Bridging the Gap: Do Patient-Reported Outcome Measures Reflect Objective Knee Function After Cartilage Repair?

Area of Science:

• Orthopedics
• Sports Medicine
• Regenerative Medicine

Background:

• Focal knee cartilage defects cause significant pain and functional impairment.
• Patient-reported outcome measures (PROMs) and objective scores assess knee status, but their correlation post-surgery is unclear.
• Understanding this relationship can improve registry data interpretation and clinical decision-making.

Purpose of the Study:

• To investigate the correlation between subjective patient-reported outcome measures (PROMs) and objective clinical findings after knee cartilage repair surgery.
• To determine if PROMs accurately reflect objective functional recovery in patients undergoing cartilage repair.

Main Methods:

• Analysis of 52 patients from the German Cartilage Registry (KnorpelRegister DGOU) who underwent knee cartilage repair.
• Standardized follow-up examinations including PROMs and objective findings using a modified International Cartilage Repair Society (ICRS) score.
• Spearman's rank correlation coefficient used to assess the relationship between subjective scores and objective ICRS scores.

Main Results:

• Moderate, significant negative correlations found between objective ICRS score and Knee Injury and Osteoarthritis Outcome Score (KOOS) Symptoms (ρ = -0.420, p = 0.005) and KOOS Quality of Life (QoL) (ρ = -0.377, p = 0.013).
• Moderate, significant negative correlation also observed between objective ICRS score and the subjective International Knee Documentation Committee (IKDC) score (ρ = -0.305, p = 0.028).
• No significant correlations were found between the objective ICRS score and other KOOS subscales (Pain, Activities of Daily Living, Sport).

Conclusions:

• PROMs offer valuable insights into perceived patient outcomes after knee cartilage repair.
• PROMs do not fully reflect objective functional recovery, highlighting the need for combined clinical assessments.
• Integrating subjective and objective measures enhances the interpretation of outcomes in knee cartilage repair registries.