Radiolographic assessment of lower limb alignment in South African children
Date
2022-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Background:
Radiographic measurements on full length standing lower limb views are the
standard for lower limb deformity analysis. Published measurements of Paley et al.
on lower limb alignment is the gold standard but was derived from small adult
samples. There are no radiographic measurements reported exclusively of children
of South African descent. The study aimed to establish normal values of lower limb
alignment and joint orientation angles in South African children between 5 and 18
years old, at specific age intervals and to compare these measurements to the
values as derived from Paley et al.
Methods:
A cross-sectional radiographic study including all 5-18 year old children who
underwent full-length anteroposterior radiographs between 2012 and 2020 was
conducted. Radiographic measurements were done as described by Paley.
Differences in measurements obtained and those reported by Paley et al.1 were
investigated using a T-test for a single mean against a reference constant, using an
alpha level of 0.05.
Results:
A total of 190 patients (110 male; 80 female) with a mean age of 10.0 ± 3.3 years
were included. The medial neck-shaft angle (MNSA), mechanical and anatomical
lateral distal femoral angle (LDFA) and lateral distal tibia angle (LDTA) remained
consistent throughout the age groups. Significant differences between Paley’s
published values and our cohort were observed for the median mechanical axis
deviation (MAD), MNSA and medial proximal tibia angle (MPTA). The median MAD
across age groups was -2.2 mm (IQR -6.4 – 1.5) with all subgroups showing a lateral
MAD (valgus alignment), compared to the median MAD of +9.7mm (varus alignment)
from Paley et al.1 The MNSA had a mean of 135.7°, compared to 129.7° from Paley.
The mean MPTA was 89.7°, compared to Paley’s 87.2°. The MPTA had minimal
change throughout the age groups. Conclusion:
Significant differences were seen in the mean/median of our MAD, MNSA and MPTA
compared to Paley’s work. Our MAD have a sustained valgus tibio-femoral
angulation throughout our population. Our MNSA have more pronounced valgus with
minimal change throughout growth. The increasing MPTA leads to a more valgus
joint line when compared to other studies. Other measured values are comparable
with previously published adult and paediatric populations.
We were able to develop set values that could be the norm for paediatric joint
orientation angles in the South African population.
AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar.
AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar.
Description
Thesis (MMed) -- Stellenbosch University, 2022.
Keywords
Abnormalities, Human -- South Africa, Radiography, Medical -- Positioning -- South Africa, Abnormalities, Human -- South Africa, UCTD