Return to Sport for Skeletally Immature Athletes After ACL Reconstruction: Preventing a Second Injury Using a Quality of Movement Assessment and Quantitative Measures to Address Modifiable Risk Factors

Abstract

Background: Reinjury rates after anterior cruciate ligament reconstruction (ACLR) are highest among young athletes, who consequently suffer from low rates of return to play. Historically, quantitative measures have been used to determine readiness to return to sport; however, they do not assess modifiable risk factors related to the quality of movement.

Purpose: To determine the effectiveness of a criteria-based rehabilitation progression and return-to-sport criteria on efficient return to activity and prevention of second injury in young athletes post-ACLR.

Study design: Case series; Level of evidence, 4.

Methods: Between December 2010 and 2013, 42 skeletally immature athletes (mean chronologic age, 12 years; range, 10-15 years) who underwent ACLR using ipsilateral hamstring tendon autograft were prospectively evaluated. All athletes progressed through a criteria-based rehabilitation progression; were assessed at specific time frames for strength, biomechanical, and neuromuscular risk factors predictive of injury; and were provided targeted interventions. The final return to sport phase consisted of quantitative testing as well as a quality of movement assessment of several functional movements with progressive difficulty and sports-specific loading. Clearance for unrestricted activity was determined by achieving satisfactory results on both qualitative and quantitative assessments with consideration for the demands of each sport.

Results: The mean time for return to unrestricted competitive activity was 12 months. All but 3 (7%) athletes returned to their primary sport. Thirty-five athletes (83%) returned to unrestricted activity. Of the 6 (14%) who sustained a second injury, 3 (50%) were injured in sports they were not cleared for. All ACL reinjuries occurred in a cutting sport. Half of reinjuries occurred within 1 year of surgery, while the remaining occurred between 1 and 2 years. Eighty-three percent of reinjuries involved highly competitive cutting athletes.

Conclusion: In our cohort, the combination of qualitative and quantitative data served as a good indicator for reducing risk and determining readiness to return to sport.

Keywords: ACL injury; ACL prevention; skeletally immature; young athletes.

Conflict of interest statement

The authors declared that they have no conflicts of interest in the authorship and publication of this contribution.

Figures

Figure 1.

A young athlete performing a single-leg hop test with 100% limb symmetry but with poor quality (genu valgum on landing, hip drop, and trunk lean).

Figure 2.

Criteria-based rehabilitation progression. QMA, quality of movement assessment; ROM, range of motion.

Figure 3.

A young athlete performing a squat with (A) a knee strategy and (B) a hip strategy.

Figure 4.

(A) Poor trunk and lower extremity alignment with lateral trunk deviation in the frontal plane, hip shift, and resultant knee valgus loading of the right lower extremity while performing a single-leg squat. (B) Proper trunk and lower extremity alignment: neutral trunk, level pelvis, and no resultant knee valgus while performing a single-leg squat.

Figure 5.

(A) Young athlete demonstrating a shift to the nonoperative left leg while performing a squat at 6 months. (B) The same athlete at 12 months with symmetrical weightbearing during a squat. Note the significant growth in this athlete.

Figure 6.

(A) Young athlete performing a jump in place and landing with decreased depth and knee flexion resulting in increased ground-reaction forces and valgus knee loading bilaterally. (B) Trained young athlete shifting through his hips and knees to absorb the jump landing with no valgus loading of either limb.

Figure 7.

(A) Hop to opposite leg performed by young athlete with proper alignment on his left nonoperative lower extremity but with valgus knee loading when performed to his right lower extremity. (B) Young athlete cutting at 90° with proper trunk and lower extremity alignment followed by a young female athlete with valgus loading. (C) Trained male athlete with proper trunk, hip, knee, and foot/ankle alignment followed by young, untrained female athlete stopping on command with hip internal rotation and knee valgus.