Restoration of vestibular function: basic aspects and practical advances for rehabilitation

Background: Normal balanced functioning of the human vestibular system is required to achieve an upright stance and locomotion, head and eye stabilization and internal spatial representation; any lesion in this system will disrupt these functions. Scope: This review synthesizes previous work performed by the author and his research group in both animal models and vestibular defective patients over the last three decades. The author presents both an updated view on the basic mechanisms underlying the two main theories of vestibular compensation and his views on the principles that should guide management and rehabilitation of patients with vestibular loss. Findings: Static deficits, following the loss or disruption of vestibular functions, are fully compensated; this is explained by the vestibulocentric theory that suggests different plastic changes occurring in the vestibular nuclei complexes. In contrast, dynamic deficits remain poorly compensated; the restoration of dynamic vestibular functions results from substitution processes and vicarious strategies. The practical advances in the rehabilitation of vestibular defective patients are as follows: (1) perform rehabilitation at an early stage; (2) favour active retraining; (3) do not use stereotyped rehabilitation programs but adapt exercises to the patients; (4) examine patients in standardized environments; (5) use both static and dynamic tests; and (6) avoid drugs with sedative effects (or limit them to the very acute stage only) and prescribe those accelerating the recovery process (e.g. betahistine dihydrochloride). Conclusion: Recovery of vestibular function is greatest when early active retraining and adequate pharmacological treatments are used in combination.