is injured, the hip can not move smoothly, and this often produces an instability, with pain and a clicking or locking sensation. The clicking and locking occur when the labrum, which is normally a very smooth surface, is worn down from repeated use or torn from a sudden motion. Athletes such as runners, tennis players, and soccer players, who often use repeated motion during exercise, are a higher risk for overuse or sudden injuries to the labrum.
A tear of the hip labrum is usually diagnosed by an orthopedist. The doctor can test the movement of a patient's hip to check for irregularities. If a labral tear is suspected, it is likely the doctor will request magnetic resonance imaging (MRI) scans to get clear images and information about the location and size of the tear.
Treatment for labral tears include rest from athletic activities, physical therapy to increase flexibility, and the use of anti-inflammatory medications to decrease inflammation around the hip labrum and the hip joint. Patients who continue to experience pain or decreased range of motion in the hip may be referred for arthroscopic surgery of the hip. This surgery is typically performed through two small incisions on the outside of the hip. A orthopedic surgeon uses special instruments to clean and repair the injured area of the hip labrum.
Recovery from arthroscopic hip surgery can take up to six weeks, and often includes physical therapy. A successful surgery can repair tears or worn areas on the labrum, leaving the surface smooth. Upon recovery, a patient usually regains full range of motion in the hip, and the hip labrum normally remains intact. Although there are some indications that labral tears may later lead to arthritis of the hip, there is no definite evidence, and experts agree further research about the long-term effects of labral tears is warranted.