Finite element analysis is a computational technique to predict how different materials will react when a range of forces are applied. In the field of orthopedics, this technique has predominantly been used for implant design and testing. As the technology improves, increasing clinical applications are being developed, offering promise in the areas of surgical planning and the opportunity to tailor implants to individual patient characteristics. This article introduces the various preclinical mechanical tests available, as well as providing a brief overview of the finite element analysis technology.

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Medical and surgical research has always had a longstanding relationship with industry-based funding from sources, such as drug and device companies. Concerns exist surrounding the association between funding sources, outcome from studies and publication bias. Studies demonstrating increased odds ratios associated with positive results in industry sponsored studies across medicine have stimulated Cochrane reviews, literature reviews and other articles to examine this relationship further. In spine surgery in particular, studies with positive results have an odds ratio of 3.3 of being published. This article discusses the biases associated with industry sponsorship, possible ways to reduce such biases and ways to improve transparency in research relationships. This article explores the types of bias that can be encountered at different stages of research including previous trials in spine surgery. The means of improving transparency including the Physician Payment Sunshine Act of 2010 and International Committee of Medical Journal Editors (ICJME) accreditation are discussed. We recognize that physicians undertaking industry sponsored research should be protected and not be liable to perverse incentives. We conclude that mitigating bias in industry sponsored research is a multistep process and needs a multifaceted approach. The main beneficiary of research should be patients and as such a collective effort from medical professionals, health care institutions, journals and industry should approach research, and publications with that in mind.

Purpose Unicompartmental knee arthroplasty (UKA) provides patients with an alternative treatment to TKA in isolated medial compartment osteoarthritis providing better functional outcomes and faster recovery in the short term. Our aim was to quantify revision rates, predictors of revision, mortality rate and functionality of the Oxford Phase 3 UKA in a non-designer institution. Methods This was a retrospective review of prospectively collected regional registry data. All Oxford Phase 3 UKAs performed for medial tibio-femoral osteoarthritis of the knee joint were included from a single academic institution between the period of January 1st 2006 and December 30th 2009. Kaplan-Meier survivorship curves adjusting for loss to follow-up and deceased patients were generated. Primary outcome variables included all-cause and aseptic revision. Secondary outcome variables included functional outcome scores. Patients were reviewed at 6 months, 2 years, 5 years, 10 years and 15 years. Results A total of 64 cemented Oxford phase 3 UKAs were performed between January 2006 and November 2009. Fifteen-year follow-up data were available for 51 patients, of these 12 required revision. Survival rates, adjusting for patients that were either lost to follow-up or deceased, were 87.5% at 5 years, 81.4% at 10 years and 76.4% at 15 years. The overall aseptic revision rate at the time of review was 18.75% (n = 12). The only significant predictor of postoperative WOMAC score at 15 years was the preoperative WOMAC score (p = 0.03). Conclusion The Oxford Phase 3 UKA for medial tibio-femoral arthritis has promising outcomes at 15-year follow-up with a survival rate of 76.4% in a non-designer centre. Level of Evidence III.