A comparative study on effectiveness of patellar resurfacing against non-resurfacing in total knee arthroplasty / 中国修复重建外科杂志

Objective: To investigate the effectiveness of total knee arthroplasty (TKA) with or without patellar resurfacing.

Unilateral patellar resurfacing in bilateral total knee arthroplasty: a randomized controlled study / 北京大学学报(医学版)

Objective:To perform unilateral patellar resurfacing and contralateral patellar retention in bilateral total knee arthroplasty (TKA) randomly,and to compare the clinical effects of patellar retention with patellar resurfacing in TKA.Methods:In the study,14 bilateral knee osteoarthritis (OA) patients were randomized in the bilateral TKA to receive unilateral patellar resurfacing and contralateral patellar retention,including 28 knees,all were females,53 to 78 years old,with average (66.9 ± 7.8) years,and the BMI was (26.3 ± 1.8) kg/m2.All subjects were followed up from 3 to 12 months.The clinical effects were evaluated based on measurements of American Knee Society score (KSS),range of motion (ROM),anterior knee pain,patellar clunk,and patellar tilt angle (PTA).Results:All the wounds healed primarily without significant complications,such as infection,aseptic loosening,patellar fracture and so on.The preoperative KSS scores of patellar resurfacing group were 38.9 ± 22.2,and the scores changed to be 92.4 ± 6.7 after operation,which were added by 53.5 ± 20.3.While in the patellar retention group,the KSS scores were 38.4 ± 20.5 preoperatively,and after operation,which were added to be 92.1 ±4.2,and improved by 53.7 ±21.4.The differences in the changed KSS scores between TKA with and without patellar resurfacing were not statistically significant (Independent t-test,P =0.98).The ROM was changed from 95.4° ± 13.5° preoperatively to 120.4° ± 8.9° postoperatively in the patellar resurfacing group and from 92.9° ± 19.1 ° preoperatively to 120.4 ± 8.4° postoperatively in the patellar retention group.The ROM of the two group were increased by 25.0° ± 14.5° and 27.5° ± 19.4° re spectively.However,no remarkable differences were observed between the 2 groups in the knee ROM (Independent t-test,P =0.70).At the end of the latest follow-up,3 knees in the patellar resurfacing group and 2 knees in the patellar retention group had knee anterior pain,the incidences of anterior knee pain were 21.4％ and 14.3％ respectively.There was no obvious difference for the incidence of post operative anterior knee pain (Chi-square test,P =0.62).The incidences of post-operative patellar clunk in the 2 groups were all with 3 knees (21.4％),which had no significant difference in the 2 groups (Chi-square test,P =1.00).The post-operative PTA were 2.6° ± 2.6° in the patellar resurfacing group and 3.6° ± 2.9° in the patellar retention group,respectively.There was also no statistical difference between the 2 groups (Chi-square test,P =0.36).Conclusion:For knee OA patients with mild or moderate patellar cartilage damage,performing patellar resurfacing or not didn't significantly affect anterior knee pain,patellar clunk,functional outcomes or patellar tracking after TKA.So we suggest retain patella in TKA for OA patients with mild or moderate patellar cartilage damage.

A meta analysis of influence of patellar resurfacing on effect of total knee arthroplasty / 重庆医学

Objective To evaluate the influence of patellar resurfacing and non-patellar resurfacing on the effect of total knee arthroplasty to provide the evidence-based basis for selecting the clinical treatment scheme.Methods The clinical randomized controlled trials(RCT)on the whether having patellar replacement in total knee arthroplasty were retrieved from the databases of Pubmed,Cochrane,Medline,Embase,CNKI and WanFang data.The screening was independently performed by two researchers according to the including and excluding criterion.The related data were extracted.The reoperation rate,knee joint pain score and knee joint score served as the measurement criteria.The RevMan 5.2 software was adopted to conduct the meta analysis.Results Fifteen literatures were included to analyze,involving 1 788 patients,among them 871 cases were in the patellar resurfacing group and 917 case sin the non-patellar resurfacing group.The reoperation rate in the patellar resurfacing group was significantly lower than that in the non-patellar resurfacing group(RR=0.50,95 ％CI:0.33-0.76;P =0.001),moreover the knee joint function was significantly improved(WMD=3.04,95％CI:0.41-5.67;P=0.02).However,the anterior knee joint pain(WMD=0.96,95％CI:-0.85-2.76;P=0.30)and knee joint score(RR=0.81,95 ％ CI:0.50-1.32;P =0.41) had no statistical difference between the two operation modes.Conclusion Conducting patellar resurfacing in total knee arthroplasty can reduce the reoperation risk and improves the postoperative knee joint function,but does not improve postoperative knee joint pain score and knee joint score

Three Dimensional CT-based Virtual Patellar Resection in Female Patients Undergoing Total Knee Replacement: A Comparison between Tendon and Subchondral Method

BACKGROUND: Due to its small size, variable shape, and lack of distinct anatomical landmarks, osteoarthritic knees make a precise patellar resection extremely difficult. METHODS: We performed virtual patellar resection with digital software using three dimensional computed tomography scans of knees from 49 patients who underwent primary total knee replacement at our hospital. We compared 2 commonly used resection methods, the tendon method (TM) and the subchondral method, to determine an ideal resection plane with respect to the symmetry and thickness of the patellar remnant. RESULTS: The TM gave a thicker resected patella, and a less oval cut surface shape, which gives better coverage for a domed prosthesis. Both methods, however, gave a symmetric resection both superior-inferiorly, as well as mediolaterally. CONCLUSIONS: Although TM appears statistically better with respect to the thickness and cut surface shape, only further intraoperative studies with long-term clinical follow-up may provide us with the most appropriate patellar resection method.

A Comparison of Patella Retention versus Resurfacing for Moderate or Severe Patellar Articular Defects in Total Knee Arthroplasty: Minimum 5-year Follow-up Results

PURPOSE: The purpose of this study is to assess the clinical and radiological results of patients who underwent patellar retention or resurfacing for moderate or severe patellar articular defects during total knee arthroplasty and evaluate the clinical efficacy of patellar resurfacing according to the articular defect of the patella. MATERIALS AND METHODS: From May 2003 to March 2006, 252 patients (277 cases) underwent total knee arthroplasty by one surgeon. Intraoperatively, we divided these patients into a moderate articular defect group (50-75%: group I) and a severe articular defect group (75-100%: group II) and randomly performed patellar resurfacing. The average age was 67.2 years. There were 234 female and 17 male patients. The average follow-up period was 74.6 months. Clinical outcomes were analyzed using the Knee Society (KS) knee score. Functional score, Hospital for Special Surgery (HSS) score, Feller patellar score and range of motion (ROM). Radiological outcomes were analyzed using the congruence angle, Insall-Salvati ratio and patella tilt angle. RESULTS: The KS knee score and functional score at the last follow-up were 84.4/73.1 in the retention group and 85.2/71.8 in the resurfacing group (p=0.80, p=0.63) in group I. In group II, the values were 82.1/75.1 and 87.0/71.2, respectively (p=0.51, p=0.26). The HSS score and Feller patella score were 86.7/20.3 in the retention group and 84.3/21.7 in the resurfacing group (p=0.31, p=0.29) in group I. In group II, the values were 91.6/21.2 and 85.5/22.1, respectively (p=0.37/p=0.30). The knee ROM (p=0.36/p=0.41), congruence angle (p=0.22/p=0.16), Insall-Salvati ratio (p=0.16/p=0.21) and patella tilt angle (p=0.12/p=0.19) were not statistically different between the two groups. CONCLUSIONS: In this study, we could not find any correlations between the degree of patellar articular defect and patellar resurfacing in terms of the clinical and radiological results. Therefore, patellar articular defects is thought to be less meaningful in determining patellar resurfacing.

The Mid to Long Term Results of PCL Substitution Type Total Knee Arthroplasty with Using a Scorpio(R) system (Comparison with or without Patella Resurfacing)

PURPOSE: The purposes of this study were to evaluate the clinical results of performing total knee arthroplasty (TKA) with using the posterior substitution (PS) type Scorpio(R) system and to compare the clinical results of the patellar resurfacing group with those of the patellar non-resurfacing group. MATERIALS AND METHODS: 72 TKAs in 51 patients with minimum 7 years' follow-up were evaluated in terms of flexion contracture, the range of motion, the Hospital for Specific Surgery (HSS) knee score and the radiologic findings. We compared the clinical results of 42 cases in 31 patients with patellar resurfacing with those of 30 cases in 20 patients without patellar resurfacing. RESULTS: Flexion contracture, the range of motion and the HSS knee scores were significantly improved after the TKAs. Radiolucencies were found in 14% of the cases on the anteroposterior views of the tibia and in 11% on the lateral views of the femur. One case of aseptic loosening was observed during the follow-up period. There were no significant differences of clinical results between the patellar resurfacing TYAs and the without patellar resurfacing TKAs. CONCLUSION: We achieved favorable results when performing TKAs with the PS type Scorpio(R) system during mid to long term follow-up. There was no significant difference of clinical results between the patellar resurfacing and non resurfacing groups in our study.

Evaluación del componente patelar en artroplastía total de rodilla / Evaluation of patellar resurfacing in total knee arhtroplasty

Ever since the first Total Knee Arthroplasty was made to our present times, a point that still generates controversy is, if the accomplishment of patellar resurfacing will take to a higher global rate of complications. It was the final objective of our work to analyze clinically and radiologically, in addition to satisfaction degree and quality of life surveys, the patellar resurfacing in a sample of total knee arthroplasty made in our center. We can conclude that in our experience, the patellar resurfacing has a low incidence of complications, which do not affect in a significant way the quality of life of the patients carrying on a total knee arthroplasty, which justifies this procedure absolutely.

Desde que se realizan las Artroplastías Totales de Rodilla hasta la fecha, un punto que genera controversia, es, si la realización de un componente protésico patelar llevará a una mayor tasa global de complicaciones. Es por eso que el objetivo de nuestro trabajo fue analizar clínica y radiológicamente, además de encuestas del grado de satisfacción, el componente de recubrimiento patelar en una muestra de las artroplastías totales de rodilla realizadas en nuestro centro. Se concluye que en nuestra experiencia, el uso de recubrimiento patelar tiene una baja incidencia de complicaciones, las cuales no afectan de manera significativa la calidad de vida de los pacientes con artroplastía total de rodilla, lo que justifica plenamente su utilización.

A meta-analysis of resurfacing versus nonresurfacing the patella in total knee arthroplasty / 中国矫形外科杂志

[Objective]To assess the difference of resurfacing versus nonresurfacing the patella in total knee arthroplasty. [Methods]Studies on comparison between resurfacing and nonresurfacing the patella in total knee arthroplasty were identified.All the randomized controlled trials were included for Meta analysis with Rev Man 4.2 software.[Results]Sixteen eligible randomized controlled trials showed 1922 TKA.The result of meta-analysis indicated that the risk of postoperative anterior knee pain was lower in patellar resurfacing group than in patellar nonresurfacing group within 5 years.But the difference did not exist after 5 years.The combined RR was 0.53,95%CI(0.30,0.94).The risk of reoperation had no significant difference in patellar resurfacing group and patellar nonresurfacing group within 5 years.But 5 years later,the risk of reoperation was lower in patellar resurfacing group than in patellar nonresurfacing group.The combined RR was 0.35,95%CI(0.18,0.66).There was no difference in the mean postoperative knee scores(WMD=0.44,95%CI(-1.22,2.09)).[Conclusion]Patellar resurfacing can reduce the risk of postoperative anterior knee pain within 5 years and the risk of reoperation 5 years later after total knee arthroplasty.There is no difference in the mean postoperative knee scores.More carefully designed randomized controlled trials are required to evaluate the difference of resurfacing versus nonresurfacing the patella in total knee arthroplasty.

Patellar Nonresurfacing Versus Patellar Resurfacing in Total Knee Arthroplasty

PURPOSE: To compare the clinical, radiologic results and complications between the patellar non-resur-faced and resurfaced cases in total knee arthroplasty. MATERIALS AND METHODS: From March 1998 to May 2003, the subjects were 37 patellar non-resurfaced and 45 patellar resurfaced cases followed up more than a year among the patients who had total knee arthroplasty in degenerative arthritis. The results were evaluated by the range of motion, Hospital for Spe-cial Surgery (HSS) knee rating score, and Laurin's and Merchant's congruence angle. Student t-test was used in statistical analysis in comparison of both groups. RESULTS: In non-resurfaced group, the range of motion was incrased from 90.6 degree preoperatively to 108.6 degree postoperatively and HSS score from 62.6 to 84.1 respectively, while in resurfaced group, range of motion was increased from 88.2 degree preoperatively to 110.4 degree postoperatively and HSS score from 59.3 to 85.3. There were no significant differences between two groups (p>0.05). There were some patella-asso-ciated complications in each group, and revision due to patella-associated complications were 1 case (3%) and 2 cases (4%) each. So, patella-associated complications and revision rates revealed no significant dif-ferences (p>0.05). CONCLUSION: There is no difference in the clinical results and complications between patella resurfacing and selective non-resurfacing with relatively good cartilage, More follow up is needed for the necessity of revision due to patella-associated complications.

Total Knee Arthroplasty Without Patellar Resurfacing / 대한정형외과학회잡지

PURPOSE: To Analyze the Clinical Results of the Total Knee Arthroplasty without Patellar Resurfacing. MATERIALS AND METHODS: One hundred and eight Total Knee Arthroplasties (Nexgen(R), Zimmer, USA) without resurfacing of the patella, were performed between February 1995 and September 1999, and 89 cases followed up for more than 36 months were analyzed in this study. The follow up period ranged from 36 to 70 months (average 52 months). The diagnosis was degenerative joint disease in 83 cases (93%), rheumatoid arthritis in 5 cases (6%) and avascular necrosis of medial femoral condyle in 1 case (1%). The clinical results were evaluated according to Knee Society Clinical Rating System. RESULTS: The mean preoperative knee score was 34 points (range 5-63 points) according to the Knee Society Clinical Rating System, and the mean preoperative functional score was 38 points (range, 10-61 points). The mean postoperative knee score was 91 points (range 65-98 points) and the mean postoperative functional score 89 points (range, 63-100 points). The current study shows that patellar complications associated with unresurfacing did not occur, with the exception of 2 cases of persistent peripatellar pain, which resolved by a postoperative 6 months with conservative treatment. The patellofemoral joint space was also well preserved even at the 3 and 5 year follow-ups. CONCLUSION: Complications of total knee arthroplasty, such as patellar dislocation or subluxation, rupture of the patellar tendon, and fracture of the patella, can be avoided by not resurfacing the patella. On the basis of our results, there is little evidence to support routine patellar resurfacing in total knee arthroplasty.

Comparison of Results Following Patellar Resurfacing and Non-Resurfacing in Total Knee Arthroplasty

PURPOSE: To evaluate the changes of clinical findings depending on the duration after total knee arthroplasty with or without patellar resurfacing. MATERIALS AND METHODS: Retrospective study of 145 total knee arthroplasties with (70 cases) or without (75 cases) patellar resurfacing was carried out clinically and radioilogically. Patients were evaluated using the knee society score, and the patellar score. RESULTS: No significant difference was found between patellar resurfacing and non-resurfacing knees regarding the knee society score, and the patellar score. The postoperative clinical scores, the postoperative development of anterior knee pain were not influenced by the presence of preoperative anterior knee pain, obesity, the grade of chondromalacia observed intraoperatively, preoperative anteroposterior alignment, or preoperative Insall-Salvati ratio. CONCLUSION: There was no specific difference between the two groups regarding clinical findings, so patellar non-resurfacing should be considered in patients who have relatively normal articular cartilage and patellofemoral joint space width.

Total Knee Arthroplasty without patellar resurfacing

Patello-femoral problem is one of the common complications in total knee arthroplasty and whether to replace the patella or retain it has long been controversial in order to prevent the complications. 43 cases (35 patients) of total knee arthroplasty with patellar retention performed by a single surgeon between August 1993 and August 2000 were reviewed retrospectively. The follow-up period averaged 54 months (range, 24-120 months). The whole cases were divided into three groups according to the preoperative radiographs. Group A was normal patella (10 knees), Group B was borderline arthritic patella (20 knees), and Group C was severely deformed patella (13 knees). All of 43 knees, regardless of preoperative radiological degree of arthritis received patelloplasty including removal of osteophytes, subchondral shaving and lateral retinacular release was performed in 20 knees (47%). Each groups was evaluated in terms of the objective criteria of anterior knee pain, range of motion, stair climbing ability, and roentgenographic findings. All 35 patients were diagnosed as osteoarthritis in 29 and rheumatoid arthritis in 6. American Knee Society Score (KSS) was assessed for the clinical analysis and lateral patella shift and patella tilt were assessed for roentgenographic analysis. The mean Knee Society Score at final follow-up was 94 in group A, 93 in group B, and 94 in group C. Mild anterior knee pain was reported in 9.3% (Group A: 2 cases, Group C: 2 cases). patellar tilt was significantly higher in C group (oneway ANOVA test, p=0.01), representing that advanced patello-femoral arthritis caused increased patellar tilt. There was neither significant difference in terms of range of motion, and stair climbing ability nor of patellar shift among all three groups. TKA with patelloplasty, not resurfacing the patella, provided satisfactory results without significant problems regardless of the preoperative degree of patello-femoral arthritis.