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.
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.
Objective To summarize the research progress of Oxford unicompartmental knee arthroplasty (UKA) in treating partial thickness cartilage loss (PTCL) in the medial compartment of the knee joint, aiming to further clarify the indications and optimize the effectiveness of Oxford UKA. MethodsA comprehensive review of recent domestic and international literature on Oxford UKA for PTCL in the medial compartment of the knee joint was conducted to summarize its application and research advancements. ResultsBased on current researches, the main indication for Oxford UKA is full thinckness cartilage loss in the medial compartment of the knee joint. Although it has shown certain effectiveness in treating PTCL in the medial compartment of the knee joint, there are also reports of opposite conclusions. Therefore, there is still controversy over whether Oxford UKA can be chosen for PTCL, and the large-sample and multi-center studies are needed to further clarify the controversy. Studies indicate that accurate preoperative assessment of cartilage damage severity is crucial for selecting appropriate candidates for Oxford UKA to optimize postoperative effectiveness. ConclusionOxford UKA may represent an effective treatment for patients with PTCL in the medial compartment of the knee joint. However, strict patient selection and precise preoperative evaluation are essential to ensure surgical success and long-term effectiveness.
Unicompartmental knee arthroplasty (UKA) has a long history and has many advantages in some aspects over total knee arthroplasty (TKA) for patients with suitable indications, but it has not been established as a treatment at the same level with TKA. Therefore, 80 members of the British Association for Surgery of the Knee (BASK) and the European Knee Society (EKS) were invited to attend a joint meeting with the aim of creating an evidence-based consensus statement on UKA, in London, UK (December 2019). A formal consensus process was undertaken at the meeting incorporating a multiple round Delphi exercise, with group discussion of areas of agreement and disagreement between rounds. Five consensus statements were issued: ① UKA should be offered as a successful alternative to TKA in patients undergoing arthroplasty who meet agreed indications. ② When consenting a patient for UKA, information including the benefits and risks that are specific to UKA, should be tailored to and discussed with the individual patient. ③ Evidence suggests that surgeons should avoid low-volume use of UKA to optimise outcomes for their patients. ④ Surgeons should use the contemporary evidence-based indications and contraindications for medial UKA. ⑤ Knee arthroplasty surgeons should have exposure to and training in UKA. On the basis of full study of the consensus, combined with the Expert Consensus on Perioperative Management of Unicompartmental Knee Arthroplasty in China in 2020, this paper elaborates the meaning of the final evidence-based consensus for clinicians’ reference.
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.
【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.
ObjectiveTo investigate the effect of anterior cruciate ligament (ACL) integrity on the short- and mid-term effectiveness of mobile-bearing medial unicompartmental knee arthroplasty (UKA). MethodsThe clinical data of 128 patients with anteromedial osteoarthritis who underwent mobile-bearing medial UKA between June 2019 and June 2021 was retrospectively analyzed. According to the integrity of ACL structure under direct vision during operation, the patients were divided into normal group (30 cases), synovial defect group (53 cases), and longitudinal split group (45 cases). There was no significant difference in gender, age, body mass index, preoperative knee range of motion (ROM), hip-knee-ankle angle (HKA), Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and other baseline data among the 3 groups (P>0.05). The knee ROM, KSS score (including clinical and functional scores), WOMAC score (including pain, stiffness, and function scores) before operation and at last follow-up, the Lysholm score, International Knee Documentation Committee (IKDC) score, and Forgetting Joint Score (FJS-12) at last follow-up were recorded and compared among the 3 groups. Imaging examination was performed to evaluate the wear of cartilage in the lateral tibiofemoral compartment and patellofemoral compartment of the knee joint. HKA and posterior tibial slope (PTS) were measured at last follow-up. ResultsAll the patients of 3 groups were followed up 22-56 months (mean, 40.4 months). There was no significant difference in follow-up time among the 3 groups (P>0.05). At last follow-up, imaging examination showed no obvious cartilage wear progression of the lateral tibiofemoral compartment and patellofemoral compartment, and no adverse events such as aseptic loosening of the prosthesis, dislocation of the removable pad, or infection occurred during the follow-up. At last follow-up, knee ROM, HKA, KSS scores, and WOMAC scores of the 3 groups significantly improved when compared with preoperative ones (P<0.05). There was no significant difference in the changes of the above indicators before and after operation, and also the Lysholm score, IKDC score, FJS-12 score, and PTS among the 3 groups (P>0.05). ConclusionThe integrity of ACL has no significant effect on the short- and mid-term effectiveness of mobile-bearing medial UKA.
Objective To investigate the effect of Navio robot-assisted unicompartmental knee arthroplasty (UKA) on the biomechanics of knee joint during sitting-up movement, and to determine whether UKA can maintain the biomechanical characteristics of knee joint. Methods The clinical data of 8 patients with medial compartment osteoarthritis treated with medial fixed platform of Navio robot-assisted UKA between January 2018 and January 2019 and had the complete follow-up data were retrospectively analyzed. There were 4 males and 4 females; the age ranged from 58 to 67 years, with an average of 62.3 years. The disease duration was 6-18 months, with an average of 13 months. The varus deformity ranged from 4° to 6°, with an average of 5°; the knee flexion range of motion was 0°-130°, with an average of 110°. All patients had no extension limitation. The imaging data of bilateral knees during sitting-up movement were collected by biplane C-arm X-ray machine at 3 weeks before operation and 7 months after operation. The three-dimensional models of femur and tibia were established by dual-energy CT scanning, and the three-dimensional models of femur and tibia were matched and synchronized with the femur and tibia in X-ray film by automatic matching tracer software. The biomechanical parameters of femur and tibia were measured, including internal rotation/external rotation, varus/valgus, forward/backward displacement of medial and lateral tibia contact center, and lateral compartment joint space. Results Eight patients were followed up 5-7 months, with an average of 6.4 months. In the comparison of the affected side before and after operation, except for the difference of varus/valgus which was significant (t=4.959, P=0.002), the differences in other indicators was not significant (P>0.05). There were significant differences in varus/valgus and internal rotation/external rotation between healthy and affected sides at 3 weeks before operation (P<0.05), and the differences in other indicators was not significant (P>0.05). At 7 months after operation, the difference in the forward and backward displacement of medial tibia contact center was significant (t=3.798, P=0.007), and the differences in other indicators was not significant (P>0.05). Conclusion UKA can effectively correct the varus and valgus of the knee joint, and restore the rotational biomechanical characteristics of the affected knee joint. It does not affect the establishment of the lateral compartment joint space, but the medial and lateral tibia contact center still changes.
Objective To investigate the short- and mid-term effectiveness of unicompartmental knee arthroplasty (UKA) for post-traumatic arthritis (PTA) of knee. Methods The clinical data of 30 patients with PTA of unilateral knee between March 2014 and September 2021 was retrospectively analyzed. There were 14 males and 16 females with an average of 64.5 years (range, 33-81 years). The average body mass index was 26.7 kg/m2 (range, 19.8-35.6 kg/m2). The types of injuries that caused PTA included intra-articular fracture in 16 cases, extra-articular fracture in 8 cases, and soft tissue injury in 6 cases. The initial injuries were treated by conservative therapy in 12 cases and by surgical therapy in 18 cases. Ten cases were medial compartment osteoarthritis and 20 cases were lateral compartment osteoarthritis. According to Kellgren-Lawrence staging, there were 19 cases of grade Ⅲ and 11 cases of grade Ⅳ. The operative time, the length of hospital stay, complications, and subjective satisfaction were recorded. The Oxford Knee Function Score (OKS), Hospital for Special Surgery (HSS) score, and knee range of motion (ROM) were used to evaluate knee function. Weight-bearing X-ray films were taken to measure the femoro-tibial angle (FTA) and to assess alignment correction of the lower limb. Results The operative time ranged from 50 to 95 minutes (mean, 63.7 minutes), the length of hospital stay ranged from 3 to 8 days (mean, 6.9 days). Superficial infection occurred in 2 patients, while the remaining incisions healed by first intention. There was no deep vein thrombosis or neurovascular injury. All patients were followed up 17-109 months (median, 70 months). At last follow-up, OKS score, HSS score, and ROM in 30 cases significantly improved when compared with those before operation (P<0.05). Lower limb alignment was significantly corrected and there was significant difference in FTA of the varus and valgus knees between pre- and post-operation (P<0.05). The patient satisfaction rate was 86.7% (26/30). Two cases developed contralateral osteoarthritis progression during follow-up. No bearing dislocation, prosthesis loosening or sinking occurred and none required further revision. Conclusion For patients with PTA of knee, UKA can obtain definite short- and mid-term effectiveness with high patient satisfaction.