TPO aims to restore the normal position of the femoral head (ball) within the acetabulum (socket) without the constant movement/knocking which causes damage as outlined above. Since there is no technique that can “tighten” the hip (this will occur naturally as the dog matures) the only option is to tilt the cup over the head to allow “capture”
The procedure involves cutting the pelvis (osteotomy) at three locations to allow the cup segment to be rotated to cover the femoral head by a calculated amount (usually 20-30 degrees). A specially designed plate is then applied to the side of the pelvis secured with screws to stabilise the cut bone. The pelvis is allowed to heal in this new position. Cartilage damage is therefore prevented and development of osteotarthritis dramatically slowed.
Occasionally, only one hip may a candidate for TPO with the HD in the other hip being managed successfully by conservative means. If both hips require TPO, then the procedures are can be staged 23 weeks apart. Salvage surgery (total hip replacement or excision arthroplasty) may be necessary on the hip that is not a candidate for
TPO due to progression of osteoarthritis TPO is a major surgical technique and not without potential complication, namely post-operative infection, problems with loosening of the plate and screws and possible intra-operative damage to the sciatic nerve. However, these issues are thankfully rare and careful candidate selection usually allows an excellent outcome in the majority of patients with a return to full, normal and pain-free exercise.