A 42-year-old man presented to a neurology clinic after having consulted multiple neurologists over many years. His complaint was of left leg weakness, buckling at the knee, and the sensation that his leg, which dragged behind him, “did not belong to him.”
All previous studies (MRI of the brain and whole spine, neurophysiology, and orthopedic examination of the knee) were normal. A previous neurologist had told him that he had functional weakness of his leg, but he remained convinced that something had been missed on the tests.
Upon examination, the patient displayed obvious left-sided Hoover sign as well as a hip abductor sign (ie, weakness of hip abduction in the affected limb, which returned to normal with contralateral hip abduction). His dragging, monoplegic gait was typical of functional paralysis.
This case, presented by Stone and Edwards1 depicts a typical presentation of conversion disorder (CD), a mystifying condition that involves a series of motor symptoms such as paralysis, tremor, pain, and gait disorder for which no medical basis is found.2 Unlike factitious disorder or malingering, symptoms are not generated to intentionally deceive others or receive some secondary gain, such as disability benefits. Instead, the symptoms are “physical manifestations of emotional distress that are not under conscious awareness or control.”2
The term “conversion disorder” has been renamed as “functional neurological symptom disorder (FNSD)” in the current Diagnostic and Statistical Manual (DSM-5).3 Diagnostic criteria are listed in Table 1.
A recent article by Tsui et al reviews the “complex” neurological and pain-related presentation of CD, as well as the diagnostic process and suggested management. The authors note that the somatic symptoms associated with the disorder can be extremely “debilitating” and that their treatment can be “difficult, protracted, and costly.” Focus on specific symptoms (eg, weakness, paralysis, psychogenic nonepileptic seizures or pain) can obfuscate research and diagnosis. In patients who present with pain, the problem is compounded because of the subjectivity of the experience of pain, and the absence of diagnostic tests.2
Assessing CD and distinguishing it from other conditions can be challenging. It can be particularly difficult for primary care providers (PCPs) to distinguish CD from neurological disorders. To shed light on diagnosis and management of CD in the primary care setting, MPR interviewed Patricia Tsui, PhD, Clinical Psychologist, Department of Anesthesiology, Chronic Pain Division, Stony Brook University, Stony Brook, NY.