Postoperative recovery after total hip arthroplasty (THA) can lead to the development of prolonged opioid use but there are few tools for predicting this adverse outcome. The purpose of this study is ...to develop machine learning algorithms for preoperative prediction of prolonged opioid prescriptions after THA.
A retrospective review of electronic health records was conducted at 2 academic medical centers and 3 community hospitals to identify adult patients who underwent THA for osteoarthritis between January 1, 2000 and August 1, 2018. Prolonged postoperative opioid prescriptions were defined as continuous opioid prescriptions after surgery to at least 90 days after surgery. Five machine learning algorithms were developed to predict this outcome and were assessed by discrimination, calibration, and decision curve analysis.
Overall, 5507 patients underwent THA, of which 345 (6.3%) had prolonged postoperative opioid prescriptions. The factors determined for prediction of prolonged postoperative opioid prescriptions were age, duration of opioid exposure, preoperative hemoglobin, and preoperative medications (antidepressants, benzodiazepines, nonsteroidal anti-inflammatory drugs, and beta-2-agonists). The elastic-net penalized logistic regression model achieved the best performance across discrimination (c-statistic = 0.77), calibration, and decision curve analysis. This model was incorporated into a digital application able to provide both predictions and explanations (available at https://sorg-apps.shinyapps.io/thaopioid/).
If externally validated in independent populations, the algorithms developed in this study could improve preoperative screening and support for THA patients at high risk for prolonged postoperative opioid prescriptions. Early identification and intervention in high-risk cases may mitigate the long-term adverse consequence of opioid dependence.
III.
Background
Current estimates for the direct costs of a single episode of care for periprosthetic joint infection (PJI) after THA are approximately USD 100,000. These estimates do not account for the ...costs of failed treatments and do not include indirect costs such as lost wages.
Questions/purposes
The goal of this study was to estimate the long-term economic effect to society (direct and indirect costs) of a PJI after THA treated with contemporary standards of care in a hypothetical patient of working age (three scenarios, age 55, 60, and 65 years).
Methods
We created a state-transition Markov model with health states defined by surgical treatment options including irrigation and débridement with modular exchange, single-stage revision, and two-stage revision. Reoperation rates attributable to septic and aseptic failure modes and indirect and direct costs were calculated estimates garnered via multiple systematic reviews of peer-reviewed orthopaedic and infectious disease journals and Medicare reimbursement data. We conducted an analysis over a hypothetical patient’s lifetime from the societal perspective with costs discounted by 3% annually. We conducted sensitivity analysis to delineate the effects of uncertainty attributable to input variables.
Results
The model found a base case cost of USD 390,806 per 65-year-old patient with an infected THA. One-way sensitivity analysis gives a range of USD 389,307 (65-year-old with a 3% reinfection rate) and USD 474,004 (55-year-old with a 12% reinfection rate). Indirect costs such as lost wages make up a considerable portion of the costs and increase considerably as age at the time of infection decreases.
Conclusions
The results of this study show that the overall treatment of a periprosthetic infection after a THA is markedly more expensive to society than previously estimated when accounting for the considerable failure rates of current treatment options and including indirect costs. These overall costs, combined with a large projected increase in THAs and a steady state of septic failures, should be taken into account when considering the total cost of THA. Further research is needed to adequately compare the clinical and economic effectiveness of alternative treatment pathways.
Level of Evidence
Level II, economic and decision analysis.
As cost‐effective measures become increasingly implemented in the US healthcare system, changes in patient‐reported outcome measure (PROM) scores can be utilized to indicate patient satisfaction ...following procedures including total knee arthroplasty (TKA). The primary aim of this study was to develop and evaluate machine learning algorithms to predict achievement of the minimal clinically important difference (MCID) for the Knee Injury and Osteoarthritis Outcome Score‐Physical Function Short Form (KOOS‐PS) at 1‐year following TKA. A retrospective review of primary TKA patients between 2016 and 2018 was performed. Variables considered for prediction included demographics and preoperative PROMs. The KOOS‐PS MCID was calculated via a distribution‐based method. Five machine learning algorithms were developed and tested by discrimination, calibration, Brier score, and decision curve analysis. Among the 744 patients who met the inclusion criteria, 385 (72.8%) patients achieved the MCID. The elastic‐net penalized logistic regression model was selected as the best performing model (c‐statistic 0.77, calibration intercept −0.02, calibration slope 1.15, and Brier score 0.14). The most important variables for MCID achievement were preoperative KOOS‐PS score, preoperative VAS Pain, preoperative opioid use, preoperative PROMIS global mental health score, age, and sex. Algorithms were incorporated into an open‐access digital application available at https://sorg-apps.shinyapps.io/tka_koos_mcid/. This study is the first to predict the probability of achieving the KOOS‐PS MCID following TKA using a machine learning‐based approach. The results were used to develop a clinical decision aid based on commonly collected predictive variables to preoperatively predict an individual patient's likelihood of attaining an acceptable outcome following TKA.
Although morbid obesity is an established risk factor for periprosthetic joint infection following total hip arthroplasty and total knee arthroplasty, little is known regarding the infection control ...rate of this cohort following debridement, antibiotics, and implant retention (DAIR). The purpose of this study is to investigate the infection control rate following DAIR in a morbidly obese patient cohort compared to a nonobese patient cohort and discern the relationship between time from diagnosis to treatment and risk of DAIR failure.
Results of all DAIR procedures were retrospectively reviewed across 4 institutions. Those with a body mass index of at least 40 kg/m2 were matched 2:1 on the basis of patient age, sex, date of surgery, and presence of staphylococcal species in culture to a cohort of patients with body mass index of <30 kg/m2. Demographic variables were collected for each patient. Kaplan-Meier survivorship curves were constructed and multivariable Cox regression was performed for analysis.
The morbidly obese group experienced a higher treatment failure rate (57.9%) compared to the nonobese group (36.8%; P = .035). Morbid obesity and major depressive disorder/generalized anxiety disorder diagnosis significantly increased the risk of failure, with hazard ratios of 1.82 and 2.09, respectively. Morbidly obese patients who received DAIR within 48 hours of symptom presentation did not face an increased risk of reinfection compared to nonobese patients.
Our findings suggest morbidly obese patients face an increased risk of DAIR failure; however, this risk can be mitigated if DAIR is received within 48 hours of symptom onset.
Purpose
To investigate the in vivo femoral condyle motion and synergistic function of the ACL/PCL along the weight-bearing knee flexion.
Methods
Twenty-two healthy human knees were imaged using a ...combined MRI and dual fluoroscopic imaging technique during a single-legged lunge (0°–120°). The medial and lateral femoral condyle translation and rotation (measured using geometric center axis-GCA), and the length changes of the ACL/PCL were analyzed at: low (0°–30°), mid-range (30°–90°) and high (90°–120°) flexion of the knee.
Results
At low flexion (0°–30°), the strains of the ACL and the posterior–medial bundle of the PCL decreased. The medial condyle showed anterior translation and lateral condyle posterior translation, accompanied with a sharp increase in external GCA rotation (internal tibial rotation). As the knee continued flexion in mid-range (30°–90°), both ACL and PCL were slack (with negative strain values). The medial condyle moved anteriorly before 60° of flexion and then posteriorly, accompanied with a slow increase of GCA rotation. As the knee flexed in high flexion (90°–120°), only the PCL had increasingly strains. Both medial and lateral condyles moved posteriorly with a rather constant GCA rotation.
Conclusions
The ACL and PCL were shown to play a reciprocal and synergistic role during knee flexion. Mid-range reciprocal anterior–posterior femoral translation or laxity corresponds to minimal constraints of the ACL and PCL, and may represent a natural motion character of normal knees. The data could be used as a valuable reference when managing the mid-range “instability” and enhancing high flexion capability of the knee after TKAs.
Level of evidence
Level IV.
Background: Several therapeutic agents have been shown to inhibit fibrosis and improve regeneration after injury in skeletal muscle by
antagonizing transforming growth factor-β1. Angiotensin ...receptor blockers have been shown to have a similar effect on transforming
growth factor-β1 in a variety of tissues.
Hypothesis: Systemic treatment of animals after injury of skeletal muscle with an angiotensin receptor blocker may decrease fibrosis
and improve regeneration, mainly through transforming growth factor-β1 blockade, and can be used to improve skeletal muscle
healing after injury.
Study Design: Controlled laboratory study.
Methods: Forty mice underwent bilateral partial gastrocnemius lacerations. Mice were assigned randomly to a control group (tap water),
a low-dose angiotensin receptor blocker group (losartan, 0.05 mg/mL), or a high-dose angiotensin receptor blocker group (0.5
mg/mL). The medication was dissolved in tap water and administered enterally. Mice were sacrificed 3 or 5 weeks after injury,
and the lacerated muscles were examined histologically for muscle regeneration and fibrosis.
Results: Compared with control mice at 3 and 5 weeks, angiotensin receptor blockerâtreated mice exhibited a histologic dose-dependent
improvement in muscle regeneration and a measurable reduction in fibrous tissue formation within the area of injury.
Conclusion: By modulating the response to local and systemic angiotensin II, angiotensin receptor blocker therapy significantly reduced
fibrosis and led to an increase in the number of regenerating myofibers in acutely injured skeletal muscle. The clinical implications
for this application of angiotensin receptor blockers are potentially far-reaching and include not only sports- and military-related
injuries, but also diseases such as the muscular dystrophies and trauma- and surgery-related injury.
Clinical Relevance: Angiotensin receptor blockers may provide a safe, clinically available treatment for improving healing after skeletal muscle
injury.
Keywords:
fibrosis
angiotensin receptor blocker
TGF-β
muscle injury
muscle regeneration
Spines with ankylosis or with a history of lumbosacral fusions have been collectively classified as rigid and unbalanced, and associated with an increased rate of dislocation after total hip ...arthroplasty (THA). It remains unknown whether the cause of spinal arthrodesis influences the dislocation rate.
A retrospective study was conducted from January 2000 to December 2017, with an institutional review board's approval to identify 2 cohorts with a history of THA: one with ankylosing spondylitis (AS) involving the lumbosacral spine and another cohort with a history of lumbosacral spinal fusion (SF). A chart review was performed to collect demographic and surgical variables. Lumbar lordosis angle (LLA), acetabular anteversion, and inclination angle measurements were taken for each patient. Kaplan-Meier survivorship curves were constructed and multivariable Cox regression was performed for analysis.
The AS and SF cohorts consisted of 142 and 135 patients, respectively. The SF group had a greater mean LLA (34.18°) than the AS group (21°). A total of 16 patients (11.85%) suffered from dislocation after primary elective THA in the SF group, whereas 4 patients (2.82%) in the AS group. After multivariable Cox regression analysis, increasing LLA and hips outside of the Lewinnek safe zone were found to be associated with a higher hazard of dislocation after THA.
We found that the degree of lumbar spine curvature is more associated with dislocation after THA than the history of SF itself; specifically, an increase in lumbar lordosis angle of 1º increases the probability of dislocation by 13% among AS and SF patients.
We define the value of the Minimal Clinically Important Difference for Worsening (MCID-W) for Patient-Reported Outcomes Measurement Information System Physical Function short form 10-a ...(PROMIS-PF-10a) score for primary total joint arthroplasty (TJA) of the hip and knee and describe the risk factors for patients scoring worse than the MCID-W.
This retrospective study was performed using 3414 primary TJA patients. PROMIS-PF-10a scores were collected at the preoperatively and postoperatively, and patients were classified based on reaching Minimal Clinically Importance Difference for Improvement (MCID-I), MCID-W, or “no significant change” after TJA (scores betweex`n MCID-W and MCID-I). MCID-W and MCID-I values were determined by a distribution method. The association between numerous variables and scoring worse than the MCID-W of PROMIS-PF-10a was then evaluated through multiple logistic regression. A threshold for preoperative PROMIS-PF-10a score predicting decline past MCID-W was determined using the Youden index and receiver operating characteristic curve.
The MCID-W for TJA was −1.89. Notably, increasing length of stay (odds ratio OR 1.073, 95% confidence interval CI 1.029-1.119, P < .001) and increasing preoperative PROMIS-PF-10a scores (OR 1.117, 95% CI 1.091-1.144, P < .001) were associated with increased likelihood of decline past the MCID-W of the PROMIS-PF-10a for TJA compared with patients who achieved the MCID-I. A community hospital with a dedicated joint replacement center was associated with a decreased risk for decline past the MCID-W (OR 0.601, 95% CI 0.402-0.899; P = .013).
We described the MCID-W value (−1.89) for the PROMIS-PF-10a questionnaire for knee and hip TJA and associated patient- and hospital-level risk factors for failure after TJA. Healthcare funding initiatives should be directed toward modifiable factors associated with clinically significant worse outcomes after TJA.
Utilization of total joint arthroplasty (TJA) by minorities is disproportionately low compared to Whites. Contributing factors include poorer outcomes, lower expectations, and decreased access to ...care. This study aimed to evaluate if race and income were predictive of preoperative patient-reported outcome measures (PROMs) and the likelihood of achieving the minimal clinically important difference (MCID) following TJA.
We retrospectively reviewed 1,371 patients who underwent primary TJA between January 2018 and March 2021 in a single healthcare system. Preoperative and postoperative PROM scores were collected for Patient-Reported Outcomes Measurement Information System (PROMIS) Mental Health, PROMIS Physical Function (PF10a), and either Knee injury and Osteoarthritis Outcome Score (KOOS) or Hip disability and Osteoarthritis Outcome Score (HOOS). Demographic and comorbidity data were included as explanatory variables. Multivariable regression was used to analyze the association between predictive variables and PROM scores.
Mean preoperative PROM scores were lower for non-Whites compared to Whites. Increased median household income was associated with higher preoperative PROM scores. Non-White race was associated with lower PROMIS Mental Health and KOOS, but not PF10a or HOOS scores. Only non-White race was associated with a decreased likelihood of achieving MCID for PF10a. Neither race nor income was predictive of achieving MCID for KOOS and HOOS.
Non-White race/ethnicity and lower income were associated with lower preoperative PROMs prior to primary TJA. Continued research is necessary to identify the causes of this discrepancy and correct this disparity.