Total Elbow Replacement
History
The first commercially available Total Elbow Replacement system available in the UK for dogs was the Conzemius / IOWA state system which was became available around 2005. Here at the Royal Veterinary College, we invested in this technology, and performed a number of these procedures. In 2008, a second Total Elbow Replacement system called the TATE system became available.
The TATE elbow system is a cartridge press-fit implant that replaces the natural weight bearing surfaces of the elbow joint, and overcomes some of the surgical technical challenges of the Conzemius / IOWA state system. Here at the Royal Veterinary College, we have also invested in the TATE Total Elbow Replacement and early results are promising.
Suitable candidates for total elbow replacement
At the present time, total elbow replacement is limited to dogs with end-stage elbow osteoarthritis which is not responsive to medical management. These dogs have significant lameness and elbow pain despite treatment with pain killers such as non-steroidal anti-inflammatory drugs (NSAIDs -e.g. Rimadyl, Metacam, Previcox). 
End-stage elbow arthritis means when all other treatment options have been tried and failed. Therefore the surgery is generally performed when amputation of the limb or fusion of the elbow joint are the only other alternatives – however neither of these alternatives are very satisfactory treatment options. The reason that elbow replacement is only performed as a last resort is that the procedure is very much in its infancy and the longer term outcome with TATE Total Elbow Replacement appears to be good but is unproven. In addition, the surgery is difficult and possible complications are numerous and catastrophic.
With time, as our experience with elbow replacement develops and as the surgical technique evolves, it is likely that less severely affected dogs will be suitable candidates for elbow replacement. If the surgery fails or catastrophic complications are encountered, amputation may be the final result as a last resort.
Candidates for total elbow replacement must be in otherwise reasonably good health and must be free of active infection elsewhere in the body such as skin infection (dermatitis), ear infection (otitis) or dental disease (periodontitis).
TATE - The surgical procedure
The medial epicondyle of the humeral condyle (inner surface of the elbow joint) is removed with a saw. This exposes the elbow joint. A very precisely engineered set of instruments is used to determine the axes of the weight bearing bones from the elbow joint (humeral condyle, proximal radius and proximal ulna); subsequently bone is removed to allow the implant cartridge to fit.
Once this preparation is complete, the implant cartridge is inserted into the prepared hole in the bone. The cartridge is press fitted to the bone, and is designed such that the bone will grow into it and stabilise it. Once the cartridge is in place, the set-plate that locks it into position is removed and the cartridge is free to rotate hence enabling flexion and extension of the elbow joint.
The radius and ulna bones are fused together using a screw and bone graft, and the medial epicondyle of the humeral condyle is re-attached using two screws.
The cost of this surgery is currently £4000.
Complications
The complication rate for TATE total elbow replacement surgery is unknown. Possible complications include infection, luxation (dislocation), fractures or implant loosening. If a significant complication were to occur that were not responsive to treatment, amputation is the fall back option – it might be possible to attempt fusion of the elbow joint but given the amount of bone that has been removed and the nature of the implant, this is unlikely to be successful.