The influence of continuous passive motion on outcome in total knee arthroplasty

All primary condylar total knee replacement arthroplasties (TKAs) performed from 1977 to 1984 at the authors' institution were divided into two groups based on the use of continuous passive motion (CPM) in the immediate postoperative period. The control group consisted of 73 patients who were treated with 95 TKAs without postoperative CPM. The average age was 65.4 years. The study group consisted of 38 patients who had 51 TKAs in which CPM was used postoperatively. The mean patient age was 62.8 years. The most common diagnoses in both groups were osteoarthritis and rheumatoid arthritis. Range of motion (ROM) was recorded preoperatively, at discharge, at three months, one year, two years, and at the last follow-up visit. There were no statistically significant differences in the ROM between the two groups at any of these time periods. At two years, the mean flexion and extension in the study group were 99 degrees and -4 degrees, respectively, compared to 103 degrees and -5 degrees in the control group. The average hospital stay was 11.2 days in the study group, whereas it was 15.1 days in control group. In the control group, there was one superficial infection, no deep infections, and four pulmonary emboli compared with three superficial infections, two deep infections, and no pulmonary emboli in the study group. There was no difference in the transfusion requirements between the two groups. CPM is advocated by the authors to help achieve discharge ROM earlier, but the protocol has been changed to begin CPM on the second postoperative day to allow the wound to stabilize.     

术前活动度对人工全膝关节置换术后功能影响的观察

目的回顾性分析患者手术前的活动度对人工全膝关节置换(TKA)术后功能的影响。方法随访2000年1月—2003年12月在我科行TKA的患者65例(97膝),年龄64．8±9．9岁(35～85岁)。其中骨性关节炎55例(81膝),类风湿关节炎10例(16膝)。单膝置换33例,双膝同时置换32例。所有患者按术前膝关节活动度数(ROM)分成两组,≤90°(5°～90°)49膝,>90°(95°～140°)48膝。对两组患者进行疗效(最大屈膝度、活动度、KSS评分及功能评分)对比。所有患者均采用Scorpio后稳定型骨水泥固定的假体,均为初期置换,全部手术由同一组医师完成。术后3 d在同一康复师指导下行患肢CPM及主动功能锻炼至出院。结果平均随访时间29个月(10～44个月)。所有膝关节的活动度从术前的平均84．2°(5°～140°)提高到术后的平均101．6°(40°～140°) (P=0．000);而最大屈膝度数术前的平均103．5°(25°～140°)与术后的平均101．6°(40°～140°)无显著差异(P=0．439);KSS膝关节评分从术前平均19．5分(-24～62分)提高到术后平均78．8分(50～95分)(P=0．000)。所有患者的总满意度为93．8％(61／65)。两个分组比较,ROM≤90°的膝关节ROM及最大屈膝度术后均较术前有提高,而ROM>90°的膝关节平均最大屈膝度术后反而下降。没有翻修及深部感染。结论(1)在影响TKA术后膝关节功能的多种因素中,手术技术是关键因素。(2)在其他因素相同的情况下,术前膝关节的活动度对TKA术后的功能也有很大的影响,术前活动度大的膝关节比那些术前活动度小的膝关节术后能获得更好的功能。     

Continuous passive motion after total knee arthroplasty

Sixty-two patients undergoing primary total knee arthroplasty were studied prospectively. There were 42 patients in whom continuous passive motion (CPM) was used after surgery and 20 controls. The two groups were comparable with respect to age, diagnosis, sex, weight, and preoperative deformity and motion. The mean length of time required for CPM patients to achieve 90 degrees of flexion (9.1 days) was shorter than that for the control group (13.8 days). At the time of discharge from the hospital, however, there was no significant difference between the groups in amount of either flexion or extension. All patients had venograms performed after arthroplasty; the incidence of positive studies indicating thrombophlebitis was 45% in CPM patients and 75% in controls. These data demonstrate that CPM after knee arthroplasty enables patients to recover motion more quickly and affords some protection against deep vein thrombosis.     

Home continuous passive motion machine versus professional physical therapy following total knee replacement

A vigorous rehabilitation program following discharge from the hospital is necessary for patients having a total knee arthroplasty to maintain and improve range of motion and function. To compare the effectiveness of the continuous passive motion (CPM) machine as a home therapy program versus professional physical therapy, a prospective, comparative, randomized clinical study of 103 consecutive primary total knee arthroplasties in 80 patients (23 bilateral) was performed. The CPM group consisted of 37 patients (49 knees), and the physical therapy group consisted of 43 patients (54 knees). At 2 weeks, knee flexion was similar in the two groups, but a flexion contracture was noted in the CPM group (4.2°). This difference is felt by the authors to be clinically insignificant. At 6 months, there were no differences in knee scores, knee flexion, presence of flexion contracture, or extensor lag between the two groups. The cost for the CPM machine group was $10,582 ($286 per patient), and the cost for professional therapy was $23,994 ($558 per patient). We conclude that the CPM machine after the hospital discharge of patients having total knee replacement is an adequate rehabilitation alternative with lower cost and with no difference in results compared with professional therapy.     

Total condylar knee replacement. A study of factors influencing range of motion as late as two years after arthroplasty

The factors influencing the range of motion of the knee after total condylar knee replacement were analyzed in fifty-five consecutive patients who had seventy-one replacements and a minimum follow-up of two years. Statistically significant improvement in flexion occurred between the first postoperative evaluation in the hospital, the evaluation at discharge, and the evaluations at three months and one year after replacement. Postoperative range of motion was not influenced by the patient's gender, by the extent of the disease (monoarticular in comparison with polyarticular), or by treatment with a unilateral or bilateral procedure. The knees of patients with rheumatoid arthritis gained extension at the expense of flexion. The average flexion arcs of the knees with rheumatoid arthritis and of those with osteoarthritis were the same two years after operation as they had been preoperatively. Knees with preoperative flexion of more than 100 degrees had lost flexion at follow-up, whereas those with preoperative flexion of less than 100 degrees had gained flexion. Significant improvement in extension occurred only before discharge. For the patients whose preoperative flexion contracture was 10 degrees or more, virtually all improvement in the contracture occurred at the time of surgery. Patients who had a simultaneous bilateral total knee replacement did as well as those with a single knee replacement.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of adjunctive range-of-motion therapy after primary total knee arthroplasty on the use of health services after hospital discharge.

INTRODUCTION: There is controversy as to whether continuous passive motion (CPM) after total knee arthroplasty (TKA), which is the standard treatment, confers significant benefit with respect to outcome. The primary purpose of this study was to determine if CPM or slider-board (SB) therapy, used as adjuncts to standardized exercises (SEs) during the acute-care hospital stay, resulted in a reduced total length of hospitalization and post-discharge rehabilitation in patients who underwent primary TKA. METHODS: We carried out a randomized, clinical trial on 120 patients who received a TKA at the University of Alberta Hospital, Edmonton, a tertiary care institution. The study horizon began at the point of discharge from the hospital and continued up to 6 months after operation. Postoperatively, patients (40 in each group) received CPM and SEs, SB therapy and SEs or SEs alone while in the tertiary Health service use was compared using transfer institution length of stay(LOS), post-discharge rehabilitation, readmission and complication rates and their associated costs. RESULTS: There were no differences in health service use or costs among the 3 groups over the 6-month study. The rates of postoperative complications and readmissions also were similar among the groups. Increased health service use associated with knee flexion that was less than 60 degrees at discharge, but similar proportions of patients with poor knee range of movement (ROM) at discharge were found in each group. CONCLUSIONS: This finding suggests that adjunctive ROM therapy, as used in this study, does not reduce health service use. Further research is required to determine if adjunctive ROM therapy after discharge from the surgical hospital decreases health service utilization in those patients who have poor knee ROM at the time of discharge.     

Influence of hip position on knee flexion angle in patients undergoing total knee arthroplasty

The influence of hip position on knee flexion angle before total knee arthroplasty (TKA) and that after TKA were investigated and compared. Sixty-six patients (70 knees) with osteoarthritis who were undergoing TKA were examined using lateral radiographs of maximum knee flexion angle with the hip joint at 0 degrees extension and 90 degrees flexion. The postoperative rate of decrease in knee flexion angle caused by hip extension was significantly larger compared with the value before surgery. The preoperative rate of decrease in knee flexion angle caused by hip extension showed strong inverse correlation with the preoperative and postoperative knee flexion angle ratio. In conclusion, tightness of the extensor mechanism is present in all knees undergoing TKA and especially has a strong influence on the postoperative flexion angle of the knee.     

Beneficial effects of continuous passive motion after total condylar knee arthroplasty.

A randomised, controlled study of the use of postoperative continuous passive motion (CPM) and immobilisation regimen after total condylar knee arthroplasty was performed. CPM resulted in a significant increase in both the early and late range of knee flexion. This increase occurred in both rheumatoid and osteoarthritic patients. The improvement of 10 degrees at 12 months allowed additional important function to be attained. CPM resulted in significantly earlier discharge from hospital. It did not increase the clinical incidence of wound healing problems, nor did it significantly increase the postoperative fixed flexion deformity or the extension lag. CPM can be recommended as a safe and effective modality to achieve more rapid and more successful postoperative rehabilitation after knee arthroplasty.     

Continuous passive motion compared to active physical therapy after knee arthroplast:Similar hospitalization times in a randomized study of 68 patients

68 consecutive patients who had primary knee arthroplasties because of arthrosis were randomized to postoperative continuous passive motion (CPM) or active physical therapy (APT). Rehabilitation in both groups was initiated on the first postoperative day. The CPM group sustained less postoperative knee swelling with more rapid initial improvement in knee flexion than did the APT group, but there were no differences between the groups in knee flexion at discharge. Postoperative pain rating and hospitalization times were similar in the two groups.     

A comparison of 2 continuous passive motion protocols after total knee arthroplasty: a controlled and randomized study

Effect of continuous passive motion (CPM) protocols on outcomes after total knee arthroplasty. In this prospective randomized controlled study, 147 patients were assigned to 1 of 3 treatment groups: CPM from 0 degrees to 40 degrees and increased by 10 degrees per day, CPM from 90 degrees to 50 degrees (early flexion) and gradually progressed into full extension over a 3-day period, and a no-CPM group. The CPM was administered twice a day for 3 hours over a 5-day period. All patients participated in the same postoperative physiotherapy program. Patients were assessed preoperatively, day 5, 3 months, and 1 year postoperatively. The early flexion group had significantly more range of flexion than both the standard and control groups at day 5. There was no significant difference between the groups for any other variable tested at any time frame. Key words: total knee arthroplasty, CPM, rehabilitation, outcomes.     

The Efficacy of Continuous Passive Motion After Total Knee Arthroplasty: A Comparison of Three Protocols

We conducted a randomized, controlled trial to determine the efficacy of CPM following total knee arthroplasty (TKA). Postoperative outcomes of interest were: swelling, drop in hemoglobin, self-reported pain scores, range of motion, and hospital length of stay. A total of 160 subjects were randomized into one of three treatment groups: CPM device on and moving from the immediate post-operative period, CPM device on and stationary at 90 degree flexion for the first night and then moving throughout the rest of their stay, and no CPM (N = 55, 51, and 54, respectfully). Subjects were followed during the first and second postoperative day until their first follow-up appointment approximately 3–4 weeks post-operatively. Cost of CPM was further evaluated. CPM provided no benefit to patients recovering from TKA.     

Posterior condylar offset and flexion in posterior cruciate-retaining and posterior stabilized TKA

Background Anterior tibial translation associated with posterior impingement has been reported to be one of the factors limiting flexion after posterior cruciate-retaining (CR) total knee arthroplasty (TKA), especially when posterior condylar offset is decreased postoperatively. On the other hand, its effect on postoperative motion in posterior-stabilized (PS) TKA remains unknown. It has been demonstrated that PS TKA exhibits a consistent posterior femoral rollback during flexion. Thus, we hypothesized that the problem of posterior impingement can be avoided by use of PS TKA. In this study, we examined the relationship between postoperative posterior condylar offset and knee flexion in CR and PS TKAs. Methods In this study, analysis was performed for 20 subjects who underwent bilateral TKAs (one CR and one PS TKA) as well as another group of 50 PS TKAs. All patients could be tracked for a minimum of 2 years. The range of flexion was measured before operation and at follow-up. Preoperative and postoperative posterior condylar offset was evaluated on true lateral radiographs. Results At the follow-up examination, the mean flexion angle was 123° in the CR knees and 131° in the PS knees with a significantly greater improvement observed for the latter group. In the roentgenographic measurement of the posterior condylar offset, no significant difference was observed between the preoperative and postoperative values both in the CR and PS knees. We divided the patients into two groups according to the change of posterior condylar offset. The first group (Group I) showed a decrease in the posterior condylar offset after surgery and the second group (Group II) showed no change or an increase. Subsequently, postoperative change in flexion was compared between Groups I and II for the CR and PS knees. A significant difference between Groups I and II was observed in the CR knees, while no difference was observed in the PS knees. The magnitude of postoperative posterior condylar offset did not correlate with an improvement in maximum flexion angle in the 50 PS knees. Conclusions It was shown that the magnitude of posterior condylar offset correlated with a postoperative change in flexion angle in CR knees, while no such correlation was observed in PS knees.     

膝关节类风湿关节炎伴重度屈曲畸形患者关节置换术后的中长期随访

目的分析膝关节类风湿关节炎(RA)伴重度屈曲畸形行全膝关节置换术(TKA)中长期随访结果,探讨其关键的手术技术和康复措施。方法 1998年1月至2005年12月,18例RA伴重度屈曲畸形患者32膝行TKA,平均年龄38.8岁。RA病程14.2年,畸形时间6.5年;术前畸形67.5°,活动度20.3°,合并内翻畸形3例,外翻11例;术前股四头肌肌力3级7例,4级11例;HSS评分21.1分。术前锻炼股四头肌肌力,术中软组织松解及增加截骨,术后伸直支具及伸膝锻炼。术后1、2、3、6、12个月及以后每年随访,评价关节活动度、生存率、HSS评分等。结果 16例患者获得随访,5～10年随访10例18膝,10年以上6例11膝。最后一次随访,膝关节屈曲畸形3.7°,活动度103.2°,HSS评分为81.4分,与术前相比差异有统计学意义(P<0.05)。2膝翻修,假体生存率93.1%。无感染及侧副韧带损伤。结论通过加强术前术后股四头肌功能训练,术中软组织松解及增加股骨远端截骨,膝关节RA伴重度屈曲畸形患者TKA术后中长期随访效果满意。     

Simultaneous bilateral total knee arthroplasty

Total knee arthroplasty (TKA) was performed simultaneously on both knees by two teams in a single procedure. The study population consisted of 74 patients (148 knee joints) with osteoarthritis (OA) or rheumatoid arthritis (RA). The peri- and postoperative results were compared with those in a group of 22 OA and RA patients (44 knee joints) who underwent staged operation during one hospital stay. Comparisons were made of functional score and range of motion (ROM) before and after operation, mean total blood loss, operative time, duration of hospital stay, and operative and postoperative complications. The simultaneous performance of bilateral procedures did not influence the functional score, ROM after operation, or mean intra- and postoperative blood loss. Nor was incidence of operative and postoperative complications increased compared with that in the staged operation group. The operative time in the simultaneous TKA group was significantly shorter than the time that would have been required had separate procedures been performed on both knees. Simultaneous bilateral TKA is beneficial for the patient.     

全膝置换术后髌骨髌腱角的变化

目的 研究全膝置换术后相同屈膝角度下矢状位髌骨和髌腱之间的角度变化,及其与术后活动度的关系.方法 材料为2002年5月～2003年12月期间做了初次全膝置换的33个关节(30例),诊断包括29个膝骨关节炎、4个类风湿性关节炎,其中20个关节置换了髌骨.男5例,女25例;年龄平均67.3岁.术前和术后1年摄0°、45°、90°侧位X线片,记录术后1年的活动度,测量术前术后不同屈膝度下的髌骨纵轴和髌韧带的夹角,并进行分析.结果 术后1年在屈膝90°时,髌骨与髌腱的角度较术前增大(P＜0.01).更换髌骨和保留髌骨组术后都发生了相似的角度变化(P＜0.01).术后屈膝90°的髌骨髌腱角和术后活动度呈负相关(r=-0.506,P=0.003).结论 全膝置换术后在屈膝活动时的髌骨髌腱角变化规律发生改变,与置换髌骨无关;术后屈膝90°时髌骨髌腱角的改变幅度与术后活动度限制有关.     

Surgical closing in total knee arthroplasty. A series followup

The benefits of closing the surgical wound of a primary and revision total knee prosthesis with the knee in full flexion are examined. A previous study showed that surgically closing the primary knee arthroplasty with the knee in full flexion produced significantly more postoperative flexion at 6 months: 114.7 degrees compared with 108.1 degrees. Of 108 selected sequential primary knee arthroplasties, the first 52 knees were closed surgically with the leg in full knee extension, and the second 56 knees were closed in 90 degrees to 110 degrees flexion, depending on the available motion of the joint. The patients in each group were matched closely in age, weight, height, gender, and surgical technique. At all followup intervals, the flexion measurements were significantly better in the flexion closure group. At 1 year, the flexion group had 117.9 degrees and the extension group had 112.9 degrees flexion. The revision series also was a selected sequential series with 13 knees in each closure group. In the revision case, the 1-year findings were similar, with significantly more knee flexion in the flexion closure group (118.7 degrees compared with 112.7 degrees). In matched groups, flexion closure in primary and revision knee replacements significantly increased total range of motion, as seen at the 1-year followup.     

Results of revision total knee arthroplasty performed for aseptic loosening

One hundred thirty-seven revision total knee arthroplasties (TKA) performed in 117 patients with failed aseptic metal-to-plastic knees over ten years (1974-1984) were studied to determine the long-term clinical and roentgenographic results and were compared to primary TKA. The mean age was 65 years (range, 32-90 years). Fifty-three percent had rheumatoid arthritis, and 47% had osteoarthritis. The mean interval from initial to revision TKA (129 knees) was four years (range, three months to 11 years) and from the first to second revision (seven knees) was 2.4 years (range, seven months to 5.5 years). The most common reasons for failure were loosening (73%), patellar complications (13%), and instability (10%). The mean follow-up time was 5.2 years (range, two to 12 years). Function, instability, motion, and pain all improved after revision TKA, but these improvements were significantly less than those seen after primary TKA. One-third of the patients still ambulated with crutches, a walker, or not at all. While mean postoperative flexion was 100 degrees, 24% could not flex to 90 degrees. Most patients (90%) were malaligned at the time of failure and remained so after revision (78%). The increased incidence of radiolucent lines (tibial, 61%; femoral, 24%) was not related to increased failure. Complications were not increased over primary TKA. The failure rate was 5.8% at 5.2 years, or approximately 1% per year. A successful clinical result was defined as a knee with mild or no pain, mild or no instability, and flexion to at least 90 degrees.(ABSTRACT TRUNCATED AT 250 WORDS)     

增加胫骨平台后倾角度、后交叉韧带部分松解对全膝关节置换术后膝关节运动影响的实验研究

目的通过增加胫骨平台后倾角度或后交叉韧带（PCL）部分松解对全膝关节置换术（TKA）中屈曲间隙过紧进行处理,分析这两种方法对TKA术后膝关节运动学的影响。方法测量6例新鲜尸体膝关节标本在完整状态下、正常TKA、屈曲间隙过紧、增加胫骨平台后倾角以及PCL部分松解TKA术后膝关节屈曲0°、30°、60°、90°、120°时的前后松弛度、内外翻松弛度、旋转松弛度及最大屈曲度。结果屈曲过紧TKA与正常TKA相比,在屈曲30°、60°、90°和120°时前后松弛度、内外翻松弛度及旋转松弛度均显著较小（P〈0．05）。与屈曲过紧TKA相比,增加胫骨后倾角后,在屈曲30°、60°、90°和120°时前后松弛度、内外翻松弛度和旋转松弛度均明显增大（P〈0．05）。PCL部分松解与屈曲过紧TKA相比,在屈曲30°、60°、90°和120°时前后松弛度明显增加（P〈0．05）;旋转松弛度在屈曲30°、60°、90°时明显增加（P〈0．05）。与PCL部分松解相比,增加胫骨后倾角的内外翻松弛度在屈曲30°、60°、90°时明显较大（P〈0．05）;旋转松弛度在屈曲0°、30°、60°和90°时明显较大（P〈0．05）。屈曲过紧TKA的最大屈曲度（120．4°）与正常TKA（130．3°）及增加胫骨后倾角（131．1°）相比明显较小（P〈0．05）。增加后倾角与PCL部分松解（124．0°）相比,最大屈曲度较大,但差异无统计学意义（P=0．0816）。结论屈曲间隙过紧TKA术后膝关节的前后松弛度、内外翻松弛度、旋转松弛度和最大屈曲度均减小;增加胫骨平台后倾角后,前后松弛度、内外翻松弛度、旋转松弛度和最大屈曲度均明显增大;PCL部分松解仅能明显增大前后松弛度。因此对于TKA术中屈曲紧张的膝关节,增加胫骨平台后倾角比PCL部分松解能更好地改善膝关节的运动学。     

全膝关节置换术后膝周持续冰袋加压冷敷的镇痛效果分析

目的：研究人工全膝关节置换术（ TKA）术后膝周持续冰袋加压冷敷的镇痛效果。方法2011年5月至2012年5月,将本组86例欲行单侧TKA的骨关节炎患者随机分成两组：试验组于TKA术后将毛巾包裹的10％盐水冰袋置于膝前、内、外侧冷敷,持续24 h;对照组给予同等规格的常温软包装盐水袋置于膝前、内、外侧外敷,持续48 h;两组均于术后第2天拔除引流管。术后24 h内两组患者均经静脉镇痛泵滴注吗啡行自控镇痛（PCA）,疼痛难以忍受时予以肌注吗啡5～10 mg。通过比较两组患者术后膝关节静息和活动痛视觉模拟（ VAS）评分、隐性失血量、吗啡使用情况、主动直腿抬高时间、屈膝90°时间、膝关节活动度（ ROM）以及并发症来分析膝周持续冰袋冷敷的镇痛效果。结果 TKA术后膝周持续冰袋冷敷的患者,其术后36 h内各时间段以及总的吗啡消耗量明显减少（P＜0.01）,第一次肌注吗啡的时间亦明显推迟。术后第6、12、24、36 h,试验组静息痛VAS评分显著小于对照组（ P＜0.01）,术后24、36 h活动痛VAS评分亦显著小于对照组（ P＜0.01）。术后24 h引流量间接显示,试验组隐性失血量较对照组少（P＜0.01）,患者主动直腿抬高时间、屈膝90°时间以及术后两周膝关节活动度比较,试验组均优于对照组（ P＜0.01）。两组在术后伤口愈合、感染发生率、血压、心率、皮疹、呼吸抑制和尿潴留的监测等方面进行比较,差异均无统计学意义,但试验组恶心呕吐发生率小于对照组。结论人工全膝关节置换术后膝周持续10％盐水冰袋冷敷,有助于减少术后麻醉镇痛剂消耗量,减轻术后早期疼痛,且可以有效减少隐性出血量,可促进膝关节功能恢复,且没有明显的不良反应。     

垫片改良设计对膝关节置换术后临床功能和膝关节运动的影响

目的 探讨膝关节假体垫片设计对膝关节置换术后临床功能和膝关节运动学的影响.方法 分析2007年7月至2009年6月使用GENESIS Ⅱ假体行全膝关节置换术的28例膝关节骨关节炎患者的临床资料,共42膝,平均随访27.7个月.按照使用垫片的种类分为高屈曲垫片组(男性1例,女性14例,23膝;年龄54～74岁,平均62.8岁)和标准组(男性1例,女性12例,19膝;年龄54～74岁,平均64.3岁).通过膝关节评分比较两组的临床功能.采用循环透视和软件分析的方法比较两组病例在膝关节屈伸活动时股骨后滚、伸膝装置力臂等参数,评价垫片设计对膝关节运动的影响.结果 标准组和高屈曲垫片组的术后活动度分别为120°和123°,差异无统计学意义.两组在膝关节学会评分上没有差异.高屈曲垫片组术后的Feller评分高于标准组,差异有统计学意义(P=0.012).在影像学测量上,两组病例在0～120°范围活动时股骨后滚和伸膝装置力臂的差异均无统计学意义;活动范围达到130°时,两组的伸膝装置力臂差异有统计学意义(P=0.034).结论 高屈曲垫片的改良设计在减少膝关节置换术后膝前痛的发生、改善膝关节功能方面有一定的作用;但可能会减小伸膝装置的力臂,从而影响股四头肌的做功.