Epidemiology

In 1970 the first federally funded Model Spinal Cord Injury Care Systems (MSCICS) were developed. Currently there are 14 such centers (there were 18 before funding was cut) as designated by the National Institute on Disability and Rehabilitation Research (NIDDR). Each center represents a comprehensive interdisciplinary service delivery integrating all aspects of care for the SCI patient from the initial injury to lifelong follow-up. The model centers are based on the principles set forth by Sir Ludwig Guttman, a British physician who pioneered advances in the care of SCI patients during World War II¹:

The 14 MSCICS centers and 8 previously designated centers have been contributing clinical information to a national database following a jointly agreed-upon protocol. They have been able to report results on the basis of an estimated 13% of all SCI injuries in the United States occurring since 1973. The database contains information on about 25,000 spinal cord injured persons.³ The end result is a wealth of information regarding injury trends from 1973 to1998 and some recent updates that include information through the year 2004. The data not only allow physicians to know the current status of SCI patients but also give physicians the ability to spot trends in the demographic data. These changes in the demographics of SCI have allowed rehabilitation programs and centers to “change with the times” to reduce the cost and ultimately improve the quality of medical rehabilitative care for their patients with SCI.⁴

Mortality

Many years ago, the leading cause of death among persons with SCI was renal failure. Pulmonary embolus (PE) usually in the first few weeks after injury, and most often associated with a deep vein thrombosis (DVT), was another frequent cause of death. Advances in urologic management, DVT and PE prevention, and early mobilization have reduced the number of early deaths. Today, renal failure rarely occurs in the acute SCI setting. Because more SCI patients live not only through their first year after injury but also survive to old age, cardiovascular disease has become a more frequent cause of death (Fig. 84–1). Nash and colleagues⁷ demonstrated that SCI is an independent risk factor for developing multiple risks for cardiovascular disease such as increased cholesterol. Respiratory illness, particularly pneumonia, is now the leading cause of death among older SCI patients with cervical injuries.⁸ The cause of death in persons with paraplegia is more varied. In addition to heart disease, cancer, suicide, and septicemia are the leading causes.

FIGURE 84–1 Cause of death after spinal cord injury.

Etiology

The causes of spinal cord injury are typically divided into traumatic and nontraumatic. The top five causes of traumatic SCI in males are auto accidents, falls, gunshot wounds, diving, and motorcycle accidents.³ The top three remain the same in women, but the final two are medical causes and diving³ (Fig. 84–2).

FIGURE 84–2 Etiology of spinal cord injury by gender of patients.

(Adapted with permission from Jackson AB, Dijkers M, DeVivo MJ, Poczatek RB: A demographic profile of new traumatic spinal cord injuries: Change and stability over 30 years. Arch Phys Med Rehab 85:1740-1748, 2004.)

The major trend is that violent injuries have decreased from 20% in the 1990s to 9.8% in 2000s.³ Geographic variations occur depending on the state or city. In the older SCI patients, in addition to falls, nontraumatic causes of SCI such as cancer, vascular injuries, and infection make up a larger proportion of injuries.

Etiology is also reported in terms of major groups. Figure 84–3 illustrates the frequency that each of these groups causes SCI.

FIGURE 84–3 Etiology of spinal cord injury.

(Adapted with permission from Jackson AB, Dijkers M, DeVivo MJ, Poczatek RB: A demographic profile of new traumatic spinal cord injuries: Change and stability over 30 years. Arch Phys Med Rehab 85:1740-1748, 2004.)

Classification of Spinal Cord Injury

The spinal cord has three basic physiologic functions. The ascending tracts in the cord receive sensory information from the somatic and visceral receptors through dorsal root ganglia and transmit this information to higher centers. The descending tracts receive signals from higher centers and ultimately transmit these signals to target sites via the ventral roots. The other basic function of the spinal cord is to modulate these signals via a variety of local mechanisms.

Assessment, treatment, and classification of spinal cord injury flow directly from the anatomy, physiology, and topography of the spinal cord. Classification or grouping of patients allows the rehabilitation physician to predict the outcome and ultimate function in a majority of patients on the basis of others with similar injuries. This allows the rehabilitation team to design a rehabilitation program appropriate for individual SCI patients to give them the best opportunity to maximize their potential functional outcome.

The most accurate way to assess a patient who has suffered an SCI is to perform a standardized physical examination as outlined by the American Spinal Injury Association. The neurologic examination includes two key components—the motor and sensory examination with required and optional elements. The result allows the clinician to compile a score and determination of the completeness of injury. The neurologic level is also determined by rules set forth in the ASIA examination. From these data a functional classification is assigned to each patient. This information can then be used to design each patient’s rehabilitation program and predict his or her functional outcome on the basis of previous patients with similar injury classifications.

Two assessment tools are used in the evaluation of patients after SCI.⁹ One is the neurologic classification of SCI using the ASIA impairment scale. The other is the functional score, or Functional Independence Measure (FIM) score.

The ASIA impairment scale measures the degree of completeness of injury using categories from A to E (Table 84–1). Complete paralysis is defined as the absence of sensory and motor function in the lowest sacral segments and incomplete paralysis as preservation of sensation below the level of the injury including the lowest sacral segments. Sacral sparing is defined as voluntary anal contraction or presence of dull touch and pinprick sensation in the rectal and perianal area.

TABLE 84–1 American Spinal Injury Association (ASIA) Impairment Scale

In addition to the ASIA impairment scale is a scoring system that measures the strength of each muscle on a 6-point scale (0 to 5) and sensation for pinprick and dull touch on a 3-point scale (0 to 2). The motor level of SCI is defined as the lowest normal motor segment that has a grade 3 or more, providing the muscles above that level are graded as a 5. The motor level best reflects the severity of impairment and disability during rehabilitation.

FIM score is a widely accepted functional assessment tool and is currently used as an indicator of function in patients with SCI. FIM is an 18-item scale. There are two categories of items, motor and cognitive. Individual items in each category score from 1 to 7, from “total assistance” to “complete independence.” There are 13 items of motor scoring important in determination of self-care, sphincter control, and mobility (Box 84–1). Scores falling below 6 indicate that the patient requires another person for assistance. Many rehabilitation units now use FIM scores to measure patient outcomes. Quality assurance units use these data from groups of patients to draw inferences on the effectiveness of the rehabilitation unit.

Clinical Syndromes

In addition to classifying patients on the basis of their individual motor and sensory injury levels, the following specific clinical syndromes have been identified in the literature: central cord, anterior cord, posterior cord, Brown-Séquard, conus medullaris, and cauda equina syndromes.^10,11

Therapy Approaches

As stated earlier, rehabilitation of the SCI patient begins from the moment of injury. Quick response, transfer to a level I trauma center, and prompt medical and surgical treatment results in a minimizing of medical complications and preservation of neurologic function. In the acute hospital setting, important recommendations given on consultation with the SCI specialist include treatment of neurogenic bowel and bladder, prophylaxis of DVT and PE, prophylaxis of gastric ulcer, preventing atelectasis and pneumonia via proper pulmonary management, and preventing skin ulcers with proper positioning in bed and turning every 2 hours. Physical and occupational therapies are initiated in the acute hospital unit once the spine is stabilized. Range of motion (ROM) is performed to the shoulders, hips, elbows, and heel cords. ROM should be performed twice daily to prevent joint contractures and can be taught to family members. Splints are made for the upper extremities for the same reason. The patient begins to build tolerance to sitting and is taught weight shifting to prevent pressure ulcers. The goal is to achieve medical stability so that the injured patient can be admitted as quickly as possible to a multidisciplinary inpatient rehabilitation hospital that specializes in SCI treatment.

Once the acute treatment is completed and the patient is deemed “medically stable,” the rehabilitation course is assisted with the quickest possible transfer to the rehabilitation unit. In cases of high tetraplegia, medical stability may be achieved while the patient is still on a ventilator. The result of a shorter length of stay in the acute hospital and quicker move to rehabilitation is to lower the cost to the “health care system” and improve the ability of patients to quickly see functional recovery.

Moving patients quickly through rehabilitation has some negative consequences, too. Sometimes patients do not have a chance to psychologically adjust to their injury fully. Additionally, shorter lengths of stay have also moved to the rehabilitation hospital.

Unfortunately, these shorter lengths of stay that are often forced on patients and rehabilitation providers by insurance company mandates continue a trend that patients will need to complete their physical, functional, and psychologic rehabilitation as outpatients. Therefore it is imperative then that the rehabilitation be focused and aggressive to accomplish as much as possible in a shorter amount of time. The challenge is to provide SCI patients with the highest quality rehabilitative care despite these imposed constraints so that they leave the hospital with the highest possible outcome.

On the rehabilitation unit, the SCI patient begins a new journey. The basic skills of mobility, self-care, and bladder/bowel functions are relearned regardless of the severity of the injury—sometimes quickly but other times painfully slowly. Patients try to achieve independence in each area, although sometimes only modified or partial independence is possible. The level of neurologic injury best predicts the level of independence and mobility each patient can achieve,¹⁵ even though individual differences occur. SCI patients use a significant time in rehabilitation to review a variety of handbooks and computer programs to become educated on their injury. Most patients also receive counseling for emotional and psychologic adjustment, discover initial vocational options for their future, and participate in recreational and leisure activities that ease their reintegration into society. A subset of SCI patients who suffered concurrent head trauma receives cognitive testing and retraining. Another subset of SCI patients who remain on ventilators receives breathing and communication training. Finally, each patient is discharged to the most independent living situation possible. Usually they can only go home after multiple modifications are built and after a myriad of adaptive equipment is prescribed.

Because the tasks of rehabilitation can be so daunting and involve so much of the “whole person” with all organ systems including the psychosocial system affected, only a dedicated multidisciplinary team can accomplish a successful comprehensive rehabilitation. Each member of the multiple rehabilitation disciplines functions together as a team to optimize each patient’s outcome.¹⁶ Historically the leader of the team has been the rehabilitation physician, or physiatrist, who would create the rehabilitation goals, lead weekly team meetings, and decide when the program is complete. More recently, most rehabilitation programs have shifted to a more patient-centered approach with the interdisciplinary team working toward goals set forth together.¹⁷ All disciplines focus their treatments on the patient, so teamwork and treatment overlap are encouraged. With this approach the patient, and often his or her family, is intimately involved in deciding the direction of the rehabilitation and the date of discharge. The individual disciplines are listed in Table 84–2.¹⁸

TABLE 84–2 Interdisciplinary Team