Summary

Quadriceps strength, better patient-reported functional outcomes, and a stable knee all demonstrated a positive association with return to increasingly demanding sports postoperative in patients from the STABILITY 1 Study

Abstract

Background

In the Stability randomized clinical trial (RCT) comparing ACL reconstruction with or without Lateral Extra-articular Tenodesis (LET) in young active patients, the addition of a LET resulted in reduced graft failure and graft rupture. The purpose of this study was to investigate the association of knee stability to rate of return to sport.

Methods

The Stability RCT compared hamstring tendon autograft ACLR with or without a Modified Lemaire LET. Patients aged 25 years or less with an ACL deficient knee were included. They also had to have two of the following criteria: 1) Grade 2 pivot shift or greater; 2) Participation in a high risk/pivoting sport; 3) Generalized ligamentous laxity. Return to sport type and level was determined via administration of a questionnaire at 24 months postoperative. High-risk (HR) sport was defined as sports that required sudden change of direction, cutting, or landing from a jump, while low-risk (LR) sport did not require these movements. Low-level (LL) sport was defined as recreational, while high-level (HL) sport was competitive. Secondary outcomes included the 4-Item Pain Intensity Measure (P4), Lower Extremity Functional Score (LEFS), Quadriceps and Hamstrings strength indices, a single-leg hop test, and postoperative knee stability. In this exploratory analysis, we reported the proportion of patients that RTS in each group, along with reasons for not returning. We identified a subgroup of patients that participated in high-risk sports preoperative and report trends in outcomes by group (ACLR vs ACLR+LET) and postoperative sport demand (NR, LRLL, HRLL, LRHL, HRHL).

Results

We randomized 618 patients with a mean age of 18.8 years (range: 14-25), 293 males. Information on return to sport was available for 603 patients at final analysis. The proportion of patients who did not return to sport was similar between the ACLR (11%) and ACLR + LET (14%) groups. For those not returning to sport, lack of confidence and fear of re-injury was the most common cited reason. 553 patients participated in high-risk sports preoperatively. Within this subgroup, there was a trend towards increasing quadriceps strength, LEFS score, and decreasing pain scores, as patients returned to increasingly more demanding levels of sport. Hamstring strength and the hop test limb symmetry index were not associated with the level and type of sport to which patients returned. A stable knee was associated with nearly two times greater odds of return to high-level, high-risk sport postoperative compared to those with persistent rotatory laxity.

Conclusions

At 24 months postoperative, patients who underwent ACLR + LET had a similar return to sport rate as those who underwent ACLR alone. Quadriceps strength, better patient-reported functional outcomes, and a stable knee all demonstrated a positive association with return to increasingly demanding sports postoperative. While the subgroup analysis did not show a statistically significant increase in return to sport with the addition of LET, on returning, the addition of LET kept subjects playing longer by reducing graft failure rates.