Journal of Knee Surgery最新文献

Although several prior studies have described the outcomes of osteochondral allograft (OCA) transplantation for single osteochondral lesions, there is a paucity of comparative data on outcomes of single versus multiple OCA transplants. We aimed to describe the initial outcomes of single-plug versus multiple-plug knee OCA transplants at a minimum of 1 year of follow-up. We hypothesized that there would be no difference in patient-reported outcome measures (PROMs) between patients undergoing single-plug and multiple-plug OCA transplants at a minimum of 1 year of follow-up. We retrospectively reviewed the prospectively collected data of patients undergoing OCA transplantation for large (>2 cm²) osteochondral defects of the knee. Thirty patients who underwent multiple-plug (2 + ) OCA transplants (either single surface using the snowman technique or multi-surface) were 1:1 age, sex, and body mass index (BMI) matched with 30 patients who underwent single-plug OCA transplants. PROMs, including the International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscores, were obtained both preoperatively and at a minimum of 1 year postoperatively. Failure was defined as a revision OCA or conversion to unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA). The cohort comprised 30 females (31 affected left knees), with an average age of 37 ± 10.3 years and median follow-up of 2.0 years (interquartile range: 1.7-2.5 years). There was a significant increase in PROMs from the preoperative to the postoperative period for the entire cohort and the single-plug versus multiple-plug subgroups (p < 0.01). There was no difference between the groups with respect to the percentage of patients who achieved the minimal clinically important difference (MCID) for each PROM (p > 0.05). There were two failures, both in the single-plug group, with a mean time to failure of 3.5 years. There was no difference in the initial outcomes between patients undergoing single-plug versus multiple-plug OCA transplant at the short-term follow-up. LEVEL OF EVIDENCE::  Level IV, case series.

Outpatient total knee arthroplasty (TKA) is being performed more frequently in ambulatory surgical centers (ASCs) to decrease the cost of care. Discharge pathways include 23-hour observation (OBSERVATION) or same-day discharge home (HOME), which differ in postoperative medical supervision. Few studies allow patients to self-select their discharge pathway. This study compared patient variables between self-selected OBSERVATION or HOME discharge after TKA at an ASC. We hypothesized that age, sex, and distance lived from the ASC would differ between discharge pathways. Clinical and patient-reported outcomes were explored.A chart review identified 130 patients with TKA at an ASC between November 2017 and December 2019. Patients self-selected OBSERVATION or HOME during a preoperative physician visit. Patient variables obtained from the electronic medical record were age, sex, race/ethnicity, marital status, body mass index, diabetic status, American Society of Anesthesiologists (ASA) class, distance lived from the ASC, anesthesia type, procedure time, and time in the postanesthesia recovery unit. Clinical outcomes (knee range of motion, infection rate, and reoperation rate) and patient-reported outcomes (Knee Injury and Osteoarthritis Outcome Score, Joint Replacement [KOOS, JR]; Oxford Knee Score [OKS]) were collected at either 6 or 12 weeks postsurgery. Variables were compared between groups.Pathway selection was n = 70 OBSERVATION and n = 60 HOME, and all patients completed their self-selected discharge pathway. Age and proportion of females were significantly higher in OBSERVATION than in HOME (61.3 ± 3.5 vs. 58.5 ± 5.4 years, 85.7 vs. 65.0%, respectively; p < 0.05). Distance lived from the ASC tended to be greater in OBSERVATION than HOME (22.1 ± 24.6 vs. 15.3 ± 10.1 miles, p = 0.056). Across groups, clinical outcomes were favorable (i.e., >88% met the 6-week knee flexion milestone, 1.9% infection rate, and 3.1% manipulation under anesthesia), and the preoperative to 12-week postoperative change in KOOS, JR and OKS scores met the minimal clinically important difference.Older age, female sex, and farther distance lived from the ASC may influence patients to select OBSERVATION over HOME discharge following TKA at an ASC. No robust differences were found in early outcomes.

A critical and difficult aspect of total knee arthroplasty (TKA) is ligamentous balancing for which cadavers and models have played a large role in the education and training of new arthroplasty surgeons, although they both have several shortcomings including cost, scarcity, and dissimilarity to in vivo ligament properties. An advanced knee simulator (AKS) model based on computed tomography (CT) scans was developed in the setting of these challenges with cadavers and previous models. In this study, we compared the ligament balancing between AKS and human cadaveric knees to assess the validity of using the AKS for ligament balancing training during TKA. A CT scan of a TKA patient with varus deformity was used to design the AKS model with modular components, using three-dimensional printing. Three fellowship-trained arthroplasty surgeons used technology-assisted TKA procedure to plan and balance three cadaver knees and the AKS model. Medial and lateral laxity data were captured using manual varus and valgus stress assessments for cadavers and the model in an extension pose (10 degrees of flexion from terminal extension) and between 90 and 95 degrees for flexion. After preresection assessments, surgeons planned a balanced cruciate-retaining TKA. Following bony cuts and trialing, extension and flexion ligament laxity values were recorded in a similar manner. Descriptive statistics and Student's t-tests were performed to compare the cadavers and model with a p-value set at 0.05. Preresection medial/lateral laxity data for both extension and flexion were plotted and showed that the highest standard deviation (SD) for the cadavers was 0.67 mm, whereas the highest SD for the AKS was 1.25 mm. A similar plot for trialing demonstrated that the highest SD for the cadavers was 0.6 mm, whereas the highest SD for the AKS was 0.61 mm. The AKS trialing data were highly reproducible when compared with cadaveric data, demonstrating the value of the AKS model as a tool to teach ligament balancing for TKA and for future research endeavors.

A substantial proportion of Hong Kong's aging population suffers from osteoarthritis in both knees. Bilateral total knee arthroplasty (BTKA) is a surgical option for addressing this condition and can be performed via two approaches: simultaneous BTKA (SimBTKA) and staged BTKA (StaBTKA). We compared the cost-effectiveness and safety of these two methods in our institution. We retrospectively reviewed 2,372 patients (SimBTKA, 772; StaBTKA, 1,600; females, 1,780; males, 592; mean age at SimBTKA, 70.4 ± 7.99 years; mean age at StaBTKA, 66.4 ± 7.50 years; p < 0.001) who underwent BTKA in our institution from 2001 to 2022. Patients were categorized according to the surgical approach. Patients undergoing BTKA in our institution were included. Particularly for SimBTKA, patients were assessed by anesthetists to be medically fit before undergoing the procedure according to their age, American Society of Anesthesiologists status, and osteoarthritis severity. The primary outcome was the length of stay (LOS) after surgery. The secondary outcomes were the 30-day unintended readmission, intensive care unit (ICU) admission, and death. SimBTKA had a shorter mean total LOS (acute hospital + rehabilitation center; SimBTKA, 13.09 days; StaBTKA, 18.12 days; p < 0.001) and mean LOS in acute hospital (SimBTKA, 7.70 days; StaBTKA, 10.42 days; p < 0.001). However, no significant difference was found in the mean LOS in rehabilitation centers (SimBTKA, 5.47 days; StaBTKA, 6.32 days; p > 0.05) between the two approaches. The 30-day unintended readmission rate was lower in SimBTKA (SimBTKA, 2.07%; StaBTKA, 3.30%; odds ratio [OR] = 1.60; p > 0.05) but statistically insignificant. SimBTKA was less costly than StaBTKA by US$ 8,422.22 per patient. No significant differences in ICU admission and death rates were found (p > 0.05) between the two groups. SimBTKA had a shorter LOS and lower cost than StaBTKA and comparable complication rates. Therefore, SimBTKA should be indicated in medically stable patients.

The aim of this study was to investigate the biomechanical effects of stem extension with a medial tibial bone defect in primary total knee arthroplasty (TKA) on load distribution and stress in the proximal tibia using finite element (FE) analysis.FE simulations were performed on the tibia bone to evaluate the stress and strain on the tibia bone and bone cement. This was done to investigate the stress shielding effect, stability of the tibia plate, and the biomechanical effects in TKA models with various medial defects and different stem length models.The results demonstrated that in the bone defect model, the longer the stem, the lower the average von Mises stress on the cortical and trabecular bones. In particular, as the bone defect increased, the average von Mises stress on cortical and trabecular bones increased. The average increase in stress according to the size of the bone defect was smaller in the long stem than in the short stem. The maximal principal strain on the trabecular bone occurred mainly at the contact point on the distal end of the stem of the tibial implant. When a short stem was applied, the maximal principal strain on the trabecular bone was approximately 8% and 20% smaller than when a long stem was applied or when no stem was applied, respectively.The findings suggest that a short stem extension of the tibial component could help achieve excellent biomechanical results when performing TKA with a medial tibial bone defect.

Mechanical loosening is a leading cause of failure of total knee arthroplasties (TKAs) for which obesity may be a risk factor. With rising rates of obesity and increasing incidence of TKA, the identification of factors to mitigate this cause of failure is necessary. The purpose of this study is to determine if the use of a tibial stem extender (TSE) decreases the risk of mechanical loosening in patients with obesity undergoing TKA. The American Joint Replacement Registry and linked Centers for Medicare & Medicaid Services claims database were utilized to identify a patient cohort with a body mass index (BMI) of 30 kg/m² or greater and age 65 years or older who underwent primary elective TKA between 2012 and 2021. Patients were divided into cohorts based on obesity class and TSE utilization. The estimated association of TSE use, BMI categories, and covariates with the risk of revisions for mechanical loosening in both unadjusted and adjusted settings was determined. Hazard ratios and their 95% confidence intervals for the risk of mechanical loosening were calculated. A total of 258,775 TKA cases were identified. A total of 538 of 257,194 (0.21%) patients who did not receive a TSE and one patient out of 1,581 (0.06%) with a TSE were revised for mechanical loosening. In adjusted analysis, TSE use was not protective against mechanical loosening and BMI > 40 was not a significant risk factor. Use of a TSE was not found to be protective against mechanical loosening in patients with obesity; however, analysis was limited by the small number of outcome events in the cohort. Further analysis with a larger cohort of patients with TSE and a longer follow-up time is necessary to corroborate this finding.

The necessity of immediate postoperative radiographs following total knee arthroplasty (TKA) has long been debated. With the increasing use of robotic-assisted TKA (RTKA), and thus more precise implant placement, the need for immediate postoperative radiographs to determine implant positioning may be unnecessary. We sought to evaluate implant position on the immediate postoperative radiographs following RTKA to determine their necessity. A retrospective review of 150 RTKAs was performed. The posterior slopes for all TKAs were recorded based on the preoperative three-dimensional template. Additionally, two independent trained researchers (J.G./L.B.) each measured the posterior slope of the postoperative day 0 (POD0) radiograph and postoperative week 2 radiograph. The difference in posterior slope measurement between template and POD0, between template and postoperative week 2, and between POD0 and postoperative week 2 was calculated. Of the 150 TKAs performed, there were no periprosthetic fractures found on the POD0 radiograph. The mean difference between the templated posterior slope and measured posterior slope on POD0 was 0.04 degrees (standard deviation [SD], 1.01; p = 0.615). There was a weak correlation between the two values (rs [95% confidence interval (CI)], 0.38 [0.21, 0.53]). When comparing the template to the postoperative week 2 radiographs, there was a mean difference of 0.02 degrees (SD, 0.48; p = 0.556).  However, a moderate to strong correlation was noted (rs [95% CI], 0.71 [0.61, 0.79]). Comparison of the mean posterior slope from POD0 radiograph to that of postoperative week 2 radiograph showed a mean difference of 0.06 degrees (SD, 1.0; p = 0.427). A weak correlation was found between these two values (rs [95% CI], 0.43 [0.26, 0.56]). Given the accuracy and precision of RTKA, along with the ability to decrease cost and radiation, immediate postoperative radiograph may be unnecessary, when pertaining to the uncomplicated RTKA. However, if there is concern for intraoperative fracture, long stems placed in a revision arthroplasty, or other intraoperative complications, then postoperative radiographs are encouraged.

Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) is a severe complication causing a significant burden. The study aims were to establish the epidemiology of microorganisms in TKA PJI, the rate of persistent infection requiring further surgery, and the risk factors for this. Microbiological specimens between June 2002 and March 2017 at five regional hospital sites were identified with revision TKA procedures in the National Joint Replacement Registry. The time between procedures, type of revision strategy, and any subsequent further revision operations were collected. At minimum 2-year follow-up, 174 revision TKA were identified, with a mean patient age of 69 ± 11 years. A broad range of pathogens were identified. Fifty cases (29%) had persistent infection requiring at least one further operative procedure, 13 cases required 3 or more. Coagulase-negative Staphylococcus species (CNS) was seen most with failed surgery, polymicrobial infections also posing a significant risk factor. The best chance of a successful PJI surgical strategy was < 12 months from primary TKA, with the greatest risk between 3 and 5 years (p < 0.05). Younger age significantly increased the risk of further surgery (p < 0.05). Management varied; 103 (59%) debridement, antibiotic therapy and implant retention, with further surgery in 29%; 45 (17%) single-stage revision, with further surgery in 13%; and 26 (15%) two-stage revision, with further surgery in 12%. This study presents the most common causative pathogens for PJI in TKA, and the high rate of persistent infection after initial revision surgery. Risk factors for persistent infection and further revision surgery were polymicrobial and CNS infections, patients who presented between 3 and 5 years following primary TKA, and younger age. This study therefore raises important risk factors and areas for future research to reduce the burden of multiple operations after PJI.

Robotic-assisted total knee arthroplasty (TKA) has been developed to improve functional outcomes after TKA by increasing surgical precision of bone cuts and soft tissue balancing, thereby reducing outliers. The DePuy Synthes VELYS robotic-assisted solution (VRAS) is one of the latest entrants in the robotic TKA market. Currently, there is limited evidence investigating early patient and economic outcomes associated with the use of VRAS. The Premier Healthcare Database was analyzed to identify patients undergoing manual TKA with any implant system compared with a cohort of robotic-assisted TKAs using VRAS between September 1, 2021 and February 28, 2023. The primary outcome was all-cause and knee-related all-setting revisits within 90-day post-TKA. Secondary outcomes included number of inpatient revisits (readmission), operating room time, discharge status, and hospital costs. Baseline covariate differences between the two cohorts were balanced using fine stratification methodology and analyzed using generalized linear models. The cohorts included 866 VRAS and 128,643 manual TKAs that had 90-day follow-up data. The rates of both all-cause and knee-related all-setting follow-up visits (revisits) were significantly lower in the VRAS TKA cohort compared with the manual TKA cohort (13.86 vs. 17.19%; mean difference [MD]: -3.34 [95% confidence interval: -5.65 to -1.03] and 2.66 vs. 4.81%; MD: -2.15 [-3.23 to -1.08], respectively, p-value < 0.01) at 90-day follow-up. The incidence of knee-related inpatient readmission was also significantly lower (53%) for VRAS compared with manual TKA. There was no significant difference between total cost of care at 90-day follow-up between VRAS and manual TKA cases. On average, the operating room time was higher for VRAS compared with manual TKA (138 vs. 134 minutes). In addition, the discharge status and revision rates were similar between the cohorts. The use of VRAS for TKA is associated with lower follow-up visits and knee-related readmission rates in the first 90-day postoperatively. The total hospital cost was similar for both VRAS and manual TKA cohort while not accounting for the purchase of the robot.

Knee extension range of motion (ROM) measurement is important in patients with anterior cruciate ligament (ACL) injury. The main objective is to evaluate the reliability and the minimal detectable change (MDC) of three methods of measuring knee extension ROM in ACL patients. The three common goniometric devices were a universal goniometer, an inclinometer, and a smartphone app. During a single-visit, knee extension ROM was measured in both knees of 92 ACL-injured or -reconstructed patients by two testers blinded to the other's measures. Intrarater, interrater, and test-retest intraclass correlation coefficients (ICC_2,1) were calculated. Intrarater ICC_2,1 was excellent for the three devices ranging from 0.92 to 0.94, with the inclinometer yielding the best results (ICC_2,1 = 0.94 [95% confidence interval, CI: 0.91-0.96]). Interrater ICC_2,1, however, varied from 0.36 to 0.80. The inclinometer and the smartphone app yielded similar results 0.80 (95% CI: 0.71-0.86) and 0.79 (95% CI: 0.70-0.86), respectively, whereas the universal goniometer was 0.36 (95% CI: 0.17-0.53). Test-retest ICC_2,1 for the inclinometer was 0.89 (95% CI: 0.84-0.93), 0.86 (95% CI: 0.79-0.91) for the app, and 0.83 (95% CI:0.74-0.89) for the goniometer. The intrarater, interrater, and test-retest MDC₉₅ values ranged from 2.0 to 3.5, 3.7 to 10.4, and 2.6 to 5.4 degrees, respectively. The goniometer was the least reliable. The inclinometer is the recommended device due to its highest ICC scores among the three devices and ease of use.