Cervical Subluxation(Archived)

Spinal cord injury (SCI) accounts for multispectral neurological deficit patterns and severely compromises the dichotomous utilization of health resources, especially in low- and middle-income nations. Nearly 80% of patients with this condition are males, with almost 60% aged 16 to 30. Moreover, as many as 60% of these individuals remain unemployed following such incidents. Subluxation comprises a significant proportion of traumatic cervical spinal injuries. This condition entails varying degrees of vertebral body slippage relative to adjacent vertebrae, often arising from ligamentous injury and jumped facets, increasing SCI risk. Facet dislocation occurs when the articular surfaces totally lose contact, while subluxation involves reduced contact between these surfaces. Osteoligamentous damage resulting from bilateral facet dislocations often incurs a higher risk of neurological injury. Allen et al coined the term "distractive flexion injuries" for facet subluxation and dislocation in 1982. The cervical spine comprises 7 vertebrae, each with distinct characteristics and functions. The 1st cervical vertebra, also known as the atlas or C1, lacks a vertebral body but features anterior and posterior arches with lateral masses. C1 articulates with the skull's occipital condyles, facilitating head flexion and extension. The 2nd cervical vertebra, also known as the axis or C2, is distinguished by a prominent dens (odontoid process) projecting superiorly from the body. The dens articulates and forms a pivot joint with the atlas, enabling rotational head movement. Vertebrae C3 to C7 possess more typical vertebral bodies with spinous and transverse processes. These vertebrae provide support, stability, and flexibility to the cervical spine, allowing for various neck movements. Intervertebral disks lie between each cervical vertebral pair, consisting of a fibrous external layer (annulus fibrosus) and a gel-like inner core (nucleus pulposus). These disks provide spine cushioning, shock absorption, and flexibility. The cervical spine has been subdivided anatomically and functionally into the following: The region from the occiput (C0) joint to C2, which is mostly responsible for rotational head movements. The subaxial cervical spine region (C3-C7), which predominantly shows flexion and extension movements. The spinal cord extends from the brainstem downward, encased within the protective spinal canal formed by the vertebral bodies. The spinal cord transmits sensory and motor signals between the brain and body. The cervical spinal nerves, comprising 8 pairs labeled C1 to C8, emerge from the spinal cord's cervical region and are crucial in upper body sensory and motor functions. Each nerve exits the spinal cord through the intervertebral foramina between adjacent cervical vertebrae. Sensory fibers transmit touch, pressure, position, temperature, and pain information from the skin, muscles, joints, and other upper body regions back to the spinal cord and brain. Conversely, the motor fibers relay brain and spinal cord signals to the upper body's skeletal muscles. Specific cervical spinal nerves have distinct roles based on their origin and distribution. For instance, the C1 nerve, known as the suboccipital nerve, innervates the suboccipital muscles at the skull base, contributing to head movement and posture. Additionally, C2 to C4 nerves contribute to the cervical plexus, giving rise to important nerves like the greater occipital (C2) and phrenic nerve (C3-C5). Spinal nerves C5 to T1 are crucial brachial plexus components that innervate upper body muscles and provide upper limb sensory function. Vertebral arteries travel through the C1 to C6 transverse foramina and supply blood to the brain, particularly the posterior circulation, and are vulnerable to injury in cervical trauma. Various ligaments stabilize the cervical spine, including the anterior longitudinal (ALL), posterior longitudinal, interspinous, and supraspinous ligaments, ligamentum flavum, and transverse ligament of the atlas. The main cervical spine stabilizers are the tectorial, cruciate, apical, and alar ligaments. The posterior ligamentous complex, disks, and apophyseal joints prevent anteroposterior translation exceeding 3 mm. Facet joints—synovial joints between adjacent vertebrae's articular processes—facilitate smooth movement and stability of the spine. However, these joints are susceptible to damage following an SCI.