Cranial Nerves
 

Jaw Jerk

 
 
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On this page:Jaw Jerk Pathway

Overview

  • The jaw jerk is also known as the masseter inhibitory reflex; it involves the mandibular branch of the trigeminal nerve as both its afferent and efferent arms.

    • How to Elicit

    • Place a finger horizontally over the chin with the mouth open, and then strike this finger with a tendon hammer. 
  • Warn the patient beforehand!
  • While a slight jerk may be normal, an exaggerated jerk is a sign of an upper motor neuron lesion.

    • Interpretation

    • Slight / absent jerkNormal, mandibular nerve (V3) lesion
    • Exaggerated jerk (± clonus)Upper motor neuron lesion

Jaw Jerk Pathway

  • Receptors
    Muscle spindle within mandible
     
     
    Foramen
    Foramen ovale
    V3
    Mandibular branch
     
    Trigeminal Ganglion
     
     
    Mesencephalic nucleus
    Midbrain, pons
     
     
    Trigeminal Motor Nucleus
    Upper pons
     
    V3
    Mandibular branch
    Foramen
    Foramen ovale
     
     
    Muscle
    Masseter
Last updated on February 4th, 2020
 
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 Acierno M. Ophthalmoscopy for the Neurologist. The Neurologist. 2001 Jul; 7(4): 234-251. Adhab R, Saade HS, Kikano R, Ferzli J, Tarcha W, Riachi N. Pure ipsilateral central facial palsy and contralateral hemiparesis secondary to ventro-medial medullary stroke. Journal of the Neurological Sciences. 2013; 332: 154-155. Ahmad K, Wright M, Lueck CJ. Ptosis. Practical Neurology. 2011; 11: 332-340. Anderson DR. Standard Perimetry. Ophthalmol Clin N Am  2003;16: 205-212. Armaly MF. The size and location of the normal blind spot. Arch Ophthalmol. 1969; 81(2):192-201. Athanasiov PA. Prabhakaran VC, Selva D. Non-traumatic Enophthalmos: a Review. Acta Ophthalmologica. 2008 June; 86(4): 356-364. Bagheri A, Fallahi M, Abrishami M, Salour H, Aletaha M. Clinical features and outcomes of treatment for fourth nerve palsy. Journal of ophthalmic & vision research. 2010;5:27-31. Bhargava A, Banakar BF, Pujar GS, Khichar S. A study of Guillain-Barré syndrome with reference to cranial neuropathy and its prognostic implication. Journal of neurosciences in rural practice. 2014;5:S43-S47. Bolanos I, Lozano D, Cantu C. Internuclear ophthalmoplegia: causes and long?term follow?up in 65 patients. Acta neurologica scandinavica. 2004 Sep;110(3):161-5. Bussell MA, Heady J. Unexpected Quinsy. British Dental Journal. 2007; 203: 227-228. Castiglia PT. Strabismus. Journal of Paediatric Health Care. 1994; 8: 236-238.
Chen G, Wang X, Wang L, Zheng J. Arterial compression of nerve is the primary cause of trigeminal neuralgia. Neurological Sciences. 2014;2013;35:61-66.
 Childs SG. Muscle Wasting. Orthopaedic Nursing. 2003; 22(4): 251-257.
Dacso CC, Bortz DL. Significance of the Argyll Robertson pupil in clinical medicine. The American journal of medicine. 1989 Jan 1;86(2):199-202.
 Danchaivijitr C, Kennard C. Diplopia and Eye Movement Disorders. J Neurol Neurosurg Psychiatry. 2004; 75: 24-31. Daniels SK. Neurological Disorders Affecting Oral, Pharyngeal Swallowing. GI Motility online. 2006. Available from: http://www.nature.com/gimo/contents/pt1/full/gimo34.html. Davidson TM, Jalowayski A, Murphy C, Jacobs RD. Evaluation and Treatment of Smell Dysfunction. The Western Journal of Medicine. 1987 April; 146(4): 434-438. De Foer B, Kenis C, Van Melkebeke D, et al. Pathology of the vestibulocochlear nerve. European Journal of Radiology. 2010;74:349-358. Desai J, Swash M. Fasciculations: What Do We Know of Their Significance?, Journal of Neurological Sciences. 1997; 152 S1: S43-S48. Fiore DC. Pain in the Quiet (Not Red) Eye. American Family Physician. 82(1): 69-72. Gaddipati RV, Meyer DR. Eyelid Retraction, Lid Lag, Lagophthalmos, and Von Graefe’s Sign: Quantifying the Eyelid Features of Grave’s Ophthalmopathy. Ophthalmology 2008. 115: 1083-1088. Gates P. The rule of 4 of the brainstem: a simplified method for understanding brainstem anatomy and brainstem vascular syndromes for the non?neurologist. Internal medicine journal. 2005 Apr;35(4):263-6. Gattey D. The Pupil Examination in the Trauma Patient. Journal of Emergency Nursing. 2004 Oct; 30(5): 512-513. Gottlob I. Nystagmus. Current Opinion in Ophthalmology. 2001; 12: 378-383. Granick MS, Martuza RL, Ojemann RG, Parker SW, Montgomery WW. Cerebellopontine angle meningiomas: clinical manifestations and diagnosis. Annals of Otology, Rhinology & Laryngology. 1985 Jan;94(1):34-8.
Grieg MH. Otoscopy for the GP. Current Therapeutics. 1999; 40(6): 79-87.
 Hardy LG, Rand G, Rittler MC. Tests for Detection and Analysis of Color Blindness I: An Evaluation of the Ishihara Test. Arch Ophthalmol. 1945: 34(4): 295-302. Haslam RH. Clinical neurological examination of infants and children. Handb Clin Neurol. 2013; 111: 17-25. Haughton PM, Pearce JM. Observations on the Rinne Test. Lancet. 1982 April; 8276(319): 829-830. Idro R, Otieno B, White S, Kahindi A, Fegan G, Ogutu B et al. Decorticate, Decerebrate and Opisthotonic Posturing and seizures in Kenyan Children with Cerebral Malaria. Malaria Journal. 2005; 4(57). Isaacson B. Hearing Loss. Medical Clinics of North America. 2010 Sept; 94(5): 973-988.
Jäger HR, Miszkiel KA. Pathology of the optic nerve. Neuroimaging clinics of North America. 2008;18:243-259.
 Jolles J, Houx PJ, Verhey FRJ, Vreeling FW. Primitive reflexes in Parkinson's disease. Journal of neurology, neurosurgery and psychiatry. 1993;56:1323-1326. Jung WS, Kwon SW, Park SU, Moon SK, Park JM, Ko CN et al. Electroacupuncture for Decorticate Rigidity of the Upper Limbs in a Patient with Anoxic Brain Damage. Case Reports in Medicine. 2013; 1-4. Kannikeswaran N, Mahajan PV, Kamat D. Acute Facial Symmetry. Clinical Paediatrics. 2006; 45: 289-292. Kawasaki A. Anisocoria. Neuro-Ophthalmology. 2009 Aug; 15(4): 218-235. Keane JR. Internuclear ophthalmoplegia: unusual causes in 114 of 410 patients. Archives of neurology. 2005 May 1;62(5):714-7. Keane JR. Twelfth-nerve palsy: analysis of 100 cases. Archives of neurology. 1996 Jun 1;53(6):561-6. Keane JR. Vertical Diplopia. Seminars in Neurology. 2008;6:147-154. Kiely PM, Kowal L. Review of Facial Muscle Spasms. Clinical and Experimental Optometry. 1997; 80(2): 59-61. Kieser JA. Anatomical Knowledge and Clinical Evaluation of the Muscles of Mastication. Clinical Anatomy. 2000; 13(2): 94-96. Lee AG, Al-Zubidi N, Beaver HA, Brazis PW. An Update on Eye Pain for the Neurologist. Neurologic Clinics. 2014 May; 32(2): 489-505.
Levenson JH, Kozarsky A. Visual Acuity Change. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Chapter 111.
 Liebman SD. Strabismus. New England Journal of Medicine. 1964; 271: 1258-1260. Lima MA, Maranhao-Filho P. What is the essential neurological examination? Arq Neuropsiquiatr 2012; 70(12): 939-941. Lueck CJ. Nystagmus. Practical Neurology. 2005 Oct; 288-291. Lyden P. The Endovascular Procedure-Specific Neurological Examination Scheme. J Endovasc Ther. 2011; 18: 538–539. Lynch GS, Schertzer JD, Ryall JG. Therapeutic Approaches for Muscle Wasting Disorders. Pharmacology and Therapeutics. 2007 Mar; 113(3): 461-487. Manon-Espaillat R, Ruff RL. Dissociated weakness of sternocleidomastoid and trapezius muscles with lesions in the CNS. Neurology. 1988; 38: 796–797. Merino PS, Rojas PL, Gómez De Liaño, Pilar S, Fukumitsu HM, Yáñez JM. Bilateral superior oblique palsy: etiology and therapeutic options. European journal of ophthalmology. 2014;24:147. Moore FG, Chalk C. The essential neurologic examination: what should medical students be taught? Neurology. 2009; 72: 2020-2023. Moylan JS, Reid MB. Oxidative Stress, Chronic Disease and Muscle Wasting. Muscle & Nerve. 2007; 35:411-429. Nadol JB. Hearing Loss. New England Journal of Medicine. 1993; 329: 1092-1102. Nicolson SE, Chabon B, Larsen KA, Kelly SE, Potter AW, Stern TA. Primitive reflexes associated with delirium: a prospective trial. Psychosomatics. 2011;52:507. Obuchowska I, Mariak Z. Homonymous hemianopsia. Klinika oczna. 2012;114:226. Ongerboer de Visser BW, Moffie D. Effects of Brain-Stem and Thalamic Lesions on the Corneal Reflex: An Electrophysiological and Anatomical Study. Brain. 1979; 102: 595-608. Park U, Kim S, Hwang J, Yu YS. Clinical features and natural history of acquired third, fourth, and sixth cranial nerve palsy. Eye. 2008;22:691-696. Parry LA. Hemiatrophy of the Tongue. Lancet. 1900 Feb: 537. Perkin GD. Neuro-ophthalmological syndromes for neurologists. Journal of Neurology, Neurosurgery & Psychiatry. 2004 Dec 1;75(suppl 4):iv20-3. Pierrot-Deseilligny C, Milea D. Vertical Nystagmus: Clinical Facts and Hypotheses. Brain. 2005 Jun; 128(6): 1237-1246. Poppen JL. Exophthalmos. The American Journal of Surgery. 1944; 64(1): 64-79. Rainsbury JW, Aldren CP. Facial Nerve Palsy. Clinical Otolaryngology. 2007 Feb; 32(1): 38-40. Sanders RD, Gillig PM. Cranial nerve I: olfaction. Psychiatry (Edgmont (Pa. : Township)). 2009;6:30. Sharshar T, Citerio G, Andrews PJ, Chieregato A, Latronico N, Menon DK, Puybasset L, Sandroni C, Stevens RD. Neurological examination of critically ill patients: a pragmatic approach. Report of an ESICM expert panel. Intensive Care Med. 2014 Feb.  Smith SA, Smith SE. Bilateral Horner's syndrome: detection and occurrence. Journal of neurology, neurosurgery, and psychiatry. 1999;66:48-51. Stahl JS, Leigh RH. Nystagmus. Current Neurology and Neuroscience Reports. 2001; 1: 471-477. Thompson EO, Smoker WR. Hypoglossal nerve palsy: a segmental approach. Radiographics. 1994 Sep;14(5):939-58.
Thompson HS, Kardon RH. The argyll robertson pupil. Journal of neuro-ophthalmology. 2006 Jun 1;26(2):134-8.
 Thompson HS. Adie's syndrome: some new observations. Transactions of the American Ophthalmological Society. 1977;75:587. Timmis P. Exophthalmos. Journal of Otolaryngology and Otology. 1957 Nov; 71(11): 744-753. Tomczak KK, Rosman NP. Torticollis. J Child Neurol. 2013 March; 28(3): 365-378. Toro J, Reyes S. Tongue Fasciculationsin Amyotrophic Lateral Sclerosis. NEJM. 2014 Jul; 371(5). Toulgoat F, Sarrazin JL, Benoudiba F, et al. Facial nerve: from anatomy to pathology. Diagnostic and interventional imaging. 2013;94:1033-1042. Vilensky JA. The neglected cranial nerve: Nervus terminalis (cranial nerve N). Clinical Anatomy. 2014;27:46-53. Virgo JD, Plant GT. Internuclear ophthalmoplegia. Practical neurology. 2017 Apr 1;17(2):149-53.
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