1 Clinical Perspectives on Spinal Injuries

W. S. El Masry and A. E. Osman

Introduction

Traumatic spinal column injuries are potentially catastrophic events in an individual's life. When associated with neurological damage they result in devastating medical, psychological, social, emotional, financial, vocational, environmental, and economic consequences.

The impact of the effects of the neurological damage on the individual and those related to him/her can, however, be minimized. With good management of all aspects of paralysis from the time of the injury, many initially paralyzed patients can make significant neurological recovery and walk again. With ongoing expert monitoring, care, and support, those who do not recover are able to lead fulfilling and fruitful lives, as well as contribute to society.

A thorough assessment of the patient, including full neurological examination, appropriate radiological investigations, and accurate documentation of the findings, is of paramount importance in initiating good management and in monitoring progress.

As spinal cord injury (SCI) affects the physiology of almost all systems of the body, any assessment should encompass more than spinal column or spinal cord functions.

Fig. 1.1 Heterotrophic ossifications in a tetraplegic patient. They can be detected early with an ultrasound scan. Early treatment with biphosphonates and anti-inflammatory medication minimizes the severity of the outcome.

Effects of Spinal Cord Injury

A spinal cord injury results in a generalized physiological impairment that involves most systems of the body either directly or indirectly.

The physiological impairment and the consequent multi-system malfunction caused by SCI are dynamic in nature throughout the patient's life. The rate of change in the functioning of the various systems of the body is more rapid, though predictable, in the early stages (first 4-6 months) following injury.

Unpredictable changes in functions will inevitably occur throughout the patient's life, when the condition is likely to be perceived by most clinicians as being stable. The importance of frequent reassessments and repeated documentation at all stages following injury cannot be overemphasized. The only difference in the requirement for monitoring between the acute stage and the lifelong follow-up is the frequency of the monitoring.

In the absence of complete neurological sparing or full neurological recovery, the majority of patients with spinal cord injuries have sensory impairment or sensory loss below the level of their injury. Associated injuries and/or pathological complications can, therefore, develop in the absence of the conventional symptoms and signs, resulting in delay of diagnosis often with unpleasant consequences (Fig. 1.1).

When a complication develops, the interruption of the higher coordinating and moderating functions of the brain at the site of the spinal cord injury usually results in multiple and/or cascading intersystem effects, which are rarely seen in other conditions and which are seldom easy to manage. For example, an anal fissure, while painless, may nevertheless cause excess spasticity, which in turn may cause a fall and fracture of a long bone. Alternatively, excess spasticity involving the pelvic floor muscles may result in urinary retention, autonomic dysreflexia, and possibly a cerebrovascular accident.

The multi-system malfunction caused by the spinal cord injury is not only a source of multiple disabilities, but also a potential source of a wide variety and range of complications. What is perhaps not widely appreciated is that almost all complications following spinal cord injury are preventable.

Fortunately, the incidence of spinal cord injuries is the lowest of all major traumas. However, a combination of low incidence and high complexity necessitates an even more thorough and time-consuming systematic assessment than usual. The management of such patients, once they are stable for transfer, is therefore easier and safer to conduct in spinal injuries centers. These centers are usually equipped with the infrastructure of both the required expertise of adequately trained multidisciplinary teams and the necessary equipment. They are geared to provide comprehensive management, while giving equal attention to details that are necessary to ensure safety, comfort, and a good outcome for the patient, as well as medico-legal protection for the clinician and the institution.

Clinical and Radiological Assessment in the Acute Stage

Missed Spinal injuries

Missed spinal injuries are regularly reported in the literature.1–4 It is probable that in a significant number of patients the diagnosis of a spinal cord injury is delayed without being reported. Delaying diagnosis can result in increased neurological impairment.4,5 This is likely to result in more paresis or paralysis, increased disability, more disturbance of function of the various systems of the body and more complications. It is indeed a disaster to miss a spinal fracture or delay its diagnosis. It can easily be alleged that the neurological impairment has been caused or at best aggravated by failure to diagnose the fracture promptly. A delay in diagnosis is not unusually perceived by some patients and lawyers as having led to delays in ensuring appropriate precautions and adequate treatment. It is therefore paramount that no effort is spared in making as accurate a diagnosis in the accident and emergency department as possible. A high level of suspicion is a major prerequisite to early diagnosis in patients presenting following major trauma. The knowledge that a small group of patients with certain bone conditions, for example ankylosing spondylitis, osteoporosis, osteogenesis imperfecta, is more vulnerable to spinal injuries following minor trauma is at least equally important.

A thorough assessment of the patient including a full neurological examination together with appropriate radiological investigations, and accurate documentation of the findings are of paramount importance for initiating good management and monitoring progress.

Clinical Diagnosis of SCI in the Conscious Patient

A conscious alert patient, who is able to communicate and has symptoms of neck or back pain, rigidity, or tenderness in the spine following trauma is likely to have sustained a spinal column injury.6 There are, however, some rare exceptions. Pain may not be a feature in elderly patients with pure cervical ligamentous injuries without major vertebral damage in spondylotic spines. The author has personally witnessed this in a small number of patients, some of whom successfully pursued litigation. Extreme pain from other associated injuries may also mask pain from a spinal fracture with consequences to the timely diagnosis of a spinal injury.7 Neck pain, loss of consciousness following injury (regardless of duration), and/or neurological deficit are clinical predictors of unstable cervical spinal injuries requiring immediate radiological investigation of the cervical spine.8,9 The clinical diagnosis of a spinal cord injury in the conscious patient, who has no associated major injuries can be made without difficulty. Loss or impairment of motor power, sensation, and reflexes are indicative (individually or in combination) of damage to the spinal cord or the cauda equina depending on the level of impairment. Extra care should be taken in patients with L2 injuries and below. A traumatic injury below the level of S1 without injury to the cauda equina is rare. If present, it can, however, present with normal tendon reflexes and unimpaired motor power.

It is essential to determine at the earliest stage possible both the level and the density of the neural tissue damage.

The level of the injury is defined by the last normal dermatome and myotome. It is now internationally accepted by all experts in the field that the dermatomal and myotomal distributions may be abnormal for three segments below that level. In other words both sensation and motor power could be present but impaired in three segmental distributions below the last normal segment. For example if the last normal sensation is at the dermatomal distribution of C5 but there is hypoesthesia or analgesia in the dermatomal distribution of C6, C7, and C8 the level of the injury should be defined as C5. The impairment of sensation in the dermatomal distribution of C6, C7, and C8 can be explained by the logical assumption that the spinal cord segments C6, C7, and C8 are not completely damaged. Damage of these segments is incomplete; hence these segments represent the “zone of partial preservation.”

The density of the deficit from the damaged area in the spinal cord is defined by the presence or absence of sparing of sensation with or without sparing of motor power below the zone of partial preservation.

Absence of motor power including voluntary contraction of the anal sphincter and loss of sensation including loss of anal sensation below the zone of partial preservation are usually indicative of a clinically complete cord injury at the time of the examination. It is important, however, to appreciate that not all clinically complete injuries in the early hours or days following SCI remain clinically complete.10,11 Spinal shock can also mimic an initially complete injury following which significant recovery can occur.

The presence of sensation, however patchy or impaired, below the level of the zone of partial preservation is indicative of some anatomical sparing of sensory tracts and possibly also of corticospinal...