Recognizing a Rare Disorder: Painful Legs and Moving Toes
Abstract & Commentary
By Claire Henchcliffe, MD, PhD, Associate Professor of Neurology and Neuroscience, Weill Cornell Medical College. Dr. Henchcliffe reports she is on the speakers bureau and advisory board for Allergan and Teva; speakers bureau for Boehringer-Ingelheim, GlaxoSmithKline, and Novartis; advisory board for Merz; and is a consultant for Gerson Lehman Group and Guidepoint Global.
Synopsis: This case series of patients with painful legs and moving toes is the largest to date and describes association with female gender, peripheral neuropathy and radiculopathy, cancer, and autoimmune disorders. Neurophysiology suggests an additional central component, supporting recruitment of a spinal cord or brainstem generator.
Source: Hassan A, et al. Painful legs and moving toes syndrome: A 76-patient case series. Arch Neurol 2012;69:1032-1038.
This case series of individuals with painful legs and moving toes (PLMT) describes patients identified from the electronic medical record database at the Mayo Clinic, Rochester, MN, from 1982-2011. Inclusion required diagnosis documented in the record by a neurologist. In this 18-year period, the 76 cases identified comprised 50 (66%) women, with mean age of onset 58 years (range 24-86 years), of whom 69 (91%) had symptom onset in one or both legs, and 70/74 (95%) reported pain. Pain in both legs and arms was reported in 13%, and the majority, but not all (58%), had bilateral symptoms by the time of evaluation. None had symptoms in the arms only. Descriptions of pain were highly variable and included tingling, numbness, aching, shock, prickly, throbbing, deep, and cold. Involuntary movements, generally occurring some time after onset of pain symptoms, were varied but include wriggling, dystonia, flexion-extension, fanning, clawing, and piano-playing. The authors note medical histories of cancer in 12, hypothyroidism in 11, type 2 diabetes in seven, gastric bypass in three, low vitamin B12 level in five, but no chronic pain syndrome. Taken together, the authors count 24% as having likely autoimmune disorders (coexisting diseases including hypothyroidism, vitamin B12 deficiency, idiopathic thrombocytopenia, primary ovarian failure, and rheumatoid arthritis). Sensory peripheral neuropathy was identified in 48% upon examination, although the authors report nerve conduction abnormalities were "mild," and included radiculopathy, peripheral neuropathy, and other abnormalities. EMG recordings characterized the irregular bursts between 50 msec to 1 sec, and a range of frequency from 2-200 Hz. Most treatments recorded were aimed at pain relief. Although the degree of relief was reportedly moderate or less, 2/3 responded to tramadol, 4/22 to gabapentin enacarbil, 2/9 to pregabalin, and 3/13 to amitriptyline. For control of movement, 3/10 responded to dopamine agonist administration, and 4/17 to clonazepam.
Commentary
This is the largest case series reported to date of PLMT, a rare disorder (at the Mayo Clinic, an average of just over four patients were identified per year). Possibly related, and even more rare, conditions are "painful arms and moving fingers" and "painless legs and moving toes." This case series underscores the heterogeneity of the disorder and as such is consistent with previous case series, but serves both to draw attention to the diagnosis and to provide a platform for further study.1 In practical terms, in patients presenting with lower limb pain, PLMT needs to be considered, and all such patients should be examined with shoes and socks off for involuntary movements. Although, as the authors point out, treatment options appear limited, a diagnosis will help avoid aggressive and potentially inappropriate interventions for pain. Five of these 76 subjects underwent surgery for pain treatment without relief, and in one case a patient underwent multiple laminectomy and fusion procedures without relief. Moreover, at least in these authors' opinions, it may not be necessary to rush to suppress involuntary movements, as they report that patients were more concerned with the pain component of the disorder. The existence of neuropathy and radiculopathy in many of these subjects suggests PLMT may be a peripheral movement disorder, similar to "jumpy stumps," belly dancers' dyskinesia, or hemifacial spasm. However, the authors also point out an overlap with dystonia (some of the subjects' involuntary movements were dystonic in fact) and, in particular, dystonia associated with complex regional pain syndrome. As in prior reports, these cases suggest the possibility that longstanding pain leads to central remodeling, producing the movement disorder component of the disorder. This will await more objective studies, but in the meantime this study is a first step to attempting to dissect out the complexity of PLMT, and brings to our attention the need to consider this diagnosis in patients evaluated for leg pain.
Reference
1. Dressler D, et al. The syndrome of painful legs and moving toes. Mov Disord 1994;9:13-21.
This case series of patients with painful legs and moving toes is the largest to date and describes association with female gender, peripheral neuropathy and radiculopathy, cancer, and autoimmune disorders. Neurophysiology suggests an additional central component, supporting recruitment of a spinal cord or brainstem generator.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content