Bioresorbable plate fracture after cranioplasty caused by head injury: a pediatric case

BACKGROUND: Recently, bone fixation materials have been developed as surgical materials. Bioabsorbable materials offer several advantages over other materials and are widely used. We report a rare case of the fracture of bioresorbable plates caused by head injury and describe some considerations. CASE DESCRIPTION: A 6-year-old boy suffered from consciousness disturbance. He was admitted to our hospital and diagnosed with left frontal subcortical hemorrhage due to ruptured arteriovenous malformation (AVM). He received the surgery of removal of the AVM with decompressive craniectomy. He was discharged without any neurologic deficit and underwent the cranioplasty 4 months after the initial surgery. Two months after the last treatment, he was fallen and hit his left frontal head. The next day, he noticed an abnormal bulge in the injured area. We diagnosed the bulging as cerebrospinal fluid leakage because of the dural tear. The repairment of dural tear was performed. We found that two bioresorbable plates used by cranioplasty were both cracked, and the dura mater beneath them was torn. We repaired the damaged dura with an artificial dura mater. After surgery, cerebrospinal fluid leakage did not occur. CONCLUSION: It has been reported that the durability of bioresorbable plates is no less than that of titanium plates. We experienced a relatively rare case in which bioabsorbable plate used for bone fixation was damaged due to head trauma. After craniotomy or cranioplasty using bioresorbable plates, special attention should be paid to head trauma that involves bone flap sinking force and side bending stress.