【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 evaluate the short-term effectiveness of unicompartmental knee arthroplasty (UKA) for medial compartmental osteoarthritis of the knee. MethodsBetween January 2008 and October 2013, 18 patients with medial compartmental osteoarthritis of the knee were treated by UKA, including 11 males and 7 females with an average age of 67.2 years (range, 60-72 years). The disease duration ranged from 3 to 5 years (mean, 3.7 years). All patients had loading pain and walk-associated pain of the medial compartmental knee. The preoperative visual analogue scale (VAS) score was 6.8±1.4. The full-length radiograph of lower limb and anteroposterior and lateral radiographs of the knee showed medial compartmental osteoarthritis of the knee. According to Ahlback staging, 8 knees were at stageⅡand 10 knees at stageⅢ. The knee range of motion (ROM) was (112.3±11.3)°, and the angle of genu varus was (13.2±1.3)°. The American Hospital for Special Surgery (HSS) score was 59.0±6.4. ResultsPrimary healing of incision was obtained in all patients, and no infection or lower limb deep venous thrombosis occurred. All of the patients were followed up 6-50 months (mean, 28 months). No prosthetic loosening and dislocation or lesions of contralateral compartment and patellofemoral joint developed. At 6 months after operation, the VAS score was significantly reduced to 2.8±1.2 (t=9.20, P=0.00); most of patients achieved significant relief of pain. The HSS score was significantly increased to 92.0±3.1 (t=19.69, P=0.00); and the results were excellent in 12 cases, good in 5 cases, and poor in 1 case, with an excellent and good rate of 94.4%. The knee ROM was (115.2±10.2)°, showing no significant difference when compared with preoperative one (t=-0.81, P=0.23). The alignment of limbs showed that the angle of genu varus was significantly reduced to (6.8±2.1)° (t=10.99, P=0.00). ConclusionUKA has satisfactory short-term effectiveness in the treatment of medial compartmental knee osteoarthritis, however, long-term effectiveness need further studies.
ObjectiveTo explore the short- and mid-term effectivenesses of combined unicompartmental knee arthroplasty (UKA) and anterior cruciate ligament (ACL) reconstruction for osteoarthritis (OA) and ACL injury. MethodsBetween January 2006 and January 2014, 32 patients with knee OA and ACL injury were treated by combined UKA and ACL reconstruction. There were 12 males and 20 females, aged 41-63 years (mean, 50 years); 17 left knees and 15 right knees were involved. The causes of ACL injury were sports injury (25 cases) and traffic accident injury (7 cases), including 27 cases of old injury and 5 cases of acute injury. Pain of the medial compartment of the knee and unstable knee joint were the main clinical symptoms. Preoperative X-ray films showed (3.1±0.6)° of varus deformity. ResultsAll incisions healed by first intention, without complication. The patients were followed up 16-112 months (mean, 55 months). Mobile bearing dislocation occurred in 2 cases after operation, and was cured after replacing much thicker mobile bearings. X-ray films showed (4.0±0.7)° of valgus at last follow-up. There was no loosening of the prosthesis. Physiological radiolucent line (<1 mm) was observed around the tibial component in 10 patients. The Oxford Knee Score (OKS), Knee Society Score (KSS) clinical score, KSS functional score, and Tegner activity score at last follow-up were improved significantly (P<0.05). The range of motion (ROM) of the operated knee was (123.5±2.8)°, and the posterior slope of the tibial component was (3.9±1.2)° at last follow-up; a significant correlation was found between ROM and posterior slope according to the Pearson's correlation (r=0.392, P=0.031). ConclusionCombined UKA and ACL reconstruction has good short- and mid-term effectivenesses for OA and ACL injury.
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 short-term effectiveness of unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) in the treatment of medial compartment osteoarthritis (OA) of the knee so as to provide a reference for clinical selection of appropriate treatment. MethodsBetween January 2010 and June 2011, 28 cases of medial compartment OA of the knee underwent UKA in 16 cases (UKA group) and HTO in 12 cases (HTO group). Biomet Oxford phase Ⅲ unicompartmental knee prosthesis was used in UKA group, and closing wedge osteotomy in HTO group. There was no significant difference in gender, age, course of disease, side, body mass index, articular cartilage degeneration classification, preoperative knee range of motion (ROM), Lysholm knee score, Tegner activity score, and femorotibial angle (FTA) between the 2 groups (P>0.05). The patients of UKA group began weight-bearing walking with walking aids within 48 hours after operation, and the patients of HTO group began weight-bearing walking with walking aids at 6 weeks after operation, and gradually began full weight-bearing walking at 8-12 weeks. ResultsThere was no significant difference in operation time and intraoperative blood loss between 2 groups (t=0.406, P=0.688; t=-1.552, P=0.133). All incision healed primarily in both groups. No complications occurred in 2 groups. All patients were followed up 3.5 years on average (range, 3.0-4.5 years) in UKA group and 3.6 years on average (range, 3-4 years) in HTO group. There were significant differences in Lysholm knee score, Tegner activity score, and FTA in the 2 groups between before and after operation (P<0.05), but there was no significant difference in knee ROM (P>0.05). At last follow-up, there was no significant difference in all above indexes between 2 groups (P>0.05). The postoperative X-ray showed that all force lines of the lower limbs were corrected, and the prosthesis and internal fixation were fixed reliably. During follow-up, Kellgren-Lawrence Ⅱ degeneration of the lateral compartment was observed in 1 case of 2 groups respectively; Kellgren-Lawrence Ⅱ degeneration of the patellofemoral joint was observed in 1 case of the HTO group, there was no significant difference between the 2 groups (χ2=0.778, P=0.378). ConclusionBoth UKA and HTO have good short-term effectiveness for treating unicompartmental OA; however, the long-term effectiveness need further study and follow-up.
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.
ObjectiveTo conclude the revision reason of unicompartmental knee arthroplasty (UKA) using computer-assisted technology so as to provide reference for reducing the revision incidence and improving the level of surgical technique and rehabilitation. MethodThe relevant literature on analyzing revision reason of UKA using computer-assisted technology in recent years was extensively reviewed. ResultsThe revision reasons by computer-assisted technology are fracture of the medial tibial plateau, progressive osteoarthritis of reserved compartment, dislocation of mobile bearing, prosthesis loosening, polyethylene wear, and unexplained persistent pain. ConclusionsComputer-assisted technology can be used to analyze the revision reason of UKA and guide the best operating method and rehabilitation scheme by simulating the operative process and knee joint activities.
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.
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.
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.