Physeal sparing technique reduces femoral growth disturbance in pediatric anterior cruciate ligament reconstruction patients.

PURPOSE

The purpose of this study was to compare the difference in limb length and angular deformity between two cohorts of patients who have underwent anterior cruciate ligament (ACL)-reconstruction using a femoral non-physeal sparing technique (N-PS) and a physeal sparing technique (PS). It was hypothesised that N-PS would result in less discrepancy in limb length and knee angles than PS.

METHODS

This is a comparative cohort study of 113 patients: 33 in N-PS who underwent ACL reconstruction between 2001 and 2010, and 80 in PS who underwent ACL reconstruction between 2013 and 2019. Radiographic evaluation, knee stability measurements and patient-reported outcomes (PROMS) were completed at the two-year minimum follow-up examination. Student's t-test, Wilcoxon signed-rank sum test and chi-squared test were used to analyse the data.

RESULTS

At time of surgery, the patients were 11.7 (standard deviation [SD]: 1.4) and 14.0 (SD: 1.3) years old in N-PS AND PS, respectively. N-PS showed a statistically significant difference in femoral length of 3.5 mm (95% confidence interval [CI]: 1.1-5.9) compared to the non-operated side, with no effect on femoral length in PS of 1.0 mm (95%CI: 0.0-1.9).Only a minor impact on tibial angulation (p = 0.07) was observed between the techniques. Sensitivity analysis showed that patients younger than 12.5 years at time of surgery were five times more likely to have a total length difference of more than 10 mm in N-PS than in PS (p = 0.05). Statistically significant differences (p = 0.02) were observed in knee laxity between the N-PS 1.5 mm (95%CI: 1.0-1.2) and PS 2.4 mm (95%CI: 1.9-2.8).

CONCLUSIONS

A femoral physeal sparing technique for paediatric ACL-reconstruction reduced femoral limb length growth disturbance compared with non-physeal sparing technique. Knee laxity was affected and PROMS were unaffected by the type of technique.

LEVEL OF EVIDENCE

Level III.