Introduction

Knee arthroscopy can be used for ligamentous repair, reconstruction and to reduce burden of infection. Understanding and feeling confident with knee arthroscopy is therefore a highly important skillset for the orthopaedic surgeon. However, with limited training or experience, furthered by reduced practical education due to COVID-19, this skill can be under-developed amongst trainee surgeons.

Abstract

Purpose

Infections in orthopaedic surgery are costly, debilitating complications. The search for new treatments and prevention strategies has led to the use of antibiotic-filled calcium sulfate (CaS) as a bone void filler that is both safe and effective. The purpose of this study was to examine the available data on the efficacy of this technology.

Summary

A meta-analysis was performed to compare rate of SSI after application of chlorhexidine vs. iodine in total joint arthroplasty. Chlorhexidine had significantly lower odds of SSI.

Patients who have multiple sclerosis (MS) may be at increased risk of developing complications after total hip arthroplasty (THA). The purpose of this study was to compare: 1) implant survivorship; 2) functional outcomes; 3) complication rates; and 4) radiographic findings after THA between MS patients and a matched cohort.

A single institutional database was reviewed for patients who had a diagnosis of MS and underwent a THA. Thirty-four patients (41 hips) were matched to a 2:1 cohort who did not have MS using based on age, sex, body mass index (BMI), and Charlson/Deyo scores. This resulted in a matching cohort of 80 patients (82 hips). The available medical records were reviewed. Functional outcomes and complications were assessed. Postoperative radiographs were evaluated.

The matching cohort had higher all-cause survivorship at 4-years postoperatively (99 vs. 93%). There were 3 revisions in the MS cohort and 0 revisions in the matching cohort. The MS cohort had lower mHHS scores (66 vs.74 points, p<0.001), lower HOOS JR scores (79 vs. 88 points, p<0.01), required more physical therapy (5 vs. 3 weeks, p<0.01), and took longer to return to their baseline functional level (7 vs. 5 weeks, p<0.05). MS patients had higher rate of complications (6 vs. 1, p<0.05). Excluding revision cases, there was no additional radiographic evidence of progressive radiolucency, loosening, or subsidence.

We found that MS patients had lower implant survivorship, lower functional outcome scores, and increased complication rates. These findings may help orthopaedists to have a better knowledge of how MS patients do after THA.

Introduction

Stiffness after total knee arthroplasty is a common occurrence. Despite its prevalence, little is known as to which patients are at risk for poor range of motion after total knee arthroplasty. The purpose of this study was to determine the risk factors for manipulation under anesthesia (MUA) after total knee arthroplasty (TKA).

Purpose

The aim of this study was to compare the short-term and mid-term outcome of lateral UKRs using a single prosthesis, the AMC Uniglide knee implant.

Introduction

Kneeling ability is better in unicompartmental than total knee arthroplasty. There is also an impression that mobile bearing knees achieve better functional outcome than their fixed bearing cousins in unicompartmental and to a lesser extent total joint arthroplasty. In the UK, the market leading unicompartmental replacement is mobile bearing.

Introduction

Trochlear dysplasia (TD) is still poorly recognised, generally considered uncommon and to present purely as persistent patella dislocation.

Between 1989 and 1992 102 knees adjudged suitable for Unicompartmental replacement (UKR) were randomised to receive either a St Georg Sled UKR or a Kinematic modular total knee replacement (TKR). The early results demonstrated that the UKR group had less complications, and more rapid rehabilitation. At 5 years there were equal failures but the UKR group had more excellent results and a greater range of movement.

Despite this doubt persisted about whether these advantages would be maintained these cases have been followed regularly by a research nurse at 8, 10, 12 years. We now report the final outcome at 15 years. 43 patients (45 knees) have died with all their knees intact. Throughout the review period the Bristol Knee Scores (BKS) of the UKR group have been better and at 15 years 77% and 53% of the surviving UKRs and TKRs achieve an excellent score. 6 TKRs and 4 UKRs have failed during the 15 years of the review.

Background

Unicompartmental knee replacements (UKR) converted to total knee replacements (TKR) have often been viewed with scepticism because of the perceived difficulty of the revision and because revision procedures generally do less well than primaries.

Introduction

The Bristol Knee Group has prospectively followed the results of over 500 isolated patellofemoral arthroplasties. Initial experience with the Lubinus prosthesis was disappointing. The main causes of failure were mal-tracking and instability leading to excessive polythene button wear and disease progression in the tibio femoral joint.

This experience resulted in the design of a new prosthesis to correct the tracking problems and improve the wear. We have now performed over 425 Avon arthroplasties with a maximum follow-up of 9 years.

Background: Although many knee surgeons routinely perform unicompartmental replacement (UKR) for medial compartment arthrosis there is still reluctance to perform lateral UKR’s as they are generally thought to be less satisfactory. The purpose of the present study was to prospectively compare the outcome of lateral UKR’s with medial UKR’s using the AMC Uniglide knee implant.

Methods: Between 2002 and 2005, 29 lateral fixed bearing AMC Uniglide UKR’s were performed at our unit. American Knee Society (AKS), Oxford and WOMAC scores were recorded pre-operatively and at two years post-op and compared with the results of 50 medial mobile bearing and 50 medial fixed bearing AMC Uni-glide UKR’s performed during the same time period. Data was acquired by a research nurse and recorded prospectively on the Bristol Knee Database. The mean ages of the patients were: 63 years in the lateral UKR group was, 62 years in the medial mobile bearing group and 69 in the medial fixed bearing group. The groups were equally sex matched with a predominate number of females in each group. There was no difference between the pre-operative scores for the 3 groups.

Results: At one-year review, the 3 groups had similar mean scores: (table removed)

Conclusions: This study suggests that at two years the quality of outcome of Lateral UKR’s is at least equivalent to both fixed and mobile bearing medial compartment UKR’s. However, continued long-term survivorship studies are needed to assess failure rates of Lateral fixed bearing UKR’s and particularly to evaluate progression of arthritis in the medial compartment. The procedure should form part of the knee surgeons’ armamentarium, but the differences in the operative techniques for lateral and medial UKR must be appreciated.

Although good long term results for fixed bearing uni-compartmental knee replacements (UKRs) have been reported mobile bearings predominate in some parts of the world. Three prospective studies have been undertaken comparing the short and medium term outcomes of fixed and mobile UKRs.

A 5 year comparative cohort study of 47 Oxford mobile bearing and 57 St Georg Sled fixed bearing UKRs.

In all groups the preoperative sex mix, average age and knee scores were extremely similar.

All patients were assessed both pre and postoperatively by a research nurse and radiographs were taken; the results were entered on the Bristol Knee database.

Results:

Multiple problems were encountered, perhaps because of the introduction of MIS, but at 5 years 11 Oxford and 4 Sleds had failed. The major problem with the mobile bearing implant was instability though tibial fractures were also seen. Both groups had three cases of arthritic progression and loose cement was seen twice in the fixed bearing group.

– Amongst the remaining patients the median scores for the Sled were better. Bristol Knee Score (Max 100) 95:90; Oxford (Max 48) 39:37; and reduced WOMAC (Best score 12) 18:24.

Conclusion. Although theoretically mobile bearings will give greater longevity there is frequently a short term price to pay particularly when the procedures are performed by inexperienced surgeons and trainees. Since the wear properties of polyethylene have improved in recent years these studies suggest that a fixed bearing option can be used more safely in many patients.

Introduction: The Bristol Knee group has performed over 600 patellofemoral arthroplasties in the last 18 years. Experience with the Lubinus prosthesis led to the development of the Avon Prosthesis. In the last 11 years we have prospectively recorded the results of over 470 consecutive Avon arthroplasties. The main cause of the 9.5% failure is arthritic disease progression in the tibiofemoral compartments.

Patients and Method: Over the last 11 years we have identified 21 patients from our own series and from tertiary referrals that have persistent pain, which was mainly due to technical error rather than arthritic disease progression. The causes can be classified into three main reasons: First, an incorrect anterior cut in the saggital plane which was cut in either too much flexion or extension. Second, the anterior cut had inadequate external rotation, which should be 3–6 degrees to lateralise the groove and facilitate correct tracking. Third, the prosthesis was oversized in several cases leading to retinacular impingement.

Results: The overall results followed up to 10 years showed excellent and consistent improvement in both pain and function as judged by the WOMAC 12 scale. Of those patients with persistent pain, seven had the femoral component revised to either resize the prosthesis or revise the alignment of the anterior resection and correctly inset the prosthesis, with good results. Ten cases were revised to a total knee replacement. In the remaining cases, two had an Insall realignment, one a patella distalisation, and in one no treatment was required. As a permanent solution new instruments were designed to reduce the incision size and increase the accuracy of the saggial alignment and to create an exact amount of external rotation.

Conclusion: The lessons from 11 years experience with the Avon arthroplasty has led to the development of improved instrumentation which should reduce the failures.

Objectives: This study aims to assess the psychological profile of patients prior to total knee replacement, medial unicompartmental knee replacement and patellofemoral joint replacement and determine its effect on outcome.

Methods: 113 patients were identified (41 TKR, 37 UKR and 35 PFJR). All patients had mental health assessed preoperatively using SF-12. From the 12 questions a mental and a physical summary score can be calculated (MCS and PCS). The reduced WOMAC score was used pre-operatively to assess knee function and symptoms and then recorded at 8 and 24 months post-operation to assess outcome.

Results: 54% of the patients had pre-operative psychological distress. There was no statistically significant difference demonstrated between them mean MCS scores between the three operation groups. Pre-operative MCS had a significant effect such that increasing psychological distress lead to a worse twenty-four month outcome (p = 0.016). The effect of MCS is most marked in postoperative pain levels (p = 0.008) compared to function (p = 0.016). The mean 24-month rWOMAC in the severely distressed group (MCS< 40) was 28.4 compared to 17.4 in the psychologically well group (MCS> 60).

Conclusions: Pre-operative mental function prior to knee arthroplasty may provide useful information to guide patients as to their expected outcome in the consent process. Those patients with a very high mental component may be counseled to that although their distress is likely to improve with surgery, their eventual outcome may be worse. The effect of MCS may however only be clinically relevant in those patients with severe mental symptoms.

Purpose of Study: Fixed bearing unicompartmental knee replacement (UKR) has become popular since several series have now shown good 10 year survivorship and excellent function. However little is known about survival during the second decade.

Method: From the Bristol database of over 4000 knee replacements 203 St. Georg Sled UKR’s which had already survived 10 years were identified. The mean age at surgery was 67 years (48–85), with 64% being female. This cohort has been further reviewed at an average of 14.8 years (10–30) from surgery to determine survivorship and function.

Results: Survivorship during the second decade was 87.5%. 58 patients (69 knees) had died with implant in situ and only 2 after revision. A further 15 UKR’s have been revised at an average of 13 years post op; 7 for progression of disease in the opposite compartment, 4 for tibial loosening, 3 for polyethylene wear, 2 for femoral component fracture and 2 for infection.

99 knees were followed for 15 years, 21 knees for 20 years and four for 25 or more years. The average Bristol knee score of the surviving knees fell from 86 to 79 during the second decade, largely as a result of aging.

A previous study of the St Georg. Fixed bearing UKR showed an 89% 10 year survivorship and this is now extended to 82% at 15 years and 76.5% at 20 years.

Conclusion: Satisfactory survival of fixed bearing UKR can be achieved in the second decade suggesting that the indications for mobile bearings require careful definition since there is a higher incidence of complications in many people’s hands.

Since 1996 over 400 isolated patellofemoral replacements using the Avon prosthesis have been undertaken in Bristol. As a result of the usually gratifying outcomes seen in patients over 55 years old, the indications for this surgery were soon extended to include the many younger patients who have severely disabling patellofemoral disease. We present results from a prospective cohort study of patients under 55 years of age at the time of surgery.

110 knees in 86 patients (median age 47 years, range 24–54) have been treated with Avon patellofemoral replacement (88 in females and 22 in males). Diagnoses included lateral facet OA (59 knees), patella dislocation (25 knees), trochlear dysplasia (41 knees) and post patellectomy instability (7 knees). 79 knees had undergone previous surgery. 17 knees required additional intra-operative procedures including 11 lateral releases and 2 patella realignments. All patients were assessed pre-operatively and at regular intervals using the Oxford, Bristol and WOMAC scores.

All knees were scored preoperative and only one knee has been lost to follow-up due to the patient’s death, which was unrelated to surgery. Post-operative Oxford knee scores have been obtained for 106 knees with follow-up between 8 months and 8 years (mean follow-up 24 months). The mean Oxford score improved from 18 preoperatively to 31 at latest review. Bristol and WOMAC scores showed similar improvements. 16 knees required post-operative additional procedures including 6 lateral releases, 3 patella realignments and 11 revisions. Of the revisions 5 were for progression of tibiofemoral OA but none of these were knees with trochlear dysplasia. Equally good mean scores were seen when comparing patients with the 3 main underlying pathologies (trochlear dysplasia, patellar dislocation and lateral facet OA). At least 37% of the patients studied had pre-existing trochlear dysplasia and the majority of these patients report onset of symptoms, often patellar dislocation, in the first three decades of life. More than 90% of patients were overweight or obese according to their BMI at the time of surgery.

Many of this type of patient, with disabling symptoms, wish to “live now”. The short-term improvements are frequently dramatic. As yet there is no suggestion of prosthetic failure. Revision presents little difficulty since minimal bone is resected in the primary proceedure. Radiological deterioration of the tibio femoral joint is seen in some cases of primary OA but not with trochlear dysplasia.

Background: In the UK 80% unicompartmental knee replacements(UKRs) and 10% of total knee replacements(TKRs) use mobile bearings. It is suggested that mobile bearings are more physiological and wear less, however it is still unclear whether patients tolerate mobile bearing knee replacements as well.

Patients and methods: We report four prospective studies,. Two compared fixed with mobile bearings in TKR and two in UKR. The prostheses involved were fixed and mobile variants of the Rotaglide (TKR), Kinemax (TKR) and Uniglide (UKR). In addition the Oxford and St. George Sled UKRs were compared. All except the Uniglide study were randomized prospective trials (RCTs)

611 patients were involved with a mean age of 68 years. Residual pain following surgery was assessed with either the Oxford Knee Score (OKS) or the WOMAC score. The patients were followed up at one and two years postoperatively by a Research nurse and the findings recorded prospectively on the Bristol Knee database.

Results:

Conclusion: Our data suggests that the fixed bearing knee replacements result in less residual pain than their mobile bearing counterparts, at least in the first two years following surgery.

Purpose: To review long-term outcome following knee arthrodesis, and compare this with patient outcome following revision knee arthroplasty.

Methods: Case notes and radiographs of patients who underwent arthrodesis using the Mayday nail were reviewed retrospectively for evidence of clinical and radiological union. Patients also completed an SF12 health survey and Oxford knee score in the form of postal questionnaires. Each patient was matched with patients who had undergone revision knee arthoplasty and the outcomes were compared.

Results: 19 patients were reviewed who underwent knee arthrodesis using a Mayday nail in two centres between 1993 and 2004. 18 cases had united clinically and radiologically with one case lost to follow-up. Mean SF12 scores of patients following knee arthrodesis indicated severe physical (28.8) but only mild mental (43.3) disabilities. The mean Oxford knee score in this group was 41.0. These results were comparable with matched patients following revision knee arthroplasty who scores 27.2 (physical) and 41.1 (mental) on the SF12, and a mean of 38.8 on the Oxford knee score.

Conclusion: Outcome scores following knee arthrodesis were similar to those following revision knee arthroplasty making it an option worth considering in selected patients requiring revision surgery.

Discussion: The Mayday nail provides a method of knee arthrodesis with a high union rate and an acceptable complication rate. Outcome scores following arthrod-esis were not dissimilar to those following revision total knee replacement. These results suggest that knee arthrodesis may be considered as an acceptable alternative to complex knee revision surgery.