Journal of Knee Surgery最新文献

Several studies have demonstrated the importance of patient expectation management following surgery, as this is a crucial factor influencing postoperative outcomes. Informing patients on the likelihood on return to sport (RTS) following a knee arthroplasty is therefore important. This systematic review aimed to compare RTS rates and RTS rates per sport-impact level for primary total knee arthroplasty (TKA), unicompartmental knee arthroplasty (UKA), or patellofemoral knee arthroplasty (PFA). A literature search was conducted in PubMed, Embase, and Cochrane up to June 1, 2024. Studies reporting on RTS rate following TKA, medial UKA, or PFA were included. RTS rates per sport impact level, Tegner-Lysholm, and University of California and Los Angeles (UCLA) activity scores were extracted. Outcomes were compared with meta-analysis using random-effect models. Thirty-eight studies were included for qualitative assessment, of which eight for meta-analysis, comprising 7,634 patients. Meta-analysis demonstrated a significantly greater likelihood for UKA patients (80.7% [18.4-100%]) to RTS than TKA patients (69.0% [4.1-100%]; odds ratio: 1.87 [1.23-2.85], p = 0.004). In high-impact sports, UKA patients (65.4% [18.4-100%]) were able to RTS at a higher rate than TKA patients (TKA 4.4% [4.1-12.5%]). RTS to low- and moderate-impact sports were similar. Postoperative UCLA activity score was superior for UKA patients and postoperative Tegner scores between UKA and TKA were similar. PFA patients returned to sports at a low rate (low-impact 42.4% [41.2-43.5%]; moderate-impact 35.0% [34.8-41.2%]; high-impact 20.5% [17.4-35.3%]). UKA Patients had a significantly higher overall RTS rate than TKA patients. Over 50% of UKA patients were able to return to high-impact sports, whereas only 5% of TKA patients achieved this outcome. The likelihood of RTS appeared lowest among patients who underwent PFA. A more liberal counseling regarding return to high-impact sports following UKA may be justified.

There is a high incidence of anterior cruciate ligament (ACL) tears in National Football League (NFL) players. There is a relative paucity of long-term data characterizing the effects of artificial versus natural playing surfaces on ACL tear incidence. A comprehensive search of publicly available data identified any NFL player who sustained an ACL injury from 2012 to 2022. The publicly available databases allowed for characterization of playing surface, player position, timing of injury in season, mechanism of injury, and player's age. Incidence of ACL injuries by playing surface, player position, and position group relative to all other positions or position groups were compared by chi-squared test. Correlates of in-game ACL injury were determined by stepwise multivariate logistic regression. There were 520 NFL players who experienced an ACL tear between seasons 2012-2013 and 2022-2023. There was no significant difference in incidence of ACL tears on artificial turf versus natural playing surfaces (265 versus 255, p = 0.670). Wide receivers (p = 0.027) were associated with a significantly higher incidence of ACL tears compared with other positions. Receivers (wide receivers and tight ends) (p = 0.007) were associated with significantly higher incidence of ACL tears compared with other position groups, while specialists (punters, kickers, and long snappers) (p < 0.001) were associated with significantly lower incidence of ACL tears compared with other position groups. No significant difference between mechanism of injury between playing surfaces was found (p = 0.765). More ACL tears occurred before week 9 than on or after week 9 in-season, and the proportion of ACL tears occurring during a game (67%) was significantly higher than those occurring during practice. There was no statistically significant difference in incidence of ACL tears in NFL players from the 2012-2013 to 2022-2023 seasons based on playing surface (artificial versus natural). Wide receivers had a significantly higher incidence of ACL tears compared with other positions and tears were more common during games and before week 9 in-season.

Anterior tibial subluxation (ATS) in knee extension is observed in knees with anterior cruciate ligament (ACL) injuries. Preoperative ATS adversely affects the postoperative anterior stability and increases the risk of early graft failure. To investigate the factors associated with preoperative ATS in knees with ACL injury. A total of 191 patients who underwent primary ACL reconstruction between 2017 and 2022 were included. Preoperatively, all patients underwent lateral radiography with full extension of both knees to evaluate the ATS. These 191 patients were divided into two groups based on ATS positivity. Positive ATS was defined as a side-to-side difference (SSD) in ATS > SD from the average SSD in ATS. The evaluation items included age, sex, height, weight, time from injury to surgery, mechanism of injury, posterior tibial slope, knee hyperextension angle, anterior tibial translation (ATT), meniscal tear on arthroscopy, and intraoperative pivot shift grade. There were 32 patients in the ATS-positive group. The overall average SSD in ATS was 1.7 ± 1.9 mm. Therefore, ATS > 3.6 mm was regarded as positive ATS. A logistic regression analysis indicated that positive ATS predictors were the ATT (odds ratio [OR]: 1.27; 95% confidence interval [CI]: 1.13-1.44; p < 0.001), >6 months from injury to surgery (OR: 2.89; 95% CI: 1.19-7.06; p = 0.02), and the contralateral hyper-extension angle (OR: 1.10; 95% CI: 1.00-1.21; p = 0.049). No significant difference was observed between the groups regarding meniscal tears. Anterior knee laxity, chronicity of ACL-deficiency, and hyperextension affect preoperative ATS in knees with ACL injuries. This study is a cross-sectional study providing level III evidence.

Cobalt-chromium-molybdenum (Co-Cr-Mo) femoral components are widely used in total knee arthroplasty (TKA) due to their mechanical strength and wear performance. However, concerns regarding corrosion, metal ion release, and hypersensitivity have prompted the development of alternative materials, including nitrided titanium-aluminum-vanadium (nTi-6Al-4V). This study aimed to compare the simulated wear performance of Co-Cr-Mo and nTi-6Al-4V femoral components when articulated against conventional polyethylene articular surface bearings and evaluate the fatigue performance of nTi-6Al-4V components. In vitro wear testing, per ISO 14243-3, was conducted for 5 million cycles (Mc) using posterior-stabilized Persona Primary knee system femoral components manufactured from Co-Cr-Mo and nTi-6Al-4V coupled with conventional ultra-high-molecular-weight polyethylene articular surfaces. Mean steady-state wear rates (mg/Mc) of the articular surface bearings were gravimetrically determined. Surface roughness (Ra) measurements of the femoral components and the articulating surfaces were captured using a contacting stylus profilometer. Polyethylene wear debris morphology was also analyzed. Two fatigue loading scenarios (cantilever loading and three-point bend) of the posterior condyles of femoral components were completed for 10 Mc. The mean steady-state wear rate of the nTi-6Al-4V bearing couple (17.0 ± 1.8 mg/Mc) was noninferior to the Co-Cr-Mo bearing couple (22.8 ± 6.7 mg/Mc). No statistically significant differences were found in the Ra measurements of femoral components or articular surfaces before and after 5.0 Mc (p = 0.21). No statistical difference in polyethylene debris morphology was observed between components (p = 0.07). In both fatigue loading scenarios, no fracture or cracking of the nTi-6Al-4V femoral components occurred. The Co-Cr-Mo and nTi-6Al-4V bearing couples performed similarly regarding mean steady-state wear rates, Ra measurements, and debris morphology in simulated wear conditions. These results provide insights into the wear properties of Co-Cr free femoral TKA components. Additionally, the nTi-6Al-4V components met the performance requirements related to posterior condyle fatigue strength. Further clinical studies are needed to confirm these in vitro findings.

Novel implant systems have design modifications that seek to improve total knee arthroplasty (TKA) survivorship. We evaluated overall and cause-specific revision risk for a newer generation implant system compared with its predecessor from the same manufacturer. We conducted a cohort study using data from the United States-based Kaiser Permanente Total Joint Replacement Registry. Adult patients who underwent primary, fully cemented, fixed-bearing TKA for osteoarthritis between 2009 and 2022 were identified. Only two implant systems from the manufacturer were included: the newer generation (n = 22,287) and the older generation (n = 37,105). Multivariable Cox regression was used to evaluate overall and cause-specific aseptic revision risk. In the adjusted analyses, no difference in risk was observed for the newer compared with older generation system in the first 4-year follow-up (hazard ratio [HR] = 0.94, 95% confidence interval [CI] = 0.74-1.19); however, a higher risk was observed after 4-year follow-up (HR = 2.09, 95% CI = 1.41-3.08). This higher risk was due to loosening (within 4 years: HR = 0.90, 95% CI = 0.59-1.37; after 4 years: HR = 2.88, 95% CI = 1.84-4.51); no differences were observed for other revision reasons. When considering constructs utilizing different trays of the newer generation system, the higher risk of revision for loosening was observed only when the first iteration of the tray was used (HR = 1.94, 95% CI = 1.37-2.77); no difference was observed for constructs utilizing the subsequent iterations of the tray, which underwent design changes, when compared with the older generation TKA system (HR = 0.45, 95% CI = 0.20-1.01). We found no survivorship advantage with a newer TKA design compared with a preceding design from the same manufacturer. The higher risk of revision for loosening in the newer generation constructs was limited to those utilizing the first tray iteration, which is now discontinued by the manufacturer. The higher revision risk was not observed with subsequent iterations of the newer generation construct relative to the older generation. LEVEL OF EVIDENCE:  Level III.

Renal osteodystrophy (ROD), a skeletal complication of chronic kidney disease (CKD)-mineral and bone disorder, may influence perioperative outcomes after total knee arthroplasty (TKA), but its impact remains unclear. This study examined patient characteristics, hospital resource utilization, and postoperative complications in ROD patients undergoing primary TKA. We performed a retrospective cohort analysis of the National Inpatient Sample (2010-2019). Adults undergoing primary TKA were identified and stratified by ROD status. Propensity score matching (PSM; 1:20) was used to balance age, sex, race, comorbidities, and CKD stage. Outcomes included length of stay (LOS), hospital charges, and medical and surgical complications. Among 1,196,522 TKA patients, 283 (0.02%) had ROD. After matching (n = 5,337 controls), ROD patients had a longer median LOS (3 vs. 3 days; p < 0.001) and markedly higher median hospital charges ($58,550 vs. $18,004; p < 0.001). ROD was associated with increased odds of medical complications, including thrombocytopenia (OR: 3.2; 95% CI: 1.9-5.2), convulsion (OR: 6.9; 2.5-19.6), heart failure (OR: 2.3; 1.5-3.4), chest pain (OR: 3.4; 1.2-10.0), acute cerebrovascular disease (OR: 3.0; 1.4-6.4), stroke (OR: 3.3; 1.6-6.8), pneumonia (OR: 3.9; 1.7-9.0), and acute renal failure (OR: 2.3; 1.6-3.5). Surgical risks were also elevated, notably periprosthetic fracture (OR: 7.1; 2.2-22.9), joint dislocation (OR: 4.6; 1.7-12.3), and lower limb peripheral nerve injury (OR: 2.5; 1.4-4.7). ROD patients undergoing primary TKA incur greater hospital resource use and substantially higher rates of diverse medical and surgical complications. These findings highlight ROD as an independent risk factor warranting targeted preoperative risk stratification, multidisciplinary perioperative planning, and bone health optimization to improve outcomes and resource efficiency in this high-risk population.The level of evidence is 3.Trial registration is not applicable.

Despite urgent operative management of septic knee arthritis with irrigation and debridement and culture-specific antibiotic therapy, the incidence of additional washouts in knee septic arthritis has been noted to be between 11.4 and 40%. The purpose of this study was to analyze preoperative and postoperative variables associated with failure of primary washout in septic knees. A retrospective review was conducted at a Level I trauma center for all patients with septic arthritis who underwent open irrigation and debridement from 2010 to 2023. Patients were excluded if they were noted to have a knee arthroplasty or additional infection source aside from bacteremia. Demographic information, comorbidities, dates of operative washouts, vitals, and inflammatory markers were noted. Ninety-seven patients met inclusion and exclusion criteria. Forty-two required an additional washout. The average number of days between the primary and secondary washouts was 4.9 days. Decreased age (p = 0.03) and primary Staphylococcus aureus culture (p < 0.01) were found to be significantly associated with failure of the primary washout. Preoperative vitals, inflammatory markers, age, body mass index, intravenous drug use, diabetes, and smoking were not found to be predictors of repeat septic knee washouts. Additional subgroup analysis on bacteremic patients and on C-reactive protein (CRP) trends postoperative day 1 and 2 found no significant predictors of single or repeat septic knee washout. Younger age and presence of S. aureus in aspiration cultures were significantly associated with failure of primary washout. Trending CRP in the immediate postoperative period is not an accurate predictor of repeat septic knee washout.

Arthrofibrosis is a common complication following total knee arthroplasty (TKA), characterized by excessive fibrous tissue formation within the joint, leading to restricted range of motion, pain, and functional limitations. This review focuses on three key areas: (1) dysregulated wound healing processes and molecular risk factors; (2) histopathological and immunohistochemical features; and (3) emerging molecular targets and potential personalized treatment strategies. Dysregulated wound healing after TKA leads to persistent fibroblast and myofibroblast activation, excessive extracellular matrix deposition, and joint capsule contracture. Key molecular mediators, such as transforming growth factor-β 1 (TGF-β1), xylosyltransferase-I (XT-I), and β-catenin (β-catenin), drive these processes, exacerbating fibrosis. Genetic predisposition, inflammatory signaling, and immune cell infiltration further contribute to the progression of arthrofibrosis. Histopathologically, arthrofibrotic tissue shows increased collagen types I and III deposition, along with upregulated markers such as α-smooth muscle actin and TGF-β1 receptor 1, reflecting myofibroblast activation and inflammation. Immunohistochemical analysis reveals abundant CD68+ macrophages and T cell infiltration, supporting the inflammatory microenvironment. Recent advances in molecular profiling have identified potential biomarkers and therapeutic targets, including bromodomain-containing protein 4 and XT-I, offering hope for personalized medicine. Despite promising preclinical findings, clinical translation remains in its early stages. Future research should prioritize the validation of these biomarkers and explore genetic and epigenetic stratification to improve management and outcomes for high-risk patients.

Arthrofibrosis is a debilitating complication following total knee arthroplasty (TKA), resulting in limited knee range of motion (ROM) and functional impairment. This review explores the (1) epidemiology, (2) risk factors, and (3) prevention strategies associated with arthrofibrosis. The incidence of arthrofibrosis ranges from 3 to 10% in primary TKA cases, with up to 13% in some series, and it contributes to up to 10% of revision surgeries within 5 years. Genetic and molecular factors may play a role in predisposition. Other risk factors include younger age, preoperative limited ROM, and surgical factors like prosthetic malpositioning. Prevention strategies focus on patient education, rehabilitation, and pharmacological interventions, with emerging evidence supporting the use of celecoxib, dexamethasone, COX-2 inhibitors, and losartan in reducing the risk of arthrofibrosis. Despite progress, gaps remain, particularly regarding standardized definitions and high-quality randomized controlled trials to assess the optimal treatment methods.

Value in health care is defined as optimized patient-centered outcomes and streamlined costs of care. A patient-level value analysis (PLVA) is a novel value-based health care research method. In a PLVA, the ratio of outcomes to cost is calculated for each individual patient in a cohort, and factors that optimize value are investigated. We performed a PLVA in primary total knee arthroplasty (TKA). We conducted a retrospective analysis of a prospectively maintained multi-institutional arthroplasty registry. A total of 2,789 primary manual TKAs were analyzed. Knee Osteoarthritis Outcome Score-Physical Function Short-Form (KOOS-PS) scores and costs of care using time-driven activity-based costing (TDABC) were collected. All costs were converted from U.S. dollars to arbitrary cost units (CUs) to protect confidential hospital financial data. The primary outcome was the value quotient (Value _KOOS-PS), or the ratio of 1-year improvement in KOOS-PS to the cost of care, which was converted to a scale with a maximum of 100. Multivariable forward linear regression determined factors impacting value in primary TKA. The mean improvement in KOOS-PS was 15.2. The mean cost of care was 859 CUs. The largest contributors to cost were the implant cost (378 CUs, 44.0%) and intraoperative personnel cost (173 CUs, 20.1%). Patient and hospital factors independently correlated with improved TKA Value _KOOS-PS included home discharge (adjusted mean difference: +7.8; p < 0.001), outpatient surgery (adjusted mean difference: +3.6; p < 0.001), lower preoperative KOOS-PS score (adjusted mean difference: +0.6; p < 0.001), lower Charlson Comorbidity Index (adjusted mean difference: +0.6; p = 0.006), and lower body mass index (BMI; adjusted mean difference: +0.2; p = 0.001). Using TDABC and patient-reported outcome measures, we performed a PLVA. We found that the largest contributor to the cost of care was the implant cost. The highest value TKAs occurred in an outpatient setting with home discharges, for patients with more severe preoperative knee symptoms, fewer comorbidities, and lower BMI. Surgeons and hospital administrators can use these findings to inform strategies to optimize value in TKA.