DOS 2016

DOS Kongressen 2016 ·

Calcaneal cuboid joint motion can be assessed by

radiostereometric analysis

Polina Martinkevich, Maiken Stilling , Bjarne Møller-Madsen, Ole Rahbek

Paediatric Ortopaedics, Aarhus University Hospital

Background:

Subluxation in the calcaneo-cuboid joint (CCJ) with dorsal dis-

placement of the anterior calcaneal fragment following a calcaneal lengthening

osteotomy in children is a frequently observed finding. Various methods to quan-

tify the displacement have been proposed using conventional X-rays. However

these methods are unprecise and only allow for uniplanar measurement.

Purpose / Aim of Study:

We investigated the feasibility of using marker-

based radiostereometric analysis (RSA) for measurements of the CCJ in pediat-

ric patients who underwent calcaneal lengthening surgery for flexible flatfoot.

Materials and Methods:

Eight patients diagnosed with flexible flatfoot (8 feet;

1 male, 7 females) with mean age 12.3 years (range 8.2-14.2) were examined

one year after calcaneal lengthening osteotomy (CLO). Supine and standing ste-

reoradiographs were obtained. The Oxford ankle foot questionnaire (OxAFQ)

was used to assess the affect of the foot on the quality of life of the child.

Findings / Results:

Precision of the RSA measurements of the CCJ ranged be-

tween 0.14-0.58 mm for translations and 2.08-4.26 degrees for rotations. In

response to loading we find the cuboid to translate (mean; range) distally by

-0.92 mm(-1.78;-0.12), dorsally by 2.13 mm(0.58;4.07), laterally by -1.94

mm(-3.94;-0.17) and rotate medially around the x-axis by 7.23 degrees

(-1.05;17.06) with reference to the distal calcaneal fragment. Based on the

OxAFQ scores children were asymptomatic.

Conclusions:

This is the first in vivo study describing the CCJ kinematics in chil-

dren one year after CLO using RSA. This is the first step towards understanding

the CCJ before and after CLO, and to examine the clinical consequences of this

motion. In the future, model-based RSA and fluoroscopy can allow for obtaining

preoperative models of the foot and provide a complete kinematic analysis of

the CCJ during motion.

No conflicts of interest reported

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