Selective patellar nonresurfacing in total knee arthroplasty. 10 year results.

Patella nonresurfacing in total knee arthroplasty was reviewed retrospectively in 49 knees (42 patients). Thirteen patients (17 knees) died leaving 29 patients (32 knees) in the final study group. The minimum length of followup was 10 years and averaged 11.7 years (range, 10-13.4 years). The diagnosis was primary osteoarthritis in 26 knees, posttraumatic arthritis in four, osteonecrosis in one, and Paget's disease in one. Patients were evaluated using the Knee Society score, a patella score, and radiographs. The mean Knee Society score improved from 52.8 to 87.5 points postoperatively and functional score improved from 57.5 to 84.5 points postoperatively. Anterior knee pain was reported in six knees (20%). Only one patient required secondary resurfacing of the patella because of postoperative anterior knee pain. No significant correlation was found between anterior knee pain and patellofemoral joint space, patellar sclerosis, Insall-Salvati ratio, patellar tilt, gender, obesity, or age. Based on the need for secondary patellar resurfacing because of anterior knee pain, the 10-year survival was 97.5%. At minimum 10-year followup, retaining the patella in total knee arthroplasty in selected patients with osteoarthritis of the osteoarthritic knee can yield acceptable results.     

Total knee arthroplasty without patellar resurfacing in isolated patellofemoral osteoarthritis

Thirty-one patients (33 knees) with symptomatic patellofemoral osteoarthritis and minimal tibiofemoral changes underwent LCS total knee arthroplasty without patellar resurfacing. Average age was 73 years (range, 58-89 years) with a female-to-male ratio of 5:1. Average follow-up was 20 months (range, 12-40 months). All except 4 patients had grade 3 or 4 patellofemoral osteoarthritis. Preoperatively, all patients had significant knee pain. Sleep disturbance was reported in 21 patients. All but 10 patients required walking aids. Average range of motion was 108 degrees (range, 80-125 degrees ). At latest review, 21 knees were pain-free, the remaining 12 knees being described as having only occasional knee pain. Two patients continued to have night pain. Average range of motion was 104 degrees (range, 70-135 degrees ). Lateral patellar tilt improved in all but 5 knees by an average of 7 degrees (range, 1-26 degrees ). Patellar congruency improved in all but 3 knees by an average of 18% (range, 3-63%). None of the patients to date have required revision surgery. Total knee arthroplasty without patellar resurfacing is an effective option in older patients with isolated patellofemoral osteoarthritis.     

Patellar resurfacing in total knee arthroplasty. A prospective,randomized study

BACKGROUND: Anterior knee pain following total knee arthroplasty is a common complaint and typically is attributed to the patellofemoral joint. The purpose of the present study was to compare the outcome of resurfacing and nonresurfacing of the patella, particularly with regard to anterior knee pain, and to clarify the indications for patellar resurfacing at the time of total knee arthroplasty. METHODS: We performed a prospective, randomized study of 514 consecutive primary press-fit condylar total knee replacements. The patients were randomized to either resurfacing or retention of the patella. They were also randomized to either a cruciate-substituting or a cruciate-retaining prosthesis as part of a separate trial. The mean duration of follow-up was 5.3 years (range, two to 8.5 years), and the patients were assessed with use of the Knee Society rating, a clinical anterior knee pain score, and the British Orthopaedic Association patient-satisfaction score. The assessment was performed without the examiner knowing whether the patella had been resurfaced. At the time of follow-up, there were 474 knees. Thirty-five patients who had a bilateral knee replacement underwent resurfacing on one side only. RESULTS: The overall prevalence of anterior knee pain was 25.1% (fifty-eight of 231 knees) in the nonresurfacing group, compared with 5.3% (thirteen of 243 knees) in the resurfacing group (p < 0.0001). There was one case of component loosening. Ten of eleven patients who underwent secondary resurfacing had complete relief of anterior knee pain. The overall postoperative knee scores were lower in the nonresurfacing group, and the difference was significant among patients with osteoarthritis (p < 0.01). There was no significant difference between the resurfacing and nonresurfacing groups with regard to the postoperative function score. Patients who had a bilateral knee replacement were more likely to prefer the resurfaced side. CONCLUSIONS: As the present study showed a significantly higher rate of anterior knee pain following arthroplasty without patellar resurfacing, we recommend patellar resurfacing at the time of total knee replacement when technically possible.     

全膝置换术后的髌腱短缩及其临床影响

目的研究全膝置换(totalkneearthroplasty,TKA)术后的髌腱长度变化,置换髌骨对髌腱长度的影响,髌腱长度变化与术后膝关节活动度的关系。方法2002年5月~2003年12月对49例55个关节行初次全膝置换手术。包括48例骨关节炎、7例类风湿性关节炎,其中7例做了外侧支持带松解,测量术前的髌腱长度及术后1年的髌腱长度和膝关节活动度,按是否置换髌骨分成两组,对数据进行组间和组内统计学分析。结果术后1年,髌腱发生有统计学意义的短缩(P<0·01)。在短缩大于10%的发生率上,换与不换髌骨组没有统计学意义的差别(P>0·05)。髌腱短缩和关节活动度呈负相关(P<0·01)。结论全膝置换术后存在髌腱短缩的并发症。置换髌骨对髌腱短缩没有影响。髌腱短缩可能是导致术后活动度损失的原因之一。     

膝关节骨关节炎患者初次全膝关节置换术中选择髌骨置换的Meta分析

目的探讨膝关节骨关节炎(OA)进行初次全膝关节置换术(TKA)中选择髌骨置换与否的疗效,评价两种不同治疗选择的差异。方法检索Medline、Embase、Cochranelibrary、CBM,收集膝关节OA行初次TKA术中髌骨置换与否的临床对照试验,提取数据分析,采用RevMan5.0.18进行Meta分析。结果纳入8个前瞻性随机对照试验,共822例手术,其中髌骨置换组373例,髌骨非置换组444例。髌骨置换与非置换组比较,前膝痛与KSS评分均无明显的统计学意义(P0.5),置换组的因髌股关节问题而再次手术率低于非置换组[RR=0.53,95%CI(0.29,0.96),P=0.04],但置换组再次手术的原因除了常见的前膝痛,还包括髌骨假体相关的并发症。结论膝关节OA的患者行初次TKA术中选择髌骨置换与否的前膝痛与KSS评分无明显的统计学意义,置换组的因髌股关节问题再次手术率低于非置换组,但置换组再次手术的复杂性大于非置换组。     

全膝关节置换术中髌骨面修整与髌骨置换的比较研究

目的比较全膝关节置换术髌骨面修整和髌骨置换的临床结果。方法2002年1月至12月对60例（60膝）行初次全膝关节置换术的骨性关节炎患者进行前瞻性、随机化研究。所有患者接受相同的后交叉韧带替代型全膝关节假体（PFC）,患者随机行髌骨面修整（髌骨面修整组）或髌骨置换（髌骨置换组）。58例患者平均随访54个月（40～60个月）,对其进行临床评价,包括膝关节协会评分（KSS）、膝关节活动度（ROM）、患者满意度和X线检查。结果两组患者KSS总评分（P=0．12）、KSS疼痛评分（P=0．90）、患者满意度（P=0．22）无明显差异;两组术后膝前痛的发生率均为10％亦无明显差异。两组ROM（P=0．028）和KSS功能评分（P=0．0098）差异有统计学意义。结论全膝关节置换术不论是髌骨面修整还是髌骨置换均能明显减轻疼痛和改善功能。术后膝前痛可能与假体设计和手术技术有关,并非与是否置换髌骨有关。     

Systematic review of patellar resurfacing in total knee arthroplasty

Controversies existing over resurfacing the patella in total knee arthroplasty remain in the literature. The purpose of this review was to evaluate the effectiveness of resurfacing versus nonresurfacing the patella in total knee arthroplasty. We searched the Cochrane Library, MEDLINE and EMBASE for published randomised clinical trials relevant to patellar resurfacing. The relative risk of reoperation was significantly lower for the patellar resurfacing group than for the nonresurfacing group (relative risk 0.57, 95% confidence interval 0.38–0.84, P = 0.004). The overall incidence of postoperative anterior knee pain of the 1,421 knees included was 12.9% in the patellar resurfacing group and 24.1% in the nonresurfacing group. The existing evidence indicates that patellar resurfacing can reduce the risk of reoperation with no improvement in postoperative knee function or patient satisfaction over total knee arthroplasty without patellar resurfacing. Whether it can decrease the incidence of anterior knee pain remains uncertain.     

Patellar resurfacing in total knee arthroplasty. A prospective, randomized, double-blind study with five to seven years of follow-up

BACKGROUND: Whether to resurface the patella during a primary total knee arthroplasty performed for the treatment of degenerative osteoarthritis remains a controversial issue. Parameters that have been suggested as being useful in guiding this decision include patient height and weight, the presence of anterior knee pain preoperatively, and the grade of chondromalacia encountered intraoperatively. The purpose of this study was to determine whether these parameters were predictive of the clinical result following total knee arthroplasty with or without patellar resurfacing. METHODS: Eighty-six patients (118 knees) undergoing primary total knee arthroplasty for the treatment of osteoarthritis were enrolled in a prospective, randomized, double-blind study. All patients received the same posterior-cruciate-sparing total knee prosthetic components. Patients were randomized to treatment with or without resurfacing of the patella. Evaluations consisted of the determination of a Knee Society clinical score, the completion of a patient satisfaction questionnaire, specific questions relating to patellofemoral symptoms, and radiographs. Sixty-seven patients (ninety-three knees) were followed for a minimum of five years (range, sixty to eighty-four months; average, 70.5 months). RESULTS: With the numbers available, there was no significant difference between the groups treated with and without resurfacing with regard to the overall Knee Society score or the pain and function subscores. Obesity, the degree of patellar chondromalacia, and the presence of preoperative anterior knee pain did not predict postoperative clinical scores or the presence of postoperative anterior knee pain. CONCLUSIONS: The occurrence of anterior knee pain could not be predicted with any clinical or radiographic parameter studied. On the basis of these results, it seems likely that postoperative anterior knee pain is related either to the component design or to the details of the surgical technique, such as component rotation, rather than to whether or not the patella is resurfaced.     

Isolated Resurfacing of the Previously Unresurfaced Patella Total Knee Arthroplasty

Postoperative anterior knee pain can be challenging after primary total knee arthroplasty. Isolated patellar resurfacing may provide symptomatic improvement in those patients with an unresurfaced patella. Seventeen isolated patellar resurfacing procedures were performed. Patient outcomes were evaluated using the Knee Society clinical and roentgenographic evaluation systems. Continued symptomatology and overall patient satisfaction were also analyzed. No revisions have been necessary at 47 months of follow-up. Overall, Knee Society knee scores and knee function scores significantly improved. Eight patients (53%) are asymptomatic and were satisfied with the procedure, whereas 7 patients (47%) continue to have anterior knee pain and are unsatisfied. Isolated patellar resurfacing for anterior knee pain in total knee arthroplasty with an unresurfaced patella has a low morbidity and revision rate but may not provide patients with predictable symptomatic improvement.     

Functional improvement after knee arthroplasty without resurfacing of patella

There has been no universal agreement so far regarding the necessity of patellar resurfacing in total knee arthroplasty. As resurfacing has been reported to be associated with high incidence of complications, this practice has been avoided in our Department. A report is given on the analysis of the functional outcome of 60 knee arthroplasties without patellar resurfacing in 53 patients (7 bilateral) followed up for twelve to thirty months, with special regard to the functions closely related to patelloformal articulation. The underlying diagnosis was osteoarthritis in 78.3%, rheumatoid arthritis in 13.3%, and posttraumatic arthritis in 8.3% of the patients. Graded according to the modified knee-rating system of the Hospital for Special Surgery, excellent or good results were obtained in the case of 55 knees (91.6%) and the mean score improved from 53.6 points preoperatively to 82.6 points following arthroplasty. Subjective and objective functional assessment of stair climbing and transfer activities have shown no functional deficit attributed to the patellofemoral joint of the replaced knee.     

Total knee arthroplasty in an adult with congenital dislocation of the patella

This article reports the use of total knee arthroplasty with release of the lateral retinaculum, proximal extensor mechanism realignment, and patellar resurfacing as a valid treatment option for adult patients with congenital dislocation of the patella who have absence of the femoral sulcus and associated osteoarthritis. The patient presented in this case report had improvement of his Knee Society knee score and function score from preoperative levels of 8 and 45 to 77 and 80 postoperatively.     

Intraobserver and interobserver reliability of the assessment of the patellar articular cartilage in osteoarthritic patients undergoing total knee arthroplasty

This study was performed to investigate intraobserver and interobserver reliability of the intraoperative assessment of patellar cartilage status and the decision on patellar resurfacing based on the cartilage assessment in osteoarthritic patients undergoing total knee arthroplasty. Photographs of patellar cartilage were taken in 80 knees of 53 patients undergoing total knee arthroplasty. Three investigators assessed the depth and size of the cartilage lesion and made a decision on patellar resurfacing, using the photographs twice. Intraobserver and interobserver reliabilities were calculated with the kappa coefficient. Cartilage assessment had substantial intraobserver (kappa = 0.77 for depth and 0.71 for size) and moderate interobserver (kappa = 0.54 for depth and 0.45 for size) reliabilities. Decision on patellar resurfacing had almost perfect intraobserver and substantial interobserver reliabilities (kappa = 0.88 and 0.68, respectively). We found that intraoperative assessment of the patellar articular cartilage and the decision for patellar resurfacing are reliable.     

Patella resurfacing versus nonresurfacing in total knee arthroplasty: results of a randomized controlled clinical trial at a minimum of 10 years' followup

Patellar resurfacing in total knee arthroplasty remains controversial. This study evaluates the results of resurfacing and nonresurfacing the patella in a randomized controlled, clinical trial at a minimum of 10 years followup. One hundred knees (90 patients) with osteoarthritis were enrolled in a prospective randomized clinical trial using a posterior-cruciate-retaining total knee arthroplasty. Patients were randomized to receive resurfacing or retention of the patella. Evaluations were done preoperatively and yearly, up to a minimum of 10 years (range, 10.1-11.5 years) postoperatively. Disease-specific (Knee Society clinical rating score) and functional (stair climbing, flexion/extension torques, patellar examination) outcomes were measured. Patient satisfaction, anterior knee pain, and patellofemoral questionnaires were completed. Intraoperative grading of the articular cartilage was done. No patients were lost to followup; 45 patients remained alive. Nine revisions (in nine of 90 knees; 10%) were done in seven patients in the nonresurfaced group (15% of knees) and in two patients in the resurfaced group (5% of knees). No significant difference was found between the groups regarding revision rates, Knee Society clinical rating scores, and functional, patient satisfaction, anterior knee pain, patellofemoral, and radiographic outcomes. Intraoperative cartilage quality was not a predictor of outcome. This study currently is the longest followup of a randomized controlled, clinical trial that examines patellar resurfacing in total knee arthroplasty. The results showed no significant difference between the groups for all outcome measures at a minimum of 10 years of followup.     

Do we need to replace the patella in knee arthroplasty for rheumatoid disease?

We have examined the anterior knee function in two patient groups who had undergone primary knee arthroplasty without patellar resurfacing to identify differences for osteoarthrosis compared with rheumatoid disease. We identified two consecutive series of patients who had undergone knee replacement surgery for either osteoarthritis or rheumatoid disease between 1992 and 1994 under the care of a single surgeon using the same implant and surgical technique. There were 90 patients in each group. All were examined and asked to complete a questionnaire so as to determine Hospital for Special Surgery (HSS) score, Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) score, Bartlett patellar score and a Visual Analogue score (VAS) for any persistent anterior knee pain at rest. We failed to identify any significant differences in terms of anterior knee function between these two groups of patients. The re-operation rate was similar for both groups. It would appear that primary knee replacement for rheumatoid disease is met with a similarly good outcome for anterior knee function despite absence of patellar resurfacing. We would question the contention that patellar resurfacing is necessary for patients undergoing knee replacement for rheumatoid disease.     

The role of patellar resurfacing in total knee arthroplasty

The ideal treatment of the patella in primary total knee arthroplasty (TKA) for osteoarthritis (OA) remains unclear. Although data exist in the literature to support either resurfacing or not resurfacing the patella, evidence continues to emerge that unresurfaced patellas deteriorate with time. Recent prospective, randomized studies also favor patellar resurfacing over retaining the native patella, reporting reoperation rates to convert unresurfaced to resurfaced patellas exceeding those for complications after patellar resurfacing. In addition, the incidence of residual patellofemoral pain after secondary resurfacing is substantially higher than when patellofemoral resurfacing is done primarily. Patient selection criteria are critical in the decision-making process. Patellofemoral complications, the greatest argument against resurfacing, have been diminished with improved surgical techniques and implant design.     

Secondary resurfacing of the patella in mobile-bearing total knee arthroplasty

OBJECTIVE: We aim to evaluate the impact of secondary patellar resurfacing in patients with patellar-related anterior knee pain who have undergone a mobile-bearing primary knee arthroplasty without resurfacing. MATERIALS: A total of 2950 primary Low Contact Stress (DePuy, Warsaw, Ind) mobile-bearing knee arthroplasties without patellar resurfacing were carried out between March 1992 and March 2003. Thirteen patients (0.4%) underwent secondary patellar resurfacing for patellar-related anterior knee pain. The mean age of the patients was 67.8 years. There was a mean time of 28 months to the secondary resurfacing procedure. RESULTS: Only 4 patients had an unequivocal improvement in their symptoms at a mean follow-up of 45 months (range, 3-92 months). No morbidity was noted from the procedure. CONCLUSION: The success rate of secondary patellar resurfacing is poor and patients should be counseled carefully.     

Patella resurfacing in posterior stabilised total knee arthroplasty: a follow-up study in 56 patients

Patellar resurfacing in total knee arthroplasty (TKA) remains controversial. This study evaluates the results of resurfacing and non-resurfacing of the patella. Fifty-six patients with osteoarthritis (OA) of the knee were enrolled in a prospective randomised clinical trial using a posterior-stabilised TKA. Evaluations were done preoperatively and after 1, 3, 6, 12 and 24 months. Disease specific (Knee Society Score or KSS) and functional (patella-related activities) outcomes were measured. Patient satisfaction and anterior knee pain questionnaires were completed. No patients were lost to follow-up. No significant differences were found between groups with regard to the clinical part of the Knee Society score (KSS) not even in obese patients, the ability of performing daily activities involving the patellofemoral joint, and patient satisfaction. Significant differences were found regarding the functional section of the KSS, passive flexion, anterior knee pain and patellar tilt and subluxation. In conclusion, the authors believe that, for the implant studied, patellar resurfacing can be indicated.     

髌骨钻孔减压改善全膝关节置换术后膝前疼痛

目的探讨通过髌骨钻孔减压术改善全膝关节置换术(TKA)后膝前痛的临床疗效。方法将符合标准的113例行TKA的骨关节炎患者按数字法随机分为两组:54例为减压组,TKA术中联合髌骨钻孔减压术;59例为非减压组,仅施行TKA不联合髌骨钻孔减压术。术后观察两组患者切口愈合情况、相关并发症、KSS评分及膝前痛发生率。结果两组患者切口均一期愈合,无严重并发症发生,113例均获满12个月的完整随访。KSS评分:减压组术后明显高于非减压组;术后膝前痛的发生率明显低于非减压组,差异均有统计学意义(P0.05)。结论 TKA术中联合髌骨减压术可以在一定程度上改善膝关节KSS评分及降低术后膝前疼痛的发生率。     

髌骨置换与否对全膝关节置换术后疗效的影响

目的 探讨膝骨关节炎患者行全膝关节表面置换时髌骨置换与否对术后疗效及并发症发生的影响.方法 对2007年1月至2011年12月之间行人工全膝关节置换术的170例(237膝)骨关节炎患者,按髌骨置换(126膝)和未置换(111膝)分为2组.对术前和末次随访时两组的HSS评分、膝前痛评分、膝关节活动度、最大屈曲度数、屈曲畸形及手术时情况和患者满意度等进行对比分析.结果使用SPSS 17.0统计软件包进行统计学分析.结果 在170例(237膝)OA患者中161例(21 3膝)获得随访,平均随访时间(40.94±8.02)个月,置换组HSS评分由术前的(40.19±8.14)分增加到末次随访时的(87.45±6.00)分(P＜0.05),膝前痛评分由(4.13±1.08)分升高到(19.47±4.04)分(P＜0.05);未置换组HSS评分由(40.00±6.74)分上升到(88.93±4.92)分(P＜0.05),膝前痛评分由(3.58±2.26)分变化到(13.61±3.89)分(P＜0.05);患者满意度置换组为80.91％,未置换组为61.17％(P＜0.05).在HSS评分、膝关节活动度、最大屈曲度数、屈曲畸形等方面两组差异无统计学意义.而在膝前痛评分、患者满意度、手术时间、术中失血量等方面差异有统计学意义.结论 当膝关节骨关节炎患者进行全膝关节置换术时,若术前存在膝关节疼痛严重、患者期望较高、不适合长时间手术,应行髌骨置换.     

Patellar resurfacing for patellofemoral arthritis.

Knee pain referable to the patellofemoral articulation is common in the general population. It remains a troubling problem for the orthopedic surgeon. Frequently, initial therapy, involving activity modification, anti-inflammatory medications, and isometric quadriceps strengthening, is successful in relieving symptoms. Surgical intervention is normally reserved for those patients with pain that is resistant to these modalities. Unfortunately, none of the various surgical options has proved to be totally dependable, durable, or reproducible. The results of isolated patellar and patellofemoral resurfacing procedures have been guarded. Patellar resurfacing appears to be most beneficial in younger patients with severe anterior knee pain. These individuals should be clearly warned that there is a relatively high likelihood that they will require additional surgical treatment or patellectomy at a later date. Fortunately, patellar resurfacing does not preclude patellectomy from being easily performed. Patellofemoral resurfacing, however, involves more overall involvement of the knee joint. This makes patellectomy less likely to be a successful salvage procedure. Despite our observations that knees with primary patellofemoral arthritis do not do as well after total knee replacement as those with tibio-femoral arthritis, this procedure remains the best treatment option. The durability and predictability of total knee arthroplasty are well documented. Its results far surpass those reported for isolated resurfacing procedures. With regard to patellar resurfacing as part of total knee arthroplasty, we recommend resurfacing all patellae. The literature, although not conclusive, lends support to this practice. Avoidance of metal-backed patellar components and special attention to technical details should decrease the complications associated with patellar resurfacing in future studies.(ABSTRACT TRUNCATED AT 250 WORDS)