A C1 spinal cord injury (SCI) refers to damage at the uppermost region of the spinal cord. As a result, C1 SCIs can affect motor control and sensation throughout the entire body.
This article will go over everything you need to know about C1 SCIs including:
- The Anatomy of the Spinal Column
- Functions Affected by C1 Spinal Cord Injury
- Potential Complications of C1 SCI
- C1 SCI Rehabilitation
Anatomy of the Spinal Column
The cervical region of the spinal cord is encased within the 7 cervical vertebrae at the top of the spinal column. The nerve roots at each level of the spinal cord exit above their corresponding vertebrae. Therefore, the order is C1 nerve, C1 vertebra, C2 nerve, C2 vertebra, and so on.
The C1 and C2 vertebrae are different from other vertebrae in terms of shape and function. Despite being the smallest vertebrae in the cervical region, they are responsible for the range of motion of the head.
The C1 vertebra (the atlas) is the uppermost vertebra. It connects to the base of the skull and forms the atlanto-occipital joint. This joint allows you to nod your head up and down.
The atlas is shaped like a ring and connects to the C2 vertebra (the axis) and forms the atlanto-axial joint, which is what allows you to shake your head from left to right.
Because the C1 and C2 vertebrae are so closely aligned, C1 and C2 injuries typically occur together.
The atlas and axis are crucial because they stabilize the skull, enable neck movement, and protect the spinal cord.
Up next, we’ll discuss what functions can be affected after a C1 spinal cord injury.
Functions Affected by C1 Spinal Cord Injury
Because C1 is the uppermost segment of the spinal cord, motor control and sensation throughout the entire body can be affected.
This occurs because messages between the brain and areas below the level of injury are unable to get past the damage to the spinal cord.
When determining level of injury, physicians will test your sensory and motor functions in accordance with the International Standards Examination. The C1 nerve root does not have a sensory test point. Instead, if sensation is affected at the C2 test point, the sensory level is classified as C1.
However, a C1 spinal cord injury does not always affect motor control and sensation throughout the entire body. This primarily depends on the severity of injury. One way to refer to the severity of a spinal cord injury is to determine its completeness. Often, a CT scan or MRI is used to determine whether the injury is complete or incomplete.
A complete SCI refers to a spinal cord lesion that completely transects the spinal cord, cutting off all connections between the brain and areas innervated below the level of injury. In contrast, an incomplete SCI refers to partial damage at the level of injury and results in spared neural pathways.
Spared neural pathways indicate that some connections between the brain and areas below the level of injury exist. As a result, even after a C1 spinal cord injury, some individuals may have sensation or motor control below their level of injury.
Generally, the milder the spinal cord injury, the more spared neural pathways exist, and the greater the recovery outlook.
In the following section, we’ll discuss potential complications that can arise after a C1 SCI.
Potential Complications of C1 Spinal Cord Injury
Because a C1 spinal cord injury can affect motor control and sensation throughout the entire body, it’s a good idea to understand potential complications that can arise and be prepared to manage them.
1. Breathing Difficulties
Without immediate medical attention, C1 spinal cord injuries are typically fatal. The C3-C5 spinal nerves innervate the diaphragm, and because messages from the brain may not be able to get past the C1 level, individuals may not be able to breathe.
The main priority when treating someone with a C1 SCI is to stabilize their breathing. Individuals generally require ventilator assistance to restore breathing.
Due to breathing difficulties, individuals may also experience difficulties communicating.
2. Caregiver Dependence
Those with complete paralysis throughout their bodies after a C1 SCI need the full-time assistance of a caregiver to perform activities of daily living like bathing, grooming, feeding, and toileting.
3. Changes in Body Composition
Because spinal cord injuries at the C1 level can significantly affect most body movements, individuals often experience physical changes to the body as a result of limited active movement.
Consequences of reduced physical activity include:
- Reduced bone density
- Muscle atrophy
- Poor circulation
- Lowered resting metabolic rate
4. Bladder and Bowel Dysfunction
If messages from the bowel and bladder cannot pass through the damage in the spinal cord to reach the brain, then individuals with C1 SCIs may experience changes to their bowel and bladder functions. As a result, they will not be able to sense when their bladder or bowels are full and are susceptible to leaking and accidents.
To prevent bowel and bladder-related accidents from occurring, individuals with C1 SCIs need to follow a bowel and bladder program.
5. Pressure Sores
If individuals lose sensation after a C1 SCI, they likely won’t feel antsy when sitting or lying in the same position for prolonged periods. However, failure to frequently change positions places too much pressure on certain parts of the skin, which can cut off blood flow and cause the skin to break down. Areas of skin breakdown due to prolonged periods of sitting or lying down are known as pressure sores.
To prevent pressure sores from developing, change positions every two hours when lying in bed or every 30 minutes when sitting in your wheelchair.
6. Autonomic Dysreflexia
Autonomic dysreflexia is characterized by a spike in blood pressure due to stimulation below the level of injury. The most common causes of autonomic dysreflexia are a full bladder, distended bowels/constipation, tight clothes, skin irritations, and extreme temperatures.
Other symptoms of autonomic dysreflexia include headache, hypertension, sweating, and shortness of breath.
Spasticity describes involuntary muscle contractions. The muscles remain contracted because they’re not receiving signals from the brain to relax. Individuals with spasticity may experience stiff or jerky movements.
While spasticity can be uncomfortable and cause pain, it is not always a bad thing. In fact, a little bit of spasticity can prove beneficial and help maintain muscle mass and promote circulation.
Now that you understand the potential complications of a C1 spinal cord injury, let’s discuss rehabilitation.
C1 Spinal Cord Injury Rehabilitation
Depending on the severity of your C1 spinal cord injury, rehabilitation goals will vary.
Those with milder injuries should be able to participate in various rehabilitative therapies to improve their functional abilities and mental health. Rehabilitative therapies can include:
- Physical therapy focuses on maximizing mobility through targeted exercise. If functions below your level of injury are spared, PT may be able to help you strengthen those movement patterns.
- Occupational therapy teaches you new ways to perform activities of daily living like grooming, dressing, and toileting to help you become as functional as possible. This can involve learning how to use adaptive tools.
- Speech therapy can help you address respiratory and communication difficulties.
- Psychotherapy can help you cope with the emotional and psychological outcomes of SCI. A psychotherapist can provide helpful insight and resources to help you cope.
Those with more severe C1 SCIs must learn how to work and communicate with their caregivers to perform everyday tasks.
C1 Spinal Cord Injury: Key Points
A C1 spinal cord injury can affect functions throughout the entire body. However, depending on the severity of injury, motor impairments and loss of sensation will vary.
C1 SCIs are extremely dangerous and often fatal because they can affect one’s ability to breathe. Therefore, it’s essential to seek immediate medical attention.
Life after a C1 spinal cord injury often requires significant lifestyle changes. With the support of your caregivers, rehabilitation specialists, and loved ones, learning to cope and adapt is possible.
Featured image: iStock/magicmine