Journal of Knee Surgery最新文献

This study investigated isokinetic muscle strength deficits in patients with advanced knee osteoarthritis (KOA) scheduled for total knee arthroplasty (TKA) to explore the relationship between objective strength measures and subjective symptoms such as pain and functional limitations. By analyzing muscle function using isokinetic dynamometry, the study aimed to provide insights into how strength deficits relate to patient-reported outcomes and whether these assessments could inform surgical decision-making. A total of 52 patients (mean age: 66.96 years, 53.85% female) with advanced KOA awaiting TKA were included. Isokinetic muscle strength of the knee, measured in peak torque (Newton-meters), work (Joules), and power (Watts), was assessed bilaterally before surgery using a Biodex dynamometer at angular velocities of 180 degrees/s and 60 degrees/s. Subjective symptoms were evaluated using standardized assessments, including the Numeric Rating Scale (NRS), Knee Injury and Osteoarthritis Outcome Score (KOOS), Short Form-12 (SF-12), Hospital Anxiety and Depression Scale (HADS-D), and EuroQol 5-Dimension 3-Level questionnaire. Findings revealed a significant strength deficit on the affected side scheduled for surgery (p < 0.050). However, correlations between isokinetic knee parameters and symptom scores were weak (|r| ≤0.5), suggesting that subjective complaints do not necessarily align with objective strength measurements. Notably, isokinetic parameters were significantly intercorrelated (p < 0.050). These results indicate that isokinetic dynamometry effectively quantifies muscle strength differences in KOA patients, yet its findings should be considered alongside clinical assessments and patient-reported symptoms to form a comprehensive evaluation of disease severity and surgical necessity.

Patellar instability following total knee arthroplasty (TKA) is a rare, yet serious complication, potentially requiring revision surgery or resulting in chronic dysfunction. When encountered, it is paramount to understand the etiologies, diagnostic approaches, treatment options, and outcomes of the selected treatment. The most common cause of patella instability is improper positioning of components, leading to lateral maltracking of the patella. Factors such as internal rotation and/or medialization of femoral or tibial components and lateralization of the patellar button have been identified as factors that contribute to instability. Additionally, a longstanding valgus deformity of the knee may exacerbate patella maltracking. Patients typically present with anterior knee pain, worsened by activities like stair climbing, and may report sensations of giving way. Radiographs and computed tomography scans aid in evaluating component positioning and rotation. Operative intervention is often necessary, with options ranging from soft tissue realignment to component revision. Lateral retinacular release is a common approach, although it is associated with complications such as osteonecrosis of the patella. Proximal or distal realignment procedures may be required if instability persists. Some recent case reports have also described medial patellofemoral ligament reconstruction as a treatment modality, but more investigation on the topic is still pending. It is important that the treatment strategy address the underlying cause, as failure to do so may result in recurrent instability. The best way to avoid patella instability is to pay attention to all the details of component position and soft tissue balance during the index procedure.

It is still controversial whether anteroposterior laxity or posterior tibial slope (PTS) after total knee arthroplasty (TKA) affects maximum flexion angle. The purpose of this study was to evaluate the relationship between PTS and tibial anteroposterior laxity after TKA and to examine the effect of these factors on knee flexion angle after TKA. This study enrolled 96 knees in 80 patients undergoing cruciate-retaining TKA (CR-TKA). Anterior translation (AT) and posterior translation (PT) were measured separately at a flexion of 90 degrees using stress radiographs. Total anteroposterior translation (APT) was defined as the sum of AT and PT. PTS was measured in a lateral view. In univariate analysis, postoperative flexion angle was positively correlated with preoperative flexion (R = 0.51; p < 0.01), PT (R = 0.48; p < 0.01), and APT (R = 0.48; p < 0.01), whereas it was negatively correlated with body mass index (BMI; R = - 0.43; p < 0.01) and PTS (R = - 0.24; p = 0.02). In multivariate analysis, postoperative flexion angle was negatively correlated with BMI (β = - 0.243; p < 0.01), whereas it was positively correlated with preoperative flexion (β = 0.406; p < 0.01) and PT (β = 0.279; p < 0.01). A negative correlation was found between PTS and PT (R = - 0.39, p < 0.01). An increase in posterior laxity at 90 degrees of flexion significantly increased postoperative flexion. An increase in PTS was associated with decreased posterior laxity; however, it had no effect on postoperative flexion.

Total knee arthroplasty systems are continually being updated. Evaluating these new systems for their effectiveness, and potential complications is vital, and is closely monitored by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). The ATTUNE Knee System was released in 2013, and some early studies reported on an increase in rates of aseptic loosening. This study aims to investigate the revision rates of the ATTUNE Knee System and its predecessor the PFC Sigma utilizing registry data. Data were collected from AOANJRR. All ATTUNE and PFC Sigma primary total knee replacements (TKR) performed between September 1999 until 2021 were included. The primary outcome measures were revision rates and indications for revision. A total of 38,407 primary TKRs were included in the study (24,863 ATTUNE, 13,544 PFC Sigma). The cumulative percentage revision (CPR) at 8 years was 3.3% (95% confidence interval [CI]: 2.6, 4.1) for the ATTUNE Knee System and 3.2% (95% CI: 2.9, 3.5) for the PFC Sigma Knee System (p = 0.144). The proportion of revisions due to aseptic loosening was 20.5% for the ATTUNE Knee System and 21.5% for the PFC Sigma Knee System. Midterm revision rates of the ATTUNE and PFC Sigma Knee Systems are not significantly different. Additionally, the percentage of revisions due to aseptic loosening of the implant were not significantly different between the two knee systems.

During anterior cruciate ligament (ACL) reconstruction, intraoperative graft contamination or postoperative infection remains a notable clinical concern. While antiseptic solutions are increasingly employed for graft decontamination and infection prophylaxis, the potential impact of these agents on the biomechanical integrity of tendon grafts has not been fully elucidated. This experimental study aimed to evaluate the biomechanical effects of soaking tendon grafts in vancomycin, chlorhexidine, and povidone-iodine solutions. Fresh bovine deep digital flexor tendons were used to simulate ACL autografts and randomly assigned to four groups (n = 6): 4% chlorhexidine, 10% povidone-iodine, 5 mg/mL vancomycin, and 0.9% isotonic saline (control). After 30-minute soaking, tendons were sutured using a four-rip-stop technique and biomechanically tested using a servohydraulic tensile system. Failure load, stiffness, and cyclic elongation were measured. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests with Bonferroni correction. Vancomycin and chlorhexidine groups exhibited significantly lower cyclic elongation compared to control and povidone-iodine groups. Failure load was also significantly higher in these groups, particularly compared to povidone-iodine, which demonstrated the weakest biomechanical performance. No significant differences in stiffness were observed across groups. Vancomycin and chlorhexidine can be safely used for short-term antiseptic soaking without compromising graft mechanical integrity. In contrast, povidone-iodine may weaken tendon structure. These findings may guide antiseptic use during ACL reconstruction and in managing contaminated tendons in open injuries.

Anatomic research has demonstrated significant differences in native knee morphology between genders and ethnicities. These studies have traditionally evaluated femoral morphology. However, no studies have yet investigated possible relationships between the posterior femoral condyles and the tibial plateau. Our study sought to demonstrate this relationship and evaluate its strength when stratified by gender and race. An international database of CT scans of non-arthritic knees was accessed, and, using computer software, length measurements of regions of interest were recorded. Measurements included medial-lateral width of the posterior femoral condyles and width of the tibial plateau (TW). These measurements were compared. Statistical analysis was performed for the entire population, and subsequently for the population stratified by gender and ethnic groupings. The review included 373 non-arthritic knees, each from a unique patient. The cohort consisted of 184 males (49.3%) and 189 females (50.6%). About 117 patients were from Japan (31.4%), 100 were from India (26.8%), 87 were from South Korea (23.3%), 43 were from China (11.5%), and 26 were from North America (7.0%). The average age was 57.6 ± 8.6 years. The width of the proximal tibia was positively correlated to posterior femoral condylar width, R ² = 0.83. Gender stratification weakened the correlation, with female patients demonstrating an R ² of 0.64 and male patients an R ² of 0.60. Ethnic stratification strengthened relationships in Japanese (R ² = 0.87), North American (R ² = 0.89), and South Korean (R ² = 0.88) patients; and weakened them in Indian (R ² = 0.72) and Chinese (R ² = 0.82) patients. This study is the first to use CT to demonstrate the strength of tibiofemoral relationships for individual demographic groups. These findings highlight important differences in morphology and may be used to inform implant design, selection, stocking, and supply. Further, these data may help identify patients who require different-sized tibial and femoral components preoperatively.

Total knee arthroplasty (TKA) is one of the most effective treatment options for patients with end-stage osteoarthritis of the knee. However, one out of five patients remains unhappy with the outcomes. In recent years, more emphasis has been given to knee alignment approaches as a potential solution. The main objective of this study was to compare the clinical and functional outcomes between patients undergoing robot-assisted TKA using mechanical alignment (MA) or functional alignment (FA). This prospective nonrandomized study enrolled 40 patients (20 patients in each group). The procedure was performed by a single surgeon using FA or MA. In addition to other measures, the New Knee Society Score (NKSS) and Oxford Knee Score (OKS), and modified forgotten joint scores (MFJS) were recorded, and the patients were followed up until 18 months. The baseline characteristics, including age, gender, and body mass index, did not differ statistically between the groups. All parameters of the NKSS, the OKS, and the MFJS were improved at 18 months in the FA-TKA group compared with the MA-TKA group. The pain score and time to straight leg raise were better in the FA-TKA versus the MA-TKA group (p < 0.001). This study suggests that robotic TKA with the FA approach could improve patient satisfaction, along with fulfillment of patients' expectations from the surgery, through 18 months of follow-up compared with the MA approach. Due to the small sample size of this study, future studies are needed to confirm these findings.

As patients place higher demand on their implants, mid-flexion instability is increasingly recognized as a contributor to dissatisfaction after total knee arthroplasty (TKA). However, the outcomes of revision surgery to address mid-flexion instability have not been categorized. The study cohort was composed of 52 patients who underwent revision surgery for mid-flexion or combined flexion and mid-flexion instability by a single surgeon between 2015 and 2022. The mean follow-up duration was 2.76 years. Patient characteristics, implants used, and complications were recorded. Range of motion and patient-reported outcomes (collected using the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement [KOOS Jr.] and EuroQol-5 Dimensions-5 Levels [EQ-5D-5L] questionnaires) were compared before surgery and at final follow-up. Five patients (9.6%) required an additional operation. Causes of reoperations included component loosening, persistent wound drainage, recurrent instability, and arthrofibrosis. KOOS Jr. scores improved from 46 preoperatively to 60 postoperatively (p < 0.01). EQ-5D-5L scores demonstrated a reduction in pain/discomfort and an improvement in the ability to perform usual activities (p < 0.05). A trend was observed toward increased mobility (p = 0.05). The most common 30-day complications were transfusion (11.5%), readmission (11.5%), renal complications including acute kidney injury (9.6%), and wound complications (5.8%). Patients had improvements in maximum flexion and total arc of motion postoperatively (p < 0.05). This study includes the largest cohort of patients undergoing revision for mid-flexion instability and demonstrates that appropriately selected patients can have improved outcomes while maintaining their range of motion.

Patient-reported outcome measures (PROMs) are crucial in evaluating the success of primary total knee arthroplasty (TKA). This study aimed to determine the individual significance of each question of the Knee Osteoarthritis Outcome Score (KOOS) and the Veterans RAND 12 (VR-12) Mental Composite Score (MCS) in achieving a Patient Acceptable Symptom State (PASS). A prospectively collected cohort of 9,942 unilateral elective TKAs was analyzed. Responses were collected for 17 KOOS questions (KOOS-Pain subscore, KOOS-Physical Function Short form [PS], and KOOS-Joint related [JR]) and 6 MCS questions preoperatively and 1-year postoperatively. Achievement of PASS was assessed through a positive response to a binary satisfaction-related question. The association between responses to questions and outcomes was examined via multivariable logistic regression models. A poorer preoperative response to knee pain frequency (odds ratio [OR] = 0.86 [0.77-0.97], p = 0.017) and knee pain while sitting or lying (OR = 0.88 [0.79-0.99], p = 0.029) was independently associated with reduced odds of achieving PASS at 1-year post-TKA. A more favorable preoperative response in knee pain during full knee straightening was independently associated with an increased odds of PASS attainment (OR = 1.10 [1.01-1.19], p = 0.035). No other metric was independently associated with PASS attainment at 1 year. Individual KOOS questions evaluating knee pain frequency, knee pain while sitting or lying down, and knee pain during full knee straightening were linked to patient satisfaction 1 year following TKA. Patients experiencing frequent or persistent knee pain at rest may represent those with more advanced joint disease or heightened pain sensitivity, contributing to lower postoperative satisfaction. Conversely, patients reporting minimal or no pain during specific movements, such as full knee straightening, likely had a less severe baseline condition, making their postoperative expectations more easily attainable, thereby leading to higher satisfaction.Level of evidence III.