Hip Joint Replacement - Expectation and Limitations

Hip Joint Replacement is a surgery commonly performed in Orthopedic practice, wherein the hip joint is changed to a new modular bearing providing painless articulation.

The common indications of a Hip Replacement surgery are:
1. Hip Joint Arthritis- either degenerative or inflammatory pathology.
2. Fracture Neck Femur (upper end of thigh bone)
3. Malformed hip Joint- a disease of the childhood
4. Loss of blood supply (Avascular Necrosis)

The definite indication of Hip Replacement is - Painful hip joint with radiological evidence of obliteration of joint space. Only exclusion is Fracture Neck Femur; wherein a partial change of the bearing component may be performed.

Patients usually have a number of queries regarding;
a) Will the pain go?
b) How much time do I need to stay in Hospital; and how much time off work?
c) Do I need to come back again for a possible surgery?
d) What happens to the metal inside my body?
e) What precautions I need to take, and for how long?

I will try to offer explanations to every question one by one...

The foremost concern is PAIN.
After a hip replacement, the pain due to arthritis usually subsides in 4-6 weeks. Thereafter, there may be occasional reminders of pain after unaccustomed activity. If however, the pain re-appears after a prolonged pain free period; or the pain tends to worsen progressively, there is a definite cause for concern. This requires an urgent evaluation by the Orthopedic surgeon.

As regards hospital stay, the usual duration is 1 week. The timing of going back to previous level of activity depends upon the type of Hip replacement - Cemented/ Un-cemented; and the quality of bone stock. Usually patients may resume office and sedentary work after 4-6 weeks.

The typical longevity of a Hip replacement depends upon- quality of bone/ level of physical activity/ Age/ body weight/ technique of surgery. Most hip replacements survive an average of 15-20 years. However, a large number of variables affecting longevity prevents accurate survival analysis.

The metal typically used in a Hip Replacement is non - reacting to body fluids. It may be Stainless Steel/ Titanium alloy, Cobalt - chrome alloy. The bearing surface is important factor in survival. Ceramic-on Ceramic and Metal-on Metal the the favored ones in current practice.

The most important of all, are the precautions to be taken by the patient himself. Dislocation of the new joint is a potential risk. extremes of movements should be avoided under all circumstances.

To summarize, it is important to understand the advantages/ limitations of a Hip replacement and to expect a reasonable goal before undergoing surgery. In a properly selected patient, it offers significant improvement in the quality of life and activity level.

The discussion on the relative performance of different bearing surfaces in hip replacement, will be discussed in subsequent posts.