ObjectiveTo investigate the short-term effectiveness of unicompartmental knee arthroplasty (UKA) in the treatment of knee osteoarthritis of super-age patients over 85 years old.MethodsSenile patients with unilateral compartment osteoarthritis of the knee who received UKA between November 2013 and May 2017 and met the inclusion criteria were enrolled as the research objects. Among them, 40 patients (50 knees) were more than 85 years old (super-age group) and 44 patients (50 knees) were 52-81 years old (control group). There was significant difference in age between the two groups (t=17.33, P=0.00). There was no significant difference in body mass index, degenerative classification of medial and lateral compartments, varus deformity of knee, disease duration, complicating diseases, and preoperative hemoglobin, hematocrit (HCT), American Hospital for Special Surgery (HSS) score, range of motion (ROM) of knee, visual analogue scale (VAS) score, and femoral-tibial angle (FTA) between the two groups (P>0.05). Hospital stay, hemoglobin, and HCT of the two groups were recorded before operation and on the first day after operation. The changes of hemoglobin and HCT after operation were calculated. During follow-up period, the ROM of the knee, HSS score, and VAS score were measured; the position of the prosthesis and FTA were observed by X-ray films.ResultsThere was no significant difference in hospital stay between the two groups (t=1.05, P=0.29). Hemoglobin and HCT of the two groups on the first day after operation were significantly lower than those before operation (P<0.05). There was no significant difference in the postoperative changes of hemoglobin and HCT between the two groups (P>0.05). All the patients were followed up completely except 4 cases (5 knees) in the super-age group. The follow-up time ranged from 14 to 44 months of super-age group (mean, 29 months) and 21 to 33 months of control group (mean, 24 months). There were significant differences in HSS score, VAS score, ROM of the knee, and FTA between pre-operation and last follow-up in the two groups (P<0.05). There was significant difference in HSS score between the two groups (P<0.05), and no significant difference was found in ROM, VAS score, and FTA between the two groups (P>0.05). X-ray film showed no adverse position of the prosthesis, infection around the prosthesis, prosthesis loosening, or pathological bright lines.ConclusionUKA combined with reasonable perioperative management in the treatment of super-age patients over 85 years with knee osteoarthritis is safe and feasible, and can obtain satisfactory short-term effectiveness.
ObjectiveTo compare the patient-reported outcomes regarding function, joint amnesia, and the quality of life after unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). Methods The clinical data of patients who received UKA or TKA between September 2017 and June 2018 were retrospectively analyzed. After propensity score matching, 40 patients (40 knees) each in TKA group and UKA group were finally included in the study. There was no significant difference between the two groups in gender, age, body mass index, surgical side, preoperative knee range of motion, Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score, clinical and function scores of knee society score (KSS) (P>0.05). At 2 years after operation, WOMAC score, KSS clinical and function scores were performed on the two groups of patients, and compared with preoperative ones; knee injury and osteoarthritis outcome score-physical function short form (KOOS-PS), short-form 36 health survey scale (SF-36 scale), and forgotten joint score (FJS) were also performed. Results At 2 years after operation, the total score of WOMAC, the clinical and function scores of KSS in the two groups significantly improved when compared with preoperative ones (P<0.05), but there was no significant difference in the total score of WOMAC, the individual score of WOMAC, the clinical and function scores of KSS between the two groups (P>0.05). The total KOOS-PS score in the UKA group was significantly lower than that in the TKA group (t=4.243, P=0.000), and the scores of writhing/knee rotation, kneeling, and squatting in the UKA group were significantly lower than those in the TKA group (P<0.05). The total FJS score in the UKA group was significantly higher than that in the TKA group (t=−6.334, P=0.000). In the UKA group, the scores of 7 items were significantly lower than those of the TKA group (P<0.05) including when walking over 15 minutes, when climbing stairs, when walking on uneven ground, when standing for long periods, when doing housework or gardening, when taking a walk or hiking, and when doing your favorite sport. The SF-36 scales of physiological function, energy, social function, emotional function, and mental health in the UKA group were significantly higher than those in the TKA group (P<0.05). Conclusion Compared with TKA, patients treated with UKA may have better knee function recovery, joint amnesia, and higher quality of life.
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.
ObjectiveTo summarize the clinical application and research progress in unicompartmental knee arthroplasty (UKA).MethodsThe literature related to UKA in recent years was reviewed and the emerging indications, implant options, comparisons between other surgical techniques, and recent advances were summarized.ResultsClinical studies show that UKA has many advantages, such as less trauma, faster recovery, and fewer postoperative complications. At present, the operative indication has been expanded. The body mass index more than 25 kg/m2, less than 60 years old, patellofemoral arthritis, and anterior cruciate ligament dysfunction are no longer considered as contraindications. The prosthesis type in UKA should be selected according to the patient’s condition. In recent years, the robot-assisted UKA can effectively improve the effectiveness, improve patient satisfaction, and reduce postoperative complications.ConclusionWith the development of surgical techniques, designs of prosthesis, and the robotic technology, UKA would be further applicated. As more long-term data on UKA become available, it will further guide clinicians in counseling patients on whether UKA should be performed.
The clinical performance and failure issues are significantly influenced by prosthetic malposition in unicompartmental knee arthroplasty (UKA). Uncertainty exists about the impact of the prosthetic joint line height in UKA on tibial insert wear. In this study, we combined the UKA musculoskeletal multibody dynamics model, finite element model and wear model to investigate the effects of seven joint line height cases of fixed UKA implant on postoperative insert contact mechanics, cumulative sliding distance, linear wear depth and volumetric wear. As the elevation of the joint line height in UKA, the medial contact force and the joint anterior-posterior translation during swing phase were increased, and further the maximum von Mises stress, contact stress, linear wear depth, cumulative sliding distance, and the volumetric wear also were increased. Furthermore, the wear area of the insert gradually shifted from the middle region to the rear. Compared to 0 mm joint line height, the maximum linear wear depth and volumetric wear were decreased by 7.9% and 6.8% at –2 mm joint line height, and by 23.7% and 20.6% at –6 mm joint line height, the maximum linear wear depth and volumetric wear increased by 10.7% and 5.9% at +2 mm joint line height, and by 24.1% and 35.7% at +6 mm joint line height, respectively. UKA prosthetic joint line installation errors can significantly affect the wear life of the polyethylene inserted articular surfaces. Therefore, it is conservatively recommended that clinicians limit intraoperative UKA joint line height errors to –2−+2 mm.
【Abstract】 Objective To evaluate the mid-term effectiveness of Oxford Unicompartmental Knee system Phase III for medial unicompartmental knee osteoarthritis (OA). Methods Between December 2008 and August 2010, 26 patients (32 knees) with medial unicompartmental knee OA were treated. Of 26 patients, 11 were followed up more than 2 years, including 7 males and 4 females (14 knees, 6 left and 8 right knees) with an average age of 62.4 years (range, 50-74 years). All patients had load suffering and tenderness of medial unicompartmental knee, and complicated by varus deformity without limitation of flexion and extension; the disease duration ranged 5-23 years (mean, 11.6 years). According to Ahlback staging, 4 knees were at stage II and 10 knees at stage III. Cemented unicompartmental knee arthroplasty (Oxford Unicompartmental Knee system Phase III) was performed by minimally invasive technique. Results All the incisions were primary healing after operation. Five cases suffered from local ache in the pes anserinus during the first 3 months after operation, which was cured after conservative therapy. Of them, 11 patients were followed up 27.5 months on average (range, 24-30 months). During follow-up, no complication of prosthesis loosening, displacement, arthropathy in the opposite department, or the patellofemoral joint occurred. The range of motion was significantly improved from (109.2 ± 8.7)° preoperatively to (123.5 ± 6.7)° at last follow-up (P lt; 0.05); knee society score (KSS) and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores were all significantly improved (P lt; 0.05). At last follow-up, the femoro-tibial angle was significantly improved (P lt; 0.05); tibial plateau and the tibial anatomical axis increased, showing no significant difference (P gt; 0.05); and posterior tibial slope was significantly decreased (P lt; 0.05). Conclusion Oxford Unicompartmental Knee system Phase III has satisfactory mid-term effectiveness in treating medial unicompartmental knee OA with the advantages of little trauma and rapid recovery, but long-term effectiveness is expected for further follow-up.
Objective To summarize the current research progress about influence of patellofemoral osteoarthritis on clinical outcome of unicompartmental knee arthroplasty (UKA). Methods The recent related literature was extensively reviewed and summarized, including pros and cons to regard the patellofemoral osteoarthritis as the contraindication. Results Previous studies regarded patellofemoral osteoarthritis as the contraindication of UKA. Most of current researches show that the damage to the articular cartilage of the patellofemoral joint to the extent of full-thickness cartilage loss has no influence on outcome of UKA. There is no correlation between preoperative anterior knee pain or medial patellofemoral joint degeneration and the clinical outcome. However, lateral subluxation of the patella has an adverse impact on postoperative curative effect. Degeneration of the lateral patellofemoral joint may be a risk factor of the outcome. Conclusion Patellofemoral osteoarthritis should not be the absolute contraindication of UKA. The effect of degeneration of the lateral patellofemoral joint is not clear at present, and still needs further studies in the future.
ObjectiveTo compare the short-term effectiveness of medial unicompartmental knee arthroplasty (UKA) between patients younger or older than 60 years of age, and to investigate the impact of age on the effectiveness. Methods The clinical data of 182 patients (182 knees) who underwent medial UKA between July 2016 and June 2018 were retrospectively analyzed, of which 72 patients were less than 60 years old (group A) and 110 patients were more than 60 years old (group B). There was a significant difference in age between groups (t=−20.198, P<0.001). No significant difference was found in gender, body mass index, surgical sides, Kellgren-Lawrence grading, disease duration, and preoperative Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score between groups (P>0.05). The postoperative hospital stay and complications were recorded, and the WOMAC score, satisfaction score, and prosthesis revision were compared between groups. Results The length of postoperative hospital stay was (4.50±1.09) days in group A, and (4.46±1.29) days in group B, with no significant difference between groups (t=0.198, P=0.844). All incisions healed by first intention. The incidences of early postoperative complications in groups A and B were 5.6% and 3.6%, respectively, and the difference was not significant (χ2=0.061, P=0.804). All patients were followed up. The follow-up time were 28-50 months (mean, 36 months) in group A and 28-50 months (mean, 35 months) in group B. At last follow-up, the WOMAC scores of both groups significantly improved when compared with those before operation (P<0.05), and there was no significant difference between groups (P>0.05) in the difference before and after operation. The satisfaction scores were 6.6±1.7 in group A and 6.9±1.6 in group B, with no significant difference between groups (t=−1.326, P=0.186). There was no revision surgery in both groups during follow-up period. ConclusionAge has no significant effect on the prognosis of medial UKA, and patients younger than 60 years of age can also obtain good short-term effectiveness.
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.
Objective To summarize the computer assisted navigation and robotics in the classification of knee surgery, and the development, surgical indications and contraindication, effectiveness, and the research progress of computer assisted navigation and robotics in unicompartmental knee arthroplasty (UKA). Methods The related literature on computer assisted navigation and robotics in UKA was extensively reviewed, summarized, and analyzed. Results Recently, satisfactory results have been achieved in UKA for the treatment of single compartmental knee osteoarthritis. With the rapid development of computer navigation and robotic technology gradually combined with clinical practice, the great precision and accuracy of implant have been improved in computer navigation and robotics in UKA surgery. Postoperative function is well recovered, meanwhile, prosthesis survival can be significantly increased. Conclusion Computer assisted navigation and robotics in UKA can greatly improve the accuracy of the implant when compared with traditional UKA. The early effectiveness is satisfactory, but the long-term effectiveness still needs to be further observed.