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Aseptic loosening of orthopaedic implants is precipitated by wear debris-induced osteolysis. Central to this process are the proinflammatory mediators that are produced in response to wear by the fibroblastic cells, which comprise the majority of periprosthetic membranes. Since this pro-inflammatory cascade is mediated by a plethora of factors with redundant functions, it is imperative to establish a hierarchy. Two well-known fibroblast derived pro-inflammatory factors that stimulate wear debris-induced osteoclastic resorption are prostaglandin E2 (PGE2) and IL-6. However, their relationship to each other in this process is poorly defined. Here we show immunohistochemistry of retrieval membranes indicating that COX-2 is the principal cyclooxygenase responsible for PGEZ production in fibroblasts around failed implants. We also performed in vitro experiments with fibroblasts derived from wild-type (WT), COX-I (-/-) and COX-2 (-/-) mice, which demonstrated that COX-2 is required for Ti wear debrisinduced PGEZ production. Interestingly, COX-2 was also required for IL-6 production in these assays, which could be rescued by the addition of exogenous PGE2 (lo-' M). Pharmacology studies that utilized the COX-1 selective inhibitor SC 560, the COX-2 selective inhibitor celecoxib, and the nonselective COX inhibitor indomethacin confirmed these results. Taken together, these results indicate that selective inhibition of prostaglandin signaling could favorably impact aseptic loosening beyond its direct effects on PGE2 synthesis, in that it inhibits downstream pro-inflammatory/pro-osteoclastic cytokine production.

We have treated 22 patients with an elbow contracture using a static progressive turnbuckle splint for a mean of 4.5 ± 1.8 months. All had failed to improve with supervised physiotherapy and splinting. The mean range of flexion before splintage was from 32 ± 10° to 108 ± 19° and afterwards from 26 ± 10°( p = 0.02) to 127 ± 12° (p = 0.0001). A total of 11 patients gained a 'functional arc of movement,' defined as at least 30° to 130°. In eight patients movement improved with turnbuckle splinting, but the functional arc was not achieved. Six of these were satisfied and did not wish to proceed with surgical treatment and two had release of the elbow contracture. In three patients movement did not improve with the use of the turnbuckle splint and one subsequently had surgical treatment.Our findings have shown that turnbuckle splinting is a safe and effective treatment which should be considered in patients whose established elbow contractures have failed to respond to conventional physiotherapy.

We have treated 22 patients with an elbow contracture using a static progressive turnbuckle splint for a mean of 4.5 +/- 1.8 months. All had failed to improve with supervised physiotherapy and splinting. The mean range of flexion before splintage was from 32 +/- 10 degrees to 108 +/- 19 degrees and afterwards from 26 + 10 (p = 0.02) to 127 +/- 12 degrees (p = 0.0001). A total of 11 patients gained a 'functional arc of movement,' defined as at least 30 degrees to 130 degrees. In eight patients movement improved with turnbuckle splinting, but the functional arc was not achieved. Six of these were satisfied and did not wish to proceed with surgical treatment and two had release of the elbow contracture. In three patients movement did not improve with the use of the turnbuckle splint and one subsequently had surgical treatment. Our findings have shown that turnbuckle splinting is a safe and effective treatment which should be considered in patients whose established elbow contractures have failed to respond to conventional physiotherapy.

The goal of this study was to define the anti-osteoclastogenic and/or anti-inflammatory role of IL-6 in inflammatory bone resorption using in vivo and in vitro methods. To this end, titanium particles were placed on murine calvaria, and bone resorption and osteoclast formation quantified in wildtype and IL-6 -/-mice. In this model, calvarial bone loss and osteoclast formation were increased in titanium-treated IL-6 -/-mice. Although basal numbers of splenic osteoclast precursors (OCP) were similar, IL-6 -/-mice treated with particles in vivo had increased splenic OCP suggesting an enhanced systemic inflammatory response. In vitro osteoclastogenesis was measured using splenic (OCP) at various stages of maturation, including splenocytes from WT, IL-6 -/-and TNFα transgenic mice. ELISA was used to measure TNFα production. IL-6 inhibited osteoclastogenesis in early OCP obtained from wild-type and IL-6 -/-spleens. Pre-treatment of OCP with M-CSF for three days increased the CD11b high /c-Fms+ cell population, resulting in an intermediate staged OCP. Osteoclastogenesis was unaffected by IL-6 in M-CSF pre-treated and TNFα transgenic derived OCP. IL-6 -/-splenocytes secreted greater concentrations of TNFα in response to titanium particles than WT; addition of exogenous IL-6 to these cultures decreased TNFα expression while anti-IL-6 antibody increased TNFα. While IL-6 lacks effects on intermediate staged precursors, the dominant in vivo effects of IL-6 appear to be related to strong suppression of early OCP differentiation and an anti-inflammatory effect targeting TNFα. Thus, the absence of IL-6 results in increased inflammatory bone loss.

The Symetis Acurate TA device demonstrates high procedural success and excellent acute and 1-year patient outcomes. The device allows safe implantation in patients at higher risk for coronary artery obstruction.