2019 John Insall Award: Fructosamine is a better glycaemic marker compared with glycated haemoglobin (HbA1C) in predicting adverse outcomes following total knee arthroplasty: a prospective multicentre study.

AIMS: The best marker for assessing glycaemic control prior to total knee arthroplasty (TKA) remains unknown. The purpose of this study was to assess the utility of fructosamine compared with glycated haemoglobin (HbA1c) in predicting early complications following TKA, and to determine the threshold above which the risk of complications increased markedly. PATIENTS AND METHODS: This prospective multi-institutional study evaluated primary TKA patients from four academic institutions. Patients (both diabetics and non-diabetics) were assessed using fructosamine and HbA1c levels within 30 days of surgery. Complications were assessed for 12 weeks from surgery and included prosthetic joint infection (PJI), wound complication, re-admission, re-operation, and death. The Youden's index was used to determine the cut-off for fructosamine and HbA1c associated with complications. Two additional cut-offs for HbA1c were examined: 7% and 7.5% and compared with fructosamine as a predictor for complications. RESULTS: Overall, 1119 patients (441 men, 678 women) were included in the study. Fructosamine level of 293 µmol/l was identified as the optimal cut-off associated with complications. Patients with high fructosamine (> 293 µmol/l) were 11.2 times more likely to develop PJI compared with patients with low fructosamine (p = 0.001). Re-admission and re-operation rates were 4.2 and 4.5 times higher in patients with fructosamine above the threshold (p = 0.005 and p = 0.019, respectively). One patient (1.7%) from the elevated fructosamine group died compared with one patient (0.1%) in the normal fructosamine group (p = 0.10). These complications remained statistically significant in multiple regression analysis. Unlike fructosamine, all three cut-offs for HbA1c failed to show a significant association with complications. CONCLUSION: Fructosamine is a valid and an excellent predictor of complications following TKA. It better reflects the glycaemic control, has greater predictive power for adverse events, and responds quicker to treatment compared with HbA1c. These findings support the screening of all patients undergoing TKA using fructosamine and in those with a level above 293 µmol/l, the risk of surgery should be carefully weighed against its benefit. Cite this article: Bone Joint J 2019;101-B(7 Supple C):3-9.

Increased postoperative glucose variability is associated with adverse outcomes following orthopaedic surgery.

Aims: The aim of this study was to examine the association between postoperative glycaemic variability and adverse outcomes following orthopaedic surgery. Patients and Methods: This retrospective study analyzed data on 12 978 patients (1361 with two operations) who underwent orthopaedic surgery at a single institution between 2001 and 2017. Patients with a minimum of either two postoperative measurements of blood glucose levels per day, or more than three measurements overall, were included in the study. Glycaemic variability was assessed using a coefficient of variation (CV). The length of stay (LOS), in-hospital complications, and 90-day readmission and mortality rates were examined. Data were analyzed with linear and generalized linear mixed models for linear and binary outcomes, adjusting for various covariates. Results: The cohort included 14 339 admissions, of which 3302 (23.0%) involved diabetic patients. Patients with CV values in the upper tertile were twice as likely to have an in-hospital complication compared with patients in the lowest tertile (19.4% versus 9.0%, p < 0.001), and almost five times more likely to die compared with those in the lowest tertile (2.8% versus 0.6%, p < 0.001). Results of the adjusted analyses indicated that the mean LOS was 1.28 days longer in the highest versus the lowest CV tertile (p < 0.001), and the odds of an in-hospital complication and 90-day mortality in the highest CV tertile were respectively 1.91 (p < 0.001) and 2.10 (p = 0.001) times larger than the odds of these events in the lowest CV tertile. These associations were significant even for non-diabetic patients. After adjusting for hypoglycaemia, the relationships remained significant, except that the CV tertile no longer predicted mortality in diabetics. Conclusion: These results indicate that higher glycaemic variability is associated with longer LOS and in-hospital complications. Glycaemic variability also predicted death, although that primarily held for non-diabetic patients in the highest CV tertile following orthopaedic surgery. Prospective studies should examine whether ensuring low postoperative glycaemic variability may reduce complication rates and mortality. Cite this article: Bone Joint J 2018;100-B:1125-32.

Can next generation sequencing play a role in detecting pathogens in synovial fluid?

AIMS: The diagnosis of periprosthetic joint infection can be difficult due to the high rate of culture-negative infections. The aim of this study was to assess the use of next-generation sequencing for detecting organisms in synovial fluid. MATERIALS AND METHODS: In this prospective, single-blinded study, 86 anonymized samples of synovial fluid were obtained from patients undergoing aspiration of the hip or knee as part of the investigation of a periprosthetic infection. A panel of synovial fluid tests, including levels of C-reactive protein, human neutrophil elastase, total neutrophil count, alpha-defensin, and culture were performed prior to next-generation sequencing. RESULTS: Of these 86 samples, 30 were alpha-defensin-positive and culture-positive (Group I), 24 were alpha-defensin-positive and culture-negative (Group II) and 32 were alpha-defensin-negative and culture-negative (Group III). Next-generation sequencing was concordant with 25 results for Group I. In four of these, it detected antibiotic resistant bacteria whereas culture did not. In another four samples with relatively low levels of inflammatory biomarkers, culture was positive but next-generation sequencing was negative. A total of ten samples had a positive next-generation sequencing result and a negative culture. In five of these, alpha-defensin was positive and the levels of inflammatory markers were high. In the other five, alpha-defensin was negative and the levels of inflammatory markers were low. While next-generation sequencing detected several organisms in each sample, in most samples with a higher probability of infection, there was a predominant organism present, while in those presumed not to be infected, many organisms were identified with no predominant organism. CONCLUSION: Pathogens causing periprosthetic infection in both culture-positive and culture-negative samples of synovial fluid could be identified by next-generation sequencing. Cite this article: Bone Joint J 2018;100-B:127-33.

A long-term follow-up study of the clinical and radiographic outcome of distal trochanteric transfer in Legg-Calvé-Perthes' disease following varus derotational osteotomy.

AIMS: To assess the long-term effect of distal trochanteric transfer (DTT) on the clinical and radiographic outcomes of patients with Legg-Calvé-Perthes' disease (LCPD) following a varus derotational osteotomy (VDRO). PATIENTS AND METHODS: For this single centre cross-sectional retrospective study we analysed the data of 22 patients (24 hips) with LCPD who had greater trochanteric overgrowth (GTO), following a VDRO performed in our institution between 1959 and 1983. GTO was defined as an articular trochanteric distance (ATD) of < 5 mm. We compared the radiographic and clinical outcomes of patients who underwent DTT for GTO (ten patients, ten hips) with those who did not (12 patients, 14 hips). Age at presentation was 6.9 years (4 to 10) and 8.0 years (3.2 to 12) respectively. Symptoms associated with the hip and general quality of life were assessed using the Harris hip score (HHS) and the Short Form (SF)-36 questionnaires. RESULTS: At long-term follow-up of the DTT group, the ATD was 21.7 mm (standard deviation (sd) 9.8) and the centro-trochanteric distance (CTD) was 13.8 mm (sd 8.3). In the control group the ATD was -0.6 mm (sd 7.8) and the CTD was 32.5 mm (sd 10.2). These differences were statistically significant (p < 0.001). The mean HHS and SF-36 scores were 68.4 (sd 25.0) and 62.0 (sd 27.7) for the DTT group and 73.2 (sd 24.2) and 73.3 (sd 21.5) for the control group, respectively. There was no statistically significant difference in the HHS (p = 0.63) or SF-36 score (p = 0.25). There were four patients who had undergone hip arthroplasty in the DTT group (40%) and one patient (7.1%) in the control group (p = 0.07). The mean age at the time of arthroplasty was 45.3 years (42.1 to 56.5) and 43.6 years respectively. Six patients in the DTT group suffered from moderate to severe osteoarthritis (Tönnis grade 2 or 3) compared with eight patients in the control group (60% versus 57.1%, p = 0.61). CONCLUSION: Although DTT improved the radiographic results in the long-term follow-up of patients with GTO following VDRO, there was no clinical benefit seen in the HHS, SF-36 or incidence of osteoarthritis compared with patients who had not undergone DTT. Cite this article: Bone Joint J 2017;99-B:987-92.

Prevention of periprosthetic joint infection: new guidelines.

The World Health Organization (WHO) and the Centre for Disease Control and Prevention (CDC) recently published guidelines for the prevention of surgical site infection. The WHO guidelines, if implemented worldwide, could have an immense impact on our practices and those of the CDC have implications for healthcare policy in the United States. Our aim was to review the strategies for prevention of periprosthetic joint infection in light of these and other recent guidelines. Cite this article: Bone Joint J 2017;99-B(4 Supple B):3-10.