1	ERASS CONGRESS LUND JUNE 3-5, 2004 COMPLICATIONS OF KNEE SURGERY IN JIA KJ Hamelynck
2	Complications of knee surgery in JIA Surgical interventions may be needed in the treatment of JIA to overcome the local complications of the disease surgical interventions have no influence on the disease it self
3	Complications of knee surgery in JIA Surgical interventions may be performed to correct contractures to treat synovitis to correct bony deformity to replace the knee joint Each intervention has its indication and complications
4	Complications of knee surgery in JIA Contractures should ideally be prevented by conservative means like exercises, dynamic splints, injections and gentle manipulation if correction is no longer possible by gentle manipulation, surgery is indicated rather than manipulation under anesthesia
5	Complications of knee surgery in JIA Contractures The risk of manipulation is fracture
6	Complications of knee surgery in JIA Contractures Contractures of the knee may be influenced by ipsilateral hip and foot disorders and even by deformities of the other side
7	Complications of knee surgery in JIA Contractures The most important question is to correct where and how ! Correction is not a straightforward procedure. Releases must be performed sequentially, step by step The risk : to create instability !!!
8	Complications of knee surgery in JIA Contractures Think about extra-articular cause for deformity Release of the superficial fascia in the fossa poplitea
9	Complications of knee surgery in JIA Synovectomy Is synovectomy indicated in JIA or not ? If not indicated, the intervention is already a complication by it self
10	Complications of knee surgery in JIA Synovectomy Synovectomy may cause unnecessary harm to the cartilage and the anterior cruciate ligament If the intervention is done through para-patellar incisions, the scars of these incisions may have a negative influence on wound healing when at a later stage total knee arthroplasty is performed.
11	Complications of knee surgery in JIA Synovectomy TKA 20 years after synovectomy > wound healing compromised > infection > arthrodesis !!!
12	Complications of knee surgery in JIA Osteotomy osteotomy of the tibial head may be performed to correct flexion deformity
13	Complications of knee surgery in JIA Osteotomy The negative effect on TKA in the future must not be underestimated Probably a new osteotomy must be carried out to correct the deformity again.
14	Complications of knee surgery in JIA Total knee arthroplasty TKA in JIA may be compromised by soft tissue problems : contractures and laxities bone problems : defects, subchondral cysts, osteopenia cq osteoporosis
15	Complications of knee surgery in JIA Total knee arthroplasty TKA in JIA may be compromised by skin may be thin sizing of components not always clear patella replacement needed ?
16	Complications of knee surgery in JIA Total knee arthroplasty The bone in JIA may be extremely soft, which may hardly be noticed on standard x-rays
17	Complications of knee surgery in JIA Total knee arthroplasty The answer to bone loss or soft bone is NOT the use of bone cement The answer is re-inforcement of bone by transplantation of bone
18	Complications of knee surgery in JIA Total knee arthroplasty Condyles of the femur and the tibia may be hyper- or hypo- plastic causing valgus- or varus-malalignment
19	Complications of knee surgery in JIA Total knee arthroplasty There also is considerable doubt about the quality of ligaments For that reason surgeons may consider the implantation of prostheses that are intrinsically constraint
20	Complications of knee surgery in JIA Total knee arthroplasty When a prosthesis with intrinsic constraint is chosen, that choice may be incorrect most of the rotational and shear forces will now be conducted directly to the bone-prosthesis interface > mechanical loosening is likely to occur Remember : the bone is soft
21	Complications of knee surgery in JIA Total knee arthroplasty
22	Complications of knee surgery in JIA Total knee arthroplasty Over-release must be prevented, as these knees will certainly become unstable The surgeon should carefully investigate the true nature of the contracture
23	Complications of knee surgery in JIA Total knee arthroplasty The most important limiting structure may well be found outside the joint : the posterior superficial fascia
24	Complications of knee surgery in JIA Total knee arthroplasty Cleaning the posterior compartment of the knee may be far more important than performing a release
25	Complications of knee surgery in JIA Summary Surgery in JIA is performed to correct contractures and bony deformity, to treat synovitis and to replace the knee The correction of contractures may be difficult and should never result in instability
26	Complications of knee surgery in JIA Summary Surgery is compromised by the poor quality of bone. The answer should be to re-inforce bone by transplantation When prostheses are implanted, prostheses with free anatomical motion relieving the stresses from the interface are preferred.
27	Complications of knee surgery in JIA How do I know ? Because I have made all mistakes that were demonstrated The dubious name for that is experience and the man having this experience is called expert !!