What Makes a Hip Replacement Complex? Simple vs Complex Hip Arthroplasty

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.

Earlier, international companies like Johnson, Stryker and Zimmer supplied all the revision and complex hip replacement implants, but they have since withdrawn much of their hardware because of government policies and duties. Luckily we now have two or three Indian companies that have come up very well and collaborated to produce cost-effective implants. Earlier a hip replacement used to cost around $10,000–$12,000; now that has come down to between $7,000 and $8,000. Where there are problems, I also try to reduce my own surgical fees to help the patient.

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.

A complex hip arthroplasty is a hip replacement made difficult by prior surgery, severe bone loss, deformity or instability. Recognising which cases fall into this category, rather than treating every hip replacement the same way, is the first step in planning a safe procedure.

In India, primary osteoarthritis of the hip is comparatively less common than in Western countries, African countries and other regions, though a significant number of complex cases still present for treatment. A large proportion of the more than 400 to 500 hip procedures performed each year involves complex rather than straightforward primary cases.

Complex hip arthroplasty requires thorough investigation of the cause of failure, careful physical examination, and imaging review before any decision is made, because pain alone is not enough reason to proceed with surgery. Identifying whether the underlying problem is instability, leg length discrepancy or a specific structural deficit is essential first.

Taking the necessary time to plan properly, rather than rushing into surgery, is central to a safe outcome in complex hip arthroplasty, since the reconstruction has to be matched to the specific structural problem found in each patient.