F. Forriol et al., Relationship between radiologic morphology of the bone lengthening formation and its complications, J PED ORT B, 8(4), 1999, pp. 292-298
The objective was to study the different types of lengthened bone regenerat
ion and their development during the various phases of the process to corre
late them with patient factors and the surgical technique used, and to esta
blish a possible relation between the development of the bone lengthening f
ormation and the problems or complications. The authors studied the radiogr
aphs of a random group of 55 patients taken at three points during the cour
se of treatment. The callus was classified with regard to its transverse di
ameter and the presence or absence of hypodense areas. The overall callus t
ype was significantly influenced by the etiology, the osteotomy site, and t
he percentage lengthened. The percentage by which the limb was lengthened a
t the beginning of the process influences the overall morphology of the cal
lus. Poor callus had been lengthened the most, atrophic callus the least. T
here was a correlation between the morphology of the overall callus at the
end of treatment and the percentage lengthened, and between the percentage
lengthened and the presence of bands at the end of treatment. The authors a
lso found a significant correlation between age and the appearance of bands
at the end of distraction. A central band was found among younger patients
. The type of osteotomy affected the overall callus at the end of distracti
on and at the end of treatment and also influenced the transverse diameter.
All the elongations with poor bone formation at the end of treatment were
found to have undergone a diaphyseal osteotomy. The most common complicatio
n at the first follow-up and at the end of distraction was angulation. The
diameter of the callus and the presence of bands at the end of treatment we
re significantly related to the complications. Fracture occurred in the fir
st 2 weeks after removal of the external fixator in 88% of cases and in the
third and fourth week in the rest. However, the segment had no significant
influence on the appearance of complications. Lengthened callus with incom
plete trabecular formations and hypodense areas at the end of the treatment
has a high risk of fracture at the end of treatment. Callus with axial dev
iation, hypodense areas, or an insufficient transverse diameter during the
lengthening procedure must be manipulated so that it reaches the maturing p
hase in better condition.