Chapter 024. Gait and Balance Disorders (Part 5)

FallsFalls are a common event, particularly among the elderly. Modest changes in balance function have been described in fit older subjects as a result of normal aging. Subtle deficits in sensory systems, attention, and motor reaction time contribute to the risk, and environmental hazards abound.Epidemiologic studies have identified a number of risk factors for falls, summarized in Table 24-3. A fall is not a neurologic problem, nor reason for referral to a specialist, but there are circumstances in which neurologic evaluation is appropriate. In a classic study, 90% of fall events occurred among 10% of individuals, a group known...
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Chapter 024. Gait and Balance Disorders (Part 5) Chapter 024. Gait and Balance Disorders (Part 5) Falls Falls are a common event, particularly among the elderly. Modest changesin balance function have been described in fit older subjects as a result of normalaging. Subtle deficits in sensory systems, attention, and motor reaction timecontribute to the risk, and environmental hazards abound. Epidemiologic studies have identified a number of risk factors for falls,summarized in Table 24-3. A fall is not a neurologic problem, nor reason forreferral to a specialist, but there are circumstances in which neurologic evaluationis appropriate. In a classic study, 90% of fall events occurred among 10% ofindividuals, a group known as recurrent fallers. Some of these are frail older persons with chronic diseases. Recurrent fallssometimes indicate the presence of serious balance impairment. Syncope, seizure,or falls related to loss of consciousness require appropriate evaluation andtreatment (Chaps. 21 and 363). Table 24-3 Risk Factors for Falls, a Meta-Analysis: Summary ofSixteen Controlled Studies Risk Factor Mean RR (OR) Range Weakness 4.9 1.9–10.3 Balance deficit 3.2 1.6–5.4 Gait disorder 3.0 1.7–4.8 Visual deficit 2.8 1.1–7.4 Mobility limitation 2.5 1.0–5.3 Cognitive impairment 2.4 2.0–4.7 Impaired functional status 2.0 1.0–3.1 Postural hypotension 1.9 1.0–3.4 Note: RR, relative risks from prospective studies; OR, odds ratios fromretrospective studies. Source: Reprinted from Masdeu et al, with permission.The descriptiveclassification of falls is as difficult as the classification of gait disorders, for manyof the same reasons. Postural control systems are widely distributed, and a numberof disease-related abnormalities occur. Unlike gait problems that are apparent onobservation, falls are rarely observed in the office. The patient and family mayhave limited information about what triggered the fall. Injuries can complicate thephysical examination. While there is no standard nosology of falls, commonpatterns can be identified. Slipping, Tripping, and Mechanical Falls Slipping on icy pavement, tripping on obstacles, and falls related to obviousenvironmental factors are often termed mechanical falls. They occasionally occurin healthy individuals with good balance compensation. Frequent tripping fallsraise suspicion about an underlying neurologic deficit. Patients with spasticity, legweakness, or foot drop experience tripping falls. Weakness and Frailty Patients who lack strength in antigravity muscles have difficulty rising froma chair, fatigue easily when walking, and have difficulty maintaining their balanceafter a perturbation. These patients are often unable to get up after a fall and maybe on the floor for an hour or more before help arrives. Deconditioning of this sortis often treatable. Resistance strength training can increase muscle mass and legstrength in people in their 80s and 90s. Drop Attacks and Collapsing Falls Drop attacks are sudden collapsing falls without loss of consciousness.Patients who collapse from lack of postural tone present a diagnostic challenge.The patient may report that his or her legs just gave out underneath; the familymay describe the patient as collapsing in a heap. Orthostatic hypotension may bea factor in some such falls. Asterixis or epilepsy may impair postural support. Acolloid cyst of the third ventricle can present with intermittent obstruction of theforamen of Monroe, resulting in a drop attack. While collapsing falls are morecommon in older patients with vascular risk factors, they should not be confusedwith vertebrobasilar ischemic attacks.