Osteonecrosis

Osteonecrosis (avascular necrosis, AVN) is the death of bone tissue from loss of blood supply. It most commonly affects the hip (femoral head), but can involve the knee, shoulder, ankle, or jaw. If left untreated, the bone collapses, destroying the joint. In India, AVN of the hip is a particularly common cause of severe hip arthritis in younger adults.

Common causes in India

• High-dose or prolonged steroid use — including unregulated injectable or oral steroids sometimes given as "quick fix" injections.
• Heavy alcohol use.
• Sickle cell disease.
• Previous hip trauma/dislocation.
• Decompression sickness (diving).
• Autoimmune conditions (lupus, others).
• Pregnancy-related — uncommon.
• Chemotherapy, radiation.
• HIV, high cholesterol, organ transplantation.
• Idiopathic — no identifiable cause.
• COVID-19 and its high-dose steroid treatment led to a visible rise in post-COVID AVN cases in Indian orthopaedic centres (2020-22).

Symptoms

• Groin, thigh, or buttock pain — worse on bearing weight, on motion.
• Progressive pain, limp, limited range of motion over months.
• Early AVN can be asymptomatic — picked up on imaging.
• Knee AVN — knee pain with activity; shoulder AVN — pain on lifting.

Diagnosis

MRI is the best test — detects AVN at the earliest stage, before X-ray changes. X-ray shows later disease. Staging (Ficat, ARCO) guides treatment.

Treatment — depends on stage

• Early (pre-collapse) — protect weight bearing, treat cause (stop steroids where possible, treat sickle cell, stop alcohol). Core decompression (surgical drilling) reduces pressure, can delay progression.
• Bone grafts, stem-cell augmented core decompression, osteotomy — in selected early cases.
• Later (post-collapse) — joint replacement (hip, knee, shoulder) is the definitive treatment.
• Medicines (bisphosphonates, vasodilators) — adjunctive; mixed evidence.
• Treat underlying drivers aggressively to prevent new sites.

Prevention — India focus

• Never take unprescribed steroid injections — from unregulated practitioners, ayurvedic adulterations, or unsupervised self-use.
• When steroids are medically needed, use the lowest dose for the shortest time under Health Expert supervision.
• Moderate or no alcohol.
• Sickle cell disease — early diagnosis + treatment + joint surveillance.
• Any new persistent hip or groin pain — don't ignore; early MRI changes outcomes.