Painful Knee is not Uncommon after total Knee Arthroplasty and can be Treated by Arthroscopic Debridement

The biphasic role of the infrapatellar fat pad in osteoarthritis

Osteoarthritis (OA) is a progressive degenerative disease resulting in joint deterioration. It is a whole organ disease characterized by cartilage degeneration and varying degrees of synovitis, involving pathological changes in all joint tissues, such as cartilage, subchondral bone, ligaments, meniscus, synovium, and infrapatellar fat pad (IPFP). IPFP is the largest adipose tissue structure in the knee joint and is composed of fat cells, immune cells and blood vessels. Moreover, IPFP is located close to the cartilage and bone surface so that it may reduce the impact of loading and absorb forces generated through the knee joint, and may have a protective role in joint health. IPFP has been shown to release various cytokines and adipokines that play pro-inflammatory and pro-catabolic roles in cartilage, promoting OA progression. Intra-articular injections of IPFP-derived mesenchymal stem cells and exosomes have been shown to reduce pain and prevent OA progression in patients with knee OA. Previous studies have shown that IPFP has a biphasic effect on OA progression. This article reviews the latest research progress of IPFP, discusses the role and mechanism of IPFP in OA, provide new intervention strategies for the treatment of OA. This article will also discuss the handling of IPFP during the procedure of total knee arthroplasty.

Knee Arthroscopy After Prior Total Knee ArthroplastyType of Study: Narrative Review

Total knee arthroplasty (TKA) results in substantial improvement for most patients with end-stage arthritis of the knee; however, approximately 20% of patients have an unsatisfactory result. Although many problems contributing to an unsatisfactory result after TKA are best addressed by revision TKA, some problems may be effectively addressed with arthroscopic treatment. The categories of pathology that can be addressed arthroscopically include peripatellar soft-tissue impingement (patellar clunk syndrome and patellar synovial hyperplasia), arthrofibrosis, and popliteus tendon dysfunction. Recognizing these disease entities and the role of arthroscopic surgery in the treatment of these lesions may be helpful in achieving a good outcome in certain patients who are unsatisfied with their knee arthroplasty.

Pseudomeniscus after knee arthroplasty: A case series for arthroscopic management of this problem and systematic review of literature

Introduction

Most patients undergoing total knee arthroplasty (TKA) experience favorable outcomes. Some patients, however, experience prolonged post-operative knee pain and tenderness at the joint line. This has been attributed in some cases to soft tissue impingement due to pseudomeniscus. The purpose of this study is to evaluate patient outcomes for arthroscopic excision of pseudomeniscus for persistent knee pain after TKA and to perform a review of literature for pseudomeniscus after knee arthroplasty.

Methods

A retrospective analysis of patients undergoing arthroscopy to remove soft tissue causing persistent knee pain after previous TKA was performed. Outcome scores were asked at three time points: prior to knee arthroplasty, prior to arthroscopy, and post-arthroscopy at final follow-up. Subjective satisfaction with surgery and willingness to repeat procedures were also recorded. A two-tailed distribution paired t-test was used to determine statistical significance (p < 0.05). We also performed a review of the literature for pseudomeniscus complications for comparison.

Results

Nine out of eleven patients were considered eligible to be assessed for post-operative satisfaction. Seven out of nine patients reported complete satisfaction and eight participants stated they would undergo the procedures again if they have to. Among 9 included patients, five patients have successfully completed the clinical score evaluation survey. The mean age of the patients with clinical score evaluation at the time of TKA was 61 years (range, 53-72) and the time between TKA and undergoing arthroscopy was 8 months (range, 5-13). The average follow-up period for patient-determined assessment after the arthroscopic procedure was 71 months (range, 16-115). All 5 patients reported improved Oxford Knee Scores (p=0.017), Western Ontario and McMaster Universities Osteoarthritis Index (p=0.023), and pain scores (p=0.018) comparing pre-arthroscopy to post-arthroscopy at follow-up.

Conclusion

Arthroscopic removal of pseudomeniscus after TKA provides promising results in patients who experience persistent knee joint line pain and tenderness. Considering our results and review of literature, we recommend including pseudomeniscus in the differential for post arthroplasty knee pain.

Study design

Case series with a review of literature.

Arthroscopic management of unexplained pain following total knee arthroplasty

INTRODUCTION

Arthrofibrosis develops in 3-10% of knees after total knee arthroplasty (TKA), which may result in pain and restricted range-of-motion. Treatment options include manipulation under anaesthesia, arthroscopic debridement, and quadricepsplasty, but there is little consensus on their efficacy for treatment of unexplained pain after TKA. The purpose of this study was to report the prevalence and characteristics of unexplained pain after TKA as revealed by arthroscopic exploration, and assess the efficacy of arthroscopic procedures to relieve pain.

MATERIALS AND METHODS

From a consecutive series of 684 TKAs, 11 patients (1.6%) had unexplained pain at 7-48 months after TKA. Causes of pain remained unidentified after systematic and differential assessment, but arthroscopic exploration revealed fibrotic tissues, which were debrided during the same procedure. Patients were assessed first at 6-61 months and last at 90-148 months, with pain on a visual analog scale (pVAS) and range-of-motion recorded during both assessments, but Oxford Knee Score (OKS) and Forgotten Joint Score (FJS) only during the last assessment. Residual pain was classified as little or no pain (pVAS, 0-1), moderate pain (pVAS, 2-4), and severe pain (pVAS, 5-10).

RESULTS

At first follow-up (n = 11) pVAS improved by 4.1 ± 1.1 (p < 0.001), and range-of-motion improved by 5.0° ± 7.1° (p = 0.041). Seven patients (64%) had little or no residual pain, while four (36%) had moderate residual pain. At final follow-up (n = 9) pVAS improved by 3.2 ± 2.9 (p < 0.001), and range-of-motion improved by 4.4° ± 8.5° (p = 0.154). Six patients (67%) had little or no residual pain, while one (11%) had moderate and two (22%) had severe residual pain.

CONCLUSION

Arthroscopic exploration revealed that all 11 knees with unexplained pain had fibrotic tissues, the removal of which alleviated pain in only 67%, while moderate to severe pain persisted in 33% which merits further scrutiny.

The role of knee arthroscopy in managing common soft tissue complications after total knee arthroplasty: a retrospective case series study

BACKGROUND

To investigate the feasibility, safety and therapeutic efficacy of arthroscopy in managing the 3 most common soft tissue complications, peripatellar impingement (PI), arthrofibrosis (AF) and generalized synovitis (GS), after total knee arthroplasty (TKA).

METHODS

A retrospective review of patients undertaking arthroscopy for PI, AF and GS was conducted. Outcome measures included complications, postoperative range of motion (ROM), Knee Society Score (KSS) and rates of symptom recurrence, prosthesis revision. Intraoperative findings and surgical procedures were also recorded. Paired t test, Fisher's exact test, Kruskal-Wallis test and post hoc analysis with Bonferroni correction were used for statistical evaluation.

RESULTS

A total of 74 patients, including 35 patients with peripatellar impingement, 25 patients with arthrofibrosis and 14 patients with generalized synovitis, with a mean age of 66.1 ± 7.9 years, were analysed. The mean follow-up (FU) duration was 81.3 ± 40.6 months. All patients underwent arthroscopic surgery safely without intraoperative complications. However, there were 4 postoperative complications, including 1 acute myocardial infarction and 3 periprosthetic joint infections. Overall, patients acquired improvements in ROM from 81.7 ± 23.1° to 96.8 ± 20.5° (p < 0.05), in KSS knee score from 64.2 ± 9.6 to 78.7 ± 12.1 (p < 0.05) and in KSS function score from 61.1 ± 7.4 to 77.3 ± 12.2 (p < 0.05) postoperatively. Patients in all 3 groups had improvements in ROM (p < 0.05), KSS knee score (p < 0.05) and KSS function score (p < 0.05). The overall recurrence rate was 22.9% (95% confidence interval (CI) 15.1-34.9%), and the overall revision rate was 14.9% (95% CI 8.6-25.6%). There were significant differences in both the symptom recurrence and prosthesis revision rates among the groups (p < 0.05). The PI group had a significantly lower symptom recurrence rate (11.4%, 95% CI 4.5-28.7%) and revision rate (8.6%, 95% CI 2.9-25.3%) (p < 0.017), while the GS group had a significantly higher recurrence rate (42.9%, 95% CI 23.4-78.5%) and revision rate (35.7%, 95% CI 17.6-72.1%) (p < 0.017).

CONCLUSIONS

In the setting of symptomatic TKA, although carrying certain risks for PJI and other complications, arthroscopic intervention could be feasible and provide clinical improvement in most cases at an average of 81.3 months follow-up. Patients with PI had the best outcomes, while patients with GS had the worst outcomes.

LEVEL OF EVIDENCE

Level IV.

Knee Arthroscopy After Total Knee Arthroplasty: Not a Benign Procedure

BACKGROUND

Outcomes of knee arthroscopy (KA) after total knee arthroplasty (TKA) have been limited to small case series with short-term follow-up. The purpose of this study is to report the outcomes of patients who undergo a KA after a TKA using a large longitudinal database.

METHODS

The PearlDiver Medicare database was queried for patients who underwent a KA procedure after a TKA on the ipsilateral extremity. A randomly selected control group was created by matching controls to cases in a 3:1 ratio based on age, gender, year of procedure, and Elixhauser Comorbidity Index. Revision for infection and all-cause revision were used as end points.

RESULTS

A total of192 TKA patients who underwent a subsequent KA (TKA + KA group) were compared to 571 TKA patients who did not have a subsequent KA (TKA - KA group). The incidence of revision for infection was 6.3% in the TKA + KA group compared to 2.2% in the TKA - KA group (odds ratio, 2.87; P = .009). The incidence of all-cause revision was 18.8% in the TKA + KA group compared to 5.1% in the TKA - KA group (odds ratio, 4.34; P < .001).

CONCLUSION

KA after TKA was associated with increased infection-related and all-cause revision. The association between KA and subsequent infection requires further investigation.

Arthroscopic treatment of total knee arthroplasty complications

The most frequent indications for arthroscopy in patients with total knee arthroplasty (TKA) are soft-tissue impingement, arthrofibrosis (knee stiffness), periprosthetic infection and removal of free bodies or cement fragments.

When performing a knee arthroscopy in a patient with a symptomatic TKA, look for possible free/retained bone or cement fragments, which can be anywhere in the joint.

Patellar tracking should be evaluated and soft-tissue impingement under the patella or between the femoral and tibial prosthetic components should be ruled out.

Current data suggest that knee arthroscopy is an effective procedure for the treatment of some patients with symptomatic TKA.

The approximate rates of therapeutic success vary according to the problem in question: 85% in soft-tissue impingement; 90% in arthrofibrosis; and 55% in periprosthetic infections.

More clinical studies are needed to determine which patients with symptomatic TKA can be the best candidates for knee arthroscopy.

Cite this article: EFORT Open Rev 2019;4:33-43. DOI: 10.1302/2058-5241.4.180035.