Less Invasive Hip Surgeries Make Inroads

Hip replacement is one of the most successful operations in all of medicine, which prompts many orthopedic surgeons to think, as one leader in the field put it, “Why change something that doesn’t need fixing?”

But there are new techniques where improvements have been made, especially with regard to reducing complications and speeding recovery.

The technique some surgeons use is called anterior hip replacement, one of several minimally invasive operations that are associated with a shorter hospital stay, smaller incision, less trauma to muscles, less pain and blood loss, reduced risk of dislocation after surgery, faster healing and a quicker return to normal activities. The operation was introduced in the United States more than two decades ago by Dr. Joel M. Matta of the St. John’s Health Center in Santa Monica, Calif., who also helped design a special operating table to simplify the procedure.
Another minimally invasive form of hip replacement, the PATH technique, was developed by a Los Angeles orthopedist, Dr. Brad L. Penenberg
The usual reasons for hip replacement are osteoarthritis, rheumatoid arthritis and traumatic arthritis, all of which can cause pain and stiffness that limit mobility and the ability to perform activities of daily living. Most patients try less drastic measures — manual therapy, medications (pain relievers, anti-inflammatory drugs and glucosamine supplements), injections of hyaluronic acid and walking aids — before deciding that surgery is their best hope for escaping chronic pain and disability.

To appreciate the potential benefits of minimally invasive methods, it helps to know how hip replacements are usually done.
General or spinal anesthesia is used for the operation, which typically takes one to two hours. An incision 25 to 30 centimetres long is made through the muscles on the side of the hip to expose the hip joint, and the diseased bone tissue and cartilage are removed. An artificial socket is then implanted into the pelvic bone and a metal stem is inserted into the thigh bone, the top of which is replaced by a metallic ball to create a ball-and-socket joint that mimics the function of a natural hip joint.

The average hospital stay is four or five days, followed in most cases by extensive rehabilitation. Patients are told not to cross their legs or bend at the hip more than 90 degrees after surgery — in some cases indefinitely, because these motions can cause dislocation of the replaced joint that requires a repeat operation.
Possible complications of the surgery include blood clots, infection, fracture and a change in leg length. Possible delayed complications include dislocation of the new joint, breaking or loosening of the prosthesis and stiffening of the tissues around the joint. Although modern materials have extended the life of implants to 20 years or so, they can eventually wear out and require replacement.

Studies comparing long-term results of minimally invasive hip replacement with more traditional surgery have had mixed results, and all forms of hip replacement have benefited from improved anesthetic and pain management techniques. Surgeons who routinely use less invasive methods maintain that there are decided advantages for most patients, even though the operation itself can take somewhat longer.
Perhaps most important is that major muscles in the buttocks and thigh that help to stabilize the hip joint are not cut, reducing the risk of dislocation and speeding recovery. Patients spend less time in the hospital and return to normal life more quickly.
It takes time to become adept at the procedure, as with any complex surgery. In choosing a surgeon, ask how many of the operations the surgeon has done using the proposed technique and with what results.
Regardless of the type of operation it helps to have supporting muscles as strong as possible before surgery, perhaps through several sessions with a physical therapist if the patient’s condition allows it.