Revision THR (Case examples)

Revision arthroplasty is a reconstructive surgery of the hip joint and is done when primary surgery (total hip arthroplasty) fails.

The  indications for revision hip arthroplasty are

Infection

Dislocation as a consequence of mal-position of the components

Loosening of the components

Infection is evaluated by blood tests and tests such as MRI scan, Technetium bone scan are performed.

If the infection is detected early then a simple washout would be successful in most of the cases.
However if the infection is severe then either a single stage or two staged revision would be indicated.

In a single stage revision  for infection all the artificial components are removed, all the unhealthy tissue excised and a set of new components are inserted in the same sitting. The success rate of a single state revision for infection is around 70%.

In a two-stage revision for infection the implants are removed and temporary antibiotic loaded cement spacer is placed; the final components are inserted later on after a gap of at least 6 weeks. The patients would be on appropriate antibiotics during this period. The success rate for two-staged revision is around 90%.

If the components are not in optimal position and it is repeatedly dislocating, then a revision surgery should be performed to stabilize the hip joint.

Aseptic loosening of the primary total hip arthroplasty means the loosening of the components, which occurs without any infection. This may take between 15 to 25 years depending on various factors. This is how ultimately the primary surgery fails.

The loosening occurs because of the wear particles generated by the artificial bearing surfaces.

The surgeon could use bone harvested from patient, or from bone bank. One could also use special material such as trabecular metal made out of tantalum.