Resident Physician University of Minnesota Medical School Bloomington, Minnesota, United States
Case Diagnosis: Sinking Skin Flap Syndrome (SSFS)
Case Description: A 34 year old male presented after being found down in the setting of alcohol intoxication. CT head revealed multicompartmental intracranial hemorrhages with 3mm midline shift requiring emergent decompressive craniectomy. Post-op course was complicated by high intracranial pressures (ICP), eventually leading to VP shunt placement. Patient was admitted to rehab for left hemiparesis and cognitive deficits. Patient progressed to ambulation on uneven outdoor terrain with contact guard assist. However, on post-op day 27, the patient experienced severe lethargy and ataxia, limiting ambulation ability. Head CT demonstrated new concavity along the flap surface and left midline shift concerning for paradoxical herniation. Patient was transferred to the SICU and mental status/cognition rapidly improved after Trendelenburg positioning and VP shunt clamping. Patient was diagnosed with SSFS and returned to acute rehab within 2 days, yet lost prior functional gains due to worsened hemiparesis and persistent truncal instability. Patient underwent cranioplasty several weeks later.
Discussions: This case demonstrates the rare craniectomy complication of SSFS along with the exacerbating risk factor of concurrent CSF diversion from a VP shunt. A hallmark of SSFS is the reversal of neurologic deterioration following emergent cranioplasty, reducing atmospheric compression on the flap site with resolution of midline shift. Cranioplasty is the definitive treatment but is often delayed to allow for stabilization of ICP. In this case, simple, low fidelity measures of Trendelenburg positioning and cessation of VP shunting increased the ICP to overcome the shifting caused by atmospheric pressure at the flap site, causing symptom reversal and avoiding emergent cranioplasty. However the extent of neurologic injury contributed to sustained functional losses.
Conclusions: SSFS is a rare complication following craniectomy. Early recognition is crucial to promptly increase ICP and reverse symptoms. However, this additional neurologic insult can lead to lasting loss of functional rehabilitation progress.
