Idiopathic fluctuating dystonia: a case of foot dystonia and writer's cramp responsive to L-dopa

Management of pain in Parkinson's disease

Pain is a common symptom in Parkinson's disease (PD) and accounts for substantial morbidity in up to 80 % of patients. Despite contributing to disease-related discomfort and disability, pain in PD frequently goes underacknowledged and undertreated in clinical practice. Although the exact underlying neurophysiology is unclear, there is increasing understanding of the role of the basal ganglia in somatosensory processing, as well as involvement of additional brainstem structures and non-dopaminergic pathways; appreciation of these mechanisms has implications for treatment strategies. Categorizing painful symptoms based on their clinical description into musculoskeletal, dystonic, radicular-peripheral neuropathic and central pain categories provides a useful framework for management. Importantly, these symptoms should be evaluated in relation to motor symptoms and dopaminergic therapy. A multi-disciplinary approach is recommended as follows: physical therapy, liaison with pain management and consultations to rheumatological, orthopaedic and neurosurgical services should be considered.

Striatal deformities of the hand and foot in Parkinson's disease

Striatal deformities of the hand and foot are abnormal postures that are common in patients with advanced Parkinson's disease (PD); they can present in the early stages of PD and in other parkinsonian disorders. Over a century ago, Charcot and Purves-Stewart recognised these deformities, which cause substantial functional disability and discomfort. The term striatal is used because pathology in the neostriatum (putamen and caudate) has been suggested to cause the deformities, but the pathogenesis is unknown. Misdiagnosis of the deformities is common-particularly when they occur early and in the absence of cardinal parkinsonian signs, such as tremor, bradykinesia, and rigidity-because the hand deformities are similar to those in rheumatoid arthritis, equinovarus foot deformity typically suggests an orthopaedic problem, and toe extension may be thought to be the Babinski sign of upper-motor-neuron syndromes. Here we review the background and clinical features of these deformities to highlight these commonly unrecognised and poorly understood parkinsonian signs.

Dopa-responsive dystonia: a clinical and molecular genetic study

We have studied the GTP-cyclohydrolase 1 (GCH-1) gene in 30 patients with the diagnosis of clinically definite (n = 20) or possible (n = 10) dopa-responsive dystonia (DRD) as well as in a child with atypical phenylketonuria due to complete GCH-1 deficiency. A large number of new heterozygote mutations (seven point mutations, two splice site mutations, and one deletion) as well as a new homozygote mutation in the child with atypical phenylketonuria were detected. In addition, two previously described mutations were found in two other cases. We further extended our investigation of GCH-1 to the 5' and 3' regulatory regions and report the first detection of point mutations in the 5' untranslated region. Demethylation of CpG islands does not appear to be an important causative factor for the GCH-1 mutations in DRD. In addition, we have extended the clinical phenotype of genetically proven DRD to focal dystonia, dystonia with relapsing and remitting course, and DRD with onset in the first week of life. None of our DRD patients without a mutation in GCH-1 had the 3-bp deletion recently detected in DYT1, the causative gene for idiopathic torsion dystonia with linkage to 9q34.

Operative management of foot and ankle equinovarus associated with focal dystonia

Six surgical procedures, consisting of tendon transfers and releases, were performed in five patients with idiopathic focal dystonia involving the lower extremity. All patients were female. Surgical management was performed to correct clinically significant foot abnormalities. The goal of each procedure was functional improvement and obtaining a plantigrade foot. The SPLATT (split anterior tibial tendon transfer) procedure was performed in each foot with a flexible equinovarus foot abnormality. Follow up at a mean of 27.2 months (range, 8-40 months) yielded satisfactory clinical results without significant complications. Clinical equinovarus has not recurred after this procedure. All patients remain brace-free ambulators.

Dopa-responsive childhood dystonia: a forme fruste with writer's cramp, triggered by exercise

An 11-year-old girl was evaluated for walking difficulties and fatigue at the end of the day in the last 2 years. Handwriting was also difficult with 'cramps' after a short time of writing. Neurological examination was normal most of the time but in the evening and after exercise, an abnormal walking posture and rare dystonic movements of the foot could sometimes be seen. The mother was found to have mild parkinsonism and is asymptomatic on L-dopa. In the daughter, all symptoms and signs disappeared on L-dopa, but returned when the drug was withdrawn. The changes on- and off-treatment were documented with videofilms and computerized analysis of writing samples. The situation has been stable during a 5-year follow-up. We draw attention to this 'forme fruste' of dopa-sensitive childhood dystonia which becomes manifest with exercise and which can easily go unrecognized. We also discuss and illustrate the methods used for the analysis of writing.

Fluctuating dystonia responsive to levodopa

Four cases of hereditary progressive dystonia with diurnal fluctuation were studied. All were sporadic; three of them mimicked spastic diplegia; and the fourth showed some similarity to torsion dystonia. Emotional or cognitive disturbance, or both, was seen in three. The correct diagnosis was suggested by fluctuating signs and symptoms, which worsened towards evening, but this was reached only after many years of handicap, hospital admissions, and invasive diagnostic procedures. Typically there was a prompt, pronounced, and sustained response to moderate doses of levodopa. Sleep recordings were obtained in three patients and showed increased body movements during rapid eye movement sleep. Several close relatives had periods of increased leg movements during sleep. It is suggested that hereditary dystonia responsive to levodopa should be considered as the diagnosis in children with fluctuating signs of motor disability syndromes, simulating torsion dystonia or spastic diplegia. Polysomnographic studies may be helpful in diagnosis and may also detect early or subclinical cases.