Chapter 024. Gait and Balance Disorders (Part 5) Falls Falls 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 as recurrent fallers. Some of these are frail older persons with chronic diseases. Recurrent falls sometimes indicate the presence of serious balance impairment. Syncope, seizure, or falls related to loss of consciousness require appropriate evaluation and treatment (Chaps. 21 and 363). Table 24-3 Risk Factors for Falls, a Meta-Analysis: Summary of Sixteen 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 from retrospective studies. Source: Reprinted from Masdeu et al, with permission.The descriptive classification of falls is as difficult as the classification of gait disorders, for many of the same reasons. Postural control systems are widely distributed, and a number of disease-related abnormalities occur. Unlike gait problems that are apparent on observation, falls are rarely observed in the office. The patient and family may have limited information about what triggered the fall. Injuries can complicate the physical examination. While there is no standard nosology of falls, common patterns can be identified. Slipping, Tripping, and "Mechanical Falls" Slipping on icy pavement, tripping on obstacles, and falls related to obvious environmental factors are often termed mechanical falls. They occasionally occur in healthy individuals with good balance compensation. Frequent tripping falls raise suspicion about an underlying neurologic deficit. Patients with spasticity, leg weakness, or foot drop experience tripping falls. Weakness and Frailty Patients who lack strength in antigravity muscles have difficulty rising from a chair, fatigue easily when walking, and have difficulty maintaining their balance after a perturbation. These patients are often unable to get up after a fall and may be on the floor for an hour or more before help arrives. Deconditioning of this sort is often treatable. Resistance strength training can increase muscle mass and leg strength 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 family may describe the patient as "collapsing in a heap." Orthostatic hypotension may be a factor in some such falls. Asterixis or epilepsy may impair postural support. A colloid cyst of the third ventricle can present with intermittent obstruction of the foramen of Monroe, resulting in a drop attack. While collapsing falls are more common in older patients with vascular risk factors, they should not be confused with vertebrobasilar ischemic attacks. . Chapter 024. Gait and Balance Disorders (Part 5) Falls Falls are a common event, particularly among the elderly. Modest changes in balance function have been. classification of gait disorders, for many of the same reasons. Postural control systems are widely distributed, and a number of disease-related abnormalities occur. Unlike gait problems that. indicate the presence of serious balance impairment. Syncope, seizure, or falls related to loss of consciousness require appropriate evaluation and treatment (Chaps. 21 and 363). Table 24-3 Risk