Analysis of Frontal and Orbital Osteotomy Fixation Using a Novel Adhesive Resorbable Plating System for Craniofacial Reconstruction
Jeffrey Weinzweig, MD1, Jeffrey Manchio, MD1, Shawkat Sati, MD1, Sonu Jain, MD1, Kip Panter, PhD2, Qian Wu, MD1, Anshuman Shrivastava, PhD3, Stephen McCarthy, PhD3.
1Lahey Clinic, Burlington, MA, USA, 2USDA, Logan, UT, USA, 3University of Massachusetts, Lowell, MA, USA.
Purpose: The ideal system for fixation of the pediatric craniofacial skeleton would (1) provide adequate bony stabilization, (2) resorb rapidly, (3) be low profile, (4) have bioactive modules, and (5) be user-friendly without the need for drilling equipment. To date, no existing system currently fulfills any of these criteria other than the first. The purpose of this study is to introduce a novel adhesive resorbable plating system for craniofacial reconstruction that is capable of fulfilling each of these criteria and potentially revolutionizing the fields of craniofacial surgery and neurosurgery.
Methods: A novel biodegradable polymer blend consisting of an 80:20 combination of a polylactic acid-based polymer and a polyester co-polymer was used to develop a 1.5 mm adhesive resorbable plating system. A biodegradable polyester compound serves as an adhesive for this plating system, obviating the need for screws. In vitro studies demonstrate superior tensile and mechanical properties, as well as excellent biodegradability and aging properties compared with polylactic acid (PLA) and other similar polymers used in existing plating systems. The PLA-polyester blend adhesive is thermally malleable and is alone capable of providing craniotomy fixation without the need for drills and screws.
Bilateral frontal bone osteotomies (3 cm x 1 cm) and orbital rim osteotomies (1.25 cm x 0.75 cm) were performed in nine groups of four 6-week-old goats. Bone graft fixation was performed by three resorbable methods: (1) plates + adhesive; (2) adhesive alone; (3) conventional plates + screws (control). Plates were easily contoured to the bone with warming; adhesive was applied using a heating element at 60°C that permitted adherence within 5-10 seconds following application. The adhesive alone was applied in a similar manner and adapted over the osteotomies to secure the osteotomy segments. Conventional resorbable fixation with screws and plates was used as a control. Animals in each group were harvested 6 weeks, 3 months and 6 months post-operatively; specimens were evaluated histologically, biomechanically, and histomorphometrically. Efficacy of operative time, bony fixation, and rapidity of polymer resorption of the novel systems were compared with the conventional system, which served as a control.
Results: Operative times were significantly reduced in the plates + adhesive and adhesive alone groups compared with the conventional system. The conventional technique required 4x the amount of operative time required by the adhesive alone technique and 2x that required by the plates + adhesive technique.
Excellent bony fixation and healing were achieved in all groups at each of the time points. Specimens treated with the adhesive alone demonstrated significantly greater breaking strength at the osteotomy sites compared with the other systems.
Conclusion: This innovative adhesive resorbable plating system and the resorbable adhesive are both effective in providing adequate bony fixation of the craniofacial skeleton and facilitating bony healing. Current studies are evaluating the efficacy of additional modules of this novel system including a 0.5 mm plate as well as a bioactive plate impregnated with nanospheres containing BMP and other growth factors. These novel products have the potential to revolutionize the fields of craniofacial surgery and neurosurgery.