Increasing Rates of Arthroplasty for Psoriatic Arthritis in the United Kingdom Between 1995 and 2010

Combination of C-reactive protein and fibrinogen is useful for diagnosing periprosthetic joint infection in patients with inflammatory diseases

BACKGROUND

The screening of periprosthetic joint infection (PJI) in patients with inflammatory diseases before revision arthroplasty remains uncertain. Serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), plasma fibrinogen (FIB), monocyte/lymphocyte ratio, and neutrophil/lymphocyte ratio (NLR) can help screening PJI, but their values in patients with inflammatory diseases have not been determined.

METHODS

Patients with inflammatory diseases who underwent revision hip or knee arthroplasty at West China Hospital, Sichuan University, from January 2008 to September 2020 were divided into infected and non-infected groups based on the 2013 International Consensus Meeting criteria. Sensitivity and specificity of the tested biomarkers for diagnosing infection were determined based on receiver operating characteristic (ROC) curves, and optimal cutoffs were determined based on the Youden index. The diagnostic ability of these biomarkers was re-assessed after combining them with each other.

RESULTS

A total of 62 patients with inflammatory diseases were studied; of them 30 were infected. The area under the ROC curve was 0.813 for CRP, 0.638 for ESR, 0.795 for FIB, and 0.656 for NLR. The optimal predictive cutoff of CRP was 14.04 mg/L with a sensitivity of 86.2% and a specificity of 68.7%, while FIB had a sensitivity of 72.4% and a specificity of 81.2% with the optimal predictive cutoff of 4.04 g/L. The combinations of CRP with FIB produced a sensitivity of 86.2% and specificity of 78.1%.

CONCLUSION

CRP with a slightly higher predictive cutoff and FIB are useful for screening PJI in patients with inflammatory diseases, and the combination of CRP and FIB may further improve the diagnostic values.

TRIAL REGISTRATION

ChiCTR.org.cn, ChiCTR2000039989.

Trends in orthopaedic surgery for spondyloarthritis: outcomes from a National Hospitalised Patient Registry (MBDS) over a 17-year period (1999-2015).TREND-EspA study

Objective

To assess the incidence of orthopaedic surgery (OS) (including total hip arthroplasty (THA), total knee arthroplasty, upper limb arthroplasty, arthrodesis and spinal surgery) and associated trends in patients with spondyloarthritis (SpA) over a long period (17 years).

Methods

An observational, retrospective, population-based, serial cross-sectional study was conducted. All hospital admissions of patients with SpA reported between 1999 and 2015 were analysed, and a control group was selected and matched by age, sex and year of admission. Incidence rates for OS (and subtypes) were calculated. Generalised linear models were used to analyse trends; unconditional logistic regression models were used to calculate crude and adjusted ORs (aORs) with the aim of evaluating the association between OS and SpA.

Results

The study database contained data on 214 280 hospital admissions (SpA/non-SpA 1:1 ratio). In the SpA cohort, 5 382 admissions (5.02%) had undergone OS compared with 3 533 in the non-SpA cohort (3.29%) (AOR 1.64; 95% CI 1.57 to 1.72). OS rates increased for both cohorts (+4.92% per year vs +8.41%). The trend in OS, THA, arthrodesis and spinal surgery decreased or stabilised in patients under age 60 in the SpA cohort, while the non-SpA cohort remained stable. In the SpA cohort, the mean age was 53.68 years (SD 13.65) in 1999, increasing to 62.76 years (SD 12.74) in 2015. In the non-SpA cohort, the mean age remained stable at around 63 years.

Conclusions

A 9-year difference in the age of patients undergoing OS was observed in patients with SpA. The incidence of OS, THA and arthrodesis decreased in patients under age 60, and the incidence of spinal surgery decreased in patients under age 40. Our findings suggest that these patients are increasingly able to defer surgical interventions.

Spondyloarthritis is associated with higher healthcare utilization and complication rates after primary total knee or total hip arthroplasty

Our objective was to assess healthcare utilization and complication rates after primary total knee/hip arthroplasty (TKA/THA) in people with spondyloarthritis (SpA) compared with people without SpA. We performed multivariable-adjusted logistic regression using the 1998-2014 US National Inpatient Sample (NIS), adjusted for age, race/ethnicity, gender, income, Deyo-Charlson comorbidity index, insurance payer, and the underlying diagnosis. The primary THA cohort consisted of 4,116,484 THAs (1.7% with SpA) and primary TKA cohort of 8,127,282 TKAs (1% with SpA). Compared with people without SpA, people with SpA had higher odds ratio (OR (95% confidence interval (CI)) of the following post-THA and post-TKA, respectively: (1) discharge to care facility, 1.16 (1.12, 1.21) and 1.14 (1.11, 1.18); (2) hospital stay > 3 days, 1.15 (1.11, 1.20) and 1.05 (1.01, 1.10); and (3) transfusion, 1.16 (1.12, 1.21) and 1.10 (1.05, 1.14); but lower odds of (1) mortality, 0.78 (0.64, 0.96) and 0.40 (0.19, 0.84); and (2) hospital charges above the median, 0.49 (0.46, 0.53) and 0.48 (0.45, 0.51). SpA was associated with higher odds of implant infection, 3.02 (2.27, 4.03) post-TKA, not post-THA. In-hospital revision rate did not differ. People with SpA utilize more healthcare services and have more complications post-THA/TKA. Interventions to reduce complications and associated utilization are needed. Key Points • People with spondyloarthritis utilized more healthcare services and had a higher risk of transfusion post-THA/TKA, compared with people without spondyloarthritis. • Spondyloarthritis was associated with lower in-hospital mortality rates after THA/TKA. • Spondyloarthritis was associated with a higher risk of implant infection after TKA, but not THA. • A pre-operative discussion with people with spondyloarthritis of possibly higher implant infection after TKA could lead to a more informed consent.

Incidence and time trends of joint surgery in patients with psoriatic arthritis: a register-based time series and cohort study from Denmark

OBJECTIVE

To investigate time-trends and cumulative incidence of joint surgery among patients with psoriatic arthritis (PsA) compared with the general population.

METHODS

In this nationwide register-based cohort study, The Danish National Patient Registry was used to identify incident PsA patients. The 5-year incidence rates (IR) and incidence rate ratios (IRR) of joint surgery were calculated in four calendar-period defined cohorts. Each patient was matched with ten non-PsA individuals from the general population cohort (GPC). The cumulative incidences of any joint and joint-sacrificing surgery, respectively, were estimated using the Aalen-Johansen method.

RESULTS

From 1996 to 2017, 11 960 PsA patients (mean age 50 years; 57% female) were registered. The IRR of any joint surgery was twice as high for PsA patients compared with GPCs across all calendar periods. Among patients with PsA, 2, 10 and 29% required joint surgery at 5, 10 and 15 years after diagnosis. The risk of surgery in PsA patients diagnosed at 18-40 years was higher (22%) than in GPC 60+ year old (20%) after 15 years of follow-up.

CONCLUSIONS

The use of joint surgery among PsA patients remained around twofold higher from 1996 to 2012 compared with GPC. After 15 years of follow-up, nearly 30% of the PsA patients had received any surgery, and even a person diagnosed with PsA at the age of 18-40 years had a higher risk of surgery than GPCs of 60+ year old. Thus, the high surgical rates represent an unmet need in the current treatment of PsA.