Outcomes of concomitant lateral extra-articular tenodesis in hamstring anterior cruciate ligament reconstruction in a high-risk population with minimum two-year follow-up. A case series
Elizabeth Monk,1 Jil Wood,2 Ben Waldock,2 Dr Darren Chen,2 Dr Samuel MacDessi,2,3
1. School of Medicine Sydney, The University of Notre Dame, Australia.
2. Sydney Knee Specialists, Kogarah, NSW, Australia
3. St George and Sutherland Clinical School, University of New South Wales, Sydney, NSW, Australia
Background
Australia has the highest incidence of anterior cruciate ligament reconstruction (ACLR) and ACLR revision in the world. It is proposed that the addition of lateral extra-articular tenodesis (LEAT) in ACLR reduces anterolateral rotational instability, thereby reducing loads on the ACL graft and minimising re-rupture rates. There is no clear consensus regarding specific clinical indications for addition of LEAT to ACLR. Current evidence shows significant heterogeneity with regards to patient populations, surgical technique and rehabilitation protocols, making it difficult to draw conclusions about its efficacy. This case series characterises a high-risk subset of patients who have undergone ACLR with LEAT. Clinical indicators for concomitant LEAT included an ACL-deficient knee with high-grade pivot shift plus one or more risk factors associated with ACL graft failure. This series contributes a homogenous data set to the evidence base for future systematic reviews and meta-analyses with the goal of improving the management of patients undergoing ACLR who are deemed to be at ‘high risk’ of ACL graft failure and subsequent revision surgery.
Purpose
To characterise graft survivorship, clinical examination findings and patient-related outcome measures in a specific ‘high-risk’ cohort of patients undergoing ACLR with LEAT using the modified Lemaire technique.
Study Design
Retrospective descriptive case series; Level IV evidence
Methods
A total of 128 patients underwent ACLR with LEAT between June 2015 and July 2017. All patients had experienced knee trauma with signs of ACL rupture on clinical, radiographic and MRI examination. Clinical indications for concomitant LEAT included one or more of the following: Grade 2+ pivot shift; age < 20 years; family history of ACL rupture; history of prior contralateral ACL rupture or revision surgery; generalised joint hypermobility (Beighton score > 4); genu recurvatum > 10°; plan for return to high-level pivot or contact sports or deemed unlikely to comply with full rehabilitation protocol. Patients with multi-ligament injury or previous high tibial osteotomy were excluded. Patient demographics were collected at baseline. The primary outcome was graft failure (re-rupture or revision). Secondary outcomes (assessed preoperatively and at 24+ months postoperatively) included range of motion, instrumented assessment of anterior tibial translation, pivot shift and patient-reported responses. These were collected using the International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS) and Tegner Activity Scale (TAS). Complications, including hardware irritation or contralateral ACL rupture, were also recorded.
Results
Nine patients (7.8%) suffered an ACL graft rupture and three ruptured their contralateral ACL during the study period. Patient-reported outcome measures (PROMs) showed statistically significant (p < 0.001) and clinically meaningful improvements. Postoperative clinical measurements showed restoration to full range of motion by 12 months, and side-to-side comparison of anterior tibial translation showed a mean difference of 1.6 + 0.3mm. The preoperative Grade 2+ pivot shift was eliminated in all except one patient. Twelve patients were lost to follow-up (9.4%).
Conclusion
This case series characterises a ‘high-risk’ cohort of patients with high-grade pivot shift and at least one or more factors associated with risk of ACL graft failure. It shows that the addition of an LEAT with ACLR using the modified Lemaire technique has a graft failure rate comparable to that outlined in the overall literature and reduces rotational laxity as measured by pivot shift, with no impact on range of motion (ROM).