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Published on: October 27, 2023
Developmental changes in ACLs and semitendinosus tendons dimensions according to age in children
Ryszard Tomaszewski1,2,3, Dominika Smyczek4, Izabela Woś-Cieśla5
1Department of Pediatric Traumatology and Orthopedy, Upper Silesian Child Centre, ul. Medykow 16, 40-752, Katowice, Poland. tomaszewskir@gmail.com.
Insights
Skeletal immaturity complicates anterior cruciate ligament (ACL) injury management. This study provides normative data on semitendinosus tendon (ST) cross-sectional area (CSA) and ACL diameter in pediatric patients using MRI.
Area of Science:
- Orthopedic surgery
- Pediatric radiology
- Sports medicine
Background:
- Anterior cruciate ligament (ACL) injuries in skeletally immature patients present unique management challenges.
- Establishing normative imaging data is crucial for evaluating these injuries and planning reconstructive procedures.
Purpose of the Study:
- To retrospectively collect normative data on the cross-sectional area (CSA) of the semitendinosus tendon (ST) and the diameter of the ACL.
- To analyze the growth patterns of the ST CSA and ACL diameter in children and young adults.
Main Methods:
- Knee MRI examinations were reviewed from 132 patients (ages 8-18 years).
- Measurements included semitendinosus tendon CSA and ACL diameter.
- Two independent researchers performed measurements on axial views.
Main Results:
- Semitendinosus tendon CSA growth was non-linear, with peak growth velocity around ages 12-13.
- ACL diameter growth demonstrated a linear pattern from age 8 to 18 years.
- Magnetic resonance imaging (MRI) proved effective for preoperative assessment of hamstring tendon grafts.
Conclusions:
- Semitendinosus tendon CSA growth is largely complete by age 13.
- ACL diameter increases linearly throughout childhood and adolescence until skeletal maturity.
- MRI is a valuable tool for evaluating hamstring tendon graft parameters in pediatric ACL injuries.
Purpose:
Managing anterior cruciate ligament (ACL) injuries in skeletally immature patients remains difficult. The main aim of this study was to retrospectively compile normative data on the cross-sectional area (CSA) of the semitendinosus tendon (ST) and the diameter of the ACL in children and young adults.
Methods:
Knee magnetic resonance imaging (MRI) examinations were performed for a 2-year period in 132 patients (83 female and 49 male patients). The mean age was 14.9 years (8-18 years). Measurements of the ST CSA were performed on axial views in greyscale by two independent researchers. The ACL diameter was measured as well.
Results:
The results show the CSA of the ST was related to age, and its growth was not linear. The highest growth rate of the CSA of the ST occurred at age 12-13 at the level of the femoral growth plate and at the level of the tibial plateau. The growth of the ACL diameter was linear until 18 years of age.
Conclusions:
ST growth (measured in CSA increments) is almost complete at the age of 13, even though the growth is not linear. ACL growth measured in diameter increments proceeds linearly from 8 to 18 years of age. MRI is a clinically useful tool for assessing hamstring tendon grafts preoperatively.
Level Of Evidence:
Level III, diagnostic studies.
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