Arthroscopy of total knee arthroplasties: Indications and technical problems

Summary   Background: Postoperative complaints after total knee arthroplasty range from restriction in range of motion, recurrent swelling, and soft tissue impingement through to prosthesis failure with no obvious radiological abnormality. This study looks at the indications and technical problems of arthroscopy in the treatment of symptomatic total knee arthroplasty. Methods: Fourteen arthroscopies were performed between 3 days and 10 years following total knee arthroplasty. Six of these cases presented significantly decreased range of motion, four had proximal medial joint line pain, two had pain with no obvious cause, one had a suspected patella incongruence with metal-back contact, and one case had a postoperative haemarthrosis. Results: Arthroscopy revealed adhesions and intra-articular fibrous bands resulting in incongruence of the patellofemoral joint and decreased range of motion. Medial compartment pain was due to pseudomeniscal hypertrophic villous synovium. In one case, the pain was due to chronic infection and open synovectomy was undertaken. A fracture of the polyethylene inlet was found by arthroscopy in one case. The suspected patella malalignment with metal-back contact was confirmed by arthroscopy. Technical problems encompassed mirror images, the possibility of damaging the components by arthroscopic manipulation, and the variants of prosthesis. Conclusions: Arthroscopy of total knee arthroplasties is a good minimally invasive method for the diagnosis and treatment of postoperative dysfunction, such as arthrofibrosis, soft tissue impingement, patella instability, infection, breakdown of implants and haemarthrosis.      

混合型单髁与全膝关节置换治疗膝内侧间室骨关节炎的疗效比较

目的：探讨Oxford第3代混合型单髁置换（unicompartmental knee arthroplasty,UKA）与全膝关节置换（total knee arthroplasty,TKA）治疗膝关节内侧间室骨关节炎的疗效。方法：回顾性分析2017年10月至2019年10月行膝关节置换术的156例患者,男44例,女112例,年龄50~75（58.76±4.97）岁。根据不同治疗方式分为单侧TKA组和单侧Oxford第3代混合型UKA组。单侧TKA 81例（81膝）,男23例,女58例,年龄51~75（58.60±5.01）岁;单侧Oxford第3代混合型UKA 75例（75膝）,男21例,女54例,年龄50~72（58.92±4.95）岁。比较两组临床评估指标,包括手术一般情况、相关并发症、美国膝关节协会评分（American Knee Society score,AKSS）临床评分和功能评分;影像评估指标包括髋膝踝角（hip-knee-ankle angle,HKA）、股骨假体内外翻角（femoral component valgus/varus angle,FCVA）、股骨假体后倾角（femoral component posterior slope angle,FCPSA）、胫骨假体内外翻角（tibial component valgus/varus angle,TCVA）、胫骨假体后倾角（tibial component posterior slope angle,TCPSA）,是否发生膝关节外侧间室进展、衬垫脱位、假体下沉、松动。结果：UKA组术中出血量、手术时间、住院天数均显著优于TKA组（P<0.05）,两组术后均未出现并发症。两组患者均获随访,时间24~54（38.01±8.90）个月。末次随访两组AKSS临床评分、功能评分、HKA均优于术前（P<0.05）。末次随访UKA组AKSS临床评分、功能评分均优于TKA组（P<0.05）,TKA组HKA优于UKA组（P<0.05）。末次随访两组TCVA、FCVA差异无统计学意义（P>0.05）,UKA组TCPSA、FCPSA大于TKA组（P<0.05）,UKA组未出现外侧室进展。结论：Oxford第3代混合型UKA治疗膝关节内侧间室骨关节炎,较TKA具有手术创伤小、失血量少、手术时间短、住院时间短、术后快速康复、膝关节功能恢复更好等优势,疗效满意。     

Distal femoral cut perpendicular to the mechanical axis may induce varus instability in flexion in medial osteoarthritic knees with varus deformity in total knee arthroplasty: a pitfall of the navigation system

Two factors that influence the external rotation angle of the femoral rotational axis in total knee arthroplasty (TKA) were assessed in 40 medial osteoarthritic knees with varus deformity. First, the anatomic configuration of the femur was assessed using standardized radiographs of the patients lower extremities before TKA. Second, the degree of medial soft tissue release was assessed during TKA. The radiographs showed that the characteristics of the femur were lateral bowing of the shaft and external rotation of the condyle in the coronal plane. Therefore, when the distal femur is cut perpendicular to the mechanical axis, the cut surface may be in too much of a valgus position. Furthermore, some degree of medial soft tissue release was necessary in all knees. Medial soft tissue release rotates the femur externally in extension in the coronal plane, and it rotates the femur externally around the femoral axis in flexion relative to the tibia. A distal femoral cut in too much of a valgus position and medial soft tissue release induces varus instability in flexion in knees with lateral bowing of the femoral shaft. Anatomic variation such as femoral bowing should be considered when a navigation system is used for TKA because the navigation system shows only the mechanical axis.     

Navigated Unicompartmental Knee Arthroplasty: A Different Perspective

BackgroudAnteromedial osteoarthritis is a recognized indication for unicompartmental knee arthroplasty (UKA). Favorable postoperative outcomes largely depend on proper patient selection, correct implant positioning, and limb alignment. Computer navigation has a proven value over conventional systems in reducing mechanical errors in total knee arthroplasty (TKA). However, the lack of strong evidence impedes the universal use of computer navigation technology in UKA. Therefore, this study was proposed to investigate the accuracy of component positioning and limb alignment in computer navigated UKA and to observe the role of navigation in proper patient selection.MethodsA total of 50 knees (38 patients) underwent computer navigated UKA between 2016 and 2018. All operations were performed by the senior surgeon using the same navigation system and implant type. The navigation system was used as a tool to aid patient selection: knees with preoperative residual varus > 5° on valgus stress and hyperextension > 10° were switched to navigated TKA. We measured the accuracy of component placement in sagittal and coronal planes on postoperative radiographs. Functional outcomes were also evaluated at the final follow-up (a minimum of 16 months).ResultsNine patients had tibia vara and 14 patients had preoperative hyperextension deformity. We observed coronal outliers for the tibial component in 12% knees and for the femoral component in 10% knees. We also observed sagittal outliers for the tibial component in 14% knees and for the femoral component in 6% knees. There was a significant improvement in the functional score at the final follow-up. On multiple linear regression, no difference was found in functional scores of knees with or without tibia vara (p = 0.16) and with or without hyperextension (p = 0.25).ConclusionsOur study further validates the role of computer navigation in desirable implant positioning and limb alignment. We encourage use of computer-assisted navigation as a tool for patient selection, as it allows intraoperative dynamic goniometry and provides real-time kinematic behavior of the knee to obviate pitfalls such as significant residual varus angulation and hyperextension that predispose early failure of UKA.     

一种新型计算机辅助全膝关节置换手术系统：华佗（WATO）

目的评估计算机辅助骨科手术（CAOS）系统——华佗（WATO）系统的操作精度，并进行临床应用前的检测，为系统改进和临床使用提供实验依据。方法本研究包括假骨切割和尸体膝关节切割两部分，实验组使用WATO系统作为术前规划和股骨、胫骨的定位工具，根据定位过程中确定的参考力线，驱动机器人做精确的截骨；对照组由高年资关节外科医生使用常规手术工具进行截骨。截骨结束后比较测量力线和规划的理想下肢力线的偏角，并进行统计学分析。结果实验组使用WATO系统切割了200根假骨，平均偏角为0．98°±1．17°（0°～5．3°），对照组使用标准全膝关节置换工具切割了30根假骨，平均偏角为2．09°±1．96°（0．1°～7．1°）。两者平均偏角比较差异有统计学意义（P〈0．01）。实验组使用WATO系统进行5具尸体膝关节的截骨，平均偏角为1．44°±0．52°（0．9°～2．3°），对照组使用标准全膝关节置换工具进行5具尸体膝关节的截骨，平均偏角为4．38°±2．72°（1.1°～7．9°）。两者平均偏角比较差异有统计学意义（P〈0．05）。结论WATO系统与传统全膝关节置换术相比具有良好的准确性和稳定性，有望在将来的临床使用中辅助关节外科医生实现更好的术后力线重建。     

地塞米松用于全膝关节置换术中关节周围浸润镇痛的临床研究

目的探讨全膝关节置换(TKA)术中关节周围注射的镇痛混合药物中添加小剂量地塞米松对改善患者术后疼痛的有效性及安全性。方法纳入自2014-12—2015-02行TKA的40例单侧膝关节骨性关节炎,随机分为试验组和对照组,每组20例。试验组75 ml生理盐水混合液包含150 mg罗哌卡因、肾上腺素0.1 ml、地塞米松5 mg;对照组不含地塞米松。结果试验组手术时间为(86.3±2.7)min,对照组为(85.5±2.8)min,差异无统计学意义(t=0.212,P=0.836)。试验组与对照组术后6、12、24、48 h的VAS评分比较差异无统计学意义(P0.05)。试验组1例出现切口中部皮肤坏死,切除坏死皮肤减张缝合后2周拆线,切口愈合。对照组切口均愈合良好,未出现并发症。2组切口并发症发生率比较差异无统计学意义(χ2=0.026,P=0.500)。结论 TKA术中关节周围注射的镇痛混合药物中添加地塞米松并未增加术后切口感染等并发症的发生,但是也无额外改善术后急性期疼痛的效用,因此临床上不建议添加。     

Surgical accuracy and clinical outcomes of image-free robotic-assisted total knee arthroplasty

Background

The development of total knee arthroplasty (TKA) for knee osteoarthritis (OA) has a good reputation for its effectiveness in reducing joint pain and improving range of motion. We aimed to review our early results using the image-free robotic-assisted technology in knee arthroplasty.

Methods

A total of 71 patients suffering from end-stage OA knee receiving TKA operated by robotic-assisted surgery between the years 2018 and mid-2021 were recruited. Clinical and radiological outcomes were compared with age and sex-matched control group (conventional TKA).

Results

The radiological outcome showed significantly more postoperative lower limb alignment outliers in conventional side than robotic-assisted sides. Postoperative knee scores were similar among both groups. Robotic-assisted TKA required a longer implantation time but a shorter hospital stay.

Conclusion

Robotic-assisted TKA achieved a lower rate of mechanical axis Outlier in the coronal and sagittal plane with a shorter hospital stay. Yet both methods achieve a similar functional outcome.     

Muscle force and movement variability before and after total knee arthroplasty: A review

Variability in muscle force output and movement variability are important aspects of identifying individuals with mobility deficits, central nervous system impairments, and future risk of falling. This has been investigated in elderly healthy and impaired adults, as well as in adults with osteoarthritis (OA), but the question of whether the same correlations also apply to those who have undergone a surgical intervention such as total knee arthroplasty (TKA) is still being investigated. While there is a growing body of literature identifying potential rehabilitation targets for individuals who have undergone TKA, it is important to first understand the underlying post-operative impairments to more efficiently target functional deficits that may lead to improved long-term outcomes. The purpose of this article is to review the potential role of muscle force output and movement variability in TKA recipients. The narrative review relies on existing literature in elderly healthy and impaired individuals, as well as in those with OA before and following TKA. The variables that may predict long-term functional abilities and deficits are discussed in the context of existing literature in healthy older adults and older adults with OA and following TKA, as well as the role future research in this field may play in providing evidence-based data for improved rehabilitation targets.     

A systematic review of the effects of platelet rich plasma on outcomes for patients with knee osteoarthritis and following total knee arthroplasty

Introduction

Platelet rich plasma (PRP) has been suggested to be effective in the management of knee osteoarthritis. Review of current literature reveals conflicting evidence regarding the benefits of PRP in treating knee OA. Preclinical evidence supports the use of PRP injections to promote a favorable environment for joint tissue healing, targeting not only cartilage but also synovial and meniscal tissues which has a positive effect on delaying the progression of OA. Growth factors found in platelet granules are postulated to influence outcomes in knee OA and after total knee arthroplasty (TKA).

滑膜切除对全膝关节置换术治疗骨性关节炎临床效果的影响

目的探讨滑膜切除对全膝关节置换术治疗骨性关节炎临床效果的影响。方法回顾性分析自2011-07—2014-12诊治的105例膝关节骨性关节炎,分为试验组和对照组,试验组(56例)行膝关节置换术与滑膜切除术,对照组(49例)只行膝关节置换术。记录并比较2组手术时间、术后引流量、隐性失血量、输血率及住院时间等,术前和术后随访时进行VAS评分、KSS评分及测量关节活动度。结果试验组获得随访(17.0±4.2)个月,对照组获得随访(15.0±3.1)个月。试验组手术时间、隐性失血量、术后引流量较对照组多,差异均有统计学意义(P0.05),2组住院时间及输血率差异无统计学意义(P0.05)。2组术后4周及1年随访时VAS评分、KSS临床评分、KSS功能评分差异无统计学意义(P0.05)。2组术后3 d及术后7 d关节活动度比较差异无统计学意义(P0.05)。结论与单纯行膝关节置换术相比,膝关节置换同时行滑膜切除术在治疗骨性关节炎上无优势,然而行滑膜切除术会导致更多的体内失血,延长手术时间,从而增加了手术风险。     

标准型和形态特异型假体全膝关节置换术早期临床疗效比较分析

目的 通过对美国膝关节协会评分(KSS)、关节活动度(ROM)的分析,探讨全膝关节置换术中使用标准型和形态特异型假体的早期临床结果差异.方法 以2012年2月至2012年8月接受美国Wright医疗技术公司Advance系列膝关节假体置换术的39例(45膝)骨关节炎患者为研究对象,其中男性5例(6膝),女性34例(39膝).根据术中使用假体的设计类型分为两组:19例(21膝)接受形态特异型假体(Stature假体组),20例(24膝)接受标准型假体(MP假体组).假体类型选择依据:如果术中股骨髁远端或滑车区域出现假体突出,选用形态特异型假体,否则选用标准型假体.结果 总体样本中Stature假体使用率为46.7％(21膝∶45膝).Stature假体组和MP假体组平均随访时间分别为7.4个月和6.7个月,均未出现膝前疼痛、关节感染、下肢深静脉血栓、假体周围骨折等并发症.末次随访时,两组KSS分别为平均176.9±12.64分和174.4±13.87分,ROM分别为平均122.9°±10.30°和119.7°±7.60°;KSS平均改善值分别为98.60±24.98分和95.47±22.85分,ROM平均改善值分别为14.74°±10.18°和12.62°±9.57°,组间均无显著性差异(P＞0.05).结论 与标准MP假体相比,Stature假体有助于提高骨骼-假体匹配性及改善假体边缘突出现象,尤其是在中国女性患者,但并未提供更好的临床结果.     

Arthroscopy of the painful dysfunctional total knee replacement

Arthroscopy of the painful failed total knee arthroplasty has rarely been reported. The indications and results in terms of diagnosis and treatment of pathologic conditions in 13 knees after total knee arthroplasty are reviewed. Arthroscopy established the diagnosis for pain in 12 of 13 knees. Several problems were commonly encountered, including arthrofibrosis and fracture of the polyethylene button. Arthroscopic surgery for arthrofibrosis was successful in improving range of motion and knee-rating score.     

Tibial stress fracture after computer-navigated total knee arthroplasty

A correct alignment of the tibial and femoral component is one of the most important factors determining favourable long-term results of a total knee arthroplasty (TKA). The accuracy provided by the use of the computer navigation systems has been widely described in the literature so that their use has become increasingly popular in recent years; however, unpredictable complications, such as displaced or stress femoral or tibial fractures, have been reported to occur a few weeks after the operation. We present a case of a stress tibial fracture that occurred after a TKA performed with the use of a computer navigation system. The stress fracture, which eventually healed without further complications, occurred at one of the pinhole sites used for the placement of the tibial trackers.     

Bilateral staged total knee arthroplasty in obese patients

Introduction The purpose of this study was to compare the clinical and functional results and complications associated with staged bilateral total knee arthroplasty (TKA) performed 4–11 days apart during a single hospitalization in patients who were obese and patients who were not obese. Methods We retrospectively evaluated 48 (96 knees) patients who were obese and divided into two groups based on their body mass indices (BMI). Morbidly obese patients (group A1, BMI ≥ 40 kg/m²) consisted of 21 patients (42 knees), and obese patients (group A2, BMI ≥ 30 kg/m²) consisted of 27 patients (54 knees). The control group (group B, BMI < 30 kg/m²) consisted of 20 non-obese patients (40 knees), who were undergoing staged bilateral procedure within the same time frame. All patients had cemented TKAs with use of posterior cruciate sparing prosthesis without patellar resurfacing. If medically stable after the first arthroplasty the patients then underwent the second arthroplasty 4–11 days later. The data on major complications and minor complications were evaluated. Results Although, there was no statistically significant difference in overall complication rates in any of the groups, the non-obese group had fewer wound complications than the other groups (P > 0.05). No significant differences in preoperative or postoperative Knee Society score, and functional score could be demonstrated between the three groups (P > 0.05). Both obese and nonobese patients showed improvements in pain and function from pre-surgery to a minimum 2 years follow-up. Conclusion Results of bilateral staged TKAs in obese patients have low complication and high success rates and increased BMI has no negative effect on the early outcome. Bilateral staged TKA might be a good treatment alternative for the improvement of the patient’s quality of life and functional and clinical outcomes.     

骨性关节炎患者人工膝关节假体旋转定位标志研究

目的探讨对合并内、外翻畸形的膝关节骨性关节炎行人工全膝关节置换术，以股骨内外上髁外科轴（surgical epicondylar axis，SEA）作为股骨假体旋转参考轴，以胫骨结节内1／3作为胫骨假体旋转定位的骨性标志，判断股骨假体和胫骨假体的旋转对线情况。方法2004年7月～2005年1月，对32例（62膝）拟行人工全膝关节置换术的膝关节骨性关节炎患者（病例组），男2例，女30例；年龄58～80岁，平均68．9岁；内翻畸形55膝，胫股角平均内翻-8．23°；外翻畸形7膝，胫股角平均外翻＋15．48°。于术前行伸膝旋转中立位CT扫描，测量膝关节股骨后髁角（posterior condylar angle，PCA），并以10个正常膝关节作为对照组，测量SEA中点C与髌腱内1／3连线（BC）和经SEA中点C的垂线（AC）之间的夹角，即α角。结果病例组80％以上膝关节CT图像显示股骨内上髁陷凹；PCA中位数为＋2．36°（0～＋7．5°）；对照组膝关节α角为＋6．45±3．68°（0～＋11．8°）；病例组内翻畸形患者膝关节α角为＋10．85±10．47°（0～＋28．1°），与对照组比较差异有统计学意义（P〈0．05），病例组外翻畸形患者膝关节α角为＋11．6±7．3°（-6．5～＋26．8°），与对照组比较差异有统计学意义（P〈0．05）。结论以胫骨结节内1／3作为胫骨假体旋转参考轴线，胫骨假体相对于股骨假体处于轻度外旋位；合并内、外翻畸形患者的胫骨假体外旋角度明显增大，容易使股骨假体和胫骨假体间出现旋转对线不良。     

Accelerometer-based,hand-held navigation for improved knee alignment in total knee arthroplasty: An observational study

BackgroundMalalignment in total knee arthroplasty has been associated with poor implant longevity and clinical outcomes. The aim of this study was to investigate the accuracy of accelerometer-based navigation in restoring the mechanical axis.Methods106 primary total knee arthroplasties performed during February 2016 to September 2017 at a tertiary care centre in India were enrolled in this observational study. We noted the intra-op tourniquet time. Two separate blinded observers measured the preoperative mechanical axis and the post operative radiological results (mechanical axis, coronal and sagittal alignment of femoral and tibial components) and the mean value was taken as final data. Interclass correlation was done to look for variability between the two observers.ResultsThe mean pre operative mechanical axis was 13.74 ± 10.44. The mean tourniquet time was 53.14 ± 7.42 min 91.5% (96/106) knees were within ±3° of neutral mechanical axis with a mean of 1.00° ± 2.68°. The femoral and tibial components with coronal alignment within ±3° perpendicular to the mechanical axis were 93.39% (99/106) and 89.62% (95/106) respectively. In the sagittal plane 89.62% of the femoral components and 87.73% of the tibial components were within ±3° perpendicular to the axis of tibia.ConclusionThe Accelerometer based portable navigation system effectively reduces the coronal and sagittal alignment outliers in total knee arthroplasty and has no role in rotational alignment of components.     

Knee Scores of Patients with Non‐Lateral Compartmental Knee Osteoarthritis Undergoing Mobile,Fixed‐Bearing Unicompartmental Knee and Total Knee Arthroplasties: A Randomized Controlled Trial

ObjectiveTo evaluate knee scores and clinical efficacies of patients with non‐lateral unicompartmental knee osteoarthritis (OA) who randomly underwent mobile‐bearing (MB) unicompartmental knee arthroplasty (UKA), fixed‐bearing (FB) UKA, and total knee arthroplasty (TKA).MethodsFrom September 2015 to February 2017, a prospective, randomized, parallel, single‐center trial of 180 patients (78 males and 102 females; 63.3 ± 6.9 years) with non‐lateral compartmental knee OA was performed in the first author‐affiliated hospital. The patients were randomly divided into three groups (each group included 60 patients) and received medial cemented Oxford phase 3 MB UKA, medial cemented Link FB UKA, or cemented DePuy Sigma PFC TKA, respectively. A similar perioperative management and fast‐track surgery program was carried out for all patients. The knee scores at 3‐year follow‐up after operation and clinical efficacies of these three groups of patients were recorded, investigated, and compared.ResultsPrimarily, compared to the TKA group, the UKA groups (MB UKA and FB UKA) had shorter operative time (median 63.2 < 67.1 min), less bleeding (8.6 < 30.0 mL), earlier resumption of walking without crutches (3.0 < 8.0 days) and walking up and down the stairs (5.0 < 10.0 days) (P < 0.001), higher FJS scores (78.0 > 74.5) (P = 0.007), better results in all knee scores (except VAS and KSS function scores) (P < 0.05), and a larger maximum flexion angle of the knee at the 3‐year follow‐up (123.0° > 96.0°) (P = 0.001). Secondarily, compared to the TKA group, the MB UKA group showed better results in the Western Ontario and McMaster Universities index (WOMAC) stiffness (83.6 > 79.6), WOMAC total (86.3 > 83.2), Oxford knee score (OKS) (20.0 < 23.0), Forgotten Joint Score (FJS) (78.5 > 74.5), and a larger maximum flexion angle of the knee (123.0 > 96.0) (P < 0.05). Moreover, the FB UKA group showed higher Hospital for Special Surgery Knee Score (HSS) (91.0 > 88.5), WOMAC stiffness (84.3 > 79.6), WOMAC function (85.2 > 81.7), WOMAC total scores (87.6 > 83.2), and a larger maximum flexion angle of the knee (119.0° > 96.0°) than the TKA group (P < 0.05). Overall, there was no significant difference in all knee scores and maximum flexion angles of the knee for the MB UKA and FB UKA groups (P > 0.05). There was one case with original bearing dislocation in MB UKA group. One patient with displacement of the femoral component caused by a fall injury, and another patient, who lost his life in a car accident, were involved in the FB UKA group. There was an infection case and an intermuscular vein thrombosis case in TKA group.ConclusionUKA showed more advantages than TKA; however, there was no significant difference between the MB UKA and FB UKA groups for treatment of non‐lateral compartmental knee OA.     

3D打印个性化导航模板在全膝关节置换术中的应用

目的探讨3D打印个性化导航模板在全膝关节置换术中应用的临床效果。方法笔者自2014-03—2015-03对48例(70膝)行全膝关节置换术,随机分为导航模板组(利用个性化导航模板在术中辅助操作)和对照组(采用传统膝关节置换术),导航模板组术前采集CT扫描数据,设计个体化导航模板,并通过3D打印机进行制作。比较2组术前、术后血红蛋白(Hb)、血沉(ESR)及C反应蛋白(CRP)、手术时间、术中失血量、术后引流量。术后影像学测量股骨和胫骨机械轴的夹角(a MFTA)、股骨远端机械轴外侧角(a LDFA)、胫骨近端机械轴内侧角(a MPTA)和胫骨近端解剖轴后方角(m PPTA)。结果所有患者术后均获随访6~12个月,平均10个月,切口均一期愈合。2组术前术后HSS评分差异均有统计学意义(P0.01);术后导航模板组较对照组患者满意度均有提高,差异有统计学意义(P0.01)。术后第2天导航模板组血Hb值高于对照组,CRP值低于对照组,差异均有统计学意义(P0.01),2组ESR指标比较差异无统计学意义(P0.05)。2组术前术后Hb、ESR、CRP比较差异均有统计学意义(P0.01)。导航模板组手术时间、术中失血量及术后引流量均少于对照组,差异均有统计学意义(P0.01)。影像学测量结果显示导航模板组和对照组术后的a MFTA、a PPTA比较,差异均有统计学意义(P0.01)。结论全膝关节置换术中应用3D打印个性化导航模板,可以取得更好的临床疗效。