A. Culvenor1, S. Keays2,3, A. Keays4, N. Collins5
1La Trobe University, La Trobe Sport and Exercise Medicine Research Centre, Melbourne, Australia, 2The University of the Sunshine Coast, School of Health and Sports Sciences, Sunshine Coast, Australia, 3Private Physiotherapy Practice, Sunshine Coast, Queensland, Australia, 4Private Orthopaedic Practice, Sunshine Coast, Queensland, Australia, 5The University of Queensland, School of Health and Rehabilitation Sciences, Brisbane, Australia
Background: Anterior cruciate ligament (ACL) injury is a well-established risk factor for incident knee osteoarthritis (OA). The majority of studies that report OA outcomes do so following surgical management (ACL reconstruction), which has been the traditional gold-standard treatment approach. However, emerging evidence suggesting that clinical outcomes do not differ between ACL reconstruction and non-operative rehabilitation has led to growing calls for (at least trialling) nonoperative management. The long-term development of OA and it’s compartmental distribution in young adults who remain active with ACL deficiency is not well-known.
Purpose: To determine the prevalence of long-term radiographic tibiofemoral (TFOA) and patellofemoral OA (PFOA) in young adults with ACLD compared to: (i) uninjured controls (matched for age, sex and activity level); and (ii) the contralateral uninjured knee.
Methods: 55 participants with ACLD 12(IQR 8,19) years post injury; age 42±9 years; 62% male; pre-injury Tegner Activity Score 8±1.4) and 40 uninjured controls (age 38±11 years; 55% male, Tegner Activity Score 8±1.7) were evaluated. ACLD participants rated their current sport participation level on a 6-point Likert Scale. 18 (33%) were participating in team sports, 16 (29%) in sports involving limited twisting (e.g. surfing, golf, dance), 5 (9%) in running, 10 (18%) in walking or swimming, and 6 (11%) were not physically active. Weight-bearing anteroposterior and non-weight bearing lateral, intercondylar (45o) and skyline radiographs of both knees were acquired (and one randomly selected for analysis in uninjured controls). Kellgren and Lawrence (KL) criteria were used to grade TFOA and PFOA by an experienced rater (AGC) with established reliability. Descriptive statistics were used to present participant characteristics and radiographic OA prevalence.
Results: 54 ACLD participants were included in the between-group comparison (n=1 missing skyline radiograph),46 ACLD participants were included in the within-group comparison (n=2 missing contralateral skyline radiograph; n=6 had contralateral injury/surgery history). The prevalence of TFOA (KLG ≥2) was greater in the ACLD knee (n=19, 36%) compared to matched controls (n=1, 3%) and contralateral knee (n=1, 2%) with the majority having mild-moderate severity (ACLD: KL2 17%, KL3 17%, KL4 2%; controls: KL2 3%, contralateral KL2 2%). Similar results were observed for PFOA, where 18 (33%) ACLD, 0 (0%) controls and 2 (4%) contralateral knees had KLG≥2 (severity ACLD: KL2 24%, KL3 7%, KL4 2%; contralateral: KL2 2%).
Conclusion(s): In mostly active people with ACLD sustained 12 years prior, the prevalence of TFOA and PFOA is higher than in matched controls, and in the contralateral uninjured knee.
Implications: Non-operative rehabilitation aimed at mitigating modifiable risk factors for OA in this population should be incorporated early after injury. Although rehabilitation often targets both limbs to optimise function and minimise the risk of contralateral ACL injury, our findings suggest that rehabilitation aimed at reducing OA risk may not be necessary in the uninjured limb. Further studies are required to understand risk factors for OA development in active individuals with unilateral ACLD.
Funding, acknowledgements: The Private Practitioners Fund at the Nambour General Hospital, Queensland, Australia, covered the cost of most x-rays for this study.
Keywords: anterior cruciate ligament, osteoarthritis, uninjured healthy sportspeople
Topic: Sport & sports injuries
Did this work require ethics approval? Yes
Institution: The University of Queensland
Committee: The Human Ethics Committee
Ethics number: 2008000964
All authors, affiliations and abstracts have been published as submitted.
