Adult Cervical Spine Fractures

Introduction Anatomy Causes Types Symptoms Evaluation Treatment Rehabilitation Complications Summary

Introduction

There are probably no more scary words to describe an injury than "broken neck". For hundreds of years it was almost the same as "sudden death". Even today when you, or someone close to you, has "broken their neck" this event is bound to send anxiety to a new high. Fractures of the neck are actually quite variable. Some injuries are a great threat to life and independence; others are much simpler with excellent prospects for full recovery. Today, if you are alive after a neck fracture you are quite unlikely to die suddenly as long as you cooperate with the treatment. But, partial or complete paralysis after a neck injury is still a serious problem and may be permanent.

This guide will help you understand

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what parts of the neck are involved what the symptoms are what can cause these fractures how doctors diagnose these fractures what the treatment options are

AnatomyWhat structures are most commonly injured?

The neck is the flexible connection between the head and the body. The head is controlled by muscles that start from the neck or shoulder girdle and attach to the skull. The cervical spine is made up of seven bones called vertebrae. Between each vertebra are two joints. These joints allow a little movement between each vertebra forwards and backwards called flexion and extension, side to side movement, and rotation. Because there are seven segments, the small movement between each bone is multiplied. The neck as a whole can flex forward 45 degrees until the chin almost touches the chest and backward 50 degrees, until the chin is level with the ears.

Normally, you can bend your neck from side to side about 40 degrees. This means that you can put your ear halfway to the shoulder. Most people can rotate their head about 70 degrees, placing the chin on the shoulder. Injuries to the neck occur most often when the neck is forced beyond its normal range of movement - over rotation for example. The momentum of the head is important in the mechanism of injury. Neck injuries very often result from sudden changes in acceleration as in falls, motor vehicle accidents (particularly motorcycles), sports injuries, or diving into shallow water. The head wants to go one way and the body another. The neck in between becomes strained and is damaged.

The anatomical structure of the neck helps to explain how injuries occur. Each vertebra has a drum-like vertebral body in front. This is where the weight is transferred. The vertebral body

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can be injured when the compression forces on the neck are excessive. This may occur with little force when the bone itself is weakened by aging processes like osteoporosis.

Between one vertebral body and the next are ligaments. The ligaments prevent excessive movement. The intervertebral disc is a special type of ligament that sits between each vertebra. The disc provides some shock absorption and allows some rocking front to back and side to side movement. Too much compression may rupture the disc. Too much rocking can tear off the ligaments and cause instability between vertebrae.

Behind the vertebral body is an arch of bone called the lamina which protects the spinal cord, an extension of the brain that passes down to the level of the waist. At the back of the arch the spinous process projects backward. You can feel the tips of the spinous processes by pressing on the back of the neck. The lateral masses and the transverse processes project outwards from the arch. All these processes act as points of attachment for muscles of the neck. The lateral masses also act as support for joints with the next vertebra. Pull-off, or avulsion injuries occur where the muscles and ligaments attach to the spinous process, the transverse processes, and even sometimes the vertebral bodies.

The vertebrae stack on one another with facet joints between the lateral masses. The joints allow some movement of the neck. Too much movement can dislocate the joints, tear the ligaments and fracture the lateral masses and the laminae. These injuries are dangerous because the spinal cord and the spinal nerves are so close.

Spinal Cord Injury

With certain patterns of neck injury, damage to the spinal cord can cause quadriplegia (also called tetraplegia). Spinal cord injury affects the legs as well as the arms and usually both sides of the body are involved. This condition results in partial or complete paralysis below the neck. There may be no sensation or movement of the arms and legs (complete quadriplegia) or there

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may be movement and sensation in some areas left unchanged (incomplete quadriplegia). Both complete and incomplete quadriplegia may partly recover if the pressure from the bone fragments is relieved before the spinal cord tissue dies. Spinal cord tissue does not re-grow so any recovery may be partial. A great deal of attention in the management of neck fractures is paid to preventing spinal cord injuries from occurring or getting worse.

Spinal Nerve Injury

The nerves that leave the spinal cord in the neck pass into the arm and supply sensation and the control of movement in the arm and hand. The spinal nerves as they leave the spine are sometimes referred to as the "nerve roots". These spinal nerves travel very close to the bone of the vertebrae and to the intervertebral disc. As a result, they may be damaged or compressed by injury to these structures. Injury to the spinal nerves causes loss of sensation or weakness, often on one side only. The pattern of nerve function loss gives a clue as to which nerve root is injured.

CausesHow do fractures of the cervical spine commonly happen?

The complexity of the bone shapes and the various different ways that the neck may be stressed means that there are a large number of fracture patterns. These patterns are recognized and classified by the doctors to help with the treatment plan. This level of detail is not needed here but the fractures will be grouped according to mechanism of injury.

One important concept to understand about spine fractures is the stability of the injury. A stable fracture is one in which the broken pieces are not likely to move further out of position. The deformity seen on the initial X-rays will likely remain after healing. The critical aspect of

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stability is that damage or further damage to nerves or the spinal cord is unlikely in a stable fracture.

An unstable fracture is more dangerous. An unstable fracture carries the risk that the bone fragments may shift further out of position. The alignment of an unstable fracture may actually get worse over time. This can cause spinal cord or spinal nerve injury.

TypesBurst Fractures

Flexion Fractures

Atlantoaxial, Anterior Wedge fracture, Burst :

Teardrop Fracture, Odontoid, Spinous Process Fracture, Facet Dislocation:

Subluxation Injury

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SymptomsWhat symptoms do cervical spine fractures cause?

Many people with a broken neck have sustained multiple injuries. They may be unconscious or unable to cooperate and describe their symptoms. If there is any suspicion of a neck injury it is common practice to x-ray the neck to "clear" the cervical spine before moving or examining a patient. Emergency health care workers are very careful to protect the neck until the stability of the cervical spine is confirmed.

The most common symptom of a broken neck is pain. It may be localized to the neck or experienced in the shoulders or arms if the nerves are injured. The pain may be increased by moving the neck. Absence of pain does not rule out serious injury. The neck region is likely to be tender but the injured parts are so deep that feeling the broken parts is not possible and deep pressure not advisable.

Paralysis, loss of voluntary motor power, or numbness in the arms, trunk, or legs is an indication of spinal cord injury. One-sided neurological loss may be an indication of nerve root injury. The patterns and combinations of nerve and spinal cord injuries may be quite complicated. Some patients complain of a feeling of instability and even hold their head to "prevent it falling off" to alleviate this sensation. This is a very good indication of an unstable neck injury.

EvaluationHow will my fracture be evaluated?

Different types of fracture patterns relate both to the mechanism of injury and to the stability of the injury and therefore the prognosis. Evaluation of a neck injury begins with getting an account of the accident that caused it and reconstructing the forces that acted on the neck. This information may help to understand what type of injury to the cervical spine may have occurred.

A series of x-rays are taken. It is now common to do a CT scan of the spine if there has been a fracture or if there is a high index of suspicion for fracture. THE CT scan is more sensitive and

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may show fractures no seen on plain x-rays. If there is neurological injury or suspicion of intervertebral disc injury then an MRI is often done.

A careful physical examination is done to find any neurological problems. This helps to establish the completeness and level of the Spinal Cord Injury (SCI) if there is one. If the exam does not correlate well with the x-rays then further x-rays may be needed to rule out spine injuries at more than one level. If the patient has sustained multiple injuries, these must be evaluated and treated as well.

reatmentWhat treatments should I consider?

The goal of treatment for a fractured neck is to protect the spinal cord and nerves. The broken bones themselves heal well. Once they do, the injury becomes much more stable and less dangerous. Treatment is aimed at keeping the bones in good position, preventing instability and holding everything still until bone healing occurs. The spectrum of treatment runs from symptom relief and a soft collar - to surgery to reduce the fractures and stabilize the neck with wires, plates and screws.

Nonsurgical Treatment

Soft Collar

Stable fractures, such as the simple anterior compression fractures and spinous process fractures may only require symptomatic support. The soft collar is commonly used. The soft collars are made of foam rubber. They fit snugly round the neck and improve comfort, but they do not support the head or protect the neck from further injury.

Hard Collar

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For more significant, but stable fractures, a hard collar may be a better choice. It is not possible to completely immobilize the neck with a hard collar, but you can limit flexion, extension and rotation. Stable patterns of C1 and C2 fractures (Type I Odontoid, C2 Pedicle fracture, Extension Teardrop Fracture) can often be treated in this fashion. These devices are made of rigid materials and are adjustable to fit against the back of the head and under the chin. They essentially prevent major movements of the neck. They may also be used after surgery.

Traction

Traction is commonly used immediately after a spinal fracture to stabilize the cervical spine. Traction is applied by placing special tongs into the skull under local anesthetic. The tongs are made of two parts: a C-shaped metal brace that will be placed over the skull, and two metal pins threaded through the ends of the tongs. The metal pins are inserted through the skin and into the bone of the skull, one on either side of the head just above the ear. The tongs grip the skull so that traction can be applied pulling the head away from the body.

A cord is placed from the tongs to a pulley at the head of the bed and weights applied. Traction is usually a temporary measure to assist with reduction of fractures or dislocation of the neck, or to keep the neck stable while assessment is made or a treatment plan. Traction is often followed by immobilization in a halo thoracic brace or by definitive surgery to maintain position while the bones heal.

Halo-thoracic Brace

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A Halo is used when an unstable fracture requires immobilization of the cervical spine. The "halo" gets its name from the metal ring which is fixed to the skull with screw pins. It is attached by metal bars to a vest which goes around the chest (thorax). This arrangement means that the weight of the head is not transferred to the neck but is diverted through the brace. The brace also reduces movement of the neck. The upper end of the neck is held more stationary than the lower end where there is movement between the vest and the chest. This option is used for more unstable patterns of upper cervical injury and post operation to protect the area while the bone heals.

Surgery

Surgery is avoided where possible. Surgery is undertaken without hesitation in an unstable fracture with risk of causing or worsening SCI.

Surgery is required for many unstable cervical spine fractures. If an unstable fracture shifts position in a brace or traction, or if the patient's neurological condition gets worse, then surgery is undertaken to restore stability. Some fracture patterns are so unstable that deterioration is very likely. Surgery may be recommended as a preventive measure to prevent spinal cord damage. The surgeon analyzes the fracture pattern to determine whether the most serious disruption is in front or behind. If the main problem is in front the neck is exposed from the front and stability restored by fixing the bones with screws, wires, or metal plates. When the damage is at the back, then surgery is undertaken through the back of the neck.

Fusion means joining one vertebra to another and allowing the two (or more) vertebrae grow together, or fuse, into one bone. When the vertebrae are fused, the motion between the two vertebrae is eliminated permanently and stability is restored. This type of operation may be undertaken for burst fractures and some unstable odontoid fractures. The metal implants inserted to hold the bone usually remain in place forever. It is unusual for wires, screws, or plates to cause any symptoms in this region.

RehabilitationWhat happens as I recover?

Healing of the bony injury takes approximately three months to achieve 80% of eventual strength, enough to return to light normal activities. Bracing is usually continued for this length of time. After that there are slow improvements that may continue for up to 18 months.

The healing of the soft tissue components of a neck injury are even more important than they are in other injuries. If the muscles and ligaments are torn, the mechanics of the cervical spine may never fully recover. If there is a nerve injury or spinal cord injury the recovery is often incomplete. A nerve or spinal cord injury affects recovery far more than the bone injury.

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The spectrum of outcomes after a neck fracture goes from complete recovery and full return to normal function in three to six months to permanent paralysis and a wheelchair existence. It is usually possible to determine, quite early, which of these outcomes will occur. Both of these extremes require physical therapy but, of course, of very different types. Those destined for full recovery need to undertake an early exercise program that will safely maintain the function of the unaffected limbs and then exercise the neck and upper extremities to recover strength, range, and endurance. By contrast, those with a spinal cord injury need early rehabilitation focusing on strengthening the remaining function of the arms and learning mobility in a wheelchair. Maintaining independence despite paralysis is the goal of rehabilitation.

Apart from the permanent nerve injuries, the main long-term concern from neck fractures is post traumatic arthritis. If the joints of the neck are injured or if the disc is disrupted, neck mechanics will not be normal. Over time, this may result in pain and stiffness of the neck. Arthritis in the neck may cause formation of bone spurs around the joints. In time, these may interfere with nerve or spinal cord function. Fusion at the time of the acute injury is intended to prevent this type of outcome.

ComplicationsWhat are the potential complications of this fracture?

Because neck fractures often occur in the setting of multiple trauma the complications of other injuries, head trauma, shock, chest and abdominal injuries or long bone fractures may take precedence. Spinal shock in the context of SCI is also a concern. However, assuming that these elements are cared for by the trauma team there are still complications specific to the injury.

Malunion

Malunion occurs when a fracture heals in a bad position. This can occur if reduction is unsuccessful or efforts to hold an unstable fracture fail. In the cervical spine, bad position usally means that the nerves or spinal cord is vulnerable to further injury. This situation is rare. Usually, when the bone heals the stability of the neck is improved even if the new shape is not normal. If malunion occurs where the angulation or displacement is so severe that nerve or cord injury becomes likely, surgery is required to decompress the neurological elements and fuse the spine.

Nonunion

Complete failure to heal (nonunion) is very rare in nonsurgical cases. After most types of fusion operations in the neck healing rates are between 90 & 95% leaving 5 - 10% with nonunion of

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the fusion (not usually the fracture). If the result is stable and not too painful you may elect to leave this alone. However, the situation can result in breakage of the metal pins and screws by fatigue failure. This is a rare and difficult situation which usually requires repeat surgery to achieve painless healing of the fusion.

Infection

Infection of an operative site occurs with a frequency of between 1/200 and 1/50. Treatment of this situation will always include antibiotics. Ideally, one would like to remove all the metal pieces to help clear up the infection then re-operate to make the situation stable and painless. This may not always to possible and the treatment depends on the individual case.

Progressive Neurological Deterioration

Deterioration of the neurological injury during the course of recovery of the bony injury is a feared complication. Any extension of a cord injury at this level has very serious consequences with further disabilities and a greater risk of mortality. Surgery to attempt to stabilize the spine and prevent this complication may itself damage the spinal cord or its blood supply. The balance is in favor of surgery helping the situation but not always.

Depression

Depression is common and understandable when faced with the change from an active life to one of dependency. It is a fact that spinal cord injured patients lead a full and fulfilling life but the process of coming to terms with the new situation can be very stressful.

Degerative Arthritis

As discussed earlier, the long-term risk of posttraumatic arthritis of the neck is significant. Any

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