ObjectiveA prospective randomized controlled study was conducted to investigate the early postoperative analgesic effectiveness of using liposomal bupivacaine (LB) for local infiltration anesthesia (LIA) in unicompartmental knee arthroplasty (UKA). Methods Between January 2024 and July 2024, a total of 80 patients with knee osteoarthritis (KOA) who met the selection criteria were enrolled in the study. Patients were randomly assigned to either the LB group or the “cocktail” group in a 1∶1 ratio using a random number table, with 40 patients in each group. Baseline characteristics, including gender, age, body mass index, operated side, Kellgren-Lawrence grade, and preoperative American Society of Anesthesiologists (ASA) classification, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and knee joint range of motion, showed no significant difference between the two groups (P>0.05). Both groups received LIA and comprehensive pain management. The surgical duration, incision length, pain-related indicators [resting and activity visual analogue scale (VAS) scores, total dosage of oral morphine, WOMAC scores], knee joint range of motion, first ambulation time after operation, length of hospital stay, and postoperative adverse events. ResultsThere was no significant difference between the two groups in surgical duration, incision length, first ambulation time after operation, length of hospital stay, total dosage of oral morphine, and pre-discharge satisfaction with surgery and WOMAC scores (P>0.05). At 4, 12, and 24 hours after operation, the resting and activity VAS scores in the “cocktail” group were lower than those in the LB group; at 60 and 72 hours postoperatively, the resting VAS scores in the LB group were lower than those in the “cocktail” group, with the activity VAS scores also being lower at 60 hours; all showing significant differences (P<0.05). There was no significant difference in the above indicators between the two groups at other time points (P>0.05). On the second postoperative day, the sleep scores of the LB group were significantly higher than those of the “cocktail” group (P<0.05), while there was no significant difference in sleep scores on the day of surgery and the first postoperative day (P>0.05). Additionally, the incidence of complications showed no significant difference between the two groups (P>0.05). ConclusionThe use of LB for LIA in UKA can provide prolonged postoperative pain relief; however, it does not demonstrate a significant advantage over the “cocktail” method in terms of short-term analgesic effects or reducing opioid consumption and early functional recovery after UKA. Nevertheless, LB may help reduce postoperative sleep disturbances, making it a recommended option for UKA patients with cardiovascular diseases and insomnia or other mental health issues.
The surgical installation accuracy of the components in unicompartmental knee arthroplasty (UKA) is an important factor affecting the joint function and the implant life. Taking the ratio of the medial-lateral position of the femoral component relative to the tibial insert (a/A) as a parameter, and considering nine installation conditions of the femoral component, this study established the musculoskeletal multibody dynamics models of UKA to simulate the patients’ walking gait, and investigated the influences of the medial-lateral installation positions of the femoral component in UKA on the contact force, joint motion and ligament force of the knee joint. The results showed that, with the increase of a/A ratio, the medial contact force of the UKA implant was decreased and the lateral contact force of the cartilage was increased; the varus rotation, external rotation and posterior translation of the knee joint were increased; and the anterior cruciate ligament force, posterior cruciate ligament force and medial collateral ligament force were decreased. The medial-lateral installation positions of the femoral component in UKA had little effect on knee flexion-extension movement and lateral collateral ligament force. When the a/A ratio was less than or equalled to 0.375, the femoral component collided with the tibia. In order to prevent the overload on the medial implant and lateral cartilage, the excessive ligament force, and the collision between the femoral component and the tibia, it is suggested that the a/A ratio should be controlled within the range of 0.427−0.688 when the femoral component is installed in UKA. This study provides a reference for the accurate installation of the femoral component in UKA.
ObjectiveTo summarize the priority and indications of the unicompartmental knee arthroplasty (UKA) and the evolution of minimally invasive surgery-UKA (MIS-UKA), and to discuss the effectiveness. MethodsThe related literature on UKA was extensively reviewed, summarized, and analyzed. ResultsRecently, satisfactory results has been achieved in UKA for the treatment of single room knee osteoarthritis. Both the design of the single condyle prosthesis and the surgical technique are becoming more advanced, which make the MIS-UKA possible. Especially the application of navigation computer and robot assisted system on UKA improves the accuracy of unicompartmental prosthesis implantation greatly. ConclusionThe superiority and indications of MIS-UKA are gradually expanding with the progress of surgical technique and the design of the single condyle prosthesis. However, whether the application of navigation computer and robot assisted system can improve the effectiveness needs to be further confirmed.
ObjectiveTo compare the early effectiveness and safety of simultaneous bilateral and staged bilateral unicompartmental knee arthroplasty (UKA) in treatment of anteromedial compartment osteoarthritis.MethodsThe clinical data of 31 patients with bilateral anteromedial compartment osteoarthritis who underwent bilateral UKAs between January 2015 and January 2017 was retrospectively analyzed. Of them, 17 patients were treated with simultaneous bilateral UKAs (simultaneous group) and 14 patients with staged bilateral UKAs (staged group). There was no significant difference in gender, age, body mass index, osteoarthritis grading, and preoperative hip-knee-ankle angle, knee society score (KSS), visual analogue scale (VAS) score, and range of motion (ROM) of knee between the two groups (P>0.05). The operation time, blood loss, hospitalization stay, minimum hemoglobin value during 10 days after operation, and hospitalization cost were recorded. The staged group was compared by the sum of two operations. The effectiveness was evaluated by KSS score, VAS score, ROM at 3, 6, 12 months after operation, and patient satisfaction scores were recorded at 12 months after operation.ResultsThe operation time, hospitalization stay, and hospitalization cost of the simultaneous group were significantly lower than those of the staged group (P<0.05). There was no significant difference in blood loss and the minimum hemoglobin value during 10 days after operation between the two groups (P>0.05). Superficial infection occurred in 1 side of 1 case (7.1%) in staged group. Postoperative delirium occurred in 1 case (5.9%) in simultaneous group. There was no significant difference in incidence of postoperative complications between the two groups (P=1.000). Patients in both groups were followed up 12-32 months (mean, 24.7 months). There was no significant difference in KSS score between the two groups at 3 months after operation (t=0.896, P=0.392). KSS scores were significanly higher in simultaneous group than in staged group at 6 and 12 months after operation (P<0.05). There was no significant difference in ROM and VAS scores between the two groups at 3, 6, and 12 months after operation (P>0.05). At 12 months after operation, the patient satisfaction scores were significantly higher in simultaneous group than in staged group (P<0.05). X-ray films showed no loosening of the prosthesis in the two groups.ConclusionSimultaneous bilateral UKAs has the same security as staged bilateral UKAs. Meanwhile knee function recovery was better, hospitalization stay and hospitalization cost reduced, and patient satisfaction was higher in simultaneous bilateral UKAs.
ObjectiveTo summarize research progress of change in bone mineral density (BMD) after knee arthroplasty and its diagnostic methods, influencing factors, and drug prevention and treatment.MethodsThe relevant literature at home and abroad was reviewed and summarized from research status of the advantages and disadvantages of BMD assessment methods, the trend of changes in BMD after knee arthroplasty and its influencing factors, and the differences in effectiveness of drugs.ResultsThe central BMD and mean BMD around the prosthesis decrease after knee arthroplasty, which is closely associated with body position, age, weight, daily activities, and the fixation methods, design, and material of prosthesis. Denosumab, bisphosphonates, and teriparatide et al. can decrease BMD loss after knee arthroplasty.ConclusionBMD after knee arthroplasty decreases, which is related to various factors, but the mechanism is unclear. At present, some inhibitors of bone resorption can decrease BMD loss after knee arthroplasty. However, its long-term efficacy remains to be further explored.
Objective To conclude the research progress of unicompartmental knee arthroplasty (UKA) in the treatment of elderly patients with knee osteoarthritis (KOA). Methods The literature on UKA at home and abroad in recent years was reviewed to summarize the clinical characteristics of elderly patients with KOA, perioperative management (including evaluating indications preoperatively, intraoperative prosthesis selection, postoperative complication management, etc). Results Through reasonable preoperative evaluation, prosthesis selection, and advanced perioperative management, for elderly patients with KOA who meet the indications, UKA can be considered. Compared with total knee arthroplasty, the incidence of postoperative complications in elderly patients undergoing UKA is lower, joint awareness is reduced, functional improvement and satisfaction are higher. Meanwhile, choosing appropriate prostheses and fixation methods can lead to a good survival rate. ConclusionUKA can provide a safe and effective treatment option for elderly patients with KOA within a certain range of indications.
ObjectiveTo evaluate the effectiveness of Oxford mobile-bearing bipolar prosthesis unicompartmental knee arthroplasty (UKA) in the treatment of single compartmental knee osteoarthritis. MethodsBetween June 2011 and July 2013, 22 cases of single compartmental knee osteoarthritis were treated by Oxford mobile-bearing bipolar prosthesis UKA. Of 22 cases, 8 were male and 14 were female with an average age of 65 years (range, 45-80 years); the left knee was involved in 12 cases, and the right knee in 10 cases, with a mean disease duration of 32.5 months (range, 8-90 months). The mean weight was 55.2 kg (range, 50-65 kg), and the mean body mass index was 20.8 kg/m2(range, 17-25 kg/m2). Osteoarthritis involved in the single knee medial compartment in all patients. Knee society score (KSS) and range of motion (ROM) were measured to evaluate the knee joint function. ResultsPrimary healing of incision was obtained in all patients, and there was no complication of infection, bedsore, or deep venous thrombosis. Postoperative follow-up was 2-4 years (mean, 3.2 years). The X-ray films showed good position of prosthesis, no prosthesis dislocation, or periprosthetic infection during follow-up. Knee ROM, KSS function score, and KSS clinical score were significantly improved at 1 week after operation and at last follow-up when compared with preoperative ones (P<0.05), but no significant difference was shown between at 1 week and at last follow-up (P>0.05). ConclusionOxford mobile-bearing bipolar prosthesis UKA is an effective method to treat single compartmental knee osteoarthritis, with the advantages of less trauma, earlier rehabilitation exercise, near physiological state in joint function, and less risk of complications.
ObjectivesTo systematically review the efficacy of unicompartmental knee arthroplasty on forgotten joint score (FJS) in patients with knee osteoarthritis.MethodsPubMed, EMbase, The Cochrane Library, Web of Science, CNKI, CBM, WanFang Data and VIP databases were electronically searched to collect randomized controlled trials (RCTs) and cohort studies on unicompartmental knee arthroplasty on FJS in patients with knee osteoarthritis from inception to December 31st, 2019. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 2 RCTs and 11 cohort studies were included. The results of meta-analysis based on RCTs showed that: compared to posterior stabilized total knee arthroplasty (PS-TKA), unicompartmental knee arthroplasty could improve FJS on 12-month (MD=9.23, 95%CI 0.53 to 17.93, P=0.04) after operation. The results of meta-analysis based on cohort studies showed that: compared to PS-TKA, unicompartmental knee arthroplasty could improve FJS on 6-week (MD=8.90, 95%CI 6.87 to 10.94, P<0.000 01), 6-month (MD=18.72, 95%CI 8.71 to 28.74, P=0.000 2), 1-year after operation (MD=13.41, 95%CI 8.87 to 17.95, P<0.000 01), and the last follow-up (MD=0.99, 95%CI 0.47 to 1.54, P=0.000 2).ConclusionsCurrent evidence shows that, comparing with PS-TKA, unicompartmental knee arthroplasty in knee osteoarthritis shows advantage in the improvement of FJS. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify above conclusions.
Objective To conclude the failure factors of unicompartmental knee arthroplasty (UKA), and summarize the research progress of revision surgery. MethodsThe literature on UKA at home and abroad in recent years was reviewed to summarize its risk factors, treatment methods, including the evaluation of bone loss, prosthesis selection, and surgical techniques. ResultsThe factors inducing UKA failure mainly include improper indications, technical errors, and others. The application of digital orthopedic technology can reduce failures caused by surgical technical errors and shorten the learning curve. There are a variety of options for revision surgery after UKA failure, including polyethylene liner replacement, revision with UKA or total knee arthroplasty, with adequate preoperative evaluation prior to implementation. The biggest challenge in revision surgery is the management and reconstruction of bone defects. ConclusionThere is a risk of failure in UKA, which needs to be treated with caution and should be determined according to the type of failure.
Objective To investigate the effect of accuracy of phase 3 Oxford prosthesis positioning on short-term effectiveness of unicompartmental knee arthroplasty (UKA). Methods The clinical data of 26 patients (26 knees) who were treated with UKA between September 2015 and November 2015 was retrospectively analyzed. The single-peg Oxford prosthesis was implanted in 15 patients (single-peg group), and twin-peg Oxford prosthesis was implanted in 11 patients (twin-peg group). There was no significant difference in gender, age, body mass index, Kellgren-Lawrence grading, and preoperative Hospital for Special Surgery (HSS) scores between 2 groups (P>0.05). HSS, knee society score (KSS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and Oxford knee score (OKS) were used to evaluate the knee function. Radiographic criteria for Oxford UKA was used to evaluate the prosthesis position. The reason and treatment of bearing dislocations were recorded. Results All patients were followed up with mean follow-up time of 26.2 months in single-peg group (range, 24-27 months) and 25.2 months in twin-peg group (range, 24-26 months). The bearing dislocation occurred in 2 cases of twin-peg group during follow-up. At last follow-up, there was no significant difference in HSS, WOMAC, OKS, and KSS scores between 2 groups (P>0.05). There was no significant difference in radiographic scores of femoral component, tibial component, and overall components between 2 groups (P>0.05). No significant correlation was found between radiographic scores and postoperative functional outcome in 2 groups (P>0.05). Conclusion Within a safe range, the accuracy of phase 3 Oxford prosthesis positioning has limited influence on the short-term functional outcome.