Biodegradable temporizing matrix in the management of exposed cortical bone without periosteum: a flap-sparing and reproducible strategy

Background Exposure of cortical bone without periosteum (CBWP) represent a complex wound with poor healing potential, regardless of its location. Coverage traditionally relies on flaps, a complex reconstruction procedure. The use of a synthetic biodegradable dermal matrix (Novosorb® BTM) may promote formation of a vascularized neodermis over cortical bone, allowing subsequent skin grafting or secondary healing. This study aims to evaluate the effectiveness and limitations of synthetic dermal matrix in covering CBWP, potentially redefining flap indications. Methods We conducted a retrospective single-center study including consecutive patients presenting CBWP exposure, regardless of etiology or anatomical site, over a one-year period. Management followed a standardized staged protocol: Surgical debridement ± cortical bone preparation, secure application of Novosorb®, delamination upon homogeneous neodermis formation, followed by split-thickness skin grafting (STSG) or secondary epithelialization. Primary outcomes were complete epithelialization and time-to-event. Results 19 patients with 22 defects (scalp n=14, face n=2, tibia n=5, chest wall n=1) were treated with this protocol. Complete healing was achieved in 17 cases (10 by secondary epithelialization, 7 by STSG). Median time to grafting readiness was 37.5 days, and median time to complete healing was 65 days. We identified major complication rate in 4 (flap conversion in 2), and minor complications in 2 cases. At 6 months, all successfully treated wounds remained stable with satisfying functional and aesthetic outcomes. Conclusions A staged synthetic dermal matrix (Novosorb® BTM) protocol reliably converts CBWP into a vascularized wound bed suitable for STSG or secondary epithelialization, by promoting neovascularization and granulation tissue formation. It offers temporal predictability and reduces the need for flap reconstruction in selected complex cases.