Patellar resurfacing reduces pain after TKA for juvenile rheumatoid arthritis

Influence of patellar resurfacing after knee replacement and the frequency of patella infera and its relation to the postoperative appearance of the knee pain were assessed in patients with juvenile rheumatoid arthritis. Seventy-seven total knee arthroplasties using the AGC prosthesis with nonconstrained components were done on 52 patients with a mean followup of 7.3 years (range, 3-13 years). Anterior knee pain was present in 14 of 30 patients (47%) with an unreplaced patella and in two of 18 patients (11%) with patella resurfacing. The patella was replaced in 18 patients (35%) and in 23 of 77 knees (30%). Neither revision surgery of implanted patellar components nor any later resurfacing of an unreplaced patella were done during the followup. Preoperatively using the Insall-Salvati ratio, the majority of knees (54 of 77) had a low-riding patella. Patella infera occurred commonly in patients with juvenile rheumatoid arthritis. No connection between patella infera and anterior knee pain was found.     

Patellar band for patellofemoral disorders: results and indications.

In patellofemoral disorders, some cases respond well to conservative management thus the authors' initial treatment is conservative. The Patellar Band (PB) was reported previously (Nakamura et al., 1987). Since then the indications for the band have been investigated. Sixty four patients treated by the PB without operative treatment were classified into eight groups. The Severity of Dysfunction (SOD) was assessed by three grades. The First Grade is dull pain after walking or running for a long distance, the Second Grade is sharp pain on climbing up and down stairs, the Third Grade is a feeling of insecurity. The grouping was as follows: Group Ia - plica syndrome with first Grade of SOD and Ib with Second Grade of SOD. Group IIa - chondromalacia with First Grade of SOD and IIb with Second Grade of SOD. Group III - maltracking patella with patellar pain on flexion. Group IVa - subluxation or dislocation of patella with no previous history of patellar symptom and IVb - recurrent dislocation. Group V - degenerative change of the patella. The PB has been proved to be most effective in Groups Ia, IIa and IVb although it is beneficial in half the cases in Groups IIb and III. The subluxation of the patella was partially reduced without recurrence of dislocation during sports activity and the feeling of insecurity was relieved by the PB. The overall results were not related to age or activity level of the patient. The indication of the band for painful knees was not clearly determined in this study. In all operated cases, it was effective for postoperative instability after lateral release of the retinaculum.     

Patellar height and patellofemoral congruence

Summary The patellar tendon/patella ratio and the patellofemoral congruence was estimated in 118 knees. There was a statistically significant positive correlation between the two measurements, high-riding patella occurring with patellofemoral incongruence.

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Zusammenfassung Das Patellarsehnen/Patella-Verhältnis und die Konkruenz des Femoropatellargelenkes wurden in 118 Knien bestimmt. Es zeigte sich eine statistisch zu sichernde Korrelation zwischen Patellahochstand und Inkonkruenz im Femoropatellargelenk.

     

Patellar height and patellofemoral congruence

The patellar tendon/patella ratio and the patellofemoral congruence was estimated in 118 knees. There was a statistically significant positive correlation between the two measurements, high-riding patella occurring with patellofemoral incongruence.     

Patellar resurfacing in total knee arthroplasty

Routine patella resurfacing in total knee arthroplasty has been debated for decades. The early total knee designs and surgical techniques lead to a high complication rate following patellar resurfacing. This lead to many surgeons abandoning this practice and either leaving the patella unresurfaced routinely or selectively resurfacing. Modern day randomized control trials and meta-analyses of these trials reveal a higher incidience of anterior knee pain and a resultant higher reoperation rate in nonresurfaced patellae. We argue that with modern day designs and surgical techniques, there is a low complication rate to resurfacing and little downside to resurfacing.     

Patellar resurfacing in total knee arthroplasty

Whether or not to resurface the patella when performing a primary total knee arthroplasty remains an open question. A number of recent studies have added new information relevant to this controversy. Anatomic studies show that there is normally substantial variability in the anatomy of the trochlear groove. Implanting a femoral component therefore results in a change in the surface topography of the knee in a high percentage of cases. Even though a number of intraoperative techniques have been described in an attempt to accurately reproduce femoral and tibial component rotation, studies of the application of these techniques reveal that component malpositioning or malrotation of a measurable degree occurs in 10% to 30% of cases, depending on the surgical technique and landmarks used. There has been substantial change in the design of both femoral and patellar components in recent years. Even with current designs, biomechanical studies indicate that some degree of change in kinematics and contact stresses occurs following total knee arthroplasty. However, the results of clinical studies have been extremely variable, with most showing either no difference or very little difference between resurfaced and nonresurfaced patellae in osteoarthritic knees. The decision to resurface the patella or not must be individualized on the basis of the surgeon's training and experience and an intraoperative assessment of the patellofemoral articulation.     

Patellar resurfacing in total knee arthroplasty. A meta-analysis

BACKGROUND: Patellar resurfacing during total knee arthroplasty remains controversial. We aimed to evaluate the effectiveness of this technique through an evaluation of the current literature. METHODS: We performed a meta-analysis of randomized controlled trials comparing total knee arthroplasties performed with and without patellar resurfacing. Outcomes of interest included the number of reoperations, the prevalence of postoperative anterior knee pain, and the improvement in various knee scores. RESULTS: Ten trials assessing 1223 knees were eligible. The absolute risk of reoperation was reduced by 4.6% (95% confidence interval, 1.9% to 7.3%) in the patellar resurfacing arm (between-study heterogeneity, p < 0.01; I(2) = 60%), implying that one would have to resurface twenty-two patellae (95% confidence interval, fourteen to fifty-two patellae) in order to prevent one reoperation. Patellar resurfacing reduced the absolute risk of postoperative anterior knee pain by 13.8% (95% confidence interval, 6.4% to 21.2%), implying that one would have to resurface seven patellae (95% confidence interval, five to sixteen patellae) in order to prevent one case of postoperative anterior knee pain. Only four trials provided adequate data for a quantitative synthesis of the changes in the various knee scores; on the basis of those four trials, there was no difference in the mean improvement in the knee scores (standardized mean difference, 0.03; 95% confidence interval, -0.50 to 0.56). CONCLUSIONS: The available evidence indicates that patellar resurfacing reduces the risks of reoperation and anterior knee pain after total knee arthroplasty. The observed effects are clinically important despite their modest magnitude. Additional, carefully designed randomized trials are required to strengthen this claim.     

Patellar resurfacing in total knee arthroplasty

Technical errors in patellar resurfacing at the time of total knee arthroplasty (TKA) are responsible for many of the complications that affect the patellofemoral joint. Instability, patellar fracture, and wear of metal-backed patellar implants are significantly affected by errors of patellar resurfacing. A review of 50 TKAs using a condylar prosthesis and a standardized technique for patellar resurfacing was performed to evaluate the accuracy of the technique. The patients were evaluated at a mean of 2.5 years (range, two to five years) after surgery. The Hospital for Special Surgery Knee Score improved from a preoperative mean of 56 to 92 at the last evaluation. The Hospital for Special Surgery Knee Scores were excellent in 92% and good in 8%. The Knee Society Knee Score improved from a preoperative mean of 28 for pain and 49 for function to a last evaluation mean of 96 for pain and 85 for function. None of the patients had symptoms referable to the patellofemoral joint. There were no patellar fractures, dislocations, or instances of implant loosening of the patella. Roentgenograms revealed nine asymmetrically resurfaced patellae and five tilted patellae. There were no patellar subluxations. Patellar thickness was maintained at the preoperative level of 21 mm. Joint-line height was elevated 1 mm. The patellar height was decreased 2 mm from the preoperative height. Using a standard technique, satisfactory clinical results can be achieved, but minor errors in resurfacing and alignment will still occur.     

Patellar resurfacing versus no resurfacing in Scorpio total knee arthroplasty

This retrospective study compared the results of patellar resurfacing versus no resurfacing in 121 patients (142 knees) who underwent Scorpio total knee arthroplasty (TKA) between January 2002 and September 2004. Mean follow-up was 33 months in the nonresurfaced group and 18 months in the resurfaced group. The 2 groups were similar in age and gender. The incidence of anterior knee pain was 25% in the nonresurfaced group compared to 7% in the resurfaced group (P = 0.05), and the rate of revision was 10% in the nonresurfaced group compared to zero in the resurfaced group (P = 0.013). Mean Euroquol score was 91 in the nonresurfaced group compared to 95 in the resurfaced group (P = 0.26). Euroquol score, Knee Society score, knee instability, return to preoperative functional level, ability to kneel, use of a walking aid, and presence of limp were not significantly different between the 2 groups. The results of this study suggest a more consistent outcome can be achieved with patellar resurfacing in TKA with the Scorpio prosthesis.     

Patellar tracking and patellofemoral geometry in deep knee flexion.

Patellar tracking and femoral condylar geometry in deep knee flexion were evaluated using magnetic resonance imaging. The patellar tilting angle, patellar shift, and patellar anteroposterior translation from 0 degrees to 135 degrees flexion were measured. The depth of the femoral condylar articular surface and the curvature of the femoral condylar articular surface also were measured at 135 degrees flexion. The patella shifted laterally, tilted medially, and sank deeply into the intercondylar notch during deep knee flexion. The articular surface of the lateral condyle, existing deep within the intercondylar notch, began to curve steeply at a point farther from the center of the intercondylar notch than did the medial condyle. The geometry of the femoral condyle is adequate to fit the patellar geometry. Results of the current study suggest that the geometry of the lateral femoral condyle allows the patella to track smoothly with a larger patellofemoral contact area and less patellofemoral pressure during deep flexion.     

Patellar resurfacing complications in total knee arthroplasty

Purpose

The ideal management of the patella during total knee arthroplasty (TKA) is still controversial. Patellar retention is generally associated with an increased rate of anterior knee pain; however, patient satisfaction is similar in cases of replacement or retention. When the patella is replaced, potential severe complications can occur. Aim of this study was to retrospectively review results of a continuous series of patients having been treated with TKA and patella resurfacing.

Methods

The charts of 1,600 consecutive total knee prostheses were analysed to evaluate the rate of patellar resurfacing. All implants were posterior stabilized; 310 patients having received a patellar replacement were reviewed at follow-up (FU) examination. Complete physical examination as well as administration of the Hospital for Special Surgery (HSS) score was performed. X-rays analysis included weightbearing anteroposterior (AP) and lateral views of the injured knee and bilateral skyline views at 30° flexion.

Results

Two hundred and eighty patients were available for clinical and imaging investigation at an average FU of 96 (58–144) months. Mean age at the time of surgery was 70 (62–80) years. Mean HSS score was 85.9 ± 7.6. The overall rate of patellofemoral complications was 7 % (19 cases); 13 patients claimed anterior knee pain, five had symptomatic patellar maltracking and one had patellar component loosening.

Conclusion

Our data are in accordance with those available in the literature. Recent meta-analyses demonstrated lower risk of re-operation after patellar resurfacing. However, when complications of the resurfaced patella occur, they can be potentially catastrophic events.     

Lateral release for patellofemoral arthritis

Purpose: To determine the outcome of treatment of patients with symptomatic patellofemoral osteoarthritis by closed lateral patellar retinacular release. Type of Study: Retrospective study. Methods: Fifty patients who underwent 53 lateral retinacular release procedures between 1995 and 1999 for the treatment of symptomatic patellofemoral arthritis were assessed by questionnaire comprising the Oxford knee score, a visual analogue scale (VAS, 0-10) for pain, and questions relating to level of patient satisfaction. Patients were included in this study whether or not tibiofemoral arthritis was present, but lateral release was performed only in those for whom the anterior knee pain of patellofemoral arthritis appeared to predominate. Results: The average patient age was 53 years (range, 27 to 79 years). There were 14 men (28%) and 36 women (72%). Follow-up was a mean of 31 months (range, 12 to 65 months). Four patients underwent total knee replacement at 7, 14, 16, and 18 months after lateral release for recurrence of symptoms. In the remaining 49 knees, mean pain VAS was 3.8 ± 2.8. In 39 knees (80%), patients judged that they had experienced a reduction in pain compared with their preoperative state (2 were pain free), 8 (16%) were unchanged, and 2 (4%) were worse. The average Oxford knee score was 27 (range, 12-48). At follow-up, 33% of patients were very satisfied, 26% satisfied, and 41% dissatisfied with their knee. The presence of tibiofemoral disease did not affect any of the outcome measures. Two patients developed superficial infections of the arthroscopic port sites. There were no cases of hemarthrosis. Conclusions: Arthroscopic lateral release is effective in reducing the pain of symptomatic patellofemoral osteoarthritis and gives reasonable rates of patient satisfaction irrespective of the presence of tibiofemoral arthritis.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 18, No 4 (April), 2002: pp 399–403     

Patellar resurfacing in total condylar knee arthroplasty. Technique and results

One hundred thirty-two total condylar knee arthroplasties with a 3-8-year follow-up period were studied prospectively with particular reference to the patellofemoral joint. All patients had significant patellofemoral disease and underwent primary patellar resurfacing. After operation 96% of patients had little or no pain and 98% had functional improvement. There were seven (5%) complications related to the patellofemoral joint. The importance of careful attention to preparation of the patella, the technique of prosthetic implantation and correct patellar tracking were emphasized. Routine patellar resurfacing proved highly successful with minimal complications.     

A new method of patellectomy for patellofemoral arthritis.

Total patellectomy, although it has a biomechanical disadvantage in that it may lead to a degree of quadriceps weakness, is frequently indicated in selected patients. Numerous different techniques of performing patellectomy have been described. In this paper, we present a technique of performing a patellectomy in which the continuity of the quadriceps mechanism is not disrupted and the vastuc medialis is advanced. Twenty-six patients (twenty-nine knees) in whom the procedure was performed were studied retrospectively. The findings in this series showed 90 per cent good or excellent results, two cases of extensor lag, an average of 118 degrees of knee flexion, minimum quadriceps atrophy with good strength, and minimum postoperative immobilization. The method presented has the important advantage of an easier, smoother postoperative knee-rehabilitation period, which is extremely advantageous in elderly patients.     

Total knee replacement for patients with patellofemoral arthritis.

Fifty-three patients with incapacitating patellofemoral arthritis and minimal tibiofemoral changes underwent a total knee replacement. Their results were compared with the results of a concomitant series of patients with tricompartmental osteoarthritis. Preoperatively group of patients with patellofemoral arthritis had more individuals with a lateral patellar tilt and inability to climb stairs in a bipedal manner than in the group with tricompartmental arthritis. Furthermore, fewer patients in the group of patients with patellofemoral arthritis could rise independently from a chair than could those patients with tricompartmental arthritis. The mean followup period was 7.4 years. The rate of lateral parapatellar releases was three times greater in the patients with patellofemoral arthritis. The group of patients with patellofemoral arthritis had higher knee scores and a greater ability to climb stairs in a bipedal manner as compared with the patients with tricompartmental arthritis. Residual anterior knee pain was present in approximately 7% of patients in both groups. Total knee replacement resulted in better outcomes for older patients with patellofemoral arthritis as compared with patellofemoral replacement, debridement procedures, and patellectomy.