Background: Our aim was to compare height
velocity data, obtained from clinical height measurements, for girls who
had idiopathic scoliosis with the data for adolescents who did not
have scoliosis. We also compared the growth data with chronological
age, menarchal age, and Risser sign in terms of their accuracy in
the prediction of growth and progression of the scoliosis.
Methods: One hundred and twenty of 371 patients
in a database of girls managed with a brace for the treatment of
idiopathic scoliosis had sufficient height data for us to quantify
their growth peak. Height velocity data was generated from standing-height measurements
obtained, in a scoliosis clinic, with a minimum six-month interval
between measurements, and the timing of peak height velocity was calculated.
The age at menarche was recorded from the patients' records. The
Risser sign and Cobb angle were determined by a single observer. Progression
of the scoliosis was defined as an increase in the Cobb angle of
at least 10 degrees, compared with the curve magnitude at the time
of the initial evaluation, after a minimum of six months. Progression
to a magnitude requiring surgery was defined as progression of at
least 10 degrees to a magnitude of 45 degrees or more.
Results: The height velocity plot grouped by
peak height velocity showed a high peak and a sharp decline with
values similar to those in normal populations. Extrapolating from
percentile charts, 90 percent of our patients ceased growing by
3.6 years after peak height velocity. The growth peak was blunted (averaged
over too long a period such that the data for the period of most
rapid growth was averaged in with that for a period of slower growth)
when chronological age, menarchal age, and Risser sign were used
to predict growth; this indicated that these maturity scales grouped
the patients poorly in terms of growth.
The primary curve was progressive in eighty-eight of the 120
patients. Sixty of these patients had a curve of more than 30 degrees
at peak height velocity, and in fifty (83 percent) of the sixty
the curve progressed to 45 degrees or more. The remaining twenty-eight
patients had a curve of 30 degrees or less at peak height velocity,
with only one curve (4 percent) progressing to 45 degrees or more.
Peak height velocity also grouped patients for maximal progression
of the curve more accurately than did the other maturity scales,
as most of the curves progressed maximally at peak height velocity.
There was a wider spread of timing of maximal progression when chronological
age, menarchal age, and Risser sign were used to predict progression.
Conclusions: Height velocities generated from
clinical height measurements for patients with idiopathic scoliosis
document the growth peak and predict cessation of growth reliably.
Knowing the timing of the growth peak provides valuable information
on the likelihood of progression to a magnitude requiring spinal