Characterization of Markers of Connective Tissue Degradation in Bone of Men and Women undergoing Lumbar Spine Fusion Surgery

Abstract

Bone fragility may result in devastating complications after orthopedic procedures in the spine; therefore, it is important to assess bone fragility prior to surgery. Fragility may arise from inadequate bone quantity or bone quality, such as the extent of crosslinking of bone collagen. However, a bone biopsy is required to assess collagen crosslinks in bone, such as advanced glycation endproducts (AGEs), thereby limiting preoperative assessment. Therefore, there is growing interest in a non-invasive assessment of bone quality. In this study, we compared metrics of collagen aging across skin and bone in individuals undergoing spine fusion to investigate how collagen aging in the bone may correlate with tissue aging assessed non-invasively using ultrasound in the skin. The results demonstrated that subcutaneous echogenicity in the skin increased with fluorescent AGE concentration assessed by confocal microscopy in the bone. This finding reflects that collagen may degrade in parallel across skin and bone. Thus, the use of dermal measurements assessed by ultrasound may be a promising non-invasive methodology to assess tissue degradation and predict bone quality in spine surgery patients.