Pathophysiology
Ibrahim Natalwala, Ammar Natalwala, E Glucksman in MCQs in Neurology and Neurosurgery for Medical Students, 2022
Regarding common clinical examination signs, which of the following statements are true and which are false? Testing the bicep reflex tests the C5, C6 nerve root.The Achilles reflex tests the S4 nerve root.The Moro reflex normally disappears within the first year of life.A normal Babinski response is extensor plantar response and fanning of toes.Fasciculations are a sign of an upper motor neurone lesion.
Motor development and postural control
Michael Horvat, Ronald V. Croce, Caterina Pesce, Ashley Fallaize in Developmental and Adapted Physical Education, 2019
The Moro reflex is elicited by a sudden noise, tapping of the abdomen, or insecure position of support. Infants will first extend the fingers, abduct the arms and legs, and then adduct the limbs and flex the fingers. Persistence of the Moro reflex after 9 months interferes with the ability to sit unsupported, to assume a four-point crawling position, or to stand unsupported in a two-point position. This reflex can also interfere with locomotor patterns and sport skills requiring sudden movement. For example, in gymnastics, a fast movement may cause a loss of equilibrium while the individual performs a skill. The influence of the Moro reflex would be apparent as the arms and legs abduct, causing the loss of balance.
Primitive or baby reflexes
Jill Christmas, Rosaline Van de Weyer in Hands on Dyspraxia: Developmental Coordination Disorder, 2019
The Moro reflex is present as early as the first nine or ten weeks in the womb and is normally inhibited within two to four months in the young baby. It is elicited in response to an incoming, usually unexpected or unpleasant stimulus. It is there in part as a protective mechanism, and when stimulated can cause a whole-body movement and stress reaction in the body. In response, the baby may startle, fling their arms out to the side, bend both legs up into a flexed position, and take a large intake of breath prior to crying in a distressed manner.
Morphological basis of radial nerve dysfunction in newborns differs from that of no radial nerve dysfunction in adults in C5–C6–C7 injuries to the brachial plexus: a cadaveric study
Published in British Journal of Neurosurgery, 2021
Jiayu Sun, Liang Chen, Shaonan Hu, Jie Song, Jixin Wu, Yudong Gu
In the development of infant’s motor function of the upper extremity, there exists at birth the motion of the shoulder and elbow, such as the Moro reflex which is mostly innervated by the upper and middle trunks of the brachial plexus.15 However, fine, harmonious movements of the hand that are innervated by the lower trunk of the brachial plexus do not appear until 10–12 months after birth.16 This suggests that in newborns, the lower trunk of the plexus may be less developed functionally as compared to the middle and upper trunks. It was found in most species that at the early stage post-natal, together with neuron apoptosis, new neurons can be produced to participate in nervous system development.17 In adulthood of rodents, neural precursor cells in the spinal cord can still proliferate and differentiate to perform peripheral nerve function.18 These findings suggest that the postnatal development of human peripheral nerves not only experience a process of fabric maturity, but have the plasticity in the number of neurons.
İpsilateral clavicle and humerus diaphysis fractures in newborn after vaginal delivery; a very rare case report
Published in Journal of Obstetrics and Gynaecology, 2022
Metin Celik, Emre Arikan, Sevil Eraslan, Songul Celik Tastan
Failure to take the moro reflex in the postnatal examination of the newborn may first suggest a brachialplexus injury. However, accompanying clavicle fracture and/or humerus fracture is another cause of the moro reflex that cannot be removed. In these patients, the moro reflex is taken at an earlier stage. Neonatal fractures can be encountered in all delivery methods and manoeuvres. Therefore, early detection of such traumas is very important; acomprehensive examination and evaluation is essential in the early period after birth. Differential diagnoses should be considered, and high suspicion should be raised.