Effect of Graft Rupture Prevention Training on Young Athletes After Anterior Cruciate Ligament Reconstruction: An 8-Year Prospective Intervention Study

Association of Remaining Anterior Knee Laxity With Inferior Outcomes After Revision ACL Reconstruction

Background

The relationship between remaining anterior knee laxity and poorer clinical outcomes after anterior cruciate ligament reconstruction (ACLR) may be underrated, and the criteria for failure of revision ACLR have not been defined.

Purpose/Hypothesis

To evaluate a possible association between remaining knee laxity and functional scores in patients after revision ACLR. We hypothesized that a postoperative side-to-side-difference (SSD) in knee laxity of ≥6 mm will be an objective parameter for failure.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 200 patients (77 women and 123 men; mean age, 30.8 ± 11 years; range, 18-61 years) who underwent revision ACLR between 2016 and 2019 were evaluated; The mean follow-up period was 30.2 ± 9 months (range, 24-67 months). Patients were divided into 3 groups according to postoperative SSD (<3 mm, 3-5 mm, or ≥6 mm). Preoperative and postoperative outcome measures (Lachman, pivot shift, visual analog scale [VAS] for pain, Tegner, Lysholm, International Knee Documentation Committee, and Knee injury and Osteoarthritis Outcome Score) were compared between the groups.

Results

Of the 200 patients, 74% (n = 148) had a postoperative SSD of <3 mm at the latest follow-up, 19.5% (n = 39) had a postoperative SSD of 3 to 5 mm, and 6.5% (n = 13) had a postoperative SSD of ≥6 mm. Patients in all groups saw significant pre- to postoperative reductions in positive Lachman and pivot-shift tests as well as significant improvements in VAS pain, Lysholm, and Tegner scores (P < .001 for all). All postoperative functional scores of the patients with SSDs of <3 mm and 3-5 mm were significantly increased compared with those of patients with an SSD of ≥6 mm (P≤ .01 for all).

Conclusion

In patients following revision ACLR, anterior and rotational knee laxity were successfully reduced while increasing postoperative functional outcomes. A remaining postoperative SSD of ≥6 mm was associated with inferior patient outcomes compared with an SSD <6 mm. An SSD of ≥6 mm represents an objective parameter in the definition of failure of revision ACLR.

Pelvic Rotation Is Associated With Asymmetry in the Knee Extensor Moment During Double-Leg Squatting After Anterior Cruciate Ligament Reconstruction

Asymmetry in knee extensor moment during double-leg squatting was observed after anterior cruciate ligament reconstruction, even after the completion of the rehabilitation program for return to sports. The purpose of this study was to clarify the association between asymmetry in the knee extensor moment and pelvic rotation angle during double-leg squatting after anterior cruciate ligament reconstruction. Twenty-four participants performed double-leg squatting. Kinetics and kinematics during squatting were analyzed using a 3-dimensional motion analysis system with 2 force plates. The limb symmetry index of knee extensor moment was predicted by the pelvic rotation angle (R2 = .376, P = .001). In addition, the pelvic rotation and the limb symmetry index of the vertical ground reaction force independently explained the limb symmetry index of the knee extensor moment (R2 = .635, P < .001, β of pelvic rotation = -0.489, β of vertical ground reaction force = 0.524). Pelvic rotation toward the involved limb was associated with a smaller knee extensor moment in the involved limb than in the uninvolved limb. The assessment of pelvic rotation would be useful for partially predicting asymmetry in the knee extensor moment during double-leg squatting. Minimizing pelvic rotation may improve the asymmetry in the knee extensor moment during double-leg squatting after anterior cruciate ligament reconstruction.

Clinical and arthroscopic outcomes of single-bundle anterior cruciate ligament reconstruction using autologous hamstrings augmented with ligament augmentation and reconstruction systems compared with four-strand hamstring tendon grafts alone

PURPOSE

To compare the clinical, radiological, and second-look arthroscopic outcomes in patients who underwent anterior cruciate ligament (ACL) reconstruction using a four-strand hamstring tendon graft (hamstring group) either without augmentation or with ligament augmentation and reconstruction system (LARS) augmentation (LARS augmentation group).

METHODS

From January 2018 to December 2019, patients who underwent ACL reconstruction were included. Patient-reported outcome measures (PROMs) were undertaken pre-operatively and at three, six, 12, and 24 months post-operatively. Arthroscopic evaluation was performed focusing on the morphology of the graft based on graft tension, graft tear, and synovial coverage.

RESULTS

A total of 178 consecutive patients received single-bundle ACL reconstruction, 89 patients in each group, and 20 patients were lost to follow-up in the first two years. At the three month follow-up, the LARS augmentation group had significantly higher Lysholm scores, IKDC scores, and KOS-ADLS scores than the hamstring group (P < 0.001). At the three, six and 12-month follow-ups, there were significantly higher Tegner scores and ACL-RSI scores in the LARS augmentation group than in the hamstring group (P < 0.05). At the three and six month follow-ups, the LARS augmentation group had significantly higher rates of return to sports and return to sports at their preinjury level (P < 0.05). There were no between-group differences in other outcomes, including arthroscopic outcomes, graft signal intensity, post-operative complications or rerupture rates.

CONCLUSIONS

Autologous hamstring augmented with the LARS augmentation technique provides good and realistic clinical and functional results during the early post-operative period with high levels of satisfaction of patients, including participation in sports and physical activity, and high rates of return to sports at the preinjury level, without any apparent complications compared with hamstring ACL reconstruction alone. No increases in complication, reinjury rates, or increased lateral laxity were observed at the 12-month or 24-month follow-up.

Disagreement in Pass Rates Between Strength and Performance Tests in Patients Recovering From Anterior Cruciate Ligament Reconstruction

BACKGROUND

Performance on strength and functional tests is often used to guide postoperative rehabilitation progress and return to activity decisions after anterior cruciate ligament reconstruction (ACLR). Clinicians may have difficulty in determining which criteria to follow if there is disagreement in performance outcomes among the tests.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare pass rates between strength tests and single-leg hop (SLHOP) tests among men and women and between patients with lower and higher preinjury activity levels recovering from ACLR. We hypothesized that pass rates would be nonuniformly distributed among test types, sex, and activity level and that more participants would pass hop tests than strength tests.

DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 299 participants (146 men; 153 women)-at a mean of 6.8 ± 1.4 months after primary, unilateral, and uncomplicated ACLR (mean age, 23 ± 9.7 years; mean height, 172 ± 10.5 cm; mean mass, 75.8 ± 18.4 kg)-completed testing. Quadri.tif strength was evaluated using peak torque during isokinetic knee extension at 90 deg/s and 180 deg/s. Jump distance during the SLHOP and triple hop tests was measured (in cm). Strength and hop test measures were evaluated based on the limb symmetry index ((LSI) = (ACLR / contralateral side) × 100). We operationally defined "pass" as >90% on the LSI.

RESULTS

Pass rates were nonuniformly distributed between isokinetic knee extension at 90 deg/s and the SLHOP test (χ² = 18.64; P < .001). Disagreements between isokinetic testing at 90 deg/s and the SLHOP test occurred in 36.5% (109/299) of the participants. Among those who failed strength testing and passed hop testing, a greater portion reported higher activity levels before their injury (χ² = 6.90; P = .01); however, there was no difference in pass rates between men and women. Similar patterns of disagreement were observed between all strength test and hop test outcomes.

CONCLUSION

ACLR patients with higher activity levels may be more likely to pass hop testing despite failing quadri.tif strength testing. This may be an indicator of movement compensations to achieve jump symmetry in the presence of quadri.tif weakness.