The Effect of Surgical Technique on Growth-Plate Violations in Simulated Adolescent ACL Reconstructions

Open Access
Author:
Kachmar, Michael C
Area of Honors:
Kinesiology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Stephen Jacob Piazza, Thesis Supervisor
  • Steriani Elavsky, Honors Advisor
Keywords:
  • Orthopedics
  • ACL
  • Pediatric
  • Medicine
  • Surgery
  • Imaging
  • Modeling
Abstract:
Traditional anterior cruciate ligament (ACL) reconstructive techniques lead to growth plate violations that carry a potential for growth deformity when used on skeletally immature patients. The risk of deformity associated with reconstruction of the adolescent ACL is diminished, however, when violations to the growth plate are centralized and of smaller volume. The purpose of this study is to compare how the locations and volumes of femoral growth plate violations are different following simulated ACL reconstructions that employ either anteromedial (AM) or transtibial (TT) approaches. Magnetic resonance (MR) scans of the right knee were collected from 17 adolescent and pre-adolescent participants (10 Male: 7 Female) with a mean age of 11.4 ± 2.0 years. Three-dimensional geometric computer models of the knee were constructed from MR data. Tunnels were placed on each model using both techniques. Tunnels were simulated for multiple drills lengths and diameters. Normalized measures of laterality and volume of growth plate violation were calculated following each simulated surgery. The mean normalized volume of violation to the growth plate for the AM approach was 5.1% compared to 4.7% for TT tunneling. Mean normalized laterality of growth plate violation for the AM approach was 0.59 compared to 0.29 for the TT approach (with 1.00 indicating the most lateral violation location possible). Tunnels created using an AM approach violated a significantly larger percentage of the growth plate’s volume (p = 0.007) and produced a violation that was significantly more lateral (p < 0.001) when compared to the TT approach. These results suggest that caution should be exercised when considering the use of AM tunneling in young patients. Factors such as age and skeletal maturity should be considered when selecting reconstructive approach. Furthermore, the use of shorter- or smaller-diameter tunnels may minimize the risk of unnecessarily large violations in pediatric reconstructions.