Stability and early detection of osteoarthritis (OA) following anterior cruciate ligament (ACL) rupture and reconstruction with or without a lateral extraarticular tenodesis (LET)
Abstract
Purpose: Graft failure rates following anterior cruciate ligament reconstruction (ACLR) are inadequate in young, active patients. Recently, the STABILITY 1 Study provided level 1 evidence that augmenting hamstring ACLR with a lateral extra-articular tenodesis (LET) reduces graft failure. Further evidence regarding outcomes after LET and in those with specific risk factors is required.
Methods: This thesis includes three studies. In study 1, we used logistic regression to determine predictors of persistent rotatory laxity and graft failure in young, active patients two-years post-ACLR. In study 2, we investigated a subgroup of patients with lateral meniscal posterior root tears (LMPRT) at the time of ACLR to determine how the injury affected their outcome postoperative. In study 3, we performed magnetic resonance imaging on a consecutive subgroup of patients at two-years postoperative to determine whether augmenting ACLR with LET affects articular cartilage quality in the lateral compartment of the knee.
Results: In study 1, adding an LET was significantly associated with 60% lower odds of graft rupture, while younger age, increased tibial slope, high-grade preoperative knee laxity, and earlier RTS were associated with higher odds of graft rupture. Adding an LET and increasing graft diameter significantly reduced persistent rotatory laxity. In study 2, we found that patients with a LMPRT have similar outcomes to patients without LMPRT, regardless of treatment performed. In study 3, we found that T1rho relaxation was slightly elevated in the lateral compartment for the ACLR + LET group. Cartilage relaxation values increased as meniscal tear size increased when the meniscus was excised, while relaxation times were relatively stable after repair.
Conclusion: Our findings confirm the protective nature of the LET while identifying other predictors of clinical failure and graft rupture. Our results suggest clinicians are skilled at deciding when LMPRTs need to be repaired, and that the meniscus should be repaired, where possible, to prevent changes in cartilage relaxation. This study confirms the need for long-term follow-up of STABILITY 1 patients to determine whether the LET provides short-term stability without increasing increased risk of OA development.