Direct Anterior Hip Replacement
Total hip replacement (also known as total hip arthroplasty) is a surgical procedure that replaces a worn native hip joint with a metal implant with the aim to provide pain relief and restoration of function. To ensure successful surgery this procedure is best done by an orthopaedic hip surgeon.
The reasons for the hip joint to become degenerate are multiple. The most common cause is osteoarthritis. Other causes include childhood hip disorders, fractures around the hip, avascular necrosis (loss of blood supply), infection, increased stress (overuse, overweight), inflammation such as rheumatoid arthritis.
The reason to replace a worn joint is pain that is causing considerable disability to a patient. The level of disability is highly variable among patients. Some patients require hip replacement because they cannot work and some because they are unable to do their leisure activities such as playing golf. Others choose to wait until their pain and disability interfere with walking and the activities of daily living. The decision to proceed to hip replacement is subjective and very personal. I am a specialist orthopaedic hip surgeon and I will discuss with you the benefits of surgery but also the risks associated with a hip replacement. I always advise patients to take plenty of time to think it over. Talk to your family and your local doctor about it. Feel free to ask me any questions you can think of. The patients are the ones deciding when the right time to proceed with surgery is. A total hip replacement is a very successful procedure with satisfaction rates as high as 96% in multiple research studies.
Once a decision to proceed with surgery has been made I will discuss with you the surgical options that are likely to provide the best outcomes. A surgical plan needs to be formulated. This plan takes into consideration the patient’s hip joint deformity, surgical anatomy, previous surgical procedures, medical co-morbidities. Amongst other things, surgical options include surgical approach and hip implants.
I have been trained in performing Direct Anterior Hip Replacement and posterior hip replacement. After performing a large number of hip replacements using both approaches, my preferred surgical approach is the Direct Anterior Hip Replacement. This approach is a minimally invasive approach that maintains muscle integrity (avoids cutting any muscles) and allows a recovery and lifestyle free of any hip precautions. The approach is done in the plane between the tensor fascia lata muscle and the sartorius muscle with preservation of both muscles. Next an incision in made into the capsule of the hip joint and the hip is dislocated. The femoral head is then resected, the acetabulum is prepared and an acetabular implant is inserted. A press-fit implant with a biologically active surface is implanted in the majority of patients. This allows early bone-implant integration. The next step of the procedure involves the femoral exposure and femoral preparation for the implantation of the femoral component of the total hip replacement. In patients where the surgical anatomy allows, a femoral neck preserving implant (“mini hip”) is used to preserve as much of the native bone as possible. Otherwise a standard femoral component is used. Both these implants are coated with a biologically active surface for bone-implant integration and are press-fitted into the native bone. A ceramic on ceramic bearing surface is used and the hip joint is reduced. Prior to wound closure, an intraoperative X-ray is taken to ensure correct implant positioning with accurate reconstruction of the leg length and femoral offset (“width of the hip”).
In a small group of patients, due to abnormal surgical anatomy, requirement for custom, patient specific implants, posterior acetabular wall fracture, a posterior approach hip replacement may be required. This approach is done through the posterior aspect of hip joint and requires the short external rotator muscles of the hip joint to be reflected of the femur in order to access the hip joint. These muscles will be repaired back to their anatomical insertion site once the hip replacement has been performed. Patients requiring a posterior hip replacement will have minor mobility restrictions in the first three months after surgery to allow the short external rotator muscles to heal back to the femoral bone.
Some patients require custom implants to ensure accurate reconstruction of the hip joint. These patients will need to undergo further investigations such as CT or MRI scans in order to plan and design the patient specific implant. The implant is usually manufactured from Titanium using modern 3D printing technology.
The goals of surgical approach and implant selection are life long implant survival while minimizing the risk of adverse outcomes and maximizing functional performance.
I am a fellowship trained orthopaedic hip surgeon and I will provide you with the all the information required to make an informed decision. I will discuss with you my recommended surgical option that will enable the best possible outcome.