Applying models of care for total hip and knee arthroplasty: External validation of a published predictive model to identify extended stay risk prior to lower-limb arthroplasty

OBJECTIVE

This study aimed to externally validate a reported model for identifying patients requiring extended stay following lower limb arthroplasty in a new setting.

DESIGN

External validation of a previously reported prognostic model, using retrospective data.

SETTING

Medium-sized hospital orthopaedic department, Australia.

PARTICIPANTS

Electronic medical records were accessed for data collection between Sep-2019 and Feb-2020 and retrospective data extracted from 200 randomly selected total hip or knee arthroplasty patients.

INTERVENTION

Participants received total hip or knee replacement between 2-Feb-16 and 4-Apr-19. This study was a non-interventional retrospective study.

MAIN MEASURES

Model validation was assessed with discrimination, calibration on both original and adjusted forms of the candidate model. Decision curve analysis was conducted on the outputs of the adjusted model to determine net benefit at a predetermined decision threshold (0.5).

RESULTS

The original model performed poorly, grossly overestimating length of stay with mean calibration of -3.6 (95% confidence interval -3.9 to -3.2) and calibration slope of 0.52. Performance improved following adjustment of the model intercept and model coefficients (mean calibration 0.48, 95% confidence interval 0.16 to 0.80 and slope of 1.0), but remained poorly calibrated at low and medium risk threshold and net benefit was modest (three additional patients per hundred identified as at-risk) at the a-priori risk threshold.

CONCLUSIONS

External validation demonstrated poor performance when applied to a new patient population and would provide limited benefit for our institution. Implementation of predictive models for arthroplasty should include practical assessment of discrimination, calibration and net benefit at a clinically acceptable threshold.

[Clinical comparative study on resection and non-resection of the fifth metatarsal to rheumatoid forefoot deformity]

OBJECTIVE

To explore clinical effect of the fifth metatarsal head excision and non-excision in rheumatoid arthritis (RA) forefoot deformity reconstruction.

METHODS

Retrospective analysis was performed on 50 patients (76 feet) with moderate to severe forefoot deformity caused by RA treated from May 2015 to January 2019. According to degeneration of the fifth metatarsophalangeal joint,the fifth metatarsal head was retained or excised by wind-like forefoot reconstruction,and divided into the fifth metatarsal head preservation group (preservation group) and the fifth metatarsal head resection group (resection group). Twenty-four female patients in preservation group,aged from 47 to 81 years old with an average of (60.37±8.60) years old;the course of disease ranged from 13 to 22 years with an average of (19.00±3.06) years;body mass index (BMI) ranged from 21 to 28 kg·m-2 with an average of (23.53±2.47) kg·m-2;six patients (6 feet) with moderate hallux valgus deformity and 18 patients (30 feet) with severe hallux valgus deformity;treated with the first metatarsophalangeal joint fusion combined with the second th the fourth metatarsophalangeal joint arthroplasty and the fifth metatarsophalangeal joint cleanup. Twenty-six female patients in resection group were female,aged from 30 to 80 years old with an average of (58.53±13.70) years old;the course of disease ranged from 8 to 25 years with an average of (17.94±3.92) years;BMI raged from 20 to 28 kg·m-2 with an average of (24.60±2.03) kg·m-2;4 patients (4 feet) with moderate bunion valgus deformity and 22 patients (36 feet) with severe bunion valgus deformity;treated by the first metatarsophalangeal joint fusion combined with the second th the fifth metatarsophalangeal joint resection of the metatarsophalangeal head. Operation time and postoperative complications between two groups were observed,hallux valgus angle (HVA),intermetatarsal angles between the first and the second metatarsals (IMAFS),intermetatarsal angles between the first and fifth metatarsals (IMAFF),Japanese Society for Surgery of Foot (JSSF) score before surgery and at the latest follow-up were compared.

RESULTS

Fifty patients were followed-up from 14 to 46(25.30±8.83) months in resection group and 12 to 48 with an average of (24.30±11.12) months in preservation group,while no significant difference between two groups (P>0.05). There were no significant difference in operation time and postoperative complications between two groups (P>0.05). JSSF scores,HVA,IMAFS and IMAFF in fesection group were improved from (45.09±3.35) points,(38.90±13.67) °,(12.88±1.72) °,(32.50±2.99) ° before operation to (81.60±3.27) points,(15.40±0.90),(9.06±2.27) °,(22.20±1.98) ° at the latest follow-up (P<0.05);preservation group were improved from (47.09±3.96) points,(43.30±12.65) °,(13.99±3.13) °,(33.20±6.14) ° to (83.10±3.66) points,(15.20±1.54) °,(8.99±1.02) °,(24.70±1.88) °,respectively. There were no significant difference in JSSF score,HVA,IMAFS and IMAFF between two groups before operation and the latest follow-up (P>0.05). At the latest follow-up,there were statistically significant differences in pain and deformity in JSSF scores between two groups (P<0.05).

CONCLUSION

Both rheumatoid anterior foot reconstruction and anterior foot reconstruction fifth metatarsophalangeal joint debridement showed significant improvement in clinical efficacy and imaging results. Compared with rheumatoid prefoot reconstruction,the fifth metatarsophalangeal joint reconstruction for the treatment of moderate and severe deformity of rheumatoid prefoot showed better improvement in pain,but worse improvement in deformity. For the moderate to severe deformity of the forefoot caused by rheumatoid disease,patients with mild to moderate degenerative deformity of the articular surface of the fifth metatarsal phalanges may be considered for use.

Effect of Taiwan's Diabetes Shared Care Program on the risk of periprosthetic joint infection after total joint arthroplasty in patients with type 2 diabetes mellitus: an eight-year population-based study

BACKGROUND

Periprosthetic joint infection (PJI) is a significant post-arthroplasty complication for diabetic patients, with uncontrolled diabetes identified as a PJI risk factor. Taiwan's Diabetes Shared Care Program (DSCP) was established for holistic diabetes care.

AIM

To evaluate the DSCP's impact on PJI incidence and patients' medical costs.

METHODS

Data were analysed from Taiwan's National Health Insurance Research Database from 2010 to 2020, focusing on type 2 diabetes mellitus (DM) patients who had undergone arthroplasty. The study group involved DSCP participants, while a comparison group comprised non-participants with matched propensity scores for age, sex, and comorbidities. The primary outcome was the PJI incidence difference between the groups; the secondary outcome was the medical expense difference.

FINDINGS

The study group consisted of 11,908 type 2 DM patients who had arthroplasty and joined the DSCP; PJI occurred in 128 patients. Among non-participants, 184 patients had PJI. The PJI incidence difference between the groups was statistically significant (1.07% vs 1.55%). The study group's medical costs were notably lower, regardless of PJI incidence. Multivariate regression showed higher PJI risk in patients in comparison group, aged >70 years, male, or who had obesity, anaemia.

CONCLUSION

The study indicates that DSCP involvement reduces PJI risks and decreases annual medical costs for diabetic patients after arthroplasty. Consequently, the DSCP is a recommendable option for such patients who are preparing for total joint arthroplasty.

The impact of COVID-19 on hip and knee arthroplasty surgical volume in China

PURPOSE

The reduction of hip and knee arthroplasty surgical volume has been reported in many countries during the COVID-19 pandemic. In China, there is no national joint registry system and the impact of COVID-19 towards surgical volume remains unclear. The aim of this study was to investigate the hip and knee arthroplasty surgical volume in China during the pandemic and evaluate its change trends.

METHODS

Annual sale numbers of prostheses used in total knee arthroplasty (TKA), total hip arthroplasty (THA), and femoral head replacement (FHR) from 2011 to 2021 was collected from providers registered in National Medical Products Administration (NMPA). Annual surgical volume of TKA, THA, FHR, unicompartmental knee arthroplasty (UKA), and revision of hip/knee arthroplasty (RJA) was collected from member hospitals of Beijing Joint Society (BJS). We used linear regression to estimate the loss of surgical volume. Annual surgical volume obtained from Britain and Australian joint registries were used to make comparison.

RESULTS

In China, the surgical volume of THA/FHR, TKA, and UKA in 2020 all decreased compared to the predicted value, with a reduction of 82,525 cases (13.46%), 165,178 cases (33.50%), and 151 cases (0.65%), respectively. All the three procedures showed significant recovery in 2021. The surgical volumes of THA/FHR and UKA were 68,813 and 9402 cases higher than predicted levels, respectively, while TKA volume remained slightly below the predicted level. The regional statistics in Beijing showed similar change mode. In 2020, the surgical volume of THA/FHR, TKA, FHR, and UKA all decreased compared to the predicted value, with a reduction of 5031 cases (43.37%), 5290 cases (40.69%), 620 cases (29.18%), and 925 cases (39.11%), respectively. In 2021, with the exception of FHR, the number of these procedures increased compared to 2020, but remained below the predicted value. Compared with the data from Britain and Australia, China experienced less reduction and faster recovery in the proportions of elderly people (> 65 years old) who undergo hip and knee arthroplasty during the COVID-19 pandemic.

CONCLUSION

During the COVID-19 pandemic, although hip and knee arthroplasty surgical volume in China showed a similar "restoration-recovery" change pattern with other countries, China took fewer losses in this field.

A Retrospective Analysis Investigating Whether Case Volume Experience of the Anesthesiologist Correlates with Intraoperative Efficiency for Joint Arthroplasty

The objective of this retrospective study was to determine if there was an association between anesthesiology experience (e.g. historic case volume) and operating room (OR) efficiency times for lower extremity joint arthroplasty cases. The primary outcome was time from patient in the OR to anesthesia ready (i.e. after spinal or general anesthesia induction was complete). The secondary outcomes included time from anesthesia ready to surgical incision, and time from incision to closing completed. Mixed effects linear regression was performed, in which the random effect was the anesthesiology attending provider. There were 4,575 patients undergoing hip or knee arthroplasty included. There were 82 unique anesthesiology providers, in which the median [quartile] frequency of cases performed was 79 [45, 165]. On multivariable mixed effects linear regression - in which the primary independent variable (anesthesiologist case volume history for joint arthroplasty anesthesia) was log-transformed - the estimate for log-transformed case volume was - 0.91 (95% confidence interval [CI] -1.62, -0.20, P = 0.01). When modeling time from incision to closure complete, the estimate for log-transformed case volume was - 2.07 (95% -3.54, -0.06, P = 0.01). Thus, when comparing anesthesiologists with median case volume (79 cases) versus those with the lowest case volume (10 cases), the predicted difference in times added up to only approximately 6 min. If the purpose of faster anesthesia workflows was to open up more OR time to increase surgical volume in a given day, this study does not support the supposition that anesthesiologists with higher joint arthroplasty case volume would improve throughput.

Diagnostic accuracy of sonication fluid cultures from prosthetic components in periprosthetic joint infection: an updated diagnostic meta-analysis

BACKGROUND

Periprosthetic joint infection (PJI) is the most serious complication following total joint arthroplasty (TJA) and has a significant impact on patients and the national healthcare system. To date, the diagnosis of PJI is still confronted with dilemmas. The present study investigated the validity of sonication fluid culture (SFC) for removing implants in the diagnosis of PJI after joint replacement.

METHODS

From database establishment to December 2020, relevant literature was retrieved from the PubMed, Web of Science, Embase and Cochrane Library databases. Two reviewers independently performed quality assessment and data extraction to calculate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), area under the curve (AUC) and diagnostic odds ratio (DOR) to evaluate the diagnostic value of overall SFC for PJI.

RESULTS

A total of 38 eligible studies including 6302 patients were selected in this study. The pooled sensitivity, specificity, PLR, NLR, and DOR of SFC for PJI diagnosis were 0.77 (95% confidence interval [CI], 0.76-0.79), 0.96 (95% CI, 0.95-0.96), 18.68 (95% CI, 11.92-29.28), 0.24 (95% CI, 0.21-0.29), and 85.65 (95% CI, 56.46-129.94), respectively, while the AUC was 0.92.

CONCLUSION

This meta-analysis showed that SFC was of great value in PJI diagnosis, and the evidence of SFC on PJI was more favorable but not yet strong. Therefore, improvement of the diagnostic accuracy of SFC is still necessary, and the diagnosis of PJI continues to warrant a multiplex approach before and during a revision procedure.

Bi-planar calibration method for templating of hip joint arthroplasty: phantom study and proof of concept

PURPOSE

Calibration of radiographs is a critical step in digital templating for hip arthroplasty. Calibration errors of > 1.5% lead to over- or undersizing of the templated implants and may affect logistics and patient safety. Contemporary calibration methods are known to be imprecise with average errors of 6.5% and wide variance. A novel bi-planar radiograph-based calibration method is proposed, and a phantom study was conducted as proof of concept.

METHODS

A spherical external calibration marker (ECM) is placed in front of the pubic symphysis of a pelvic bone model at twelve different positions. For each marker position, standard anteroposterior radiographs and four corresponding lateral radiographs with different degrees of rotation (0°-30°) are taken (overall, 60 radiographs). Calibration factors are calculated for an internal calibration marker (ICM) at the centre of the right hip (reference) and the ECM using a novel algorithm. Rotation and marker positions simulate foreseeable use errors and misplacements and aim to test robustness of the method against these errors.

RESULTS

ECM calibration factor was 125.9% (range 124.7-127.2), and the mean ICM calibration factor was 126.6% (range 126.2-127.1) ([Formula: see text]). Four images (8.3%) were beyond the 1% error threshold (all with 30° rotation). The mean difference was 0.79% (SD 0.49).

CONCLUSION

The bi-planar method precisely predicts the true calibration factor of the hip joint plane under various conditions. In lateral radiographs, rotation of up to 20° did not adversely affect the precision and all images had calibration errors below the threshold for clinical significance.

A Retrospective Study of the Perioperative Period Management of Joint Arthroplasty in Patients with Chronic Kidney Disease

OBJECTIVE

With the rising prevalence of chronic kidney disease (CKD) and the increasing demand for joint arthroplasty, the management of CKD patients in the perioperative period of joint arthroplasty has become an issue worthy of attention for orthopedic surgeons. This study aimed to explore comprehensive perioperative period management strategies for CKD patients.

METHODS

From March 2017 to August 2022, 62 patients who underwent joint arthroplasty in our hospital were included in a retrospective study, including 31 CKD patients (mean age 69.8 ± 13.4 years old) and 31 non-CKD patients (mean age 69.4 ± 14.2 years old). The outcome indicators were analyzed, including serum urea, serum creatinine, blood uric acid, hematocrit, and hemoglobin.

RESULTS

All patients included in the retrospective study had an average preoperative preparation time of 4.3 ± 2.6 days and an average hospitalization time of 11.0 ± 7.3 days. There were no significant differences in the changes in the serum urea values between the preoperative and postoperative measurements in the CKD patients or in the serum creatinine values and blood uric acid values (P > 0.05). The hemoglobin value in postoperative measurements was lower than in preoperative measurements in the CKD patients (P < 0.05). The hematocrit value in postoperative measurements was lower than in preoperative measurements in the CKD patients (P < 0.001).

CONCLUSION

Patients with CKD have distinct characteristics compared to non-CKD patients, and they generally have a higher risk for postoperative complications and adverse events. Recognition of risk factors, suitable timing of surgery, the undertaking of protective strategies, and proper management of complications are vital for managing CKD patients in the perioperative period of joint arthroplasty.

The efficacy of patient specific instrumentation (PSI) in total hip arthroplasty (THA): A systematic review and meta-analysis

Background

Patient-specific instrumentation (PSI) has been suggested to reduce improper component positioning, though the effectiveness of PSI in total hip arthroplasty (THA) remains inconclusive. The purpose of this study was to evaluate the radiographic parameters and clinical outcomes comparing PSI and standard instrumentation (SI).

Methods

This systematic review and meta-analysis was conducted in accordance with the 2020 PRISMA statement and was registered on PROSPERO. PubMed, Embase, Scopus, Google Scholar, and ClinicalTrials.gov were searched for relevant studies pertaining to the use of PSI in THA. Inclusion criteria included PSI used in THA, PSI was directly compared to SI, and publication in English. Exclusion criteria included non-primary THA, review articles, abstracts, book chapters, and animal models.

Results

2,458 studies were initially identified, with 13 studies (677 THAs: 338 controls, 339 PSI) meeting all criteria. PSI was favored for the deviation from the preoperative plan for acetabular cup position for anteversion (p = 0.04) and inclination (p = 0.0002); risk of acetabular cup positioning outside the Lewinnek safe zone for anteversion (p = 0.005) and inclination (p < 0.0001); and postoperative Harris Hip Score (p = 0.0002). No significant differences were found for the deviation from the preoperative plan for femoral stem position for anteversion (p = 0.74) or varus/valgus (p = 0.15); intraoperative time (p = 0.55); or intraoperative blood loss (p = 0.62).

Conclusion

The use of PSI in THA is effective in improving acetabular component positioning and postoperative functional outcomes, without increasing intraoperative time or blood loss, compared to SI.

Feasibility of a preoperative strengthening exercise program on postoperative function in patients undergoing hip or knee arthroplasty: a pilot randomized controlled trial

BACKGROUND

There are conflicting results on the effect of preoperative exercise programs on long-term function and little evidence on short-term function. The aim is to assess the feasibility of a preoperative strengthening exercise program in patients undergoing hip or knee joint arthroplasty in terms of trial design, recruitment, and follow-up rates.

METHODS

A randomized controlled feasibility study with patients undergoing hip or knee joint arthroplasty. Patients were randomized to a preoperative strengthening exercise program or standard of care. Feasibility outcome measures were recruitment rate (≥ 50%) and loss to follow-up (≤ 15%).

RESULTS

Of the 129 eligible participants, 63 participants consented to participate in the study (49%), and 27 were successfully randomized prior to surgery (43%). All 27 participants completed the baseline assessment. Of these, 6 (22%) had surgery during the exercise period. Of the remaining 21 participants, 20 (95%) completed the pre-surgery assessment. The study was terminated before five participants could be eligible for the 6-month assessment. Sixteen (76%) participants completed the 6-week post-surgery assessment. Twelve participants completed the 6-month assessment (75%).

CONCLUSION

Given the recruitment rate, randomization barriers, and study participant loss to follow-up, the study was discontinued since it was not considered feasible in this current form at our clinical site despite modifications made to the protocol. Future investigations into a modified intervention via telerehabilitation should be explored.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03483519 . Retrospectively registered in March 2018.

Explaining regional variation in elective hip and knee arthroplasties in Finland 2010 - 2017-a register-based cohort study

Background

A persistent research finding in industrialised countries has been regional variation in medical practices including elective primary hip and knee arthroplasty. The aim of the study was to examine regional variations in elective total hip and knee arthroplasties over time, and the proportions of these variations which can be explained by individual level or area-level differences in need.

Methods

We obtained secondary data from the Care Register for Health Care to study elective primary hip and knee arthroplasties in total Finnish population aged 25 + years between 2010 and 2017. Two-level Poisson regression models – individuals and hospital regions – were used to study regional differences in the incidence of elective hip and knee arthroplasties in two time periods: 2010 − 2013 and 2014 − 2017. The impact of several individual level explanatory factors (age, socioeconomic position, comorbidities) and area-level factors (need and supply of operations) was measured with the proportional change in variance. Predictions of incidence were measured with incidence rate ratios. The relative differences in risk of the procedures in regions were described with median rate ratios.

Results

We found small and over time relatively stable regional variation in hip arthroplasties in Finland, while the variation was larger in knee arthroplasties and decreased during the study period. In 2010 − 2013 individual socioeconomic variables explained 10% of variation in hip and 4% in knee arthroplasties, an effect that did not emerge in 2014 − 2017. The area-level musculoskeletal disorder index reflecting the need for care explained a further 44% of the variation in hip arthroplasties in 2010 − 2013, but only 5% in 2014 − 2017 and respectively 22% and 25% in knee arthroplasties. However, our final models explained the regional differences only partially.

Conclusions

Our results suggest that eligibility criteria in total hip and knee arthroplasty are increasingly consistent between Finnish hospital districts. Factors related to individual level and regional level need both had an important role in explaining regional variations. Further study is needed on the effect of health policy on equity in access to care in these operations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08305-7.

Hepatitis C virus infection increases the risk of adverse outcomes following joint arthroplasty: A meta-analysis of observational studies

BACKGROUND

Whether hepatitis C virus (HCV)-positive patients are at risk for increased complications and long hospital stay following total joint arthroplasty (TJA) remains unclear. Therefore we performed a meta-analysis aiming to answer the following question: (1) are there differences in postoperative complications including joint infection and mortality between patients with or without hepatitis C following TJAs? (2) Are patients without HCV be associated with less blood loss, shorter hospital stay, lower readmission rate, higher function scores, lower revision and reoperation rates than patients with HCV?

METHODS

A meta-analysis was conducted to pool data and quantitatively assessing the association between HCV infection and risks for adverse postoperative outcomes. A systematic search of all published studies concerning HCV and TJA was performed in five bibliographic databases, including PubMed, EMBASE, China National Knowledge Infrastructure, Web of Science, and the Cochrane Library databases. Random-effects meta-analysis of odds ratios (OR) was accomplished according to the classification of adverse events, subgroup analyses were performed based on surgery type.

RESULTS

Fifteen eligible observational studies were included with a sample size of 9,788,166 patients. Overall pooled data revealed the increased risk of overall complications, including medical and surgical complications, in HCV-positive patients undergoing TJA compared with than in HCV-negative people (OR 1.57; 95%CI: 1.44-1.71 [p<0.00001]). Joint infections were highly common in HCV-positive patients undergoing lower-extremity TJA (OR 2.06; 95%CI: 1.73-2.47 [p<0.00001]). Furthermore, HCV infections were associated with high rates of reoperations and revisions (OR 1.47; 95%CI: 1.40-1.55 [p<0.00001]).

CONCLUSIONS

Patients with hepatitis C have an increased risk of adverse outcomes post-TJA and a high risk of reoperation and revision that is partially attributed to postoperative complications, particularly joint infections.

LEVEL OF EVIDENCE

III; systematic review and meta-analysis.

Serum D-lactate, a novel serological biomarker, is promising for the diagnosis of periprosthetic joint infection

Background

Although many markers are used for diagnosis of periprosthetic joint infection (PJI), serological screening and diagnosis for PJI are still challenging. We evaluated the performance of serum D-lactate and compared it with ESR, coagulation-related biomarkers and synovial D-lactate for the diagnosis of PJI.

Methods

Consecutive patients with preoperative blood and intraoperative joint aspiration of a prosthetic hip or knee joint before revision arthroplasty were prospectively included. The diagnosis of PJI was based on the criteria of the Musculoskeletal Infection Society, and the diagnostic values of markers were estimated based on receiver operating characteristic (ROC) curves by maximizing sensitivity and specificity using optimal cutoff values.

Results

Of 52 patients, 26 (50%) were diagnosed with PJI, and 26 (50%) were diagnosed with aseptic failure. ROC curves showed that serum D-lactate, fibrinogen (FIB) and ESR had equal areas under the curve (AUCs) of 0.80, followed by D-dimer and fibrin degradation product, which had AUCs of 0.67 and 0.69, respectively. Serum D-lactate had the highest sensitivity of 88.46% at the optimal threshold of 1.14 mmol/L, followed by FIB and ESR, with sensitivities of 80.77% and 73.08%, respectively, while there were no significant differences in specificity (73.08%, 73.08% and 76.92%, respectively).

Conclusion

Serum D-lactate showed similar performance to FIB and ESR for diagnosis of PJI. The advantages of serum D-lactate are pathogen-specific, highly sensitive, minimally invasive and rapidly available making serum D-lactate useful as a point-of-care screening test for PJI.

Impact of enhanced recovery pathways on safety and efficacy of hip and knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Over the past decades, clinical pathways (CPs) for hip and knee arthroplasty have been strongly and continuously evolved based on scientific evidence and innovation.

AIM

The present systematic review, including meta-analysis, aimed to compare the safety and efficacy of enhanced recovery pathways (ERP) with regular pathways for patients with hip and/or knee arthroplasty.

METHODS

A literature search in healthcare databases (Embase, PubMed, Cochrane Library, CINAHL, and Web of Science) was conducted from inception up to June 2018. Relevant randomized controlled trials as well as observational studies comparing ERP, based on novel evidence, with regular or standard pathways, prescribing care as usual for hip and/or knee arthroplasty, were included. The effect of both CPs was assessed for (serious) adverse events [(S)AEs], readmission rate, length of hospital stay (LoS), clinician-derived clinical outcomes, patient reported outcome measures (PROMs), and financial benefits. If possible, a meta-analysis was performed. In case of considerable heterogeneity among studies, a qualitative analysis was performed.

RESULTS

Forty studies were eligible for data extraction, 34 in meta-analysis and 40 in qualitative analysis. The total sample size consisted of more than 2 million patients undergoing hip or knee arthroplasty, with a mean age of 66 years and with 60% of females. The methodological quality of the included studies ranged from average to good. The ERP had lower (S)AEs [relative risk (RR): 0.9, 95% confidence interval (CI): 0.8-1] and readmission rates (RR: 0.8, 95%CI: 0.7-1), and reduced LoS [median days 6.5 (0.3-9.5)], and showed similar or improved outcomes for functional recovery and PROMs compared to regular pathways. The analyses for readmission presented a statistically significant difference in the enhanced recovery pathway in favor of knee arthroplasties (P = 0.01). ERP were reported to be cost effective, and the cost reduction varied largely between studies (€109 and $20573). The overall outcomes of all studies reported using Grading of Recommendation, Assessment, Development and Evaluation, presented moderate or high quality of evidence.

CONCLUSION

This study showed that implementation of ERP resulted in improved clinical and patient related outcomes compared to regular pathways in hip and knee arthroplasty, with a potential reduction of costs.

Unplanned intubation after total hip and total knee arthroplasty: Assessing preoperative risk factors

OBJECTIVE

The purpose of this study is to assess preoperative patient attributes as risk factors for unplanned intubation after primary total knee and total hip arthroplasty.

METHODS

This was a retrospective analysis of data collected from the National Surgical Quality Improvement Program (NSQIP) database. Patients undergoing Total Hip Arthroplasty (THA) or Total Knee Arthroplasty (TKA) who experienced postoperative intubation were included in the study. A multivariate regression was used to assess preoperative characteristics as risk factors for postoperative intubation.

RESULTS

Multivariate regression determined that perioperative transfusion of packed RBC's, cardiac comorbidities, patients older than 73, dyspnea with moderate exertion, dyspnea while at rest, diabetes mellitus requiring medical therapy, pulmonary comorbidities, current dialysis usage, body mass index greater than 29.9, and current smoker within the last year were variables associated with an increased risk of unplanned intubation after THA. Additionally, multivariate regression determined that anemia, perioperative transfusion of packed RBC's, cardiac comorbidities, patients older than 73, dyspnea with moderate exertion, diabetes mellitus requiring medical therapy, pulmonary comorbidities, and current dialysis usage were associated with unplanned intubation after TKA.

CONCLUSION

This study identifies numerous risk factors for intubation after THA or TKA.

Corneal Abrasions in Total Joint Arthroplasty

Introduction

Corneal abrasion (CA) is the most common ocular complication in patients undergoing nonocular surgery. Corneal abrasions can be caused by a variety of mechanisms, the most common being drying of the cornea due to reduced tear secretions, loss of eyelid reflex, and the loss of pain recognition during surgery. Though CA heals well with eye lubricants, it can result in significant ocular pain and some cases may go on to develop ocular complications. With the current switch to outpatient total joint replacement, CA could potentially lead to discharge delays.

Materials and Methods

We examined the results of a quality improvement project to reduce CA during general anesthesia to determine the rates of CA during hip and knee total joint replacement. We compared rates of CA for 6 months before and 6 months after the intervention.

Results

A total of 670 hip and knee arthroplasty procedures were performed during this period. Two events of CA occurred, one occurred before and one after the intervention to decrease eye injuries. Both incidences occurred during total hip arthroplasty (THA) procedures with the patient in the lateral decubitus position and recovered without long-term deficit.

Discussion

Surgeons and anesthesiologists alike should be cognizant of this avoidable complication and take precaution to protect the eyes during surgery, especially during THA when the patient is placed in the lateral decubitus position.

Conclusion

Corneal abrasion during total joint arthroplasty is a rare complication and is infrequently addressed in the literature. CA is mostly self-limiting, however, but may lead to patient dissatisfaction and to delays if same-day discharge is attempted. Preventative measures and attentive care may help reduce the incidence of CA in patients undergoing total joint arthroplasty. The lateral decubitus position and longer surgeries times are risk factors for CA.

Enormous Articular Hemorrhage Following Arthroscopy, Total Joint Replacement and other Surgical Operations in Hemophilic Patients due to Arterial Pseudoaneurysms: Diagnosis and Treatment

Pseudoaneurysms in hemophilic patients are unusual. We must have a suspicion when the patient has suffered an arterial trauma (following arthroscopy, total joint replacement and other surgical operations). Pseudoaneurysms may take place in any anatomical zone where there has been trauma. The diagnosis must be verified by duplex ultrasonography (US), standard angiogram, computed tomography angiogram or magnetic resonance angiography. There are diverse alternatives for the management of arterial pseudoaneurysms. Small pseudoaneurysms can be solved with conservative noninterventional management. It includes outside pressing, US probe pressing or US-guided thrombin injections. In larger pseudoaneurysms, endovascular methods, such as coil embolization, are now preferred. If the aforesaid methods are unsuccessful, standard surgical management with simple ligation or arterial reconstruction must be carried out. We must suspect a pseudoaneurysm when, following an arterial trauma, there is severe bleeding that does not stop with appropriate management with intravenous injection of the insufficient coagulation factor. The diagnosis has to be verified by imaging. Endovascular methods, such as coil embolization, are now preferred by the majority of physicians. The diagnosis and managment of an arterial pseudoaneurysm must be carried promptly to avert adverse events.

Effectiveness and Safety of Tourniquet Application Strategies in Total Knee Arthroplasty: a Meta-analysis

BACKGROUND

We conducted the present meta-analysis to assess the effectiveness and safety of long-duration tourniquet and short-duration tourniquet for patients with total knee arthroplasty (TKA).

METHODS

Published randomized controlled trials (RCTs) were identified from the following electronic databases: PubMed, Embase, Web of Science and Cochrane Library from inception to January 1, 2021. Studies comparing long-duration tourniquet and short-duration tourniquet in total knee arthroplasty were included. Either a random-effects model or a fixed-effects model was used for meta-analysis depending on the heterogeneity. Statistical analysis was assessed using RevMan 5.3 software.

RESULTS

A total of 8 RCTs with a total of 484 patients were eligible and ultimately included in the meta-analysis. Compared with patients in the long-duration tourniquet, those in the short-duration tourniquet were significantly correlated with postoperative drainage volume (WMD = -71.85, 95% CI - 76.52 to - 67.17, P = 0.31), but an increased risk of total blood loss (WMD = 68.13, 95% CI 5.15-131.12, P = 0.03) and intraoperative blood loss (WMD = 137.13, 95% CI 69.06-205.20, P < 0.00001). Two groups showed no significant difference in operation time, visual analogue scale score of knee in early, transfusion rate and incidence of deep venous thrombosis.

CONCLUSIONS

Our meta-analysis suggested that the short-duration tourniquet in TKA significantly decreased the postoperative drainage volume, increased the total blood loss and intraoperative blood loss. However, it did not marked decrease the occurrence of transfusion rate. Although the incidence of deep venous thrombosis was reduced in some study, it was not statistically significant. Additional high quality RCTs are needed to identify the hypothesis. Therefore, we recommend prolonged use of tourniquets during TKA surgery.

Appropriateness of transthoracic echocardiography in preoperative elective joint arthroplasty patients

Elective joint arthroplasty is a commonly performed procedure with postoperative cardiovascular complications occurring in up to 3% of elderly patients. Preoperative cardiac evaluation, including transthoracic echocardiography, may improve risk stratification and optimise perioperative outcomes in patients having non-cardiac surgery.This study aimed to investigate the frequency, indications, appropriateness and consequences of preoperative transthoracic echocardiography in elective joint arthroplasty patients. A one-year retrospective audit was conducted for patients who had elective joint arthroplasties performed at St Vincent's Hospital Melbourne. Patient demographics, transthoracic echocardiography indication, time between transthoracic echocardiography being ordered, performed and its impact on date of surgery were obtained via database and manual chart review. Appropriateness of transthoracic echocardiography was determined in accordance with international guidelines. This study analysed 609 elective joint arthroplasties. Of these, 116 (19%) already had a recent transthoracic echocardiography. Of the remaining 493 patients, 192 (39%) received a resting transthoracic echocardiography. Only 92 (48%) of the transthoracic echocardiography's ordered were deemed appropriate. Transthoracic echocardiography resulted in a significant delay of 31 days in time to surgery.This study indicates that almost 40% of elective joint arthroplasty patients with no recent echocardiogram are having a resting transthoracic echocardiography as part of their preoperative assessment. In 52% of cases, these are not clearly appropriate and result in delays to surgery.

Do standards of care and early outcomes of periprosthetic fractures change during the COVID-19 pandemic? A multicentre study

BACKGROUND

Periprosthetic fractures (PPFs) are a growing matter for orthopaedic surgeons, and patients with PPFs may represent a frail target in the case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The purpose of this study is to investigate whether hospital reorganisations during the most severe phase of the SARS-CoV-2 pandemic affected standards of care and early outcomes of patients treated for PPFs in Northern Italy.

MATERIALS AND METHODS

Data were retrieved from a multicentre retrospective orthopaedics and traumatology database, including 14 hospitals. The following parameters were studied: demographics, results of nasopharyngeal swabs, prevalence of coronavirus disease 2019 (COVID-19), comorbidities, general health status (EQ-5D-5L Score), frailty (Clinical Frailty Scale, CFS), pain (visual analogue scale, VAS), anaesthesiologic risk (American Society of Anaesthesiology Score, ASA Score), classification (unified classification system, UCS), type of operation and anaesthesia, in-hospital and early complications (Clavien-Dindo Classification, CDC), and length of stay (LOS). Data were analysed by means of descriptive statistics. Out of 1390 patients treated for any reason, 38 PPFs were included.

RESULTS

Median age was 81 years (range 70-96 years). Twenty-three patients (60.5%) were swabbed on admission, and two of them (5.3%) tested positive; in three patients (7.9%), the diagnosis of COVID-19 was established on a clinical and radiological basis. Two more patients tested positive post-operatively, and one of them died due to COVID-19. Thirty-three patients (86.8%) presented a proximal femoral PPF. Median ASA Score was 3 (range, 1-4), median VAS score on admission was 3 (range, 0-6), median CFS was 4 (range, 1-8), median EQ-5D-5L Score was 3 in each one of the categories (range, 1-5). Twenty-three patients (60.5%) developed post-operative complications, and median CDC grade was 3 (range, 1-5). The median LOS was 12.8 days (range 2-36 days), and 21 patients (55.3%) were discharged home.

CONCLUSIONS

The incidence of PPFs did not seem to change during the lockdown. Patients were mainly elderly with comorbidities, and complications were frequently recorded post-operatively. Despite the difficult period for the healthcare system, hospitals were able to provide effective conventional surgical treatments for PPFs, which were not negatively influenced by the reorganisation. Continued efforts are required to optimise the treatment of these frail patients in the period of the pandemic, minimising the risk of contamination, and to limit the incidence of PPFs in the future.

LEVEL OF EVIDENCE

IV.

Reliability of circulating fibrinogen in the diagnosis of prosthesis-related infections: a systematic review and meta-analysis

Background

Fibrinogen (FIB) has recently been used as a biomarker to diagnose periprosthetic joint infection (PJI), but its reliability is still questionable. The aim of this study was to investigate the accuracy of FIB in the diagnosis of PJI after joint replacement.

Methods

We searched for literatures published in PubMed, EMBASE, and the Cochrane Library from the time of database inception to September 2020 and screened the studies according to the inclusion criteria. Then, we calculated the diagnostic parameters of FIB, including the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), area under the curve (AUC), and diagnostic odds ratio (DOR). In addition, we implemented subgroup analyses to identify the sources of heterogeneity.

Results

Seven studies including 1341 patients were selected in our meta-analysis. The pooled sensitivity, specificity, PLR, NLR, and DOR of FIB for PJI diagnosis were 0.78 (95% confidence interval [CI], 0.73–0.82), 0.83 (95% CI, 0.81–0.86), 4.60 (95% CI, 3.30–6.42), 0.24 (95% CI, 0.18–0.34), and 20.13 (95% CI, 14.80–27.36), respectively, while the AUC was 0.896.

Conclusion

The present study indicated that FIB was a reliable detection method and might be introduced into the diagnostic criteria for PJI. However, more robust studies are still needed to confirm the current findings, because most of the included studies were retrospective and had small sample sizes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02171-x.

A critical review of weight loss recommendations before total knee arthroplasty

OBJECTIVE

Increased infection risk after total knee arthroplasty (TKA) in patients with a higher body mass index (BMI), particularly a BMI ≥40kg/m², suggests that BMI reduction (through weight loss) prior to TKA may be important. However, the impact of weight loss on TKA risk reduction is unclear. Furthermore, weight loss could have detrimental consequences with respect to muscle loss and development of sarcopenic obesity, whereby a potential weight loss paradox in adults with advanced knee OA and obesity may be present. Using a critical review approach, we examined the current evidence supporting weight loss in adults with obesity and advanced knee osteoarthritis (OA). We focused on three key areas: (1) TKA complication risk with severe obesity compared to obesity (BMI ≥40kg/m² versus 30.0-39.9kg/m²); (2) weight loss recommendations for individuals with advanced knee OA; and (3) TKA outcomes after pre-surgical weight loss.

METHODS

Medline and CINAHL databases were examined from Jan 2010 to May 2020 to identify high-level and/or clinically-influential evidence (systematic reviews, meta-analyses and clinical practice guidelines).

RESULTS

The literature does not show a clear relationship between weight loss and reduction in TKA complications, and no indication that a patients' individual risk is lowered by reducing their BMI from a threshold of ≥40kg/m² to ≤39.9kg/m². Studies that have found a benefit of weight loss for knee OA have not included patients with higher BMIs (≥40kg/m²) or more advanced knee OA. Furthermore, there is unclear evidence of a benefit of pre-surgical weight loss on TKA outcomes. These are important evidence gaps, suggesting that recommendations for BMI reduction prior to TKA should be tempered by the current uncertainty in the literature.

CONCLUSION

Evidence to support a benefit of weight loss prior to TKA is lacking. Until knowledge gaps are clarified, it is recommended that practitioners consider individual patient needs and risk before recommending weight loss (and therefore BMI reduction).

Personalized estimation of one-year mortality risk after elective hip or knee arthroplasty for osteoarthritis

AIMS

To develop and validate patient-centred algorithms that estimate individual risk of death over the first year after elective joint arthroplasty surgery for osteoarthritis.

METHODS

A total of 763,213 hip and knee joint arthroplasty episodes recorded in the National Joint Registry for England and Wales (NJR) and 105,407 episodes from the Norwegian Arthroplasty Register were used to model individual mortality risk over the first year after surgery using flexible parametric survival regression.

RESULTS

The one-year mortality rates in the NJR were 10.8 and 8.9 per 1,000 patient-years after hip and knee arthroplasty, respectively. The Norwegian mortality rates were 9.1 and 6.0 per 1,000 patient-years, respectively. The strongest predictors of death in the final models were age, sex, body mass index, and American Society of Anesthesiologists grade. Exposure variables related to the intervention, with the exception of knee arthroplasty type, did not add discrimination over patient factors alone. Discrimination was good in both cohorts, with c-indices above 0.76 for the hip and above 0.70 for the knee. Time-dependent Brier scores indicated appropriate estimation of the mortality rate (≤ 0.01, all models).

CONCLUSION

Simple demographic and clinical information may be used to calculate an individualized estimation for one-year mortality risk after hip or knee arthroplasty (https://jointcalc.shef.ac.uk). These models may be used to provide patients with an estimate of the risk of mortality after joint arthroplasty. Cite this article: Bone Joint Res 2020;9(11):808-820.

The use of patient-reported outcome measures to guide referral for hip and knee arthroplasty

AIMS

To assess how the cost-effectiveness of total hip arthroplasty (THA) and total knee arthroplasty (TKA) varies with age, sex, and preoperative Oxford Hip or Knee Score (OHS/OKS); and to identify the patient groups for whom THA/TKA is cost-effective.

METHODS

We conducted a cost-effectiveness analysis using a Markov model from a United Kingdom NHS perspective, informed by published analyses of patient-level data. We assessed the cost-effectiveness of THA and TKA in adults with hip or knee osteoarthritis compared with having no arthroplasty surgery during the ten-year time horizon.

RESULTS

THA and TKA cost < £7,000 per quality-adjusted life-year (QALY) gained at all preoperative scores below the absolute referral thresholds calculated previously (40 for OHS and 41 for OKS). Furthermore, THA cost < £20,000/QALY for patients with OHS of ≤ 45, while TKA was cost-effective for patients with OKS of ≤ 43, since the small improvements in quality of life outweighed the cost of surgery and any subsequent revisions. Probabilistic and one-way sensitivity analyses demonstrated that there is little uncertainty around the conclusions.

CONCLUSION

If society is willing to pay £20,000 per QALY gained, THA and TKA are cost-effective for nearly all patients who currently undergo surgery, including all patients at and above our calculated absolute referral thresholds. Cite this article: Bone Joint J 2020;102-B(7):950-958.

Two-Stage Primary Arthroplasty of Native Hips and Knees That Had Previously Failed Treatment for Septic Arthritis: A Single-Center Experience

Background

Patients with a history of degenerative joint disease secondary to an acute or remote episode of septic arthritis of the native knee or hip present a unique challenge for the orthopaedic surgeon. This study describes our experience with two-stage primary arthroplasty for such patients.

Methods

We reviewed 42 patients with a history of septic arthritis treated with two-stage primary arthroplasty between 2008 and 2018. Patients were evaluated using modified Harris Hip Score, Knee Society Score (KSS), and KSS functional component (KSSF). Paired t-tests were used to compare changes for continuous variables within cohorts. Multivariate linear and logistic regression models were constructed to determine predictors of outcomes and complications.

Results

At a mean of 3.3-year follow-up, there were 14 (33.3%) complications and the infection cure rate was 95.2%. On average, patients improved in the modified Harris Hip Score (42.9 ± 11.8 vs 83.3 ± 11.1, P < .001), KSS (35.9 ± 16.9 vs 80.1 ± 16.6, P < .001), KSSF (38.0 ± 15.1 vs 71.5 ± 24.0, P < .001), knee flexion (90.9 ± 14.9 vs 100.5 ± 17.1), and hip flexion (73.8 ± 21.2 vs 102.1 ± 11.8, P < .001). Age (β: -0.78, P = .004) was independently associated with lower Harris Hip Score in the hip cohort. There were no independent predictors of the KSS or KSSF. The erythrocyte sedimentation rate (odds ratio: 1.07, P = .043) and C-reactive protein (odds ratio: 1.43, P = .018) at stage 2 were independently associated with a higher likelihood of complications at the final follow-up.

Conclusion

Patients with a history of native septic arthritis of the hip and knee, and secondary end-stage degenerative joint disease, showed significant postoperative improvements and a high rate of complications after two-stage primary total joint arthroplasty. Despite improvements, some patients may necessitate a third operation because of the incidence of reinfection and spacer exchange. This information should be used to counsel patients who present with this challenging clinical scenario.

Thermogenic diagnosis of periprosthetic joint infection by microcalorimetry of synovial fluid

Background

Synovial fluid culture is the standard investigation for the preoperative diagnosis of periprosthetic joint infection (PJI). However, the culture has limited sensitivity and requires several days until result. We evaluated the value of isothermal microcalorimetry for real-time diagnosis of PJI based on heat produced by microbial growth in synovial fluid.

Methods

Patients undergoing aspiration of prosthetic hip or knee joint before revision surgery were prospectively included between 2014 and 2015. The performance of microcalorimetry was compared to synovial fluid culture using McNemar’s chi-squared test. Pearson’s correlation coefficient was calculated for synovial fluid leukocyte count and microcalorimetric heat.

Results

Of 107 included patients (58 knee and 49 hip prosthesis), PJI was diagnosed in 46 patients (43%) and aseptic failure in 61 patients (57%) according to institutional criteria. In 26 PJI cases (56%) the pathogen grew in synovial fluid and intra-operative cultures. The sensitivity of synovial fluid culture and microcalorimetry was both 39% and the results were concordant in 98 patients (92%). In patients with PJI, microcalorimetry missed 4 pathogens which grew in synovial fluid culture, whereas culture missed 4 pathogens detected by microcalorimetry. A linear correlation (r = 0.366) was found between leukocyte count and microcalorimetric heat in synovial fluid (p < 0.001). The median time to positivity of microcalorimetry was 9 h (range, 1–64 h) vs. 3 days for cultures (range, 1–14 days).

Conclusion

Microcalorimetry of synovial fluid allows thermogenic diagnosis of periprosthetic joint infection in synovial fluid. The diagnostic performance of synovial fluid microcalorimetry is comparable to culture and delivers results considerably faster.

Trial registration

This prospective study was registered on August 21, 2015 with the public clinical trial identification NCT02530229.

Effect of urinary tract infection on the risk of prosthetic joint infection: A systematic review and meta-analysis

PURPOSE

Urinary tract infection (UTI) are very common in the general population, however it is unclear whether UTI is a risk factor of prosthetic joint infection (PJI). Our purposes were: (1) To determine whether UTI is a risk factor of PJI after joint replacement, and (2) to determine whether the microorganisms causing PJI and UTI are the same.

METHODS

PubMed, Web of Science, the Cochrane Library, and EMBASE were searched systematically for studies. The effect sizes of RR were calculated for included studies that reported raw counts with 95% CIs. The aim 1 of the study is a meta-analysis; the aim 2 is a systematic review.

RESULTS

The aim 1 indicated that the risk of PJI was significantly higher in the UTI group than in the control group (RR = 3.17; 95% CI, 2.19-4.59). The aim 2 indicated that the microorganisms of UTI and PJI were the same in the same patient, and these included Enterococcus faecalis, and Pseudomonas, which supports the theory of PJI occurring via the haematogenous route from the genitourinary tract that harbours bacteria in UTI.

CONCLUSION

This study identified UTI as being significantly associated with PJI after joint arthroplasty and PJI occurring via the haematogenous route from the genitourinary tract harbouring bacteria in UTI. Therefore, postponing surgery and even treating patients with known UTI preoperatively are recommended.

Global Perspectives on Arthroplasty of Hip and Knee Joints

There is a broad variation of implantation rates, indications, and types of prostheses used for hip and knee joint replacement procedures among different countries. The establishment of national joint registers has improved knowledge and quality of data related to joint implantation. Comparing reports of different national registries is crucial to determine potential variations in practices among surgeons and arthroplasty centers and to identify topics for future analysis. In this report, data from these registries in addition to manufacturer reports were used to evaluate procedure volumes and implants utilization trends of primary and revision total hip and knee replacement around the world.

Portable compression devices in total joint arthroplasty: poor outpatient compliance

Background

Aspirin and mechanical compression devices are approved means of venous thromboembolism (VTE) prophylaxis after total joint arthroplasty. Prior studies of mechanical compression pumps after joint arthroplasty have been limited to the inpatient setting. The purpose of this study was to evaluate outpatient compliance and utilization factors in a rural population after elective hip or knee arthroplasty.

Methods

Utilization for portable pneumatic compression pumps after joint arthroplasty was prospectively recorded (hours). Compliance was defined as the recommended 20 hours per day. A questionnaire 2 weeks postoperatively assessed factors that may contribute to noncompliance. Patients were followed up for 90 days postoperatively to record VTE events.

Results

Data were collected for 115 joint arthroplasty patients (50 hips, 65 knees). Postdischarge day one had the highest average usage at 13.2 hours/day (66.0%, range 0%-100%), but this number fell to 4.8 hours/day (24.0, range 0%-100%) by day 14. Patient compliance (>20 hours use/day) was highest on postdischarge day one at 40 patients (34.7%). By postdischarge day 14, patient compliance fell to 17 patients (14.8%). Difficulty using the pumps (P = .027) and pump-associated heat (P = .009) were significantly associated with patient compliance. A deep vein thrombosis and nonfatal pulmonary embolism were recorded in 2 separate patients.

Conclusions

This study demonstrated poor outpatient compliance with portable pneumatic compression devices. Poor compliance was related to pump heat and difficulty with pump use. Even with poor compliance, a low incidence of VTE events was observed.

Rates, causes, and types of readmissions after total joint arthroplasty

OBJECTIVES

The aim of the study was to investigate the causes and rates of readmissions within 90 days after primary and revision knee and hip arthroplasties.

PATIENTS AND METHODS

A total of 1,516 patients (290 males, 1,226 females; mean age 64.7±10.5 years; range, 21 to 91 years) who underwent primary total hip arthroplasty (THA), primary total knee arthroplasty (TKA), revision THA, and revision TKA between January 2013 and December 2014 were retrospectively analyzed. All readmissions within 90 days as of discharge dates of patients were analyzed and were categorized as planned readmissions related to the index admission, unplanned readmissions related to the index admission, planned readmissions unrelated to the index admission and unplanned readmissions unrelated to the index admission.

RESULTS

Readmission rate in the overall of study group was found to be 5.61%. This rate varied depending on the procedure applied, ranging between 2.35 and 6.74%. Unplanned readmissions related to the index admission within 90 days consisted of 60.0% of total readmissions. A total of 82.0% of readmissions within 90 days was due to surgical reasons. Planned readmissions unrelated to the index admission within 90 days were also frequently seen (31.76%). Totally 48.23% of total readmissions within 90 days occurred within the first 30 days. A total of 48.23% of the total readmissions and 58.82% of the readmissions which were unplanned and related to the index admission occurred within the first 30 days.

CONCLUSION

After knee and hip arthroplasties, readmissions occur due to various reasons. Therefore, it is of utmost importance to identify the readmission type in the evaluation of readmissions which may increase the effectiveness of precautions to be taken.

The cost-effectiveness of antibiotic-loaded bone cement versus plain bone cement following total and partial knee and hip arthroplasty

Background

Postoperative infection is one of the most prevalent complications following total joint arthroplasty (TJA). As such procedures become more prevalent, it is imperative that we develop new prophylactic methods to prevent the need for revision procedures. In recent years, surgeons have opted to use antibiotic-loaded bone cement (ALBC) rather than plain bone cement (PBC) in primary hip and knee replacements due to its theoretical potential of lowering infection rates. However, the cost-effectiveness of this intervention remains in question.Questions/Purposes: To determine the rate of infection and cost-effectiveness of antibiotic-loaded bone cement as compared to plain bone cement in hip and knee arthroplasty.

Patients and methods

We reviewed 4116 primary hip and knee arthroplasty cases performed between 2016 and 2018 at Morristown Medical Center in New Jersey. Data regarding demographics, complications, and any readmissions due to deep infection were collected retrospectively. During that time period there were a total of 4016 knee cases (423 ALBC, 3593 PBC) and 123 hip cases (63 ALBC, 60 PBC). The average cost for one bag of antibiotic-loaded bone cement and plain bone cement for hip and knee arthroplasty was $336.42 and $72.14, respectively. A statistical analysis was performed using Fisher's exact test; the National Healthcare Safety Network (NHSN) surgical site infection guidelines were used to distinguish between superficial and deep infections.

Results

Ten patients were readmitted due to deep infection, all of whom had undergone total knee arthroplasty. Of those cases, plain bone cement was used for the index procedure in seven instances and antibiotic-loaded cement was used in three. This resulted in an infection rate of 0.19% and 0.62%, respectively, p = 0.103. There was no statistically significant difference in infection rates between the two groups. A total of 778 bags of ALBC were used in 423 knee surgeries, and 98 bags of ALBC were used in 63 hip cases. The total cost for ALBC in TKA and THA procedures was $261,734.76 (778*336.42) and $32,969.16 (98*336.42), respectively. If PBC had been used during all index procedures, it would have resulted in a total savings of $231,509.28.

Conclusions

Antibiotic-loaded cement did not significantly reduce the rate of infection for either knee or hip arthroplasty. Thus, the routine use of antibiotic-loaded cement in primary hip and knee arthroplasty may be an unnecessary financial burden to the healthcare system. A larger sample size and a randomized controlled trial would help confirm our findings and would provide further information on the cost-effectiveness of ALBC cement versus PBC.Significance/Clinical Relevance: In this review of cases performed from 2016 to 2018 there was no statistically significant difference between the rate of infection and the need for revision surgeries for patients treated with ALBC versus PBC. As hospital systems continue to transition towards a bundled payment model, it becomes imperative for providers to reduce any unnecessary costs in order to increase quality and efficiency. We estimate that our hospital system could save nearly $120,000/year by using plain bone cement instead of antibiotic-loaded cement.

[Research progress of two-stage revision for periprosthetic joint infection after hip and knee arthroplasties]

Objective

To summarize the research progress of two-stage revision for periprosthetic joint infection (PJI) after hip and knee arthroplasties.

Methods

The related literature on two-stage revision for PJI was summarized, and the new progress in the choice of spacers, systemic antibiotic therapy, and risk factors were analyzed.

Results

Two-stage revision is a common way to treat infection after hip and knee arthroplasties. The types of spacers used in the one-stage operation are diverse and each has its own advantages and disadvantages. Non-articular spacers are mainly used for the patients with poor soft tissue conditions around the joints and severe bone defects. But the joint mobility is not good after the placement of the spacer. Articular spacers can restore the affected joint movement after operation, which is beneficial to the joint mobility after two-stage operation. The use of antibiotics is an indispensable part of the treatment process, and the effectiveness of short-term antibiotic treatment is similar to long-term treatment. Identifying the relevant risk factors that influence the prognosis of the two-stage revision can help preoperative management and reduce the recurrence rate of infection.

Conclusion

There are still controversies about the choice of spacers and systemic antibiotic therapy during the two-stage revision and treatment of PJI. The factors affecting the prognosis of the two-stage revision need to be explored and the further high-quality research is needed.

Technology-assisted rehabilitation following total knee or hip replacement for people with osteoarthritis: a systematic review and meta-analysis

BACKGROUND

To evaluate the effectiveness and safety of technology-assisted rehabilitation following total hip/knee replacement (THR/TKR).

METHODS

Six electronic databases were searched without language or time restrictions for relevant studies: MEDLINE, EMBASE, Cochrane Library, CINAHL, SPORTDiscus, Physiotherapy Evidence Database (PEDro); from inception to November 7th, 2018. Two reviewers independently applied inclusion criteria to select eligible randomised controlled trials (RCTs) that investigated the effectiveness of technology-based interventions, compared with usual care or no intervention for people undergoing THR/TKR. Two reviewers independently extracted trial details (e.g. patients' profile, intervention, outcomes, attrition and adverse events). Study methodological quality was assessed using the PEDro scale. Quality of evidence was critically appraised using the Grading of Recommendations, Assessment, Development and Evaluation approach.

RESULTS

We identified 21 eligible studies assessing telerehabilitation, game- or web-based therapy. There were 17 studies (N = 2188) in post-TKR rehabilitation and 4 studies (N = 783) in post-THR rehabilitation. Compared to usual care, technology-based intervention was more effective in reducing pain (mean difference (MD): - 0.25; 95% confidence interval (CI): - 0.48, - 0.02; moderate evidence) and improving function measured with the timed up-and-go test (MD: -7.03; 95% CI: - 11.18, - 2.88) in people undergoing TKR. No between-group differences were observed in rates of hospital readmissions or treatment-related adverse events (AEs) in those studies.

CONCLUSION

There is moderate-quality of evidence showed technology-assisted rehabilitation, in particular, telerehabilitation, results in a statistically significant improvement in pain; and low-quality of evidence for the improvement in functional mobility in people undergoing TKR. The effects were however too small to be clinically significant. For THR, there is very limited low-quality evidence shows no significant effects.

Ranawat Award: Elective joint arthroplasty outcomes improve in malnourished patients with nutritional intervention: a prospective population analysis demonstrates a modifiable risk factor

AIMS

To date, no study has demonstrated an improvement in postoperative outcomes following elective joint arthroplasty with a focus on nutritional intervention for patients with preoperative hypoalbuminaemia. In this prospective study, we evaluated differences in the hospital length of stay (LOS), rate of re-admission, and total patient charges for a malnourished patient study population who received a specific nutrition protocol before surgery.

PATIENTS AND METHODS

An analytical report was extracted from the electronic medical record (EMR; Epic, Verona, Wisconsin) of a five-hospital network joint arthroplasty patient data set between 2014 and 2017. A total of 4733 patients underwent joint arthroplasty and had preoperative measurement of albumin levels: 2220 at four hospitals and 2513 at the study hospital. Albumin ≤ 3.4 g/l, designated as malnutrition, was found in 543 patients (11.5%). A nutritional intervention programme focusing on a high-protein, anti-inflammatory diet was initiated in January 2017 at one study hospital. Hospital LOS, re-admission rate, and 90-day charges were compared for differential change between patients in study and control hospitals for all elective hip and knee arthroplasty patients, and for malnourished patients over time as the nutrition intervention was implemented.

RESULTS

Malnourished patients with nutritional intervention at the study hospital had shorter hospital LOS beginning in 2017 than malnourished patients at control hospitals during the same period (p = 0.04). Similarly, this cohort had significantly lower primary hospitalization charges, charges associated with hospital re-admissions, and 90-day total charges (p < 0.001). Inclusion of covariant potential confounders (age, anaemia, diabetes, and obesity) did not alter the conclusions of the primary statistical analysis.

CONCLUSION

Joint arthroplasty outcomes were positively affected in study patients with low albumin when a high-protein, anti-inflammatory diet was encouraged. Elective surgery was neither cancelled nor delayed with a malnutrition designation. While the entire network population experienced improved postoperative outcomes, malnourished control patients did not experience this improvement. This study demonstrated that education on malnutrition can benefit patients. Cite this article: Bone Joint J 2019;101-B(7 Supple C):17-21.

A Prototype Patient-Maintained Propofol Sedation System Using Target Controlled Infusion for Primary Lower-Limb Arthroplasty

Each year, many operations in the UK are performed with the patient awake, without the use of general anaesthesia. These include joint replacement procedures, and in order to reduce patient anxiety, the supervising anaesthetist delivers the sedative propofol intravenously using a target-controlled infusion (TCI) device. However, it is clinically challenging to judge the required effect-site concentration of sedative for an individual patient, resulting in patient care issues related to over or under-sedation. To improve the process, patient-maintained propofol sedation (PMPS), where the patient can request an increase in concentration through a hand-held button, has been considered as an alternative. However, due to the proprietary nature of modern TCI pumps, the majority of PMPS research has been conducted using prototypes in research studies. In this work, a PMPS system is presented that effectively converts a standard infusion pump into a TCI device using a laptop with TCI software. Functionally, the system delivers sedation analogous to a modern TCI pump, with the differences in propofol consumption and dosage within the tolerance of clinically approved devices. Therefore, the Medicines and Healthcare products Regulatory Agency (MHRA) has approved the system as a safe alternative to anaesthetist-controlled TCI procedures. It represents a step forward in the consideration of PMPS as a sedation method as viable alternative, allowing further assessment in clinical trials.

Change in the cause of inpatient mortality after arthroplasty: a retrospective study

Background

Although arthroplasty has been proved to be a safe and effective procedure, data regarding inpatient mortality rates associated with arthroplasty in China is unclear. We aimed to investigate the inpatient mortality rate after arthroplasty and the determinants of mortality at our center to ensure improved perioperative management.

Methods

This retrospective study included all patients who underwent arthroplasty at our center. Clinical data of mortality patients were collected. The incidence and the causes of inpatient mortality after arthroplasty were analyzed.

Results

A total of 4176 total knee arthroplasties, 2164 total hip arthroplasties, and 1031 femoral head replacements were performed. A rapid growth in surgery volume was observed, and more than 50% of the surgeries were performed in the last 5 years. The overall inpatient mortality rate is 0.3%; however, the mortality rate even decreased in the last 5 years. The cause of death changed over time. Pneumonia has become the leading cause of death in the past 5 years instead of cardiovascular complications.

Conclusions

Arthroplasty is a safe and effective procedure associated with a relatively low inpatient mortality in China. And inpatient mortality does not increase as the growing surgery volume due to improvement of perioperative management. However, patients presenting with risk factors and those undergoing non-elective procedures demonstrated a relatively high incidence of postoperative complications, particularly pneumonia.

Antibacterial coating of implants: are we missing something?

Implant-related infection is one of the leading reasons for failure in orthopaedics and trauma, and results in high social and economic costs. Various antibacterial coating technologies have proven to be safe and effective both in preclinical and clinical studies, with post-surgical implant-related infections reduced by 90% in some cases, depending on the type of coating and experimental setup used. Economic assessment may enable the cost-to-benefit profile of any given antibacterial coating to be defined, based on the expected infection rate with and without the coating, the cost of the infection management, and the cost of the coating. After reviewing the latest evidence on the available antibacterial coatings, we quantified the impact caused by delaying their large-scale application. Considering only joint arthroplasties, our calculations indicated that for an antibacterial coating, with a final user's cost price of €600 and able to reduce post-surgical infection by 80%, each year of delay to its large-scale application would cause an estimated 35 200 new cases of post-surgical infection in Europe, equating to additional hospital costs of approximately €440 million per year. An adequate reimbursement policy for antibacterial coatings may benefit patients, healthcare systems, and related research, as could faster and more affordable regulatory pathways for the technologies still in the pipeline. This could significantly reduce the social and economic burden of implant-related infections in orthopaedics and trauma. Cite this article: C. L. Romanò, H. Tsuchiya, I. Morelli, A. G. Battaglia, L. Drago. Antibacterial coating of implants: are we missing something? Bone Joint Res 2019;8:199-206. DOI: 10.1302/2046-3758.85.BJR-2018-0316.

Anaesthetist-controlled versus patient-maintained effect-site targeted propofol sedation during elective primary lower-limb arthroplasty performed under spinal anaesthesia (ACCEPTS): study protocol for a parallel-group randomised comparison trial

BACKGROUND

The clinical efficacy of effect-site targeted patient-maintained propofol sedation (PMPS) compared to anaesthetist-controlled propofol sedation (ACPS) for patients undergoing awake joint replacement surgery is currently unknown. There is no commercially available medical device capable of delivering PMPS so we have designed and built such a device. We plan a clinical trial to compare PMPS to ACPS and to collect data relating to the safety of our prototype device in delivering sedation.

METHODS

The trial is an open-label, randomised, controlled superiority trial recruiting adults who are undergoing elective primary lower-limb arthroplasty with sedation by propofol infusion by effect-site targeting into two equal-sized parallel arms: PMPS and ACPS. The primary research objective is to compare the body-weight-normalised rate of propofol consumption when sedation for surgery on adults undergoing elective primary lower-limb arthroplasty under spinal anaesthesia is patient-maintained versus when it is anaesthetist-controlled. The study primary null hypothesis is that there is no difference in the rate of propofol consumption when sedation is patient-maintained versus anaesthetist-controlled.

DISCUSSION

This is the first trial to test the superiority of effect-site-targeted patient-maintained propofol sedation versus anaesthetist-controlled propofol sedation in terms of total propofol consumption during the sedation period. The results of this trial will help inform clinicians and device manufacturers of the clinical efficacy and safety of patient-maintained propofol sedation applied to a common operative setting.

TRIAL REGISTRATION

International Standard Randomised Controlled Trial Number Registry, ISRCTN29129799 . Prospectively registered on 12 June 2018.

Should postoperative haemoglobin and potassium levels be checked routinely following blood-conserving primary total joint arthroplasty?

AIMS

Despite declining frequency of blood transfusion and electrolyte supplementation following total joint arthroplasty, postoperative blood analyses are still routinely ordered for these patients. This study aimed to determine the rate of blood transfusion and electrolyte restoration in arthroplasty patients treated with a perioperative blood conservation protocol and to identify risk factors that would predict the need for transfusion and electrolyte supplementation.

PATIENTS AND METHODS

Patients undergoing primary total joint arthroplasty of the hip or knee between July 2016 and February 2017 at a single institution were included in the study. Standard preoperative and postoperative laboratory data were collected and reviewed retrospectively. A uniform blood conservation programme was implemented for all patients. Need for blood transfusion or potassium supplementation was determined through a coordinated decision by the care team. Rates of transfusion and supplementation were observed, and patient risk factors were noted.

RESULTS

The overall rate of blood transfusion was 1.06% in the study population of 1132 total joint arthroplasties performed in 1023 patients. Of the 12 patients requiring transfusion, 11 were female, ten occurred in patients undergoing total hip arthroplasty, and all 12 patients had a preoperative haemoglobin level less than 130 g/l. Operative duration and surgical blood loss were significantly greater in those patients requiring blood transfusion. Nearly all patients requiring transfusion had a history of, or risk factors for, cardiovascular disease. Potassium supplementation was required in 15.5% of the study cohort; 72% of these patients receiving potassium presented with a potassium level less than 4 mmol/l during preoperative testing, while the remaining 28% had a past medical history of either significant anaemia, cardiopulmonary, cardiovascular, or renal diseases that had required substantial medical management.

CONCLUSION

A consistent blood-conserving perioperative strategy effectively minimized need for blood transfusion in total joint arthroplasty patients below previously reported rates in the literature. We suggest that postoperative full blood counts and basic metabolic panels should not routinely be ordered in these patients unless their preoperative haemoglobin and potassium is below 130 g/dl or 4 mmol/l respectively, and they have medical comorbidities.

How wait-times, social media, and surgeon demographics influence online reviews on leading review websites for joint replacement surgeons

OBJECTIVE

With the growth and popularity of the internet, physician review websites are being utilized more frequently by patients to learn about and ultimately select their provider. These sites allow patients to comment on the care they received in a public forum for others to see. With outcome and "quality" measures being used to dictate reimbursement formulas; online patient reviews may affect a physician's compensation in the near future. Therefore, it is of paramount importance for physicians to understand how best to portray themselves on social media and other internet sites.

METHODS

In this retrospective study, we identified 145 arthroplasty surgeons via the AAHKS database. Then, surgeon data was collected from Healthgrades (HG) and Vitals (V). We identified if the surgeon had social media (SM) accounts by using google search. The number of ratings and comments, overall rating, reported wait-times and physician SM presence were analyzed with univariate, bivariate and multivariate analyses.

RESULTS

64% of surgeons had a SM presence, and younger surgeons with SM had lower distribution of wait-times. A SM presence correlated with significantly higher frequency of total ratings and comments. Both review sites showed that younger physicians with a SM presence had increased frequency of ratings and comments and a quicker office wait-times. SM presence did not impact the overall scores on either website.

CONCLUSION

Having SM presence is correlated with increased number of ratings and comments on physician review sites, possibly revealing an increased likelihood of these physicians encouraging their patients to engage with them via the internet. SM presence did not correlate with higher review scores, displaying that there are many complex factors that go into a physician score outside of SM and internet appearance. Future studies should explore patient comments on these sites to understand additional factors that may optimize a patient's experience.

The effect of multimorbidity on changes in health-related quality of life following hip and knee arthroplasty

Aims

The aim of this study was to assess the effect of multimorbidity on improvements in health-related quality of life (HRQoL) following total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Patients and Methods

Using data from a regional joint registry for 14 573 patients, HRQoL was measured prior and one year following surgery using the Oxford Hip Score (OHS) and Oxford Knee Score (OKS), and the 12-Item Short-Form Health Survey Physical and Mental Component Summary scores (PCS and MCS, respectively). Multimorbidity was defined as the concurrence of two or more self-reported chronic conditions. A linear mixed-effects model was used to test the effects of multimorbidity and the number of chronic conditions on improvements in HRQoL.

Results

Almost two-thirds of patients had multimorbidity, which adversely effected improvements in HRQoL. For THA, mean improvements in HRQoL scores were reduced by 2.21 points in OHS, 1.62 in PCS, and 4.14 in MCS; for TKA, the mean improvements were reduced by 1.71 points in OKS, 1.92 in PCS, and 3.55 in MCS (all p < 0.0001). An increase in the number of chronic conditions was associated with increasing reductions in HRQoL improvements.

Conclusion

Multimorbidity adversely effects improvements in HRQoL following THA and TKA. Our findings are relevant to healthcare providers focused on the management of patients with chronic conditions and for administrators reporting and monitoring the outcomes of THA and TKA. Cite this article: Bone Joint J 2018;100-B:1168-74.

Serum biomarkers in periprosthetic joint infections

OBJECTIVES

The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI.

METHODS

We searched two literature databases, using terms that encompass all hip and knee arthroplasty procedures, as well as PJI and statistical terms reflecting diagnostic parameters. The findings are summarized as a narrative review.

RESULTS

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were the two most commonly published serum biomarkers. Most evidence did not identify other serum biomarkers that are clearly superior to ESR and CRP. Other serum biomarkers have not demonstrated superior sensitivity and have failed to replace CRP and ESR as first-line screening tests. D-dimer appears to be a promising biomarker, but more research is necessary. Factors that influence serum biomarkers include temporal trends, stage of revision, and implant-related factors (metallosis).

CONCLUSION

Our review helped to identify factors that can influence serum biomarkers' level changes; the recognition of such factors can help improve their diagnostic utility. As such, we cannot rely on ESR and CRP alone for the diagnosis of PJI prior to second-stage reimplantation, or in metal-on-metal or corrosion cases. The future of serum biomarkers will likely shift towards using genomics and proteomics to identify proteins transcribed via messenger RNA in response to infection and sepsis.Cite this article:Bone Joint Res 2018;7:85-93.

Patterns and predictors of persistent opioid use following hip or knee arthroplasty

OBJECTIVE

The relationship between arthroplasty and long-term opioid use in patients with knee or hip osteoarthritis is not well studied. We examined the prevalence, patterns and predictors of persistent opioid use after hip or knee arthroplasty.

METHOD

Using claims data (2004-2013) from a US commercial health plan, we identified adults who underwent hip or knee arthroplasty and filled ≥1 opioid prescription within 30 days after the surgery. We defined persistent opioid users as patients who filled ≥1 opioid prescription every month during the 1-year postoperative period based on group-based trajectory models. Multivariable logistic regression was used to determine preoperative predictors of persistent opioid use after surgery.

RESULTS

We identified 57,545 patients who underwent hip or knee arthroplasty. The mean ± SD age was 61.5 ± 7.8 years and 87.1% had any opioid use preoperatively. Overall, 7.6% persistently used opioids after the surgery. Among patients who used opioids in 80% of the time for ≥4 months preoperatively (n = 3023), 72.1% became persistent users. In multivariable analysis, knee arthroplasty vs hip, a longer hospitalization stay, discharge to a rehabilitation facility, preoperative opioid use (e.g., a longer duration and greater dosage and frequency), a higher comorbidity score, back pain, rheumatoid arthritis, fibromyalgia, migraine and smoking, and benzodiazepine use at baseline were strong predictors for persistent opioid use (C-statistic = 0.917).

CONCLUSION

Over 7% of patients persistently used opioids in the year after hip or knee arthroplasty. Given the adverse health effects of persistent opioid use, strategies need to be developed to prevent persistent opioid use after this common surgery.

The role of routine screening in blood-borne pathogens in Chinese patients undergoing joint arthroplasty

Objectives

Surgeons face a substantial risk of infection because of the occupational exposure to blood-borne pathogens (BBPs) from patients undergoing high-risk orthopaedic procedures. This study aimed to determine the seroprevalence of four BBPs among patients undergoing joint arthroplasty in Shanghai, China. In addition, we evaluated the significance of pre-operative screening by calculating a cost-to-benefit ratio.

Methods

A retrospective observational study of pre-operative screening for BBPs, including hepatitis B and C viruses (HBV and HCV), human immunodeficiency virus (HIV) and Treponema pallidum (TP), was conducted for sequential patients in the orthopaedic department of a large urban teaching hospital between 01 January 2009 and 30 May 2016. Medical records were analysed to verify the seroprevalence of these BBPs among the patients stratified by age, gender, local origin, type of surgery, history of previous transfusion and marital status.

Results

Of the subjects who underwent arthroplasty surgery in our institution, pre-operative screening tests were available for 96.1% (11 609 patients). The seroprevalence of HBV, HCV, HIV and TP was 5.47%, 0.45%, 0.08% and 3.6%, respectively. A total of 761 seropositive cases (68.4%) were previously undiagnosed. Pre-operative screening for HIV resulted in a low cost to benefit ratio, followed by HCV and HBV.

Conclusion

Routine HCV and HIV screening prior to joint arthroplasty is not a cost-effective strategy. Considering the high rate of undiagnosed patients and the shortage of protective options, targeted pre-operative screening for HBV and syphilis should be considered for the protection of healthcare workers in China who have not been vaccinated.

Cite this article: Bone Joint Res 2017;6:566–571.

Understanding consumer and clinician preferences and decision making for rehabilitation following arthroplasty in the private sector

Background

To understand private consumer and clinician preferences towards different rehabilitation modes following knee or hip arthroplasty, and identify factors which influence the chosen rehabilitation pathway.

Methods

Mixed methods cross-sectional study involving 95 semi-structured interviews of consumers (patients and carers) and clinicians (arthroplasty surgeons, physiotherapists and rehabilitation physicians) in Sydney, Australia, during 2014–2015. Participants were asked about the acceptability of different modes of rehabilitation provision, and factors influencing their chosen rehabilitation pathway. Interviews were in person or via the telephone. Qualitative analysis software was used to electronically manage qualitative data. An analytical approach guided data analysis.

Results

Pre-operative preferences strongly influenced the type of rehabilitation chosen by consumers. Key factors that influenced this were both intrinsic and extrinsic, including; the previous experience of self or known others, the perceived benefits of the chosen mode, a sense of entitlement, the role of orthopaedic surgeons and influence of patient preference, a patient’s clinical status post-surgery, the private hospital business model and insurance provider involvement. The acceptability of rehabilitation modes varied between clinician groups.

Conclusions

No one rehabilitation mode provided following arthroplasty is singularly preferred by stakeholders. Factors other than the belief that a particular mode was more effective than another appear to dominate the pathway followed by private arthroplasty consumers, indicating evidence-based policies around rehabilitation provision may have limited appeal in the private sector.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-017-2379-9) contains supplementary material, which is available to authorized users.

The implication of the osteolysis threshold and interfacial gaps on periprosthetic osteolysis in cementless total hip replacement

Osteolysis around joint replacements may develop due to migration of wear particles from the joint space into gaps between the interface bone and the implant where they can accumulate in high concentrations to cause tissue damage. Osteolysis may appear in various postoperative times and morphological shapes which can be generalized into linear and focal. However, there are no clear explanations on the causes of such variations. Patients' degree of sensitivity to polyethylene particles (osteolysis thresholds), the local particle concentration and the access route provided by the interface gaps have been described as determining factors. To study their effects, a 2D computational fluid dynamics model of the hip joint capsule in communication with an interfacial gap and the surrounding bone was employed. Particles were presented using a discrete phase model (DPM). High capsular fluid pressure was considered as the driving force for particle migration. Simulations were run for different osteolysis thresholds ranging from 5×10⁸ to 1×10¹² particle number per gram of tissue and fibrous tissue generation in osteolytic lesion due to particles was simulated for the equivalent of ten postoperative years. In patients less sensitive to polyethylene particles (higher threshold), osteolysis may be linear and occur along an interfacial gap in less than 5% of the interfacial tissue. Focal osteolysis is more likely to develop in patients with higher sensitivity to polyethylene particles at distal regions to an interfacial gaps where up to 80% of the interfacial tissue may be replaced by fibrous tissue. In these patients, signs of osteolysis may also develop earlier (third postoperative year) than those with less sensitivity who may show very minor signs even after ten years. This study shows the importance of patient sensitivity to wear particles, the role of interfacial gaps in relation to morphology and the onset of osteolysis. Consequently, it may explain the clinically observed variation in osteolysis development.

Management of Prosthetic Joint Infection

Although uncommon, prosthetic joint infection is a devastating complication. This challenging condition requires a coordinated management approach to achieve good patient outcomes. This review details the general principles to consider when managing patients with prosthetic joint infection. The different medical/surgical treatment strategies and how to appropriately select a strategy are discussed. The data to support each strategy are presented, along with discussion of antimicrobial strategies in specific situations.

Is there a risk of permanent renal dysfunction after primary total hip and knee joint replacements?

Background

Permanent renal dysfunction is considered as being a serious complication which may occur after major surgery and which furthermore may lead to increased morbidity and mortality. The objective of this study was to analyze the incidence of long-term postoperative renal dysfunction after primary total hip and knee joint replacements.

Methods

Long-term postoperative renal dysfunction was analyzed in a retrospective study of 1301 consecutive primary total hip and knee joint replacements performed between January 2009 and December 2013. According to the RIFLE criteria, increased serum creatinine was an indicative of postoperative renal injury. The highest serum creatinine during the first postoperative week was chosen as a sign for maximum acute renal injury and was compared to the highest serum creatinine during the following 4–12 months.

Results

One hundred and forty two patients with an increase in postoperative serum creatinine were included in the follow-up study. Six patients (4.2 %) died due to non-renal causes during the follow-up period. One patient died of severe renal injury, which was relatively very early postoperatively, and another patient had a rise in serum creatinine to 316 μmol/l during the follow-up period. All the remaining 132 patients (94 %) had full recovery with serum creatinine which returned to preoperative levels.

Conclusions

This study did not confirm that patients who underwent primary total hip and knee joint replacement surgery were at risk of developing permanent renal dysfunction up to 1 year after the index surgery.

Evaluation of three co-morbidity measures to predict mortality in patients undergoing total joint arthroplasty

OBJECTIVE

To evaluate the 90 days and 1 year mortality predictive ability of the RxRisk-V, Charlson, and Elixhauser co-morbidity measures in total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients.

METHOD

A retrospective study of 11,848 THAs and 18,972 TKAs (2001-2002) was conducted. Death within 90 days and 1 year of the surgery were the main endpoints. Co-morbidity measures were calculated using either medication or hospitalisation history. Logistic regression models were employed and discrimination and calibration were assessed. Specifically, models with unweighted and weighted measure scores, models with the specific conditions, and a model combining conditions identified by all measures were assessed.

RESULTS

In THAs, the best performing prediction models included co-morbidities from all three measures (90 days: c = 0.84, P = 0.284, 1 year: c = 0.79, P = 0.158). Individually, the model with Charlson conditions performed best at 90 days mortality (c = 0.80, P = 0.777) and the Charlson and Elixhauser performed similarly at 1 year (both c = 0.77, P > 0.05). In TKAs, the best performing prediction model included co-morbidities from all measures (90 days: c = 0.82, P = 0.349, 1 year: c = 0.78, P = 0.873). Individually, the model with Elixhauser conditions performed best with 90 days mortality (c = 0.79, P = 0.435) and all performed similarly at 1 year (c = 0.74-0.75, all P > 0.05).

CONCLUSIONS

A combined model with co-morbidities identified by the Elixhauser, Charlson, and RxRisk-V was the best mortality prediction model. The RxRisk-V did not perform as well as the others. Because of the Elixhauser and Charlson's similar performance we suggest basing the choice of measurement use on factors such as the need of specific conditions and modelling limitations.