There is sufficient evidence that specialised orthopaedic services, in the form of ‘hub’ or specialist centres, which undertake a high volume of workload in revision arthroplasty generate superior outcomes.

The East Midlands South Orthopaedic Network (EMSSON) was set up in 2015 and is an example of a ‘hub and spoke’ network. The network has recently undergone adaptation in light of the COVID-19 pandemic. There is paucity of data considering the impact of such adaptations in a post-pandemic era and on adherence to advice given.

Two data sets were obtained from the EMSSON data base, pertaining to pre and post pandemic eras respectively. Datasets were analysed and compared for case volumes, proportion of overall arthroplasty volume discussed and adherence to agreed management plans.

Dataset one included 107 cases, of these 99 cases were discussed (54 knees and 45 hips). This equates to 35% of total revision arthroplasty volume recorded in the National Joint Registry (NJR), by units involved in the network. A change of plan was recommended in 45/99 cases (45%), of these 41 (93%) were adhered to. Dataset two included 99 cases, of these 98 were discussed (39 knees and 59 hips). This equates 68% of revision arthroplasty volume performed by the region according to NJR records. A change in plan was recommended in 20 cases (20.5%), all of which were adhered to. One case was referred to the ‘hub’ for surgery.

Following the implementation of recent adaptations, the efficiency of the EMSSON network has significantly improved. A greater volume and proportion of revision arthroplasty cases are now being discussed on a weekly basis. Management plans for which adaptations are suggested have decreased, indicating an educational value of such networking practices. Adherence to agreed plans also showed improvement (p<0.03).

These findings demonstrate a trend towards NHS England's target of 100% of revision arthroplasty cases undergoing MDT discussion. Changes made in light of the Covid-pandemic, are felt to have contributed significantly to the overall performance of regional networking and have been well received by consultants involved.

Introduction

Renal impairment following major surgery is a formidable complication. There is recent evidence suggesting increasing risk of progression to chronic kidney disease and mortality after transient renal impairment. We aimed to evaluate the impact of pre-operative comorbidities on long-term outcomes of renal-function following hip arthroplasty.

Introduction

Titanium and its alloys are attractive biomaterials attributable to their desirable corrosion, mechanical, biocompatibility and osseointegration properties. In particular, β – titanium alloys like the TMZF possess other advantages such as its lower modulus compared to Ti6Al4V alloy. This reduces stress shielding effect in Total Hip Arthroplasty (THA) and the replacement of V in the Ti6Al4V alloy, eliminates in-vivo V-induced toxicity. Unfortunately, implants made of TMZF were later recalled by the FDA due to higher than acceptable revision rates. The purpose of this study was to compare the fretting corrosion characteristics of Ti6Al4V and TMZF titanium alloys. It is hoped the findings will inform better design of β – titanium alloys for future applications in THA.

Introduction: To report the 11-year follow-up of patients of contaminated femoral heads donated at primary total hip replacement from a cohort study published in 2004.

Methods: Of the 440 donors, 266 patients (61%) were still alive at a mean of 11.7 years post primary total hip replacement and 170 patients (64%) agreed to review. The patients had either a positive or negative culture from their donated femoral head at primary total hip replacement. The Oxford hip score, European Quality of Life (EuroQOL) questionnaire, rates of complication and revision surgery were used as outcome measures.

Results: At long-term follow-up, the Oxford hip score was not different between the positive (mean = 36, standard deviation = 12.3) and sterile (mean = 39, standard deviation = 10.9) groups (p = 0.40). The EuroQOL questionnaire was also not different between the positive and sterile groups. There was no statistically significant difference in the rate of complications (p = 0.93) and revision surgery (p = 0.11) of the age-matched patients whose femoral heads had a positive culture compared with those whose femoral heads were sterile.

Discussion: The results of this 11-year follow-up of contaminated donated femoral heads cohort study were similar to those at short-term follow-up. Culture results of donated femoral heads play no significant role in predicting failure of primary total hip replacement in the donor at long-term follow-up.

We report the 15 year follow-up of displaced intra-articular calcaneal fractures from a randomised controlled trial of conservative versus operative treatment. Of the initial study, 46 patients (82%) were still alive and 26 patients (57%) agreed to review.

The clinical outcomes were not different between operative versus conservative treatment. American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scale: p = 0.11; Foot Function Index (FFI): p = 0.66; and calcaneal fracture score: p = 0.41. The radiological outcomes also were not different between both groups. Böhler’s angle: p = 0.07; height of calcaneum: p = 0.57; and grade of osteoarthritis of the subtalar joint: p = 0.54. There was no correlation between Böhler’s angle and the outcome measures in either group.

The results of this 15 year follow-up of displaced intra-articular calcaneal fracture randomised controlled trial demonstrate similar findings to those at one year follow-up.

Introduction: Transmission of infection is always a concern in allograft bone banking and the surgical applications of such bone.

Aim: To review the microbiological results of the femoral head donor program at Perth Bone and Tissue Bank from March 1992 until April 2001.

Methods: There were 4515 femoral head donations. All were cultured by means of a swab and bone chip at time of retrieval, prior to storage at −75 degrees C. Once six month repeat serological testing of donors had been obtained, the heads were processed under sterile conditions. All soft tissues were removed, the bone was milled and washed with 1.5 litres warm saline as pulsed lavage. A microbiological swab was taken prior to packaging the graft ready for irradiation and freezer storage until use.

Results: Five hundred and seventy-nine femoral heads had a positive swab or chip at retrieval, with 31 cases having the same organism on both tests. In 516 cases only one of these tests was positive, with skin organisms being the dominant finding. In 10 cases the swab at the end of processing was positive on culture. Eight of these cases were negative on retrieval testing, and in only one case was the same organism, a coagulase negative staphylococcus, present on the processing swab and retrieval testing.

Conclusions: This work suggested that microbiological culture of femoral head swabs and bone chips at time of retrieval has little effect on the culture at the end of processing. After storage at −75 degrees C, mechanical cleaning and washing, less than 1% of femoral heads were positive prior to irradiation.

Articular cartilage defects of the knee occur commonly in sports injuries and trauma. Increasing evidence suggests that the only technique that enables the regeneration of articular hyaline cartilage in chondral defects is autologous chondrocyte implantation (ACI). Here we have reported our clinical experience of autologous chondrocyte implantation using biodegradable type I/III collagen membrane (CACI). A total of 26 patients (age range from 19 to 60 years, average 37 years) was conducted with CACI. Pre-operative magnetic resonance imaging (MRI) scans were performed on all patients. Post-operative MRI scans were planned for approximately three and 12 months after the surgery to determine the success of integration of implanted chondrocytes.

The results demonstrated that the initial post-operative MRI scans at three months showed the presence of oedematous tissue at the defect sites in 23 patients, contrasting with the fluid filled defects seen preoperatively and with and MRI signal differing from that of the surrounding normal hyaline articular cartilage. MRI scans in nine patients at 12 months after their operations showed maturation of cartilage graft in all patients. Apopototic testing of the chondrocytes using Annexin IV before implantation showed that the viability of the chondrocytes was over 85% where the apopototic rate of chondrocytes was less than 2%. One patient with an apopototic rate of over 10% has a delayed repair in cartilage defects as shown by MRI.

In conclusion, early phase clinical studies showed that autologous chondrocyte implantation remains promising for the treatment of chondral defects with restoration of hyaline cartilage. Longer clinical follow-up of the patients and better assessment of cellular phenotype of chondrocytes before implantation are required.

Introduction: Deep infection remains a major complication of joint arthroplasty. Major randomised controlled trials to determine the most effective antibiotic prophylaxis are difficult to construct and interpret. In a conventional theatre most orthopaedic intraoperative wound contamination arrives by the airborne route.

Aim: To use a unique method to compare antibiotics against these airborne bacteria.

Method: Seven antibiotics were tested; Cephradine, Cefuroxime, Cefotaxime, Flucloxacillin, Amoxycillin, Co-amoxyclav and Imipenem. They were incorporated into blood agar at concentrations equivalent to serum levels. Plates were then inoculated with airborne theatre bacteria using a multiple synchronous collection technique. After incubation, the percentage kills were calculated for each antibiotic.

Results: At concentrations equivalent to serum levels one hour following an intravenous dose all of the antibiotics proved highly effective, with kill rates greater than 95%. Imipenem and Co-amoxiclav significantly outperformed the other antibiotics with kill rates of 99.6% and 99.4% respectively. At trough levels the antibiotics achieved kill rates from 61% to 97.6%.

Discussion: Future randomised controlled trials comparing antibiotics in the setting of an already low infection rate are inappropriate. This technique for comparing antibiotic prophylaxis is quick, inexpensive and repeatable. The superiority of Imipenem is not unexpected, given its broad spectrum against both gram positive and negative, aerobic and anaerobic bacteria. Of more interest is the effectiveness of Co-amoxiclav over the presently favoured Cefuroxime.