Dizziness in Orthopaedic Physical Therapy Practice: Classification and Pathophysiology

Peter Huijbregts, PT, MSc, MHSc, DPT, OCS, MTC, FAAOMPT, FCAMT
Paul Vidal, PT, MHSc, DPT, OCS, MTC

Abstract: Dizziness is a frequent complaint in patients presenting to orthopaedic physical therapists. Differential diagnosis of dizziness is complex but essential and requires knowledge of musculoskeletal, vestibular, cardiovascular, neurological, metabolic, and psychiatric conditions, thus transcending the musculoskeletal boundaries of orthopaedic physical therapy clinical practice. Physical therapy intervention is not indicated for many causes of dizziness. Some types of dizziness present contra-indications to certain orthopaedic physical therapy interventions. This article presents a diagnostic classification system and relevant pathophysiology that may facilitate orthopaedic physical therapy diagnosis, screening, and subsequent appropriate physical therapy management or medical referral.

Key Words: Dizziness, Classification, Vertigo, Presyncope, Dysequilibrium, Other Dizziness

Health care providers are frequently confronted with patients complaining of dizziness. Dizziness accounts for 7% of physician visits for patients over the age of 451; for adults over 65, it is the number one reason to visit a physician2. Dizziness is more common in women than men3 and the prevalence of dizziness increases with increasing age4. Approximately 15 to 30% of people experiencing dizziness will seek medical attention4.

Differential diagnosis of dizziness can be quite challenging: A wide range of benign and serious conditions can cause dizziness3. To further complicate matters, patients use the word “dizziness” to mean, for example, lightheadedness, blurry vision, loss of balance, or a feeling of weakness in the legs. The term “dizziness” is also used for various sensations of body orientation and position that are frequently difficult for patients to describe5.

Dizziness may result in loss of balance and falls. Falls occur each year in 32% of people aged 65 to 74; this increases to 35% in people aged 75 to 84 and to 51% in people over 856. Falls are directly and indirectly responsible for 12% of all deaths in the geriatric population. In addition, approximately 5% of falls in the elderly result in fractures; another 5 to 10% result in serious injuries requiring medical care6. The need for knowledge regarding correct diagnosis and subsequent appropriate management of complaints of dizziness is evident.

The consistent use of a classification system may serve to minimize confusion regarding a patient’s dizziness symptoms. Patients with complaints of dizziness can be classified into four subtypes5, 7:

  1. Vertigo
  2. Presyncope
  3. Dysequilibrium
  4. Other dizziness

Vertigo is a false sensation of movement of either the body or the environment, usually described as spinning, which suggests vestibular system dysfunction3,4,8,9. It is usually episodic with an abrupt onset and often associated with nausea or vomiting7. This dysfunction can be located in the peripheral or central vestibular system8,10. Peripheral vestibulopathies account for about 35-55% of all cases of dizziness4. Central vestibular disorders are less frequent and are responsible for only about 5% of cases of dizziness4.

Presyncope is described as a sensation of an impending faint or loss of consciousness and is not associated with an illusion of movement3,7,9. It may begin with diminished vision or a roaring sensation in the ears7. This subtype of dizziness results from conditions that compromise the brain’s supply of blood, oxygen, or glucose9. The frequency reported for presyncopal dizziness varied from 2% in a dizziness clinic to 16% in an emergency room11,12. This type of dizziness may be accompanied by transient neurological signs, e.g., dysarthria, visual disturbances, and extremity weakness13,14.

Dysequilibrium is a sense of imbalance without vertigo that is generally attributed to neuromuscular problems3. It is also described as the feeling that a fall is imminent7. The unsteadiness or imbalance occurs only when erect and disappears when lying or sitting7. This subtype of dizziness may result from visual impairment, peripheral neuropathy, and musculoskeletal disturbances, and may include ataxia. Sloan et al3 cited a prevalence of 1-15% for dysequilibrium in patients complaining of dizziness.

Other dizziness is dizziness described as a vague or floating sensation with the patient having difficulty relating the specific feeling to the clinician3. It includes descriptions of vague lightheadedness, heavy headedness, or wooziness and cannot be classified as any of the three previous subtypes7. Psychiatric disorders are the main cause for this subtype and account for about 10 to 25% of dizziness cases3,5. Anxiety, depression, and hyperventilation are often at the root of this dizziness3,15. Changes in vision and tilting of the environment are included in the subtype of other dizziness, as is psychogenic or psychosomatic dizziness due to panic disorder3,16.

The classification of dizziness into these four subtypes attempts to differentiate complaints of dizziness by symptoms and pathophysiology. This classification system is challenged when an individual complains about more than one subtype of dizziness. Dizziness may result from disorders in the musculoskeletal, vestibular, cardiovascular, neurologic, and metabolic systems as well as from psychiatric disorders4. The term “geriatric syndrome” was proposed to describe dizziness in older adults occurring as a result of multi-system impairment17. The problem with this term, though, is that it suggests that dizziness is due to old age; however, recent studies have demonstrated that dizziness is prevalent in all adult populations3,5. The system is also challenged by symptoms of ataxia, a dyscoordination or clumsiness of movement not associated with muscular weakness, which can be the result of neuromuscular, i.e., proprioceptive, disorders but also of cerebellar and vestibular disorders occurring with or without symptoms of vertigo9.

Dizziness is a frequent patient complaint in the orthopaedic physical therapy practice and can result from dysfunctions in multiple body systems. Certain types of dizziness are amenable to physical therapy (PT) interventions; others produce contra-indications to certain PT interventions, while still other causes of dizziness require medical referral. Differential diagnosis is complex but essential and requires knowledge that transcends the musculoskeletal boundaries of typical orthopaedic physical therapy clinical practice. Therefore, this article will extend its discussion of the pathophysiology of dizziness to include not only musculoskeletal but also vestibular, cardiovascular, neurologic, metabolic, and psychiatric causes for dizziness within the framework of the classification system presented above. This article is part one of a two-part series. The second article discusses the history, tests, and measures based on the classification system and pathophysiology introduced here, thus providing the practical information for the orthopaedic physical therapist on diagnosis and screening of patients with complaints of dizziness. Discussion of the anatomy and physiology of the balance control systems is not part of this series and we refer the reader to relevant texts18-26. Discussion of PT interventions is also outside the scope of these articles.

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