Primary total knee arthroplasty in the elderly

In a retrospective study, the authors investigated the outcome of primary total knee arthroplasty in patients aged 75 years or older. There is an increased risk of perioperative mortality and medical morbidity, but not surgical morbidity. The results were equal to the younger control group in terms of patient satisfaction, pain relief, stability, range of motion, residual degree of flexion contracture, and extension lag. Mobility was less impressive in the elderly group; factors included were ability to walk, use of walking aids, gait, ability to get out of a chair, and ability to climb stairs.     

The role of flexion contracture on outcomes in primary total knee arthroplasty

This study examined the role that flexion contracture plays in postoperative outcomes after total knee arthroplasty using a retrospective database review. The relationships between preoperative and postoperative knee extension, walking ability, stair climbing ability, Knee Society scores, pain scores, and knee function scores were studied in 5,622 knees. A preoperative flexion contracture was associated with an increased incidence of a persistent postoperative flexion deformity. A postoperative flexion contracture was associated with poorer postoperative results. Furthermore, a postoperative hyperextension deformity of greater than 10 degrees was associated with an increased risk of suboptimal pain and Knee Society scores. Knee extension deformities play a substantial detrimental role in the functional outcome of primary total knee arthroplasty.     

Predicting individual knee range of motion,knee pain,and walking limitation outcomes following total knee arthroplasty

Background and purpose — Up to 20% of patients are dissatisfied after total knee arthroplasty (TKA), mainly because of pain and restricted physical function. We developed a prediction model for 6-month knee range of motion, knee pain, and walking limitations in patients undergoing TKA surgery.

Patients and methods — We performed a prospective cohort study of 4,026 patients who underwent elective, primary TKA between July 2013 and July 2017. Candidate predictors included demographic, clinical, psychosocial, and preoperative outcome measures. The outcomes of interest were (i) knee extension and flexion range of motion, (ii) knee pain rated on a 5-point ordinal scale, and (iii) self-reported maximum walk time at 6 months post TKA. For each outcome, we fitted a multivariable proportional odds regression model with bootstrap internal validation.

Results — At 6 months post TKA, around 5% to 20% of patients had a flexion contracture ³ 10°, range of motion Interpretation — We have developed models to predict, for individual patients, their likely post-TKA levels of knee extension and flexion range of motion, knee pain, and walking limitations. After external validation, they can potentially be used preoperatively to identify at-risk patients and to help patients set more realistic expectations about surgical outcomes.     

Outcome assessment in total knee arthroplasty: is the clinical measurement of range of motion a reliable measurable outcome variable?

AIM: The aim of this clinical study was to investigate the reliability of the clinical assessment (visual and goniometric) of the range of motion of the knee joint. METHOD: 30 patients were assessed concerning the range of motion of their knee joints by visual and goniometric measurements. Assessment was performed by three investigators. The obtained data were used to analyse the intra- and interobserver reliability. Statistical analysis was performed using the Spearman coefficient of correlation [r (s)]. RESULTS: Intraobserver agreement was consistent across observers regarding the visual and goniometric assessment of flexion (r (s) > 0.6), whereas reliability was uniformly low for both measurements regarding the assessment of extension (r (s) < 0.6). Interobserver agreement was consistent across all three goniometric and two out of three visual assessments regarding the measurement of flexion (r (s) > 0.6); the interobserver reproducibility of extension, however, was uniformly low both for the visual and goniometric measurements (r (s) < 0.6). CONCLUSION: Reliability of clinical assessment of range of motion should be taken critically into consideration whilst performing classical function-related scoring systems when measuring outcome after total joint arthroplasty, since these scoring systems are strongly based on a valid and reliable assessment of range of motion.     

Stiffness after total knee arthroplasty. Prevalence of the complication and outcomes of revision

BACKGROUND: Stiffness is an uncommon but disabling problem after total knee arthroplasty. The prevalence of stiffness after knee replacement has not been well defined in the literature. In addition, the outcomes of revision surgery for a stiff knee following arthroplasty have not been evaluated in a large series of patients, to our knowledge. The purposes of this study were to define the prevalence of stiffness after primary total knee arthroplasty and to evaluate the efficacy of revision surgery for treatment of the stiffness. METHODS: We defined a stiff knee as one having a flexion contracture of >/=15 degrees and/or <75 degrees of flexion. Two separate groups were evaluated. First, the results of 1000 consecutive primary total knee replacements were reviewed to determine the prevalence of stiffness. Second, the results of fifty-six revisions performed because of stiffness, sometimes associated with pain or component loosening, after primary total knee arthroplasty were evaluated. RESULTS: The prevalence of stiffness was 1.3%, at an average of thirty-two months postoperatively. The patients with a stiff knee had had significantly less preoperative extension and flexion than did those without a stiff knee (p < 0.0001). There were no significant differences in age, gender, implant design, diagnosis, or the need for lateral release between the patients with and without stiffness. The second cohort, of knees revised because of stiffness, were followed for an average of forty-three months. The mean Knee Society score improved from 38.5 points preoperatively to 86.7 points at the time of follow-up; the mean Knee Society function score, from 40.0 to 58.4 points; and the mean Knee Society pain score, from 15.0 to 46.9 points. The mean flexion contracture decreased from 11.3 degrees to 3.2 degrees, the mean flexion improved from 65.8 degrees to 85.4 degrees, and the mean arc of motion improved from 54.6 degrees to 82.2 degrees. The arc of motion improved in 93% of the knees, and flexion increased in 80%. Extension improved in 63%, and it remained unchanged in 30%. CONCLUSIONS: The prevalence of stiffness in our series of 1000 primary knee arthroplasties was 1.3%. Revision surgery was a satisfactory treatment option for stiffness, as the Knee Society scores improved, the flexion contractures diminished, and 93% of the knees had an increased arc of motion. However, the results suggest that the benefits are modest.     

Osteonecrosis of bipartite patella following total knee arthroplasty without lateral release

We present a case of osteonecrosis of bipartite patella occurring after total knee arthroplasty using medial parapatellar approach without lateral retinacular release in osteoarthritic knee of a 66 year-old-male. The surgery was performed using traditional technique with medial parapatellar approach and patella was resurfaced. Patella was everted during surgery. There was no event during follow-up period after surgery. Range of motion of the knee was 135° without flexion contracture. Eight months after the surgery, patella was fragmented and resorbed on the radiographs which was consistent with osteonecrosis. The patient showed extension limitation of 30° with no pain. Patellar osteonecrosis has been rarely reported after total knee arthroplasty with lateral retinacular release. However, there was no report of patellar osteonecrosis after total knee arthroplasty without lateral retinacular release. Caution should be taken about patellar osteonecrosis in case of bipartite patella even though lateral retinaculum is preserved during total knee arthroplasty.     

Total knee arthroplasty in hemophilic arthropathy of the knee

Twenty-five total knee arthroplasties were performed in 21 patients with hemophilia. The mean patient age was 35.8 years and mean follow-up time was 6.2 years. The average preoperative knee score increased from 18.6 points (range, 3-29) to 82.8 points (range, 44-99). The average preoperative knee function score increased from 41.4 points (range, 20-60 points) to 75.8 points (range, 45-95 points). The average preoperative range of motion was 73.4 degrees with an average flexion contracture of 22.6 degrees, whereas the average postoperative range of motion increased to 92.2 degrees with an average flexion contracture of 5.6 degrees. Median consumption of coagulation factor concentrate decreased from 4837 U/month before operation to 1500 U/month 1 year after surgery. The total knee arthroplasty is a useful treatment in severe hemophilic arthropathy to obtain pain relief and functional improvement, and to reduce the need for ongoing treatment using coagulation factor concentrate.     

Sagittal placement of the femoral component in total knee arthroplasty predicts knee flexion contracture at one-year follow-up

Purpose

Flexion contracture has been shown to impair function and reduce satisfaction following total knee arthroplasty (TKA). The aim of this study was to identify modifiable intra-operative variables that predict post-TKA knee extension.

Methods

Data was collected prospectively on 95 patients undergoing total knee arthroplasty, including pre-operative assessment, intra-operative computer assisted surgery (CAS) measurements and functional outcome including range of motion at one year. Patients were divided into two groups: those with mild flexion contracture (> 5°) at the one-year follow-up and those achieving full extension.

Results

The sagittal orientation of the distal femoral cut differed significantly between groups at the one-year follow-up (p = 0.014). Sagittal alignment of greater than 3.5° from the mechanical axis was shown to increase the relative risk of a mild flexion contracture at one-year follow-up by 2.9 times, independent of other variables.

Conclusion

Increasing the sagittal alignment of the distal femoral cut more than 3.5° from the mechanical axis is an independent risk factor for clinically detectable flexion contracture one year from index procedure.     

重度屈曲畸形膝关节置换术后康复效果研究

目的评价类风湿性关节炎伴膝关节重度屈曲畸形患者行人工膝关节置换术后康复措施的临床效果。 方法回顾性分析2013年6月至2017年9月收治的21例(36膝)类风湿性关节炎伴膝关节重度屈曲畸形患者在人工膝关节置换术后进行功能康复治疗的疗效情况。纳入标准为类风湿关节炎伴膝关节屈曲挛缩角度达60°以上患者,排除标准为存在其它继发性膝骨关节炎者。对所有患者实施系统康复治疗。评估术后、康复出院时以及末次随访的疼痛视觉模拟评分(VAS评分),膝关节屈曲挛缩角度以及膝关节活动范围,进而评估术后康复措施的疗效。根据数据是否符合正态分布,多组间定量资料比较采用单因素方差分析或Friedman秩和检验。 结果在21例患者中,15例(26膝)获得随访,随访时间平均(46±15)个月。术后膝关节VAS评分中位数为7(6,8)分,康复出院时为2(2,3)分,末次随访为0(0,1.7)分,3个时间点的VAS评分组间差异有统计学意义(P<0.001)。术后膝关节屈曲挛缩角度平均为(30±13)°,康复出院时(8±5)°,末次随访为(7±10)°,3个时间点屈曲挛缩角度差异有统计学意义(F＝57.4,P<0.001)。术后膝关节活动范围为(56±21)°,康复出院时(99±11)°,末次随访(88±18)°,3个时间点膝关节活动范围差异有统计学意义(F＝53.8,P<0.001)。 结论类风湿关节炎伴膝关节重度屈曲挛缩畸形的患者行人工膝关节置换术后,经过功能康复治疗后,可实现膝关节功能的改善。     

Effect of range of motion on the success of a total knee arthroplasty

Five hundred fifty posterior cruciate condylar total knee replacements rated on the Hospital for Special Surgery knee rating scale were evaluated to determine whether postoperative range of motion had any detrimental effects on the total score. The amount of flexion significantly influenced the total score (P less than .0003), the stair climbing score (P less than .004), and the walking ability score (P less than .02). Pain, the main determinant of success, was not affected by range of motion unless there was a flexion contracture when there was a significant effect (P less than .05).     

股骨侧假体与胫骨平台角度对膝关节活动度的影响

目的探讨股骨假体屈曲角、胫骨平台后倾角对人工全膝关节置换术后关节活动度的影响。 方法选择2014年1月至2016年12月在广西壮族自治区龙潭医院接受人工全膝关节置换的387例患者病历资料进行回顾性分析,记录患者性别、年龄、身体质量指数、置换关节数、手术时间、术前关节活动度、术前最大屈膝度、术前美国特种医院(HSS)评分、术前疼痛评分、伴随疾病、个人史、康复介入时间、术后1 d疼痛评分、胫骨平台后倾角、股骨假体屈曲角。计量资料组内比较采用配对样本t检验,组间比较采用独立样本t检验,以术后1年患者关节活动度为因变量,其他参数为自变量行秩相关分析和多元回归分析,观察上述指标与术后1年膝关节活动度≥90°的相关性。 结果术前HSS评分为(47±10)分,术后1年HSS评分为(87±6)分,差异有统计学意义(t＝15.820,P<0.01);术前关节活动度为(86±7)°,术后关节活动度为(106±9)°,差异有统计学意义(t＝6.058,P<0.01)。性别、术前关节活动度、术前最大屈膝度、术前HSS评分、胫骨平台后倾截骨角度与膝关节活动度呈正相关(P<0.05);年龄、身体质量指数、置换关节数、术中出血量、术前疼痛评分、高血压、糖尿病、康复介入时间、术后1 d疼痛评分、股骨假体屈曲度与关节活动度呈负相关(P<0.05);手术时间、吸烟、饮酒与术后膝关节活动度无显著相关性(P>0.05)。多元线性逐步回归分析结果显示,胫骨平台后倾截骨角度、股骨假体屈曲角、术前疼痛评分、术前关节活动度是影响膝关节置换术后1年关节活动度的独立因素(P <0.05)。 结论股骨假体屈曲角与全膝关节置换术后关节活动度呈负相关,胫骨平台后倾截骨角度与全膝关节置换术后关节活动度呈正相关。     

屈曲挛缩畸形的膝关节置换术

目的：探讨屈曲挛缩畸形的膝关节行关节置换的方法及疗效。方法：收集膝关节屈曲挛缩畸形病例56例,63膝,行膝关节置换。分别记录术前术后膝关节畸形程度,HSS评分,活动范围。并进行比较。结果：所有病例获得随访,屈曲挛缩畸形均得到改善,膝关节HSS评分由术前20．7分提高到术后平均73．6分。膝关节活动范围由术前平均32．6°（0°～55°）提高到术后平均92．7°（80°～125°）。结论：晚期骨性关节病所致的屈曲挛缩畸形的膝关节行膝关节置换术,着重注意软组织松解,力线调整。疗效满意。     

Radiographic assessment in total knee arthroplasty

Sixty-five total knee arthroplasties were evaluated by the Knee Society Radiological Evaluation System which was developed to encourage uniform reporting of the results of total knee arthroplasty. All patients were examined by three independent experienced radiologists 8.9 years after surgery (range, 3-16 years) to analyze the interobserver variability. For measurement of angles, high interobserver correlation was calculated for the prosthetic component angles and the femorotibial shaft angle. The comparison of the means indicated no significant differences except for the femorotibial shaft angle. For measurement of radiolucent lines, interobserver correlation was low for all components. The differences of the means were significantly different for all components. The results of interobserver variability of the patellar evaluation revealed high interobserver correlation for the patellar angle and for patellar subluxation and dislocation evaluation. For assessment of patellar mediolateral and superoinferior displacement, a low interobserver correlation was found. For radiographic assessment of total knee arthroplasty, the measurement of angles, including alpha, beta, femorotibial shaft angle, sagittal femoral and tibial component angle, patellar angle, and patellar subluxation and dislocation evaluation are recommended. The method of assessing radiolucent lines should be reconsidered.     

Tibial tubercle osteotomy in total knee arthroplasty surgery

Tibial tubercle osteotomy (TTO) is a recognized technique for improving exposure when performing total knee arthroplasty surgery. Forty-two patients were reviewed at a mean of 8 years after TTO. Preoperatively, mean extension was 8 degrees +/- 14 degrees , mean flexion 74 degrees +/- 30 degrees , and Knee Society score 73 +/- 37. At latest follow-up, mean extension was 4 degrees +/- 15 degrees , mean flexion 91 degrees +/- 22 degrees , and Knee Society score 124 +/- 42.6 (P < or = .0001). Seventy-three percent of patients had an excellent/good score at latest follow-up. Twenty-five percent of patients experienced no extensor lag, and 66% of extensor lags had resolved within 6 months. Mean time for osteotomy union was 14 weeks. In this series, TTO performed to enhance surgical exposure did not adversely affect the outcome after total knee arthroplasty but resulted in serious complications in 5% of patients.     

Significance of sagittal stability in knee prosthesis implantation--an analysis of 76 cases with unconstrained joint surface replacement

ISSUE: How does the sagittal stability influence the outcome in unconstrained knee arthroplasty? METHOD: In order to clarify this aspect, 76 arthroplasties (10 male, 66 female, 39x gonarthrosis, 37x rheumatoid arthritis) in 61 patients with unconstrained primary knee arthroplasty were examined with a mean follow-up of 4 years. The determined values were the HSS-Score, the Knee-Society-Score, the range of motion, the flexion contracture as well as the posterior and anterior drawer with the KT 1000. The laxity was defined as the sum of the anterior and posterior drawer. RESULTS: The mean values measured were 2.9 mm for the anterior drawer, 1.9 mm for the posterior drawer and 4.8 mm for the laxity. The total patient population reached 81.3 points in the Knee Score, 70.9 points in the Function-Score and 80.7 points in the HSS-Score. The medium range of motion was determined as 103.5 degrees, the medium flexion contracture as 3.5 degrees. For an anterior drawer of > 6 mm and a posterior drawer of < 1 mm the results deteriorated significantly. A laxity of 8-11 mm gave the best score results. CONCLUSION: An anterior drawer of < 6 mm, a posterior drawer of 2-5 mm and a laxity of 8-11 mm seem to be recommendable for unconstrained knee arthroplasty.     

A comparison of two rehabilitation protocols after total knee arthroplasty: does flexion affect mobility and blood loss?

We report a prospective trial comparing the effectveness of a post-operative flexion regime versus a standard extension regime on the early outcome and on the post-operative blood loss of total knee arthroplasty. Fourty-eight knees were divided to two different post-operative rehabilitation regimes: a flexion regime and an extension regime. The two groups were well matched with respect to age, gender, operation side and pre-op diagnosis All patients were implanted with a NexGen cemented total knee prosthesis and all operations were performed by the same surgeon. Patients were assessed pre-operatively, at the time of discharge, at 6 weeks and at 12 weeks, and were evaluated by means of the Knee Society Score (KSS) and the WOMAC score, the Clarkson criteria for range of motion and muscolar strength measurement, and the Verbal Numeric Scale (VNS) for the pain. Futhermore, postoperative blood loss was assessed by comparing the volume of blood in the drain at the time of their removal and measuring the difference in preoperative and postoperative blood haemoglobin (Hb) in the 2 groups. Patients subjected to the flexion regime had a better KSS and Womac score after 12 weeks and had less post-operative blood loss, requiring fewer blood transfusions. No differences were found between the two groups in terms of pain and muscolar strength. We believe a flexion regime after a total knee arthroplasty is a valid option of rehabilitation treatment and does not result in an increase in wound problems.     

II. Validity and sensitivity to change of the Musculoskeletal Functional Assessment Questionnaire in primary gonarthrosis and total endoprosthetic joint replacement

INTRODUCTION: Scoring systems used so far in total knee arthroplasty are limited by their non-fulfillment of basic test criteria. The aim of the study was to demonstrate the validity and responsiveness of a German version of the new short musculoskeletal function assessment questionnaire (SMFA-D) in patients with primary osteoarthritis and total knee arthroplasty. METHODS: 66 patients with a tricompartmental cemented PFC-Sigma total knee arthroplasty completed the SMFA-D and the WOMAC questionnaire preoperatively and at 12 to 16 weeks follow-up. Preoperatively, physicians' rating of function of the leg, patients' self-selected walking speed, pain and arthritis severity score were registered for demonstration of criterion validity. Construct validity was evaluated with the WOMAC. Discriminant validity was assessed by comparing patients with or without previous surgery at the knee, use of pain medication and use of walking aids. The function and bother indexes of the SMFA-D were correlated with these parameters. Standardized response means were calculated. RESULTS: The function index correlated with physicians' rating (r = 0.51), walking speed (r = 0.61), pain (r = 0.36) and the arthritis severity index (r = 0.36). The bother index correlated with pain (r = 0.37) and the arthritis severity index (r = 0.25). The function and bother index correlated with the WOMAC (r = 0.77) and (r = 0.81), respectively. Patient groups with or without walking aids (p = 0.02) and with or without pain medication (p = 0.001) differed in the function index. The bother index of patients with or without pain medication (p < 0.001) and with or without walking aids (p < 0.006) differed. Function and bother index improved from 46 (SD 17) to 34 (SD 19, p < 0.001) and 43 (SD 18) to 33 (SD 22 p < 0.001), respectively. The standardized response mean was 0.86 for the function index and 0.53 for the bother index. CONCLUSIONS: The SMFA-D questionnaire is valid and responsive in patients with primary osteoarthritis of the knee and total knee arthroplasty. It measures function and bother from the perspective of these patients.     

Outcome of knee arthroplasty in patients with poor preoperative range of motion

In the current study, 27 consecutive total knee arthroplasties in 21 patients were assessed. All patients had a preoperative range of motion of less than 50 degrees, severe debilitation, and a minimum clinical and radiographic followup of 2 years (mean, 6 years; range, 2.3-11.8 years). The mean preoperative arc of motion was 30 degrees (range, 0 degrees -50 degrees) and improved to a mean 74 degrees (range, 15 degrees -110 degrees) postoperatively. Preoperative flexion contracture was corrected from a mean 28 degrees (range, 0 degrees -60 degrees) to a mean postoperative flexion contracture of 4.4 degrees (range, -5 degrees -30 degrees). In this series, the overall complication rate was 41% and the revision rate was 18.5%. The clinical significance of this study is that patients with stiff knees who are debilitated severely can have an improved quality of life after total knee arthroplasty, reflected by an increased walking tolerance, increased functional abilities, and decrease in pain, but in association with a high risk of complications and subsequent revisions.     

Exposure in difficult total knee arthroplasty using coronal tibial tubercle osteotomy

Exposure in a total knee arthroplasty can be challenging regardless of whether it is a difficult primary or a revision. Various techniques both proximal and distal to the patella have been described and implemented to gain exposure and improve knee flexion. When patella eversion is not possible due to previous surgery or severe preoperative knee flexion contracture, a coronal tibial tubercle osteotomy may be utilized. We present successful results utilizing the coronal tibial tubercle osteotomy procedure. The technique involved in this series is based on that described by Whiteside. It involves the development of a long lateral musculoperiosteal flap incorporating the tibial tubercle and anterior tibia, and leaving the proximal tibial cortex intact. This is extended along the tibia distally for 10 cm. It finishes by gradually osteotomising the anterior surface of the tibial crest. The tubercle is reattached with wires at the end of the procedure. This technique minimizes complications that have been associated with the tibial tubercle osteotomy. The 10 knees in 9 patients, who had total knee arthroplasty with a coronal tibial tubercle osteotomy, were reviewed pre and postoperatively. All knees were assessed using the Hospital for Special Surgery knee score (HSS). The scores averaged 43.6 preoperatively (range, 29 57) and 79.2 postoperatively (range, 67 90), and the mean range of motion was 59.5 degrees preoperatively and 78.0 degrees postoperatively. There were no cases of extension lag. Fixed flexion deformity was present in 3 cases postoperatively. Average time to union at the proximal and distal ends of the osteotomy was 8 and 24 weeks respectively. There was no evidence of nonunion and no other significant complications occurred.     

Flexion contracture after total knee arthroplasty in a patient with Parkinson's disease: successful treatment with botulinum toxin type A

The few reports in the orthopedic literature that discuss outcomes after total knee arthroplasty in patients with Parkinson's disease cite mixed results. These patients are at increased risk for the development of flexion contracture, which has been shown to significantly worsen functional scores. The present report describes the development of a flexion contracture in a patient with Parkinson's disease after total knee arthroplasty. This contracture was successfully treated with manipulation under anesthesia and injections of botulinum toxin type A into the hamstring and gastrocnemius muscles, in conjunction with a static progressive extension orthosis and rigorous physical therapy.