Total ankle replacement: why, when and how?
(3/23)
Total ankle replacement (TAR) was first attempted in the 1970s, but poor results led to its being considered inferior to ankle fusion until the late 1980s and early 1990s. By that time, newer designs which more closely replicated the natural anatomy of the ankle, showed improved clinical outcomes. Currently, even though controversy still exists about the effectiveness of TAR compared to ankle fusion, TAR has shown promising mid-term results and should no longer be considered an experimental procedure. Factors related to improved TAR outcomes include: 1) better patient selection, 2) more precise knowledge and replication of ankle biomechanics, 3) the introduction of less-constrained designs with reduced bone resection and no need for cementation, and 4) greater awareness of soft-tissue balance and component alignment. When TAR is performed, a thorough knowledge of ankle anatomy, pathologic anatomy and biomechanics is needed along with a careful pre-operative plan. These are fundamental in obtaining durable and predictable outcomes. The aim of this paper is to outline these aspects through a literature review. (+info)
Use of a trabecular metal implant in ankle arthrodesis after failed total ankle replacement.
(4/23)
Although ankle arthrodesis has been considered the gold standard for treatment of symptomatic end stage arthritis, recent improvements in arthroplasty designs and instrumentation have led to a resurgence in interest in ankle arthroplasty. While first generation arthroplasty systems had high failure rates due to cemented techniques or highly constrained designs, newer generations of ankle replacements have introduced more anatomic and pressfit techniques. Early results have been promising, with improved functional outcomes versus ankle arthrodesis. However, complication rates are still substantial, and the procedure should be restricted to properly indicated patients. Long-term follow-up studies are necessary, but total ankle arthroplasty has become a viable option for surgical treatment of ankle arthritis. (+info)
Meta-analysis of unexpected findings in routine histopathology during total joint replacement.
(6/23)
BACKGROUND: Routine histopathological analysis of bone extracted during total joint replacement is controversial. OBJECTIVES: To evaluate the utility of routine histopathological analysis in total joint replacement. METHODS: We calculated the risk for discrepant diagnosis between the pre- and postoperative histopathological results by performing a meta-analysis of 11 studies (including our data). We also calculated the risk for significant discrepancies. RESULTS: The discrepant diagnoses analysis showed a random effect of 3% discrepancies (95% confidence interval 1.2-3.7%). Funnel plot indicates a publication bias; consequently, the conclusions from this analysis should be interpreted with caution. Regarding the significant discrepancy in diagnosis, we performed a meta-analysis of nine studies. Fixed-effects analysis of all the studies resulted in 0.16% significant discrepancies (95% CI 0.02-0.30%) with no heterogeneity (Q = 3.93, degrees of freedom = 9, P = 0.14, /2 = 49.2%), and appropriate fixed-effects models. CONCLUSIONS: We recommend no further routine histological examination, reserving this tool for cases with a controversial primary diagnosis and unexpected findings during the operation. (+info)
Numerical simulation of strain-adaptive bone remodelling in the ankle joint.
(7/23)