Summary

Rehabilitation programs should be individualized and tailored to the specific type of graft used in ACL reconstruction.

Abstract

Introduction

Anterior cruciate ligament (ACL) reconstruction is commonly performed using various grafts, including quadriceps tendon, semitendinosus tendon (SemiT), and semitendinosus combined with gracilis tendon (combined). This study evaluates the recovery of quadriceps and hamstring strength, as well as the jump performance at 6 and 12 months after surgery.

Methods

Quadriceps and hamstring strength were assessed using VALD Performance technology at 6 and 12 months post-operatively, comparing deficits between the operated (OL) and non-operated limbs (NOL). Performance metrics, including drop jump contact time and counter movement jump peak power, were also measured. Mixed-effects models were used to compare the graft groups while accounting for repeated measures. Post-hoc pairwise comparisons were conducted using estimated marginal means with

Significance

level of 0.05.

Results

• Patients: 142 patients (median age 26, range 11-63) who performed 6- and 12-month physical assessment tests were included in the study. For ACL reconstruction, SemiT graft was used in 93 patients (65.5%), quadriceps graft in 36 (25.4%), and combined graft in 13 (9.2%). The three graft groups were comparable in terms of age, gender distribution, BMI, time from injury to surgery, and the incidence of meniscal repairs.
• Quadriceps Strength: Strength deficit significantly decreased in all groups between the 6- and 12-month tests. Patients with a quadriceps graft showed a significantly greater deficit (median: 22.2% at 6 month-test and 11 % at 12 month-test) compared to patients with a SemiT graft (p = 0.007) or combined graft (p = 0.013).
• Hamstring Strength: No significant improvement in strength was observed in any group between the 6- and 12-month tests. At the 12-month test, strength deficit remained ≥ 10% in 61.1% of patients. Additionally, Patients with a SemiT or combined graft demonstrated a significantly greater deficit compared to patients with a quadriceps graft (p = 0.034 and p = 0.367, respectively).
• Hamstring-to-quadriceps ratio (H:Q ratio): The H:Q ratio was decreased in the OL of patients with SemiT or combined grafts compared to the NOL, whereas it was increased in patients with quadriceps grafts. At the 12-month test, the difference in this ratio between the OL and NOL was similar in both the SemiT and quadriceps groups. However, the difference was statistically significant only in the SemiT group (median NOL: 0.98, OL: 0.86; p < 0.01).
• Performance Metrics: Drop jump contact time and counter movement jump peak power demonstrated no significant improvement in all groups.

Conclusion

Graft choice negatively impacted long-term strength recovery in patients after ACL reconstruction. Our results demonstrated a strength deficit on the OL compared to the NOL and revealed that graft harvesting created an imbalance in the agonist-antagonist relationship between the quadriceps and hamstring of the OL, which remained unaddressed during rehabilitation. Therefore, rehabilitation programs should be individualized and tailored to the specific type of graft used in ACL reconstruction.