Does the grading of chondromalacia patellae influence anterior knee pain following total knee arthroplasty without patellar resurfacing?

Assessment of patellar cartilage cross-sectional area in patients with lower grade chondromalacia patella

Chondromalacia patella (CMP) is abnormal softening of the cartilage of the underside the patella. It is a cause of anterior knee pain. Previous study has demonstrated that the patellar cartilage hypertrophy is correlated with early signs of CMP (Grade 1 or 2). However, no studies have investigated the clinical cutoff value of patella cartilage hypertrophy. Thus, we devised the patellar cartilage cross-sectional area (PCCSA) as a new predictive parameter for diagnosing the CMP. The purpose of this research was to compare MR measured PCCSA between CMP patients and gender matched healthy controls. The PCCSA samples were collected from 50 patients with CMP, and from 50 healthy controls who underwent knee MRI with no evidence of CMP. The T2-weighted turbo spin echo transverse MRI images were acquired. We measured the PCCSA on MRI using a PACS system. The PCCSA was measured on the axial angled sections through the whole images by drawing outlines. The average PCCSA was 104.28 ± 23.28 mm2 in the healthy controls and 134.09 ± 26.55 mm2 in the CMP group. CMP patients had significantly higher PCCSA (P < .001). Regarding the validity of PCCSA as predictors of CMP, Receiver Operating Characteristic curve analysis showed that the best cutoff point for the PCCSA was 116.24 mm2, with 72.0% sensitivity, 72.0% specificity, and the area under curve (AUC) of 0.79 (0.71-0.88). The PCCSA is a sensitive measurement parameter to predict low grade CMP. Thus, to evaluate CMP patients, the treating physician carefully inspect the PCCSA.

Chondromalacia patellae: current options and emerging cell therapies

Chondromalacia patellae (CMP), also known as runner’s knee, typically occurs in young patients, which is characterized by anterior knee pain (AKP) that is associated with visible changes in patellar cartilage. The initial pathological changes include cartilage softening, swelling, and edema. CMP is caused by several factors, including trauma, increased cartilage vulnerability, patellofemoral instability, bony anatomic variations, abnormal patellar kinematics, and occupation hazards. CMP may be reversible or may progress to develop patellofemoral osteoarthritis. Quadriceps wasting, patellofemoral crepitus, and effusion are obvious clinical indications. Additionally, radiological examinations are also necessary for diagnosis. Magnetic resonance imaging (MRI) is a non-invasive diagnostic method, which holds a promise in having the unique ability to potentially identify cartilage lesions. Modalities are conventionally proposed to treat cartilage lesions in the PF joint, but none have emerged as a gold standard, neither to alleviated symptoms and function nor to prevent OA degeneration. Recently, researchers have been focused on cartilage-targeted therapy. Various efforts including cell therapy and tissue emerge for cartilage regeneration exhibit as the promising regime, especially in the application of mesenchymal stem cells (MSCs). Intra-articular injections of variously sourced MSC are found safe and beneficial for treating CMP with improved clinical parameters, less invasiveness, symptomatic relief, and reduced inflammation. The mechanism of MSC injection remains further clinical investigation and is tremendously promising for CMP treatment. In this short review, etiology, MRI diagnosis, and treatment in CMP, especially the treatment of the cell-based therapies, are reviewed.

The patient results and satisfaction of knee arthroplasty in a validated grading system

INTRODUCTION

The validated Knee Osteoarthritis Grading System (KOGS) was implemented and clinical results were compared with patient satisfaction data and implant survivorship in a multi-centre study with surgeons familiar with unicompartmental knee arthroplasty (UKA), patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA). This is also the first study to evaluate the prevalence of UKA and TKA in consecutive osteoarthritis (OA) knee arthroplasties assessed by this system..

METHOD

A consecutive cohort of knees was gathered at three different institutions as categorized by KOGS and surgically treated with the recommended implant unless clinical reasons or patient preference precluded such an option. One thousand one hundred seventy-seven consecutive knees were evaluated including 311 TKA (26%), 695 medial UKA (59%), 154 lateral UKA (13%) and 17 PFA (2%) and the results of the categories evaluated with the Oxford Knee Score (OKS) and the complications reflected in the different categories.

RESULTS

The failure rate of the UKA (3.5%) or TKA (1.6%) is not higher than accepted results in the literature and the difference in complications is negligible between the UKA (72%) and TKA (26%) cohorts. Revision of a UKA to a TKA as an endpoint was 0.58% with ipsilateral progression at 0.8% over a period of five to 84 months (mean follow-up of 36 months) despite the 'excessive' proportion of UKA in this cohort. The Oxford Score improvement is significant in TKA and UKA and contributes to the acceptable outcomes (The OKS for TKA improved from 20 pre-operatively to 36 post-operatively and the UKA improved from 22 pre-operatively to 39 post-operatively).

CONCLUSION

KOGS achieves acceptable early survival and functional results when implemented and is a suitable tool for identifying the preferred implant as was validated.