In this paper 1, the authors provide an overview of the causes, symptoms and treatments of cervical degenerative disc disease (DDD).
Overview of the intervertebral disc (IVD)
An intervertebral disc (IVD) acts as a shock absorber between each vertebra in the spinal column and is critical for spinal mobility and stabilization. It comprises two parts: the annulus fibrosus (AF) and the nucleus pulpous (NP). The AF is made up of type 1 collagen in layers and forms a strong shell for the NP. The NP has a gel-like consistency composed mainly of water but also contains type II collagen and proteoglycans.
Cervical Degenerative Disc Disease: who, what, why?
Cervical disc degeneration is a normal part of ageing, starting in the late teens and continuing through life. The prevalence of cervical DDD increases with age regardless of whether a patient has symptoms. Some environmental and genetic factors can predispose individuals to the development of this disease, including handheld electronics, contact sports and prior surgeries.
Typically, changes occur within the NP first, followed by progressive degeneration of the annulus. With ageing, the disc loses water, becoming less compliant. This leads to a decrease in disc height and collapse. These changes can increase the force exerted on the degenerated NP, which is then transmitted to the AF, causing it to tear and fracture. This may lead to a herniation where the NP is pushed out of the AF.
The spine segments become hypermobile leading to instability, stiffness and a decrease in motion of the spine. While not all patients with cervical DDD experience pain, it is one of the most common findings.
Making a patient history is important to ensure that the symptoms (if they are present) result from degeneration and not other conditions that have similar symptoms, such as carpal tunnel syndrome or rheumatologic disorders. Additionally, a comprehensive neurological assessment must be done, testing upper and lower extremities, gait, balance, reflexes and range of motion.
Most commonly, patients will present with axial neck pain and difficulty moving. Some may have headaches, shoulder pain or pain on one side of the back, arms or legs that can worsen with movement. Other signs and symptoms may include changes to deep tendon reflexes, muscle atrophy or weakness.
Most often, the earliest and most significant degeneration occurs at C5-C6. However, different parts of the cervical spine have symptoms in different areas. For example, with a herniation at C7, patients will often complain of pain from the neck radiating to the forearm, palm, and middle finger. With the C6 nerve affected, patients may present with pain radiating to the neck, shoulder and down to the thumb and index finger.
As cervical DDD may be asymptomatic, degenerative changes might only be seen with CT, X-ray, or MRI imaging. Laboratory testing can help in diagnosis by ruling out infections, autoimmune arthritis or a metabolic disorder.
The focus of treatment for cervical DDD is to decrease pain, improve function and minimize symptoms. Generally, treatment begins with a nonoperative approach but can lead to surgery.
Nonoperative treatments range from rest, activity changes, physical therapy such as ROM and isometric activities, and medications including anti-inflammatories, muscle relaxants and steroids.
For patients that do not respond to non-operative approaches, surgery may be required. This is particularly the case for patients in pain, experiencing neurological symptoms or patients with cervical myelopathy. Several surgical options are depending on the case. One option is decompression surgery, which can take many forms. For example, these procedures may involve removing a disc (or discs), may include the fusion of different segments or may involve the insertion of a plate to increase stability and mobilization.
The pain and disability often associated with cervical DDD can significantly impact the quality of life for patients both personally and professionally. Therefore, a timely diagnosis and support from other health care professionals and patient education are key to minimizing negative outcomes.