Osteonecrosis or Avascular Necrosis of the Hip
Small vessels located in the Femoral Neck are responsible for supplying blood to the Femoral Head. When this blood flow stops, Osteonecrosis or Avascular Necrosis—the death of bone tissue—can occur, specifically in the Femoral Head. Whether permanent or temporary, if not resolved quickly, it can cause the femoral head to collapse and lead to hip Osteoarthritis.
A femoral neck fracture, hip dislocation, or even surgical trauma following an Arthroscopy can interrupt blood supply, leading to bone death.
Alcohol, steroids, hypertension, vasculitis, thrombosis, rheumatic diseases, and sickle cell anemia can also trigger this pathology.
Symptoms:
In the early stages, Osteonecrosis cannot be identified by sight alone; a Magnetic Resonance Imaging (MRI) is required. Once it reaches advanced stages, it typically causes pain in the groin and thigh, hip stiffness, and limited range of motion, and the patient may even begin to limp. There is no set timeline for its development; symptoms can appear suddenly or progressively.
Management:
Although the natural progression of this pathology is not yet fully defined, treatment is often based on the condition of the Femoral Head at the time of diagnosis and whether it has collapsed. If detected in early stages, various surgical non-prosthetic and non-surgical treatments are available to extend the life of the bone.
One such treatment is core decompression (drilling into the affected area) to reduce internal pressure and alleviate pain; another option is an Osteotomy, where a controlled bone fracture is made to reorient the Femoral Head so that a healthy area bears the weight and load.
Once collapse has occurred, the best alternative is a partial or total Hip Replacement depending on the case. This allows the patient to regain their quality of life and perform daily activities without pain.
