Entrapment of the lateral cutaneous nerve of the calf.

Isolated lesion of lateral cutaneous nerve of the calf (LCNC), particularly due to entrapment, is rarely reported in the literature. Patients usually present with sensory symptoms in the lateral aspect of the calf. Treatment is usually by local applications or local steroid/anaesthetic injection. We report the first case of LCNC entrapment in a 35-year-old man which is documented by nerve conduction studies. The patient had a temporary improvement following a local anaesthetic/steroid injection. Owing to the recurrence of symptoms, the patient opted for surgery. About 1 year after surgery, the symptoms disappeared completely.

Pathological yawning as an ictal seizure manifestation in the elderly.

Excessive yawning has been reported in the peri-ictal period preceding or following seizures. We describe an exceptional case of an elderly man with impairment of consciousness and paroxysmal excessive yawning. We hypothesise that this can be regarded as an autonomic seizure originating from diencephalic/brainstem structures, manifesting with yawning as an ictal phenomenon.

Cervical radiculopathy: discrepancy or concordance between electromyography and magnetic resonance imaging?

In the screening of patients with cervical radiculopathy, a relatively common finding is the discrepancy between normal needle electromyography (EMG) and abnormal MRI, or vice versa. We carried out a retrospective study to assess the relationship between needle EMG and MRI findings in the preoperative evaluation of patients with cervical radiculopathy. The records of 147 patients were reviewed; 58 patients (M = 32, F = 26; age 53 ± 9) were included in the study. Needle EMG examination was abnormal in 28 patients. MRI abnormalities were found in all 58 patients, showing degenerative changes not affecting the nerve root in 15 and foraminal stenosis affecting the nerve root in 43; in the latter, needle EMG was abnormal in 28 patients and normal in the remainder. Concordance between EMG and MRI level of abnormality was found in 71% of patients with non-dermatomal symptom distribution. Concordance between clinical level, EMG and MRI abnormality was found in 50% of patients with C5, in 70% with C6 and in 67% with C7 symptom distribution. When EMG and MRI level of abnormality was discordant, the EMG abnormalities corresponded to the clinical level of symptom distribution. The results of our retrospective study reveal that in the majority of cases of cervical radiculopathy, EMG and MRI level of abnormalities are concordant. When there is discordance between EMG and MRI findings, the EMG helps in the guidance of patient selection for surgical intervention because it provides evidence of nerve root lesion and offers a dynamic tool in the follow-up evaluation.

Asymmetry of visual function in migraine with aura: correlation with lateralisation of headache and aura.

BACKGROUND: Asymmetry of visual phenomena and headache is an important feature of migraine with aura. METHODS: This asymmetry was explored by assessment of visual illusions, hemifield spatial contrast detection (HCD) and hemifield pattern reversal visual evoked potentials (HVEPs) in 47 migraineurs with aura (MA), who were not taking prophylactic medications, and 62 controls with the same age range (16-59). RESULTS: Illusions were greater and HCD was poorer in MA than in controls. There were no group differences with respect to P100 amplitude. The longer the duration of migraine the poorer the HCD. When the aura was consistently unilateral it was associated with greater illusions, reduced HCD and reduced hemifield P100 amplitude. These findings were not related to the side of headache. CONCLUSION: The lateralised changes suggest that the visual dysfunction occurs at a cortical level, and the correlation with the side of the aura suggests that dysfunction is most likely to occur in an area of preexisting anomaly of neural function.

The value of neurophysiological and imaging studies in predicting outcome in the surgical treatment of cervical radiculopathy.

It is not always easy to predict the degree of symptomatic improvement to be expected in a patient undergoing surgery for cervical disc herniation and radiculopathy. Here we investigate whether preoperative electromyography (EMG) can help select those most likely to benefit from intervention. We prospectively evaluated 20 patients whose required operative level was unclear after clinical examination and MRI scan alone. The surgical procedures was anterior cervical interbody fusion with the AcroMed carbon fibre cage. Clinical assessment employed using validated scoring systems (Prolo functional and economic scoring system). Patients underwent MRI preoperatively, and were assessed pre and postoperatively with neurophysiological studies (NPS) including nerve conduction studies and concentric needle EMG. Patients with preoperative evidence of cervical nerve root involvement on EMG (group A, n = 8) had better outcome (P = 0.001) following discectomy and anterior fusion than patients who had no evidence of nerve root damage on EMG (group B, n = 12). Prolo mean score +/- SEM for group A was 7.375 +/- 0.3750 and for group B was 5.583 +/- 0.2876. Thus, NPS are a valuable tool in selecting patients in this subgroup for cervical surgery.