Article

OBJECTIVE: To evaluate the response of bone to 2 anabolic stimuli, teriparatide
and mechanical loading, in subjects with spinal cord injury.
DESIGN : A pilot study, 1 group, pretest-posttest. SETTING:
A rehabilitation hospital.
PARTICIPANTS: A convenience sample of 12 nonambulatory chronic spinal cord injury
subjects. METHODS: The subjects were administered open-label teriparatide 20
mug/d while undergoing robotic-assisted stepping 3 times a week for 6 months,
followed by 6 months of teriparatide alone. MAIN OUTCOME MEASUREMENTS: Bone
status was evaluated at 3, 6, and 12 months by using dual-energy x-ray
absorptiometry to calculate bone mineral density (BMD) at the spine and hip,
magnetic resonance imaging to assess bone microarchitecture of the distal tibia,
and serum bone markers. RESULTS: Mean (SD) baseline BMD measurements at the spine
and the left and right total hip were 1.05 +/- 0.162 g/cm(2), 0.638 +/- 0.090
g/cm(2) and 0.626 +/- 0.088 g/cm(2), respectively. After 6 months of treatment,
BMD changed 2.19% +/- 3.61%, 0.02% +/- 2.21%, and 0.74% +/- 2.80% at the spine,
and left and right total hip, respectively. These changes were not statistically
significant (P > .05 for all). Magnetic resonance imaging supported an anabolic
effect after 3 months of treatment with significant (P < .05) changes in
trabecular thickness, 4.4% +/- 4.06%; surface-to-curve ratio, 23.6% +/- 22.3%;
and erosion index, -17.04% +/- 12.9%. Although the trend remained after 6 months,
statistical significance was not retained. At 6 months, bone markers indicated an
increase in mean levels of bone-specific alkaline phosphatase, 53.8% +/- 62.9%;
C-terminal telopeptides of type I collagen, 137.6% +/- 194.6%; and intact
amino-terminal propeptide of type I procollagen, 61.4% +/- 99.3%. CONCLUSION: In
this limited pilot study, teriparatide and mechanical loading resulted in a
numerical but not statistically significant increase in lumbar spine BMD and no
significant BMD changes at the hip. Magnetic resonance imaging at the distal
tibia suggested an anabolic effect, but the high sensitivity offered by this
technique was challenged by the limited ability to obtain analyzable data from
all the subjects. Further studies that involve longer treatment periods and
greater mechanical loading are warranted.
CI - Copyright (c) 2013 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS