Choosing a hinged implant in the revision knee arthroplasty (rTKA) setting is challenging and limited data on implant performance exists. We present the survivorship and reason for failure in rTKA performed at our institution using the LINK hinge prosthesis, predominantly the cemented modular Endo-Model prosthesis. 260 consecutive revision knee cases performed between 2012 and 2020 were reviewed retrospectively. Mean follow up was 27 months (range 0 to 107). Survivorship was analysed in Stata using a Log Rank test to compare performance in patients stratified according to age (≥80 years old (76 cases), 70–79 years (104 cases) and ≤70 years (80 cases).Abstract
Introduction
Methodology
Opening wedge high tibial osteotomy (HTO) is an established surgical procedure for the treatment of early-stage knee arthritis. Other than infection, the majority of complications are related to mechanical factors – in particular, stimulation of healing at the osteotomy site. This study used finite element (FE) analysis to investigate the effect of plate design and bridging span on interfragmentary movement (IFM) and the influence of fracture healing on plate stress and potential failure. A 10° opening wedge HTO was created in a composite tibia. Imaging and strain gauge data were used to create and validate FE models. Models of an intact tibia and a tibia implanted with a custom HTO plate using two different bridging spans were validated against experimental data. Physiological muscle forces and different stages of osteotomy gap healing simulating up to six weeks postoperatively were then incorporated. Predictions of plate stress and IFM for the custom plate were compared against predictions for an industry standard plate (TomoFix).Objectives
Materials and Methods
The global economy has been facing a financial crisis. Healthcare costs are spiraling, and there is a projected £30 billion health funding gap by 2020 in the UK. What is happening in the UK is a reflection of a global problem. Rationing of healthcare is a topic of much discussion; as unless spending is capped, providing healthcare will become unsustainable. Who decides how money is spent, and which services should be rationed? In this article we aim to discuss the impact that rationing may have on orthopaedic surgery, and we will discuss our own experiences of attempts to ration local services.
This is the second of a series of reviews of registries. This review looks specifically at worldwide registry data that have been collected on knee arthroplasty, what we have learned from their reports, and what the limitations are as to what we currently know.
Mechanical alignment has been a fundamental tenet of total knee arthroplasty (TKA) since modern knee replacement surgery was developed in the 1970s. The objective of mechanical alignment was to infer the greatest biomechanical advantage to the implant to prevent early loosening and failure. Over the last 40 years a great deal of innovation in TKA technology has been focusing on how to more accurately achieve mechanical alignment. Recently the concept of mechanical alignment has been challenged, and other alignment philosophies are being explored with the intention of trying to improve patient outcomes following TKA. This article examines the evolution of the mechanical alignment concept and whether there are any viable alternatives.
Allogeneic blood transfusion is associated with complications and significant cost. The RD&E has looked at the use of autologous drains to decrease the frequency of allogeneic transfusion after our study of 100 cases showed an improved post-operative haemoglobin and reduced length of stay. In 2007 a protocol to identify those patients of increased need for an autologous drain was made using a study of 191 cases showed an average haemoglobin drop post-operatively of 3.05g/dl and average intra-operative blood loss of 285 ml. This protocol gave triggers for autologous drain use; preoperative haemoglobin of <13g/dl, intra-operative blood loss >400ml, tourniquet use, patient weight <50kg and patients refusing donated blood. In 2007-08, 65% of a further 275 cases analysed met the triggers for use of an autologous system. The remaining patients received low vacuum drains. Of the 275 patients, only 2 (<1%) of those who did not fulfil the criteria for an autologous drain required allogeneic blood, compared with 43 patients (24%) of those deemed high risk of transfusion, and assigned autologous drains. The protocol was successful in identifying those patients who required additional support and expenditure to minimise allogeneic blood transfusion. Analysis of this data led to recommended changes to the protocol in order to maximise the efficiency of the autologous drain use. Due to the increased cost of autologous drains (£68) compared with the low vacuum systems (£32), and the cost of allogeneic units at £141, the expenditure per patient was calculated and shown to fall from £92 in 2007 to £78 in a further patient cohort in 2010. In conclusion, this protocol allows the clinician to appropriately target the use of the more expensive autologous drains to those of increased risk of transfusion. This helps to minimise unnecessary allogeneic transfusion, and this has been shown to be cost effective.
