Complex Hip Arthroplasty

It depends on the pathology and on the activity — for example, Andy Murray, the tennis player, had a hip replacement and could carry on with most of his activities, though one cannot guarantee 100%. If someone has had a total hip replacement, high-impact sports of that kind are generally not advisable — but they can change to a different sport. If the condition is femoroacetabular impingement (FAI) rather than arthritis, we do hip arthroscopy to remove the impingement, clean the cartilage, and inject stem cell therapy; the hip regenerates over about 6 months and results on repeat MRI are often excellent. Most sport-related damage is to ligaments or cartilage, not true hip arthritis — hip arthritis itself means the cartilage is gone and the anatomy is deformed, which is a different issue, and after that kind of hip replacement patients feel great satisfaction just resuming daily activities.

We look at the X-ray to see whether the hip joint space is maintained. If pain has started but mobility is still there and the joint space and cartilage are maintained, we don't straight away advise hip replacement — we have other options, such as the arthroscopic method, where we clean up osteochondral extra bone formation or damaged cartilage and repair it with stem cell therapy. That is a good option instead of hip replacement. Once the cartilage is completely damaged on CT or MRI, with no blood flow to the femoral head, then the only answer is hip replacement.

For sickle cell disease in children, bone marrow transplant is the standard treatment, with the best results when done early while the patient is still a child — my colleague Dr. Dharma Choudhary's centre specialises in this. As for hip arthroplasty itself, it is not recommended below 17–18 years of age because the hip does not develop enough. Below that age we instead use arthroscopy to clean up damage, or osteotomies — we change the weight-bearing surface of the hip with procedures like valgus or varus osteotomy — based on where the MRI shows the main damage, which relieves pain much better.

After hip replacement, certain things are not recommended: sitting on the floor, sitting cross-legged, and squatting, as these positions can damage the implant and cause loosening. High-energy sport activity should also be avoided. Following these recommendations, a well-fitted hip can last 30–35 years, and since most hip replacement candidates are of an older age profile, most patients will not need it again in their lifetime.

Stem cells are osteoprogenitor or osteopotent cells that can convert into osteoblasts, osteoclasts, or chondroblasts. For hip cartilage damage, we clean the damaged islands of cartilage with hip arthroscopy and inject stem cells; over time, review MRIs show the cartilage growing back, like grass growing, with less damage and fewer symptoms after about 6 months — though it does take time. In orthopaedics we harvest stem cells from the iliac crest, using a Jamshidi needle, taking around 120 ml of blood from the marrow (posterior or anterior, near the spine). This is then put into a centrifuge machine for about 45 minutes to 1 hour to concentrate the stem cells before injection.

Complex hip arthroplasty describes cases made difficult by trauma, avascular necrosis, developmental dysplasia, failed previous implants, or severe bone loss. These cases require far more planning and a wider range of implant options than a standard primary hip replacement, and can take two to two and a half hours in the operating room compared with forty to forty five minutes for a straightforward case.

A straightforward primary hip replacement for simple osteoarthritis is typically completed in forty to forty five minutes. Complex or revision hip arthroplasty, needed for conditions such as post-traumatic arthritis, avascular necrosis, developmental dysplasia, aseptic loosening, infection, or severe bone loss, can take as long as two to two and a half hours.

Dr. Rakesh Mahajan, Vice Chairman and HOD of the Department of Orthopaedics at BLK-Max Super Speciality Hospital in New Delhi, performs the surgery. He has more than thirty years of experience and operates on four hundred to five hundred hips each year, a substantial share of which are complex cases.

Planning starts with identifying the actual underlying problem, such as instability, leg length discrepancy, or a specific area of bone loss, rather than treating pain alone as the reason for surgery. This involves physical examination, long film X-rays, AP pelvis and Judet views, and where needed, CT or 3D CT reconstruction to map out exactly what needs to be reconstructed.

Hip pathology is unusual in how completely it can limit a patient's daily life. Patients can often manage knee arthritis or degenerative spine disease reasonably well, but hip damage does not allow the same freedom of movement, and once the hip joint is damaged, locomotion becomes seriously affected.