Analysis of the causes of primary revision after unicompartmental knee arthroplasty: A case series

BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and analyse the causes of revision after UKA.METHODS This is a retrospective case series study in which the reasons for the first revision after UKA are summarized.We analysed the clinical symptoms,medical histories,laboratory test results,imaging examination results and treatment processes of the patients who underwent revision and summarized the reasons for primary revision after UKA.RESULTS A total of 13 patients,including 3 males and 10 females,underwent revision surgery after UKA.The average age of the included patients was 67.62 years.The prosthesis was used for 3 d to 72 months.The main reasons for revision after UKA were improper suturing of the surgical opening(1 patient),osteophytes(2 patients),intra-articular loose bodies(2 patients),tibial prosthesis loosening(2 patients),rheumatoid arthritis(1 patient),gasket dislocation(3 patients),anterior cruciate ligament injury(1 patient),and medial collateral ligament injury with residual bone cement(1 patient).CONCLUSION The causes of primary revision after UKA were gasket dislocation,osteophytes,intra-articular loose bodies and tibial prosthesis loosening.Avoidance of these factors may greatly reduce the rate of revision after UKA,improve patient satisfaction and reduce medical burden.

A Research on the Early Effect of Unicompartmental Knee Arthroplasty for Unicompartment Osteoarthritis of the Knee

Objective: To evaluate the early clinical effect of unicompartmental knee arthroplasty (UKA) for medial unicompartment osteoarthritis of knee in the old people, providing the evidence for the treatment of clinic. Methods: From January of 2016 to January of 2017, 20 cases of knee osteoarthritis in medial unicompartment were treated by unicompartmental knee arthroplasty. The knee joint range of motion (ROM), visual analogue scale (VAS) and knee functional Hospital for Special Surgery (HSS) scores were preoperatively recorded. The loss of blood and time of operation were intraoperative recorded. The satisfaction of patient, knee joint range of motion (ROM) and knee functional special surgical hospital score (HSS score) were postoperatively recorded at one year. Results: All patients have been followed up at an average of twelve months. The operation time was 94 - 135 min, mean 105.6 min. The blood loss was 150 - 500 ml, mean 315 ml. The postoperative HSS and ROM were both reduced. The last follow-up, there were no meniscus subluxation, loose prosthesis, and lateral ventricular osteoarthritis or other complications. Conclusion: Unicompartmental knee arthroplasty has the advantages of small operation trauma, early postoperative effect and quick recovery.

Outcomes of mobile bearing unicompartmental knee arthroplasty in medial osteoarthritis knee with and without preoperative genu recurvatum

AIM To compare clinical outcomes of patients with and without preoperative genu recurvatum(GR) following mobile bearing unicompartmental knee arthroplasty(UKA). METHODS We prospectively followed 176 patients for at least 24 mo who had been treated by unilateral, minimally invasive, Oxford UKA. Patients with medial osteoarthritis(OA) knee and preoperative GR(Group Ⅰ) accounted for 18%(n = 32) and patients without preoperative GR(Group Ⅱ) accounted for the remaining 82%(n = 144). Knee score, pain scores, and functional scores were assessed for each patient and compared between the two groups. The incidence of postoperative GRand the postoperative hyperextension angles also were recorded and analyzed. RESULTS The pain score, knee score and functional score were not significantly different between the two groups. Similarly, the incidence of postoperative GR and the measured hyperextension angles were not significantly different between the two groups. The incidence of postoperative GR was 1/32(3.12%) in Group Ⅰ and 1/144(0.69%) in Group Ⅱ(P = 0.34). The mean postoperative hyperextension angles were 2.40°± 2.19°(range: 1°-7°) for Group Ⅰ and 1.57°± 3.51°(range: 1°-6°) for Group Ⅱ(P = 0.65).CONCLUSION Medial OA of the knee and concomitant GR is not a contraindication for the mobile bearing UKA.

Unicompartmental knee prosthetization: Which key-points to consider?

Unicompartmental knee arthroplasty(UKA) has evolved into a suitable option for diseased knees that cannot be managed with arthroscopic treatment and at the same time are not good candidates for total knee replacement. Since meticulous execution of the surgical technique is essential to optimizing UKA outcome, some procedural key-points are mandatory. Templates(phantoms) are then used to size the required prosthetic component(using these radiographs. Arthritic varus(or valgus) knees with an asymptomatic patellofemoral joint are typically ideal for UKA. Metal-backed tibial components should be favourite instead of allpolyethylene tibial components to avoid polyethylene creep that may occur in fixed bearings. Moreover, a proper thickness of the polyethylene layer is mandatory, in order to avoid early failure.

Lateral unicompartmental knee arthroplasty:A review

Isolated lateral compartment osteoarthritis of the knee is a rare condition affecting approximately 1%of the population,which is ten times less common than osteoarthritis affecting only the medial compartment.Unicompartmental knee arthroplasty(UKA)has many potential advantages over total knee arthroplasty.The benefits of UKA include a smaller incision,preservation of more native tissue(including cruciate ligaments and bone),decreased blood loss,and better overall proprioception.When UKA was first introduced in the 1970s,the outcomes of medial UKA(MUKA)were poor,but the few cases of lateral UKA(LUKA)showed promise.Since that time,there has been a relative paucity of literature focused specifically on LUKA given it is a rare procedure.Refinements in patient selection criteria,implant design,and surgical technique have been made leading to increased popularity.A review of the recent literature reveals that LUKA is associated with excellent long-term clinical outcomes and implant survivorship when performed in properly selected patients.Implant design options include fixed vs mobile bearing as well as metal backed vs all polyethylene tibial component,with improved outcomes noted with fixed bearing designs.Three reasons cited for revision(i.e.,fracture of the femoral component,fracture of the tibial component,and valgus malalignment)had been reported in past literature but not recently.Presently,while rare,the most common cause of failure and need for revision are osteoarthritis progression and aseptic loosening.Despite the need for an occasional revision procedure,the survivorship of LUKA is comparable to MUKA,although it should be noted that outcomes of MUKA have been notably varied.Continued pursuit of improved techniques and implant designs will continue to show LUKA to be an excellent procedure for appropriately indicated patients.

Unicompartmental Knee Arthroplasty: A Perspective from Computer Assisted Navigation

Unicompartmental Knee Arthroplasty (UKA) is an established procedure for the treatment of unicompartmental arthritis. Success depends on a clear understanding of the principles and kinematics of the knee. Restoration of the physiological axis and soft tissue balancing is the key to a successful outcome. We outline the basic principles of UKA and the role of computer assisted surgery in achieving these goals.

Determining the Effect of Deprivation on Quality of Life after Total and Unicompartmental Knee Arthroplasty

Determining the effect of deprivation on quality of life after total and unicompartmental knee arthroplasty Quality of life (QoL) following joint replacement is now a national priority, with every patient being assessed using the Oxford Knee Score. The current literature is conflicted as to whether deprivation has any effect on outcome after knee surgery. The type of surgery is another variable that may determine outcome. We set out to investigate which of these factors was a more powerful predictor of outcome. A prospective trial began where, 68 patients were telephoned, (30 TKA’s and 38 UKA’s). Each were asked a series of questions comprising the Oxford Knee Score (post operation), Imperial Knee Score (post operation), EuroQol-5D (pre and post operation) and individual deprivation questions. This was compared with the deprivation status using Townsend scores. A comparison of total and unicompartmental outcomes were also analysed including cost-effectiveness. No correlation was found between outcome and Townsend scores (p < 0.05). Age was seen to be a significant indicator of pre surgical QoL. However, a large and significant difference was found between UKA and TKA when using the EQ-5D (p < 0.05) and the Imperial Knee Score (p < 0.09). This was not reflected in the Oxford Knee Score. UKA’s were also found to be more cost-effective than TKA’s. Deprivation has no major effect on the outcome of knee surgery in London. A clear difference in efficacy exists between TKA’s and UKA’s. Sensitivity of scores needs to be addressed.

Internal fixation and unicompartmental knee arthroplasty for an elderly patient with patellar fracture and anteromedial osteoarthritis:A case report

BACKGROUND Open reduction and internal fixation(ORIF)is the traditional surgical treatment for patellar fractures,and unicompartmental knee arthroplasty(UKA),especially Oxford UKA,has been increasingly used in patients with medial knee osteoarthritis(OA).However,the process of choosing treatment for patients with both patellar fractures and anteromedial knee OA remains unclear.We present the case of a patient with a patellar fracture and anteromedial OA.CASE SUMMARY We present the case of a 72-year-old woman with a history of bilateral medial compartment OA of the knees and a right Oxford UKA.She also experienced a recent left patellar fracture.ORIF and Oxford UKA were performed in a single stage.The patient showed excellent postoperative clinical results.CONCLUSION ORIF and Oxford UKA can be performed simultaneously for patients with patellar fracture and anteromedial OA on the same knee.

<i>In vitro</i>measurement of tibiofemoral kinematics after patient-specific unicompartmental knee replacement

It is suggested that unicompartmental knee replacement (UKR) offers the potential to restore normal knee kinematics better than total knee replacement (TKR) because of retaining the cruciate ligaments, and better preservation of the overall geometry. It was hypothesized that patient-specific UKR would restore normal knee kinematics even better because of a customised articular shape. A comparative kinematics study was conducted on three cadaver limbs using two different test setups, a loaded ankle rig and an unloaded ankle rig. Kinematics was compared between a patient-specific UKR and a conventional fixed-bearing UKR. Both the UKRs showed similar kinematic patterns to the normal knee using both the test apparatus. The patient-specific UKR showed good results and with the other benefits it shows potential to dramatically improve clinical outcomes of knee replacement surgery.

Analysis of causes for revision in unicompartmental knee arthroplasty

The study by Zhao et al identifies the factors leading to the failure of unicompartmental knee arthroplasty(UKA)in their patients.These factors include substandard suturing of the wound,the presence of osteophytes and intra-articular loose bodies causing impingement,premature loosening of the tibial component,choosing unsuitable patients for the procedure,dislocation of the movable insert,and damage to the anterior cruciate ligament and medial collateral ligament.The findings suggest that employing the correct surgical techniques and indications is essential for successful outcomes in the UKA.

Insights into complications after unicompartmental knee arthroplasty

Zhao's study,offers a comprehensive analysis of unicompartmental knee arthroplasty(UKA)revision indications.The study provides a detailed,case-by-case analysis of the factors leading to knee revision surgery in 13 patients.Not only elucidates the complexities of UKA revisions but also underscores the importance of continuous improvement in surgical techniques and the adoption of innovative technologies.

Influence of patellofemoral joint degeneration on clinical outcomes after medial unicompartmental knee arthroplasty

Background:Patellofemoral joint(PFJ)degeneration has traditionally been regarded as a contraindication to unicompartmental knee arthroplasty(UKA).More recently,some researchers have proposed that PFJ degeneration can be ignored in medial UKA,and others have proposed that this change should be reviewed in PFJ degenerative facets and severity.This study aimed to systematically evaluate the effect of PFJ degeneration on patient-reported outcome measures(PROMs)and revision rates after medial UKA.Methods:Electronic databases(PubMed,Embase,Web of Science,etc.)were searched for studies assessing the influence of PFJ degeneration on medial UKA.A random-effects meta-analysis was conducted for the Oxford knee score(OKS),Knee society score(KSS),and revision rates and stratified by PFJ degenerative facets(medial/lateral/trochlear/unspecified),severe PFJ degeneration(bone exposed),and bearing type(mobile/fixed).Heterogeneity was assessed by the Cochran Q test statistic and chi-squared tests with the I-squared statistic.Results:A total of 34 articles with 7007 knees(2267 with PFJ degeneration)were included(5762 mobile-bearing and 1145 fixed-bearing and 100 unspecified).Slight to moderate degenerative changes in the medial and trochlear facets did not decrease the OKS and KSS,and only lateral facets significantly decreased the OKS(mean difference[MD]=-2.18,P<0.01)and KSS(MD=-2.61,P<0.01).The severity degree of PFJ degeneration had no additional adverse effect on the OKS,KSS,or revision rates.For mobile-bearing UKA,only lateral PFJ degeneration significantly decreased the OKS(MD=-2.21,P<0.01)and KSS(MD=-2.44,P<0.01).For fixed-bearing UKA,no correlation was found between PROMs/revision rates and PFJ degeneration.Conclusion:For medial mobile-bearing UKA,slight to moderate degenerative changes in the PFJ,except lateral facet,did not compromise PROMs or revision rates.For medial fixed-bearing UKA,although it might not be conclusive enough,PROMs or revision rates were not adversely affected by PFJ degeneration(regardless of the facet).

镜下前交叉韧带重建联合固定平台单髁置换术的早中期临床疗效观察

目的 探讨单髁置换手术(unicompartmental knee arthroplasty, UKA)联合前交叉韧带重建手术(anterior cruciate ligament reconstruction, ACLR)对单间室膝骨关节炎(unicompartmental knee osteoarthritis, UKOA)合并前交叉韧带缺失(anterior cruciate ligament deficient, ACLD)患者的早期临床疗效结果。方法 选取2018年1月至2022年6月广西中医药大学附属桂林市中医医院采用同期UKA联合ACLR治疗的UKOA合并ACLD的12例患者进行回顾性研究。评估术前和末次随访的VAS、IKDC、Lysholm评分,并随访观察并发症及翻修的发生情况。结果 所有患者随访6~55个月,平均随访(24.58±10.48)个月。所有患者的平均住院时间为(13.67±6.20)d,平均出血量为(43.33±39.44)mL,平均切口长度为(9.25±0.43)cm。末次随访时的VAS评分较术前明显降低(P<0.05);Lysholm评分平均为(67.17±22.96)分、IKDC评分平均为(59.87±8.77)分,分别较术前平均(51.33±14.99)分、(48.95±13.68)分明显提高(P<0.05)。结论 早中期的临床数据显示,同时进行ACLR联合UKA对UKOA合并ACLD手术治疗的临床疗效显著,可有效改善患者的膝关节不稳定和内侧间室疼痛,提高患者本体感觉,患者并发症发生率较低,值得临床推广应用,但应严格把握手术的适应证。

综合性干预对人工单髁膝关节置换患者术后关节功能恢复及满意度的影响

目的探讨综合性护理对人工单髁膝关节置换患者术后关节功能恢复和满意度的影响。方法选取2020年1月至2022年12月行人工单髁膝关节置换术的膝关节骨性关节炎患者60例,按照随机数字表法均分2组,每组30例。对照组予以常规护理,试验组予以综合性护理,对2组的护理成效进行对比分析。结果2组护理前的HSS评分无统计学意义(P>0.05),干预后试验组的HSS评分(92.83±3.47)分显著高于对照组的(80.93±3.28)分,2组比较差异有统计学意义(P<0.05),试验组术后在首次排气、首次排便、排便恢复至术前三方面的平均时间均短于对照组,差异有统计学意义(P<0.05),试验组和对照组的护理满意度分别为96.67%、73.33%,试验组高于对照组,差异有统计学意义(P<0.05),干预后试验组SF-36评分显著高于对照组(P<0.05)。结论对人工单髁膝关节置换术的患者实施综合性护理,能够明显改善患者的膝关节功能,促进胃肠道恢复,提高患者的护理满意度和生活质量,值得推荐。

复方倍他米松对坐骨神经联合股神经阻滞下膝关节单髁置换术后爆发痛的影响

目的探讨复方倍他米松对坐骨神经联合股神经阻滞下膝关节单髁置换术后爆发痛的影响。方法选择行单侧膝关节单髁置换术患者100例,男32例,女68例,年龄55~75岁,BMI 18.5~35.0 kg/m^(2),ASAⅠ—Ⅲ级。采用随机数字表法将患者分为三组:无佐剂组(C组,n=34)、地塞米松佐剂组(D组,n=33)和复方倍他米松佐剂组(B组,n=33)。麻醉诱导前三组行坐骨神经阻滞,注入0.4%罗哌卡因15 ml。之后再行股神经阻滞,C组注入0.4%罗哌卡因15 ml,D组注入0.4%罗哌卡因15 ml(含地塞米松5 mg),B组注入0.4%罗哌卡因15 ml(含复方倍他米松4 mg)。记录术后爆发痛发生情况、爆发痛评分、镇痛泵有效按压次数、阿片类药物用量和补救镇痛例数。记录术后0~24 h、24~48 h、48~72 h下地活动距离、睡眠质量评分以及不良事件发生情况。结果与C组比较,B组术后爆发痛发生率明显降低(P<0.05),镇痛泵有效按压次数、阿片类药物用量明显减少(P<0.05),补救镇痛率和术后第1晚睡眠质量评分明显降低(P<0.05)。与D组比较,B组术后爆发痛发生率和爆发痛评分明显降低(P<0.05),镇痛泵有效按压次数、阿片类药物用量明显减少(P<0.05),补救镇痛率和术后第1晚睡眠质量评分明显降低(P<0.05)。三组不同时间段下地活动距离、不良事件发生率差异无统计学意义。结论复方倍他米松佐剂可降低坐骨神经联合股神经阻滞下膝关节单髁置换术后爆发痛发生率,提供完善的镇痛效果,减少术后阿片类药物用量,提高患者术后第1晚睡眠质量。

单髁置换治疗膝关节内侧间室骨关节炎:关节功能及炎性细胞因子变化

背景:单髁置换因其创伤小、失血少、并发症少、康复快、膝关节功能优、假体生存率高等优点,越来越受到重视,相关报道多集中于其临床疗效,而单髁置换后患者体内相关炎性细胞因子的水平变化罕见报道。目的:探讨膝关节内侧间室骨关节炎患者单髁置换后的疗效及关节滑液白细胞介素1、白细胞介素6、肿瘤坏死因子α水平变化。方法:以2021年9月至2023年3月因膝内侧间室骨关节炎行单髁置换治疗并符合纳入标准的30例患者作为研究对象。比较术前、术后胫骨近端内侧角、股胫角、疼痛目测类比评分、美国特种外科医院膝关节评分、膝关节活动度及关节滑液白细胞介素1、白细胞介素6、肿瘤坏死因子α水平,并进行统计学分析。结果与结论:①30例患者术后切口均Ⅰ级愈合,术后均获6个月以上随访,所有患者均未出现假体松动、假体衬垫脱位等并发症;②术后1个月测量胫骨近端内侧角、股胫角均较术前明显改善(P<0.05);③术后1,3,6个月测量疼痛目测类比评分、美国特种外科医院膝关节评分、膝关节活动度均优于术前(P<0.05),术后各时间点呈逐渐好转趋势(P<0.05);④术后3,6个月测量关节滑液白细胞介素1、白细胞介素6、肿瘤坏死因子α水平均较术前逐渐下降(P<0.05),术后各时间点呈逐渐下降趋势;⑤提示单髁置换可有效治疗膝关节内侧间室骨关节炎,显著缓解患者疼痛,恢复膝关节功能,改善膝内翻畸形及下肢力线,并能在一定程度上降低关节内炎性细胞因子白细胞介素1、白细胞介素6、肿瘤坏死因子α的表达水平。

Finite Element Analysis of Mobile-bearing Unicompartmental Knee Arthroplasty： The Influence of Tibial Component Coronal Alignment

Background： Controversies about the rational positioning of the tibial component in unicompartmental knee arthroplasty （UKA） still exist. Previous finite element （FE） studies were rare, and the results varied. This FE study aimed to analyze the influence of the tibial component coronal alignment on knee biomechanics in mobile-bearing UKA and find a ration range of inclination angles. Methods： A three-dimensional FE model of the intact knee was constructed from image data of one normal subject. A 1000 N compressive load was applied to the intact knee model for validating. Then a set of eleven UKA FE models was developed with the coronal inclination angles of the tibial tray ranging from 10° valgus to 10° varus. Tibial bone stresses and strains, contact pressures and load distribution in all UKA models were calculated and analyzed under the unified loading and boundary conditions. Results： Load distribution, contact pressures, and contact areas in intact knee model were validated. In UKA models, von Mises stress and compressive strain at proximal medial cortical bone increased significantly as the tibial tray was in valgus inclination 〉4°, which may increase the risk of residual pain. Compressive strains at tibial keel slot were above the high threshold with varus inclination 〉4°, which may result in greater risk of component migration. Tibial bone resection comer acted as a strain-raiser regardless of the inclination angles. Compressive strains at the resected surface slightly changed with the varying inclinations and were not supposed to induce bone resorption and component loosening. Contact pressures and load percentage in lateral compartment increased with the more varus inclination, which may lead to osteoarthritis progression. Conclusions： Static knee biomechanics after UKA can be greatly affected by tibial component coronal alignment. A rauge from 4° valgus to 4° varus inclination oftibial component can be recommended in mobile-bearing UKA.

两种不同平台单髁置换术对内侧单间室膝骨性关节炎短期疗效比较

目的观察活动平台与固定平台单髁置换术对膝骨性关节炎手术治疗的短期疗效。方法选取内侧单间室膝骨关节炎患者155例,均行人工单髁置换术,其中97例选择美国邦美Oxford第三代活动平台(mobilebearing,MB)单髁假体,58例选择德国LINK固定平台(fixed-bearing,FB)单髁假体。比较两组手术时间及术中出血量;术前及术后1周、1个月视觉模拟评分(VAS);术前及术后1个月、3个月、6个月膝关节活动度(range of motion,ROM)及美国特种外科医院(hospital for special surgery,HSS)评分,并进行统计学分析。结果MB组与FB组手术时间及术中出血量比较差异均无统计学意义(P均>0.05)。术前、术后1周及术后1个月VAS评分差异均无统计学意义(P均>0.05),术前及术后1个月、3个月、6个月两组间ROM、HSS评分及术后6个月内并发症发病率差异均无统计学意义(P均>0.05)。结论MB和FB单髁置换术在膝骨性关节炎中短期疗效差异无统计学意义,MB单髁假体术后易出现假体脱位。

骨质疏松患者单髁置换过程中股骨假体置入位置优化的有限元分析

背景:骨质疏松患者行单髁置换过程中,股骨假体的合理置入范围尚未见研究,既往的相关研究常建立在正常骨质的单髁置换模型上,而对于非正常骨质模型的力学研究较少。单髁置换后的并发症已经被证实与骨质疏松高度相关。目的:采用有限元法分析Sled固定平台股骨假体冠状倾斜度对骨质疏松患者单髁置换后生物力学的影响,并且寻找骨质疏松与单髁置换后中远期并发症的相关性。方法:基于数字化影像技术获取膝关节和假体的数据,再通过Mimics、Geomagic studio等专用软件建立一个正常骨质膝关节模型。基于已验证的正常骨质膝关节模型,通过改变材料参数创建骨质疏松膝关节模型。以Sled固定平台股骨假体标准位置(0°)为基准,正常骨质组与骨质疏松组分别依次建立股骨假体内、外翻3°,6°,9°,共计14个单髁置换模型,计算并分析所有单髁置换模型中聚乙烯衬垫表面、胫骨假体下松质骨和皮质骨的应力变化。结果与结论:(1)在骨质疏松模型中,聚乙烯衬垫表面和胫骨假体下松质骨的高应力值随股骨假体倾斜角度的增加而增加,胫骨假体下皮质骨表面的高应力值随假体外翻角度的增加而增加,随内翻角度的增加而减小;(2)对于聚乙烯衬垫表面以及胫骨假体下皮质骨表面,骨质疏松组各倾斜角度模型的高应力值均大于正常骨质组中对应的模型;对于胫骨假体下松质骨表面,骨质疏松组各倾斜角度模型的高应力值均小于正常骨质组中对应的模型;(3)骨质疏松可能会引起单髁置换术后膝关节内部结构的生物力学异常,增加术后假体无菌性松动和假体周围骨折的潜在风险;骨质疏松性膝关节行Sled固定平台内侧单髁置换时应尽可能避免股骨假体在冠状面上内翻/外翻。

UKA假体后倾角安装位置对衬垫磨损的影响

目的研究单髁膝关节置换(unicompartmental knee arthroplasty,UKA)假体不同后倾角度安装对膝关节承载、运动及衬垫磨损的影响。方法联合UKA骨肌多体动力学模型、有限元模型和磨损模型,分析固定式UKA假体5种后倾角安装位置情况对术后膝关节力和运动、衬垫接触应力、线性磨损深度和体积磨损量的影响。结果后倾角0°时,衬垫的最大von Mises等效应力为24.84 MPa,接触应力为47.61 MPa,5百万次循环(million cycle,MC)周期的磨损量为47.29 mm3。随着UKA胫骨假体后倾角的增加,步态周期内旋和后移运动均增大,摆动相的内侧关节力增大,5 MC磨损周期后衬垫von Mises等效应力与接触应力显著减小,衬垫的磨损面积、最大线性磨损深度和体积磨损量随之减少。相对于后倾角0°,后倾角为3°、5°、7°时衬垫的线性磨损深度分别减小了17.8%、19.2%、20.6%;衬垫体积磨损量分别下降了24.5%、30.9%、34.3%。结论UKA假体考虑后倾角安装超过3°时会显著增加步态周期内旋运动和后移运动,减小聚乙烯衬垫关节面的磨损。