Penetrating brain injury with a bike key: a case report.

Penetrating brain injury (PBI) may be caused by low-velocity or high-velocity objects. Several objects are known to cause such injury ranging from knives to rooster pecks. However, an assault with the key of a bike causing PBI has not been reported in the literature. The objective of this study was to report the case of a 21-year-old male patient, who presented after an assault with a bike key. The key was impacted in the left parietal region. Left parietal craniotomy was done and the key was removed. There was an underlying parenchymal contusion, which was excised. On post-operative day two, the patient developed motor aphasia, which subsided in subsequent days with antiedema measures. At the first month follow-up, the patient was having normal speech and consciousness. Prompt treatment of penetrating brain injury is important and angiography is not always necessary for PBI.