TOPLINE:

Self-reported knee crepitus — an audible crackling or grinding noise during knee movement — was associated with full-thickness cartilage defects in the patellofemoral compartment 1 year after anterior cruciate ligament (ACL) reconstruction but did not predict worsening osteoarthritis (OA) features over 5 years. Additionally, patients with knee crepitus reported worse symptoms initially but experienced greater reductions in pain and improvements in function over time.

METHODOLOGY:

• Researchers conducted a secondary analysis of a longitudinal cohort study to explore the association between self-reported knee crepitus and both the presence and worsening of structural OA features, as well as other self-reported outcomes, between 1 and 5 years after ACL reconstruction.
• At 1 year post-reconstruction, 112 participants (41 women; median age, 28 years) self-reported the presence or absence of knee crepitus using the Knee Injury and Osteoarthritis Outcome Score; a rating of ≥ 3 — corresponding to “often” or “always” experiencing symptoms in the past week — indicated crepitus.
• MRI assessment of the patellofemoral and tibiofemoral knee compartments was performed at 1 and 5 years after ACL reconstruction to examine OA features, including cartilage lesions, osteophytes, and bone marrow lesions.
• Additionally, patient-related outcomes were evaluated, with pain and knee-related quality of life assessed using the Knee Injury and Osteoarthritis Outcome Score subscales and function assessed using the International Knee Documentation Committee subjective evaluation form.

TAKEAWAY:

• At 1 year post-ACL reconstruction, participants reporting knee crepitus were nearly three times as likely to have full-thickness cartilage defects in the patellofemoral compartment (adjusted prevalence ratio, 2.77; 95% CI, 1.14-6.76), with no significant links to other structural OA features in either compartment.
• The presence of knee crepitus did not predict worsening OA features in either the patellofemoral or tibiofemoral compartment over the next 5 years.
• At 1 year post-surgery, those with knee crepitus reported significantly worse outcomes: pain (β = -6.42; 95% CI, -10.47 to -2.36), knee-related quality of life (β = -10.39; 95% CI, -18.58 to -2.20), and self-reported function (β = -5.49; 95% CI, -10.92 to -0.06).
• Over the long term, participants with knee crepitus experienced larger reductions in pain and greater improvements in self-reported function.

IN PRACTICE:

“Health professionals may use these findings to reassure patients that the presence of knee crepitus following traumatic knee injury may not be a prognostic indicator for long-term knee joint health, while also encouraging engagement with appropriate physical activity to maintain (or improve) articular cartilage integrity and person-centered outcomes,” the authors of the study wrote.

SOURCE:

The study was led by Jamon L. Couch, MPhysioPrac, MExSci, La Trobe University in Melbourne, Australia. It was published online on August 25, 2025, in Arthritis Care & Research.

LIMITATIONS:

As a secondary analysis of previously collected cohort data, the study may have been insufficiently powered to detect associations between several outcomes of interest. Despite grouping subregions within knee compartments to increase statistical power, the wide CIs for several OA features suggest that results should be interpreted cautiously. Additionally, participant retention at 5 years post-ACL reconstruction was 70% for MRI data and 72% for self-reported outcomes, which may have introduced attrition bias.

DISCLOSURES:

The study received support from Arthritis Australia, La Trobe University’s Sport, Exercise and Rehabilitation Research Focus Area, and other sources. The authors disclosed having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.