Long-term mortality rates and associated risk factors following primary and revision knee arthroplasty

Aims The aim of this study was to determine the long-term mortality rate, and to identify factors associated with this, following primary and revision knee arthroplasty (KA). Methods Data from the Scottish Arthroplasty Project (1998 to 2019) were retrospectively analyzed. Patient mortality data were linked from the National Records of Scotland. Analyses were performed separately for the primary and revised KA cohorts. The standardized mortality ratio (SMR) with 95% confidence intervals (CIs) was calculated for the population at risk. Multivariable Cox proportional hazards were used to identify predictors and estimate relative mortality risks. Results At a median 7.4 years (interquartile range (IQR) 4.0 to 11.6) follow-up, 27.8% of primary (n = 27,474/98,778) and 31.3% of revision (n = 2,611/8,343) KA patients had died. Both primary and revision cohorts had lower mortality rates than the general population (SMR 0.74 (95% CI 0.73 to 0.74); p < 0.001; SMR 0.83 (95% CI 0.80 to 0.86); p < 0.001, respectively), which persisted for 12 and eighteight years after surgery, respectively. Factors associated with increased risk of mortality after primary KA included male sex (hazard ratio (HR) 1.40 (95% CI 1.36 to 1.45)), increasing socioeconomic deprivation (HR 1.43 (95% CI 1.36 to 1.50)), inflammatory polyarthropathy (HR 1.79 (95% CI 1.68 to 1.90)), greater number of comorbidities (HR 1.59 (95% CI 1.51 to 1.68)), and periprosthetic joint infection (PJI) requiring revision (HR 1.92 (95% CI 1.57 to 2.36)) when adjusting for age. Similarly, male sex (HR 1.36 (95% CI 1.24 to 1.49)), increasing socioeconomic deprivation (HR 1.31 (95% CI 1.12 to 1.52)), inflammatory polyarthropathy (HR 1.24 (95% CI 1.12 to 1.37)), greater number of comorbidities (HR 1.64 (95% CI 1.33 to 2.01)), and revision for PJI (HR 1.35 (95% 1.18 to 1.55)) were independently associated with an increased risk of mortality following revision KA when adjusting for age. Conclusion The SMR of patients undergoing primary and revision KA was lower than that of the general population and remained so for several years post-surgery. However, approximately one in four patients undergoing primary and one in three patients undergoing revision KA died within tenten years of surgery. Several patient and surgical factors, including PJI, were associated with the risk of mortality within ten years of primary and revision surgery. Cite this article: Bone Joint J 2022;104-B(1):45–52.

Recovery patterns in patients undergoing revision surgery of the primary knee prosthesis

Purpose Despite good survival rates of revised knee prostheses, little is known about recovery trajectories within the first 12 months after surgery. This retrospective observational study explored recovery trajectories in terms of pain, function and quality of life in patients after revision knee arthroplasty over 12 months. Methods Eighty-eight revision knee arthroplasty patients rated changes in daily physical functioning using the anchor question (0: very much worsened; 7: very much improved). Patient reported outcome measures (PROMs) of pain (range 0–10), function (Oxford Knee Score) and quality of life (EQ-5D-3L) were assessed preoperatively, at 3 and 12 months postoperatively. Four recovery trajectories were identified using the anchor question at 3 and 12 months postoperatively: no improvement, late improvement, early improvement, and prolonged improvement. Repeated measures ANOVA was conducted with recovery trajectories as dependent variable and PROM assessments as independent variables. Results Sixty percent reported improvement in daily physical functioning at 12 months postoperatively. Age and reason for revision differed between groups. Pain, function and EQ-5D-3L differed between groups over time. Late and prolonged improvement groups improved on all PROMs at 12 months. The early improvement group did not report improvement in daily physical functioning at 12 months, while improvements in function and pain during activity were observed. Conclusions Different recovery trajectories seem to exist and mostly match PROMs scores over time. Not all patients may experience beneficial outcome of revision knee arthroplasty. These findings are of importance to provide appropriate information on possible recovery trajectories after revision knee arthroplasty to patients. Level of evidence III

Custom Made Implant in Revision Knee Arthroplasty with AORI 3 Bone Defect: а Case Report

Background. Replacement of extensive bone defects during revision knee arthroplasty (RKA) is a certain problem. The development of additive technologies allows us to produce an individual titanium augment to restore the lost bone tissue. The aim of the study is to show the possibility of replacing extensive tibia defects with an custom made augment during revision knee artroplasty. Case presentation. The patient is 66 years old. At the age of 58, due to secondary knee osteoarthritis in 2 years interval, the patient underwent total knee arthroplasty: left in 2012, right in 2014. Subsequently, several revision interventions were required for early periprosthetic infection of the right knee joint. From 2015 to 2018, due to the infection remission, the function of the right knee joint was satisfactory. In 2018, the patient admitted to our clinic with the periprosthetic infection relapse. Due to the previous treatment, the patient had type 3 bone defect according to the AORI classification. A two-stage revision knee arthroplasty was performed. To compensate the extensive tibial defect, the individual tibial implant was manufactured using additive technologies, and a semiconstrained endoprosthesis was implanted. There was no relapse of infection during the observation. There is deficit of active extension, there are no radiological signs of the implant instability. Conclusion. In our case, we were able to achieve satisfactory results in patient with a complex anamnesis and extensive bone defects. The use of individual implant helped to avoid arthrodesis, preserve the weight-bearing of the lower limb and articulation in the knee joint. The use of implants made using 3D technologies is a promising solution for compensating defects of types 2B and 3 according to the AORI classification.

Possibilities of latent PJI detection in revision knee arthroplasty

Introduction The paper presents a comparative analysis of routine screening methods and the EBJIS 2021 algorithm in detection of latent periprosthetic joint infection in patients admitted for revision knee arthroplasty due to aseptic loosening and after spacer implantation. Materials and methods Group 1 included 49 patients who underwent revision knee arthroplasty due to aseptic loosening, group 2 were 47 patients with PJI after spacer implantation. Results and discussion There were no significant differences between patient groups in terms of age, gender, and preoperative ESR and CRP levels. In 62.2 % of all cases, the aspirate was inappropriate for cytological examination; this fact limited its diagnostic value. The most frequently intraoperatively isolated pathogen in both groups was coagulase-negative staphylococci. However, in 70 % of cases these results were not diagnostically significant, and infection was diagnosed only in 8.2 % of cases in group 1 and 12.8 % in group 2. Moreover, the chances of isolating the pathogen from tissue biopsies were 5.6 times higher than from intraoperative aspirate (OR = 5.6, 95 % CI = 1.2-26.4). In case of negative preoperative aspirate, in almost 25 % of cases, pathogens were isolated from intraoperative tissues, 40.9 % of them were diagnostically significant. The chances of its detection increased 4.7 times in combined increase in ESR and CRP blood level (OR = 4.686, 95 % CI = 0.765-28.700). Using EBJIS 2021 criteria, infection was confirmed in more than 10 % of cases in each group, and the diagnostic significance of the criteria exceeded the significance of using routine screening methods. At a follow-up period of more than 2 years, the effectiveness of treatment was 95.3 %, while signs of infection were detected in 4.7 % of cases, regardless of the group. Conclusion EBJIS 2021 criteria are characterized by high diagnostic sensitivity and specificity and enable to identify periprosthetic joint infection in knee revision cases even in its latent form and to correct treatment tactics in patients without a history of PJI.

Differences in mortality and complication rates following revision knee arthroplasty performed for urgent versus elective indications

Aims To compare rates of serious adverse events in patients undergoing revision knee arthroplasty with consideration of the indication for revision (urgent versus elective indications), and compare these with primary arthroplasty and re-revision arthroplasty. Methods Patients undergoing primary knee arthroplasty were identified in the national Hospital Episode Statistics (HES) between 1 April 1997 to 31 March 2017. Subsequent revision and re-revision arthroplasty procedures in the same patients and same knee were identified. The primary outcome was 90-day mortality and a logistic regression model was used to investigate factors associated with 90-day mortality and secondary adverse outcomes, including infection (undergoing surgery), pulmonary embolism, myocardial infarction, and stroke. Urgent indications for revision arthroplasty were defined as infection or fracture, and all other indications (e.g. loosening, instability, wear) were included in the elective indications cohort. Results A total of 939,021 primary knee arthroplasty procedures were included (939,021 patients), of which 40,854 underwent subsequent revision arthroplasty, and 9,100 underwent re-revision arthroplasty. Revision surgery for elective indications was associated with a 90-day rate of mortality of 0.44% (135/30,826; 95% confidence interval (CI) 0.37 to 0.52) which was comparable to primary knee arthroplasty (0.46%; 4,292/939,021; 95% CI 0.44 to 0.47). Revision arthroplasty for infection was associated with a much higher mortality of 2.04% (184/9037; 95% CI 1.75 to 2.35; odds ratio (OR) 3.54; 95% CI 2.81 to 4.46), as was revision for periprosthetic fracture at 5.25% (52/991; 95% CI 3.94 to 6.82; OR 6.23; 95% CI 4.39 to 8.85). Higher rates of pulmonary embolism, myocardial infarction, and stroke were also observed in the infection and fracture cohort. Conclusion Patients undergoing revision arthroplasty for urgent indications (infection or fracture) are at higher risk of mortality and serious adverse events in comparison to primary knee arthroplasty and revision arthroplasty for elective indications. These findings will be important for patient consent and shared decision-making and should inform service design for this patient cohort. Cite this article: Bone Joint J 2021;103-B(10):1578–1585.