Aims

Achievement of accurate microbiological diagnosis prior to revision is key to reducing the high rates of persistent infection after revision knee surgery. The effect of change in the microorganism between the first- and second-stage revision of total knee arthroplasty for periprosthetic joint infection (PJI) on the success of management is not clear.

Aims

The primary aim of our study was to assess the influence of age on hip-specific outcome following total hip arthroplasty (THA). Secondary aims were to assess health-related quality of life (HRQoL) and level of activity according to age.

Aims

The aim of this study was to assess the quality of life of patients on the waiting list for a total hip (THA) or knee arthroplasty (KA) during the COVID-19 pandemic. Secondary aims were to assess whether length of time on the waiting list influenced quality of life and rate of deferral of surgery.

Aims

The primary aim is to estimate the current and potential number of patients on NHS England orthopaedic elective waiting lists by November 2020. The secondary aims are to model recovery strategies; review the deficit of hip and knee arthroplasty from National Joint Registry (NJR) data; and assess the cost of returning to pre-COVID-19 waiting list numbers.

Aims

The primary aim was to assess the rate of patient deferral of elective orthopaedic surgery and whether this changed with time during the coronavirus disease 2019 (COVID-19) pandemic. The secondary aim was to explore the reasons why patients wanted to defer surgery and what measures/circumstances would enable them to go forward with surgery.

Aims

Stiffness is a common complication after total knee arthroplasty (TKA). Pathogenesis is not understood, treatment options are limited, and diagnosis is challenging. The aim of this study was to investigate if MRI can be used to visualize intra-articular scarring in patients with stiff, painful knee arthroplasties.

Objectives

Our primary aim was to describe migration of the Exeter stem with a 32 mm head on highly crosslinked polyethylene and whether this is influenced by age. Our secondary aims were to assess functional outcome, satisfaction, activity, and bone mineral density (BMD) according to age.

The National Institute for Health and Clinical Excellence (NICE) has thus far relied on historical data and predominantly industry-sponsored trials to provide evidence for venous thromboembolic (VTE) prophylaxis in joint replacement patients. We argue that the NICE guidelines may be reliant on assumptions that are in need of revision. Following the publication of large scale, independent observational studies showing little difference between low-molecular-weight heparins and aspirin, and recent changes to the guidance provided by other international bodies, should NICE reconsider their recommendations?

Cite this article: Bone Joint Res 2014;3:146–9.

Purpose

Little information is available relating to patient demographics, reasons for failure and types of implants used at time of revision following failure of patellofemoral joint (PFJ) replacement.

Statement of purpose: To evaluate survivorship and knee function in patients who have undergone Kinematic Condylar Total Knee Replacement at a minimum of 15 years.

Methods: We evaluated all patients undergoing primary cemented TKR with the Kinematic Condylar implant (Howmedica), between January 1981 and December 1988. All operations were performed by a single surgeon through a medial parapatellar approach, with sparing of the PCL, all cemented and no patellae resurfaced.

Operation notes were analysed to confirm the type of procedure, underlying diagnosis, and thickness of tibial insert. Information was derived from patient records and postal questionnaire to all surviving patients, which included: WOMAC, SF-36, satisfaction scale and history of revision surgery.

Results: We have identified a total of 804 consecutive cases, 185 of these were bilateral giving a total of 619 patients. Mean age at implantation was 66 (range 17 to 83), with female:male ratio of 3:1. The underlying diagnosis was Osteoarthritis in 49%, and Rheumatoid Arthritis in 51% of patients.

As at September 2003 there were 153 patients (25%) still alive, using revision as an endpoint survivorship was 59.3% at a mean time since implantation of 17 years 8 months. Pain and function portions of the WOMAC questionnaire revealed mean scores of 37 and 47 out of 100.

Conclusion: This cohort has been shown to have 92% implant survivorship at ten years. We have shown that the survivorship deteriorates significantly between 10 and 17 years. Functional and pain scores after 17 years for patients with surviving implants were poor.

Survival was significantly better in females, no effect from pre-operative diagnosis was seen. 73% of these patients had 6mm tibial inserts, we postulate that the deterioration in survival is related to accelerated poly-ethylene wear beyond 10 years.

Statement of purpose: To study the biology of tendon – bone integration in human hamstring tendon autograft at the femoral tunnel interface

Methods: A total of 70 patients undergoing revision anterior cruciate surgery for both traumatic and atraumatic injury were studied. All surgery was performed under the supervision of the senior author. At time of surgery tissue was taken from the residual graft and femoral tunnel. The demographics of the original surgery, mechanism of failure, patient characteristics were recorded. We have also recorded variables such as tunnel positioning, early rehabilitation, associated ligamentous laxity. Local ethical committee approval has been granted. The specimens were analysed for gross evidence of cell necrosis, macrophage and fibroblast ingrowth (H& E). Vascularity was quantified by multiple high powered field counting. The influence of makers of cell turnover and matrix degradation have been determined by cell staining for TIMP-1, -2 and –3 (Immunohistochemistry) and early correlations drawn between the histological findings and patient factors such as mechanism of reinjury. We have also examined the graft expression of receptors of IGF1, FGF, MMP-1, 7, 8, 11, and 13 as key markers of collagen remodelling.

Results: We have found novel expression of MMP-13 in collagen graft tissue. There is clear evidence in a subgroup of certain patients exhibiting aggressive vascular ingrowth in association with IGF and MMP-11 and −13 expression suggesting a possible regulatory process. Areas of poor cellularity appear to exhibit low levels of MMP-13 but moderate levels IGF-II suggesting an alternative cellular response to graft fixation at the femoral tunnel. There appear to be distinct subgroups of cellular response in patients with atraumatic failure.

Conclusion: This is the first study to the biology of ACL graft failure at the bone tendon interface in a human model. Previous work has been case reports or using a canine model. These have limited application to the clinical work. We have found clear evidence of a processs of graft – host bone integration through neovascularisation. There is evidence of the graft remodelling through local expression of collagen resorptive agents. This work is being extended to look at the role of exogenous factors in augmenting graft integration at the host site.

J Bone Joint Surg Am. 1993 Dec;75(12):1795–803.

Am J Sports Med. 2001 Nov–Dec;29(6):689–98.

Methods Mol Biol. 2001;151:389–97.

Statement of purpose: We studied anterior knee function in a cohort of patients with either osteoarthritis or rheumatoid disease who had undergone knee replacement in a single unit using a standard implant.

We identified a consecutive series of patients who had undergone knee replacement surgery for either osteoarthritis or rheumatoid disease between 1990 and 1995 under the care of a single surgeon using the same implant and surgical technique. There were ninety patients in each group. All were examined and underwent radiography of the anterior compartment. Data was collated for Hospital for Special Surgery (HSS) score, Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) score, a specific patellar score and a Visual Analog score (VAS).

Results: There were no discernible differences between the rheumatoid and osteoarthritis groups in all the measured scores, with good anterior knee function noted in both.

Conclusion: Based on our outcome studies in a matched group of patients no differences were found for anterior knee function between osteoarthritis or rheumatoid disease. We do not routinely resurface the patella and do not consider there to be any particular indication for such in the rheumatoid disease patient.

There is little data on the long-term outcome of rotating hinge total knee arthroplasty. We provide a clinical and radiographic assessment of survivorship of the Kinematic rotating hinge total knee arthroplasty (How-medica, Rutherford, NJ), in a series of 72 implants, performed by a single surgeon in one unit, between 1983 and 1997. Survival analysis using known all cause revision revealed a 92% five-year implant survival, but worst-case scenario was 31% at five years.

In a subset of 27 patients we used the Nottingham Health Profile (NHP) to assess prospectively the changes in health-related quality of life following rotating hinge arthroplasty. In this salvage arthroplasty setting we demonstrate a significant improvement in two modalities of the NHP (pain and physical mobility).

Introduction: Arthroscopic A.C.L. reconstruction using Semitendinosus (S.T.) and Gracilis (Gr.) tendons is a popular technique for the treatment of ACL deficient knees. It is common to find accessory tendinous bands (vinculae) arising from these two tendons when harvesting them. The implications are that extra care must be taken with the use of the tendon stripper if one is to avoid cutting the main tendon. Our clinical experience reveals that these connections are highly variable and, contrary to popular thinking, may be present beyond 10cm. proximally.

Aim: Our aim was to map these intertendinous connections and assess their variability using a cadaveric model. In particular we were interested to identify the presence of vinculae arising proximally beyond 10cm.

Procedure: We dissected the tendons of Gr. and S.T. of ten embalmed adult human cadaveric legs. Various vinculae from both tendons were identified and their origin and insertion mapped. All measurements were done using the tibial crest as a reference.

Results: We found that vinculae have a high variability. Bands were seen between tendons, connecting them to the popliteal fascia, sartorius, gastrognemis, pretibial and superficial fascia. Vinculae originated more than 10cm proximally from Semitendinosus and Gracilis in eight and two occasions respectively. There was a constant connection band between S.T. and the grastrocriernius fascia.

Conclusion: Our results confirm that vincular anatomy is more variable than previously reported. Surgeons should be aware of our new finding of vinculae commonly originating beyond 10cm. proximally. This work has prompted us to investigate the role of MRI for pre-operatively templating vinculae.

Purpose: To study the effect of retaining an abraded femoral component on the outcome of primary revision of uncemented total knee prosthesis.

Method: 66 revision procedures for failed uncemented porous coated anatomic (PCA) total knee replacement were performed in 60 patients. At review, four patients had died while two were lost to follow up, therefore 60 knees in 54 patients were included in this prospective study. The principal indications for primary revision were polyethylene wear and loosening of the tibial base plate. 14 patients had a well fixed femoral component and hence were retained while 46 patients had both the components revised. All patients were prospectively assessed prior to surgery, at three months, six months and yearly thereafter. Review comprised clinical and radiological assessment. The mean follow up was 8.4 yrs (7–12 yrs)

Summary of results: The mean pre-operative Hospital for Special Surgery knee score after the first revision improved at a follow up of 8.4yr (7–12yr) giving 39 (65%) excellent, 17 (28.4%) good and four (6.6%) poor results. 13 out of 60 knees needed a further revision. Six of these second revisions which had only the tibial component changed failed very early (mean of 2.1 yr) when compared to the rest (6.8yr), probably due to wear between the abraded retained femoral component and polyethylene insert. The estimated odds ratio (relative risk) of second revision in patients with retained femoral component compared to those with revision of both the components was 4.17 (95% C.I. 1.07 – 15.4).

Conclusion: We recommend exchange of all the components at the time of revision of PCA knee prostheses. Significance: To our knowledge, this is the only study involving such a large number of PCA revisions and looking into the effect of retaining the femoral component compared to changing both the components on the outcome of revision.

Aim: To prospectively determine the functional outcome of revision total knee replacement (TKR).

Method: We carried out a prospective outcome study recruiting 65 consecutive revision total knee replacements carried out by the senior author between 1992 and 1995. The indications for revision were aseptic loosening in 40 cases, instability in 7, infection in 4, and 16 cases for other causes. All patient was assessed preoperatively and at 3 and 12 months postop using the Nottingham Health Profile (NHP) to measure general health status. As part of this ongoing study, followup data is available for 24 patient at 5 years.

Results: There were 65 revisions in 60 patients, 5 being bilateral. There were 37 females and 23 males, with a mean age of 63 years (range 29 to 86 years). The preoperative scores showed that the patient had significant disability related to their failed TKR. Three months postop, there was a significant improvement in the NHP scores for pain and social isolation. At 12 months, the level of pain was again significantly improved over the 3 month score.

At 5 years, the pain score for the revision group deteriorated but remained better than the baseline level. This is in contrast to post primary TKR, where the improvement in pain score was maintained from 3 months onwards.

Conclusion: This study shows a significant improvement in the level of pain following revision knee arthroplasty. However, patients remain significantly disabled afterwards and do not show the very marked improvement in general health seen after primary TKR.

Introduction: The management of the acutely locked knee remains controversial. The incidence of ‘benign’ causes for an acutely locked knee that do not require surgical intervention is perhaps greater than is generally appreciated.

Aim: To study the features of the acutely locked knee, identifying which features are predictive of the cause of the locking.

Patients: Consecutive patients presenting with an acutely locked knee for Orthopaedic consultation were included in the study.

Methods: A prospective cross-sectional study was undertaken to observe the management of acutely locked knees.

Results: To date, forty patients presenting with acutely locked knees have been studied. Thirty-eight underwent examination and arthroscopy under general anaesthesia. 85% of patients were found to have distinct pathology causing a mechanical block to full extension. Eight percent were found to have only degenerative change and two patients unlocked without any surgical intervention. In those patients found to have a mechanical block to extension, consistent features of a definitive injury, joint line tenderness and the presence of an effusion were strongly predictive. We are currently evaluating an algorithm for the pre-operative prediction of remediable mechanical causes of locking.

Discussion: We suggest that patients presenting with acutely locked knees due to a non-mechanical cause can be identified consistently based upon the history and examination alone.