Percutaneous epiphysiodesis using transphyseal
screws (PETS) has been developed for the treatment of lower limb discrepancies
with the aim of replacing traditional open procedures. The goal
of this study was to evaluate its efficacy and safety at skeletal
maturity. A total of 45 consecutive patients with a mean skeletal
age of 12.7 years (8.5 to 15) were included and followed until maturity.
The mean efficacy of the femoral epiphysiodesis was 35% (14% to 87%)
at six months and 66% (21% to 100%) at maturity. The mean efficacy
of the tibial epiphysiodesis was 46% (18% to 73%) at six months
and 66% (25% to 100%) at maturity. In both groups of patients the
under-correction was significantly reduced between six months post-operatively
and skeletal maturity. The overall rate of revision was 18% (eight
patients), and seven of these revisions (87.5%) involved the tibia.
This series showed that use of the PETS technique in the femur was
safe, but that its use in the tibia was associated with a significant
rate of complications, including a valgus deformity in nine patients
(20%), leading us to abandon it in the tibia. The arrest of growth
was delayed and the final loss of growth at maturity was only 66%
of that predicted pre-operatively. This should be taken into account
in the pre-operative planning.
Permanent growth arrest of the longer bone is
an option in the treatment of minor leg-length discrepancies. The
use of a tension band plating technique to produce a temporary epiphysiodesis
is appealing as it avoids the need for accurate timing of the procedure
in relation to remaining growth. We performed an animal study to
establish if control of growth in a long bone is possible with tension
band plating. Animals (pigs) were randomised to temporary epiphysiodesis
on either the right or left tibia. Implants were removed after ten
weeks. Both tibiae were examined using MRI at baseline, and after
ten and 15 weeks. The median interphyseal distance was significantly shorter
on the treated tibiae after both ten weeks (p = 0.04) and 15 weeks
(p = 0.04). On T1-weighted images the metaphyseal water
content was significantly reduced after ten weeks on the treated
side (p = 0.04) but returned to values comparable with the untreated
side at 15 weeks (p = 0.14). Return of growth was observed in all
animals after removal of implants. Temporary epiphysiodesis can be obtained using tension band plating.
The technique is not yet in common clinical practice but might avoid
the need for the accurate timing of epiphysiodesis. Cite this article:
