Cervico-Collic Reflex
Introduction
This stretch reflex is one of cervical reflexes that has been studied among animals but its role in humans are still uncertain[1]. Clinicians usually examine the reflex arc integrity for different patient conditions that may involve central nervous system or neck muscles.
Neurophysiology
Stimulus: Stretching of neck muscles (usually during body motion -not head- to one side).[2]
Afferent: Proprioceptors of neck muscles send sensory input to dorsal column of spinal cord.
Center: Cervical segments of spinal cord.
Efferent: through alpha motor neurons in spinal cord to Neck muscles.
Response: Neck muscles contraction (Stabilizing the head over trunk).[3]
Function
The function of the Cervico-collic reflex is to stabilize the head on the body and provide information about motion of the head with respect to the trunk. It is believed that sensory inputs from this reflex integrate with other reflexes e.g. vestibulo-collic, cervico-ocular and vestibulo-ocular reflexes to maintain head posture and stabilization.[4]
Examination
Tools: Flashlight over head
Instruct the patient to hold head in neutral position, mark the flashlight point on the wall. Now, turn of flash light off and instruct the patient to hold hands against waist then rotate the trunk to either sides slowly in controlled manner while keeping head still in the starting neutral position.[2]
References
- ↑ Dutia MB, Price RF. Interaction between the vestibulo-collic reflex and the cervico-collic stretch reflex in the decerebrate cat. The Journal of physiology [Internet]. 1987 Jun;387:19–30. Available from: https://pubmed.ncbi.nlm.nih.gov/3498829/
- ↑ 2.0 2.1 Dutton M. Dutton’s Orthopaedic Examination Evaluation and Intervention. Third edition. McGraw Hill Professional; 2012.
- ↑ Dolbow J, Throckmorton Z. Neuroanatomy, Spinal Cord Myotatic Reflex [Internet]. PubMed. Treasure Island (FL): StatPearls Publishing; 2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK551629/
- ↑ Renga V. Clinical Evaluation of Patients with Vestibular Dysfunction. Neurology Research International. 2019 Feb 3;2019:1–8.