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
The James Lind Alliance aims to bring patients, carers, and clinicians together to identify uncertainties regarding care. A Priority Setting Partnership was established by the British Association for Surgery of the Knee in conjunction with the James Lind Alliance to identify research priorities related to the assessment, management, and rehabilitation of patients with persistent symptoms after knee arthroplasty. The project was conducted using the James Lind Alliance protocol. A steering group was convened including patients, surgeons, anaesthetists, nurses, physiotherapists, and researchers. Partner organizations were recruited. A survey was conducted on a national scale through which patients, carers, and healthcare professionals submitted key unanswered questions relating to problematic knee arthroplasties. These were analyzed, aggregated, and synthesized into summary questions and the relevant evidence was checked. After confirming that these were not answered in the current literature, 32 questions were taken forward to an interim prioritization survey. Data from this survey informed a shortlist taken to a final consensus meeting.Aims
Methods
Our aim was to compare kinematic with mechanical alignment in
total knee arthroplasty (TKA). We performed a prospective blinded randomised controlled trial
to compare the functional outcome of patients undergoing TKA in
mechanical alignment (MA) with those in kinematic alignment (KA).
A total of 71 patients undergoing TKA were randomised to either
kinematic (n = 36) or mechanical alignment (n = 35). Pre- and post-operative
hip-knee-ankle radiographs were analysed. The knee injury and osteoarthritis
outcome score (KOOS), American Knee Society Score, Short Form-36,
Euro-Qol (EQ-5D), range of movement (ROM), two minute walk, and timed
up and go tests were assessed pre-operatively and at six weeks,
three and six months and one year post-operatively.Aims
Patients and Methods
A small proportion of patients have persistent
pain after total knee replacement (TKR). The primary aim of this study
was to record the prevalence of pain after TKR at specific intervals
post-operatively and to ascertain the impact of neuropathic pain.
The secondary aim was to establish any predictive factors that could
be used to identify patients who were likely to have high levels
of pain or neuropathic pain after TKR. A total of 96 patients were included in the study. Their mean
age was 71 years (48 to 89); 54 (56%) were female. The mean follow-up
was 46 months (39 to 51). Pre-operative demographic details were
recorded including a Visual Analogue Score (VAS) for pain, the Hospital
Anxiety and Depression score as well as the painDETECT score for neuropathic
pain. Functional outcome was assessed using the Oxford Knee score. The mean pre-operative VAS was 5.8 (1 to 10); and it improved
significantly at all time periods post-operatively (p <
0.001):
(from 4.5 at day three to five (1 to 10), 3.2 at six weeks (0 to
9), 2.4 at three months (0 to 7), 2.0 at six months (0 to 9), 1.7
at nine months (0 to 9), 1.5 at one year (0 to 8) and 2.0 at mean
46 months (0 to 10)). There was a high correlation (r >
0.7; p <
0.001) between the mean VAS scores for pain and the mean painDETECT
scores at three months, one year and three years post-operatively.
There was no correlation between the pre-operative scores and any
post-operative scores at any time point. We report the prevalence of pain and neuropathic pain at various
intervals up to three years after TKR. Neuropathic pain is an underestimated
problem in patients with pain after TKR. It peaks at between six
weeks and three-months post-operatively. However, from these data
we were unable to predict which patients are most likely to be affected. Cite this article:
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.
Clinical experience of impaction bone grafting for revision knee arthroplasty is limited, with initial stability of the tibial tray emerging as a major concern. The length of the stem and its diameter have been altered to improve stability. Our aim was to investigate the effect of the type of stem, support of the rim and graft impaction on early stability of the tray. We developed a system for impaction grafting of trays which we used with morsellised bone in artificial tibiae. Trays with short, long thick or long thin stems were implanted, with or without support of the rim. They were cyclically loaded while measuring relative movement. Long-stemmed trays migrated 4.5 times less than short-stemmed trays, regardless of diameter. Those with support migrated 2.8 times less than those without. The migration of short-stemmed trays correlated inversely with the density of the impacted groups. That of impaction-grafted tibial trays was in the range reported for uncemented primary trays. Movements of short-stemmed trays without cortical support were largest and sensitive to the degree of compaction of the graft. If support of the rim was sufficient or a long stem was used, impacted morsellised bone graft achieved adequate initial stability.
