Radiographic assessment of bone formation in tibia during distraction osteogenesis.
ABSTRACT The radiologic appearance of bone formation during limb lengthening is used to judge the competence of the underlying biologic process and predict the likely time to healing. Interpretation is, however, based upon subjective parameters that have never been clearly defined. Thirty anteroposterior radiographs from pediatric tibial lengthenings were classified by four pairs of surgeons using a three-part system. Across the group, interobserver consistency showed considerable variation for all parameters tested. Pairwise analysis indicated that the surgeons directly involved in limb lengthening procedures agreed better than those whose practice was of a different nature. A second series of radiographs contained 12 radiographs with a satisfactory and 12 with a poor bone healing index (BHI). These radiographs were digitized, and an interobserver study showed significantly improved observer concordance if the images were enhanced. No feature was associated with a 100% chance of a satisfactory outcome, but certain appearances in the regenerate were associated with a better BHI than others.
Article: "Asymmetric scalloping of the regenerate": a radiological sign of pseudoaneurysm in distraction osteogenesis.[show abstract] [hide abstract]
ABSTRACT: Pseudoaneurysm formation is an uncommon but well-recognised and important complication in limb reconstruction surgery. Postoperative diagnosis is usually clinical or an incidental finding. We present an 11-year-old girl, who underwent two-stage limb lengthening with a circular fixator, for a previously treated pseudoarthrosis of the tibia. During the lengthening plan, a concave defect was noted on one side of the regenerate, which was found to be due to extrinsic compression by a pseudoaneurysm. Normal regenerate formation was seen after selective embolisation of the pseudoaneurysm. This concave appearance on one side of the regenerate has previously been described secondary to a difference in stability on the two sides of the osteotomy, when a monolateral fixator is used, but not due to extrinsic compression by a pseudoaneurysm. The authors propose that this radiographic appearance of "asymmetrical scalloping" on one side of the regenerate may represent a radiological sign of a pseudoaneurysm formation and should provoke investigation for the same.Strategies in Trauma and Limb Reconstruction 11/2011; 6(3):159-62.