Bone adaptation of a biologically reconstructed femur after Ewing sarcoma: Long-term morphological and densitometric evolution
Combining bone allografts and vascularized fibular autografts in intercalary reconstructions after resection of bone sarcomas is of particular interest in young patients as it facilitates bone healing and union and helps reduce fractures. However, adverse events related to bone adaptation still occur. Bone adaptation is driven by mechanical loading, but no quantitative biomechanical studies exist that would help surgical planning and rehabilitation. We analyzed the bone adaptation of a successful femoral reconstruction after Ewing sarcoma during 76-month follow-up using a novel methodology that allows CT-based quantification of morphology and density. The results indicated that the vital allograft promoted bone adaptation in the reconstruction. However, an overall negative balance of bone remodeling and a progressive mineral density decrease in the femoral neck might threaten long-term bone safety. These concerns seem related to both surgical technique and mechanical stimuli, where a stiff metal implant may determine load sharing, which negatively affects bone remodeling.
KeywordsBiological reconstruction Bone sarcoma Bone adaptation Biomechanical measurements Bone mineral density
The authors are grateful to Sabina Piroddi for her contribution to the measurement methodology. This study was supported by the project “Biological bone reconstruction in children skeleton after sarcoma resection. Validation of the technique through CT scan analysis and histological evaluation of the retrieved cases” (RF-2010-2321501), funded by the Italian Ministry of Health, and the National Program of donations to research “5 per mille” 2013.
Compliance with ethical standards
Conflicts of interest
The authors declare that they have no conflicts of interest.
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