John Peter Gruen, MD

Clinical Associate Professor of Neurological Surgery (Part-Time)

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Dr. John Peter Gruen, a highly esteemed Professor of Medicine at the University of Southern California (USC), stands at the forefront of neurosurgery with a particular focus on neurotrauma. He brings a remarkable blend of experience, skill, and dedication to his role, reflected in his substantial contributions to both clinical practice and academic medicine.

Dr. Gruen’s academic journey is marked by an impressive educational background, holding degrees from Yale College (BA in History), Columbia University (MD in Medicine), and having completed extensive research and fellowships in neuroscience and nerve surgery at prestigious institutions including the University of Southern California and Gunzberg Hospital in Germany.

In his illustrious career, Dr. Gruen has held several key positions, including Associate Medical Director of Critical Care at the Los Angeles General Medical Center (LAGMC), Medical Director of Utilization Review at LAGMC, and Associate Clinical Professor of Neurosurgery at Keck USC School of Medicine. His expertise in neurosurgical care, especially in treating traumatic brain injuries (TBI), is widely recognized.

Dr. Gruen’s dedication to community health is evident in his establishment of the LAC+USC Brain Injury Clinic, which addresses the long-term sequelae of TBI and expanded to include care for COVID-19 long-haul patients. His commitment to educating and supporting those suffering from chronic conditions underlines his holistic approach to patient care.

As a clinician, educator, and researcher, Dr. Gruen has made significant contributions to the field, including involvement in interventional clinical trials for TBI and publishing in renowned journals. His work in underserved hospitals highlights his dedication to improving outcomes in challenging healthcare environments.

Dr. Gruen’s unwavering commitment to neurosurgical innovation and patient-centered care makes him an invaluable asset to the USC Neurosurgery team.


  • No More ‘Code Black’: Intervention to Improve Inpatient Flow at a Large Public Hospital Am J Med. 2018 04; 131(4):371-376. . View in PubMed
  • Safety-net versus private hospital setting for brain metastasis patients treated with radiosurgery alone: Disparities in follow-up care and outcomes Cancer. 2018 Jan 01; 124(1):167-175. . View in PubMed
  • Decreased mortality in patients with isolated severe blunt traumatic brain injury receiving higher plasma to packed red blood cells transfusion ratios Injury. 2018 Jan; 49(1):62-66. . View in PubMed
  • Introduction: Adult hydrocephalus Neurosurg Focus. 2016 Sep; 41(3):E1. . View in PubMed
  • Compliance With Evidence-Based Guidelines and Interhospital Variation in Mortality for Patients With Severe Traumatic Brain Injury JAMA Surg. 2015 Oct; 150(10):965-72. . View in PubMed
  • Intracranial pressure monitoring and inpatient mortality in severe traumatic brain injury: A propensity score-matched analysis J Trauma Acute Care Surg. 2015 Mar; 78(3):492-501; discussion 501-2. . View in PubMed
  • Decompressive craniectomy: surgical control of traumatic intracranial hypertension may improve outcome Injury. 2010 Sep; 41(9):894-8. . View in PubMed
  • Infrared thermal imaging: a review of the literature and case report Neuroimage. 2009 Aug; 47 Suppl 2:T154-62. . View in PubMed
  • Hemodynamic and oxygen transport patterns after head trauma and brain death: implications for management of the organ donor J Trauma. 2007 Nov; 63(5):1032-42. . View in PubMed
  • Survival, hemodynamics, and tissue oxygenation after head trauma J Am Coll Surg. 2006 Jan; 202(1):120-30. . View in PubMed
  • Minimally invasive lateral mass screws in the treatment of cervical facet dislocations: technical note Neurosurgery. 2003 Feb; 52(2):444-7; discussion 447-8. . View in PubMed
  • Brain death documentation: analysis and issues Neurosurgery. 2002 Sep; 51(3):731-5; discussion 735-6. . View in PubMed
  • Brachial plexus catheter reservoir for the treatment of upper-extremity cancer pain: technical case report Neurosurgery. 2000 Apr; 46(4):1009-12. . View in PubMed
  • Resection and graft repair for localized hypertrophic neuropathy Neurosurgery. 1998 Jul; 43(1):78-83. . View in PubMed
  • Continuous use of standard process audit filters has limited value in an established trauma system J Trauma. 1996 Sep; 41(3):389-94; discussion 394-5. . View in PubMed
  • Management of complicated neurologic injuries Surg Clin North Am. 1996 Aug; 76(4):905-22. . View in PubMed
  • Evaluation and management of spondylolysis and spondylolisthesis Clin Neurosurg. 1993; 40:384-415. . View in PubMed