It sounds like you might have a condition called femoroacetabular impingement (FAI). With FAI, the top of the femur (thigh bone) pinches the rim of the hip socket. The area that gets compressed is referred to as the acetabular rim. This type of impingement occurs most often when the hip is flexed and internally rotated.
Surgery is often recommended as the most successful treatment for this problem. There are three surgical choices: 1) surgical hip dislocation, 2) periacetabular osteotomy, and 3) hip arthroscopy. Surgical hip dislocation is considered the current gold standard, though some experts expect improved arthroscopic techniques will change that in the future.
Surgical dislocation refers to taking the femoral head out of the socket and making adjustments and
repairs as necessary, and then putting the head back in place. The operation can be done without cutting through the muscles and with the least amount of trauma possible. Any damage to the labrum (rim of cartilage around the hip socket) can be repaired. Any problems with mismatch of the femoral head and neck with the acetabulum (hip socket) can be taken care of. This type of surgery allows for preservation of the joint, which is important in young, active adults.
Periacetabular osteotomy corrects the retroversion (tipped or tilted position of the acetabulum). The capsule surrounding the hip joint is cut open. The femoral head and neck are reshaped by shaving or cutting off portions of the bone. The goal is to correct the placement of the femoral head in the hip socket.
The third surgical option (hip arthroscopy) to treat FAI allows the surgeon to gain access to the inside of the joint without cutting it open. This avoids pulling the femoral head away from the socket. Arthroscopic surgery also makes it possible to reattach (rather than remove) a torn labrum.
Studies show that the best way to approach this problem is by restoring as normal hip anatomy as possible. Surgical hip dislocation is used with good success for patients with mild to moderate (but not severe) degeneration of the joint cartilage, surface, and surrounding capsule.
It sounds like your surgeon is right on track with current evidence for best practice. You can always seek a second opinion to help you understand your condition and the various treatment options available.