More & more young & active patients world wide are in need of hip replacement surgery. In such cases, it is imperative to pay special attention to the technique to ensure a successful outcome & longevity of the operation. Traditionally a total hip replacement was performed in the older age group. Young patients with hip pain either had to endure pain or subject themselves to a total hip replacement with its inherent disadvantages of dislocation and life span of 10 to 15 years. Now, recent advances in bio- materials and techniques have made it possible for young patients to get a satisfactory & successful outcome after a hip arthroplasty. Definition of a young patient - The deciding factor is not necessarily the patient's age, but their activity level. Even many older patients like to play Tennis, Golf or participate in physical activity. This applies also to anyone who can be expected to live for a long time, is biologically (not chronologically) young and has good bone quality.
Today even septuagenarians meet these pre requisites. Surgeons have to re think their conventional strategy of putting in a total hip with a metal on poly bearing. Resurfacing also poses several un answered questions and cannot be considered as a panacea. Causes leading to hip pain in young patients- Avascular necrosis is the leading cause leading to hip arthritis followed by developmental dysplasia of the hip.
Perthes disease, slipped upper femoral epiphyses, sickle cell disease and post traumatic arthritis are other causes leading to the common outcome of secondary osteo-arthritis . In middle and older Caucasian patients, Primary osteoarthritis is the commonest cause of hip pain. Limitations of hip resurfacing Off late, hip resurfacing has been vigorously promoted on the internet as a possible & preferred treatment. However there are some inherent un answered problems with hip resurfacing. Elevated metal ion levels, metal allergy, metallosis are some of the side effects of metal on metal hip resurfacing. The long term impact of raised metal ion levels is unknown. Females in all age groups are high risk candidates because of the risk of fertility curbs in young & femoral neck fracture in the older.
However the attraction of a hip resurfacing drives many females to ignore these risks and choose a hip resurfacing. Dr.Venkatchalam discusses an alternate bone sparing safe approach in young & active patients. These approaches combine the advantages of a hip resurfacing and total hip replacement. Why do you prefer the short stem ? The various short stem prostheses like the Proxima hip & METHA combine the advantages of resurfacing & THR. On the acetabular side a full range of options is available to the surgeon.
The force transfer in the femur is more proximal and more biological. Lack of a distal stem component eliminates the incidence of thigh pain. In addition these implants open up the vast range of bio materials available. All bio-material combinations like metal on metal, metal on poly, ceramic on poly, ceramic on ceramic are possible. These promise excellent longevity. If a revision becomes necessary, then one can switch to a standard stem. Some of these models like the METHA hip make it possible for the surgeon to tailor the implant to the individual's anatomy. What other innovations can you use to ensure a proper implant positioning?
Navigation allows the surgeon to place the implant in the optimal position. What are the special considerations in Asian patients? Dysplasia and osteo necrosis constitute the most common indications for total hip replacement in India & Asia. Primary osteo-arthritis is rare. Moreover these patients are younger and more active. Their social and religious habits such as sitting with crossed legs dictate to the surgeon that he must use a prosthesis which provides a large range of movement. Risk of dislocation has to be reduced.
Anatomic differences also exist. All these variables require a special implant concept and very wear resistant materials with a large diameter. To summarize, treatment of hip arthritis in the young poses a challenge to surgeons and scientists. Hip resurfacing while offering a possible solution has some draw backs. Short stem prostheses with newer bio materials promise to overcome these deficiencies and offer a long lasting surgical outcome.
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