# Trochlear cartilage status at second‐look arthroscopy predicts 2‐year outcomes after around‐knee osteotomy, especially in older patients

## TL;DR

The condition of the trochlear cartilage after knee surgery predicts recovery outcomes, especially for older patients, over two years.

## Contribution

Shows that cartilage status at second-look arthroscopy is a key predictor of long-term recovery after knee osteotomy.

## Key findings

- Abnormal trochlear cartilage is linked to worse outcomes at 24 months, especially in patients over 65.
- Older patients with abnormal cartilage had persistent symptoms, while younger patients showed improvement over time.
- Monitoring cartilage status post-surgery can help guide age-specific treatment strategies.

## Abstract

To investigate whether trochlear surface cartilage degeneration of the patellofemoral joint, assessed by second‐look arthroscopy after around‐knee osteotomy (AKO), affects postoperative patient‐reported outcomes and to examine the influence of patient age on this relationship.

This retrospective cohort study included 331 patients who underwent AKO for varus knee deformity between November 2016 and June 2022. Second‐look arthroscopy was performed approximately 1 year postoperatively, and patients were classified according to femoral trochlear cartilage status at second‐look arthroscopy. International Cartilage Repair Society (ICRS) grades 0–2 were defined as nearly normal and ICRS Grades 3–4 as abnormal for the purpose of this study. The primary outcomes were the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Lysholm score at 2 years. Overlap weighting based on propensity score was used to adjust for confounders.

Of 331 patients, 229 were classified as nearly normal and 102 as abnormal. The abnormal group was older (67.15 ± 8.27 vs. 64.63 ± 9.74 years; p < 0.05) and showed persistently lower KOOS Symptoms at 12 and 24 months. In patients ≥65 years, adjusted 24‑month differences favoured the nearly normal group for KOOS Symptoms (−6.83; 95% confidence interval [CI]−12.48 to −1.19). In younger patients, early KOOS symptom deficits resolved by 24 months.

Trochlear cartilage degeneration observed at second‐look arthroscopy after AKO is associated with poorer 2‐year outcomes, particularly in older patients. These findings suggest that a favourable trochlear cartilage status at second‐look is a meaningful prognostic indicator. Monitoring postoperative cartilage status—especially improvement or stability—may aid in identifying patients likely to achieve better recovery and inform age‐specific treatment strategies.

Level III.

Trochlear cartilage condition after osteotomy predicts 2‐year outcomes, especially in older patients.