Role of Prokineticin-2 and Cytokines in Synovial Fluid in Traumatic Anterior Cruciate Ligament Injuries

Anterior cruciate ligament (ACL) tears induce a proinflammatory intra-articular environment. Despite successful ACL reconstruction (ACLR), post-traumatic osteoarthritis (PTOA) incidence remains high. The role of prokineticin-2 (PK2), a novel inflammatory and pain mediator, was investigated in this observational study of traumatic ACL injuries, associated with meniscal tears.

Twenty patients with isolated ACL tears (ACL group) and 20 with associated meniscal injury (ACL + M group) were enrolled. Synovial fluid PK2, IL-10, and TNF-α levels were measured using ELISA method. Patients underwent long-term follow-up (minimum 5 years) with clinical reassessment using patient-reported outcome measures (PROMs) (IKDC, Lysholm, Tegner activity scale, SKV).

PK2 was detected in both ACL and ACL + M groups without significant differences. Higher PK2 levels were associated with hemarthrosis and correlated positively with IL-10. No associations were found between PK2 levels and demographic factors or time from injury. At follow-up, PK2 negatively correlated with IKDC, Lysholm, and SKV scores.

This study provides initial evidence of PK2 in synovial fluid following ACL injury, suggesting its potential role in knee inflammation. PK2 may represent a candidate biomarker involved in the post-traumatic inflammatory microenvironment; however, further longitudinal studies including structural outcomes are needed.