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N Gravill

Publications and source records attributed to N Gravill.

4 recordsLinked to original sources
PubMed1998

[Value of neurophysiological studies in diagnostic verification of carpal tunnel syndrome].

The success of surgical treatment of carpal tunnel syndrome depends largely on correct diagnosis. Nerve conduction studies are usually recommended, especially in cases where history and clinical signs are not very clear. The aim of this study is to show whether nerve conduction studies are helpful in confirming the diagnosis. Fifty-two cases of carpal tunnel decompression (39 patients, 13 male, 26 female, mean age 54 years) were included in the study. Prior to surgery, all patients underwent standardized nerve conduction studies. One patient who developed RSD was excluded. In 33 cases the history was typical for carpal tunnel syndrome (Phalen 1966). The surgical result was classified excellent in 67% and good in 33%. Nerve conduction studies had failed to confirm the diagnosis in five cases, although duration as well as severity of symptoms did not differ from the other cases. In 18 cases the patients' history was considered atypical. Nerve conduction studies indicated carpal tunnel syndrome in 89%. The result of median nerve decompression was satisfactory in 78% (excellent in 45% and good in 33%) and unsatisfactory in 22% of the cases. Notably patients with unsatisfactory results had positive nerve conduction studies. The Phalen and Hoffmann-Tinel testing produced no false-positive results in these cases. General analysis showed that age, severity and duration of symptoms did not significantly influence the result. However, patients with atypical symptoms had a higher incidence of radiological evidence of cervical spondyloarthritis (50 versus 30% in patients with typical symptoms). The results of our nerve conduction studies indicated a sensitivity of 85% and a specificity of 92%, comparable favourably with other reports. We conclude that in patients with classical symptoms nerve conduction studies are not absolutely necessary. However, when symptoms are atypical the diagnosis cannot be based on nerve conduction studies alone. The false-positive results delivered by the nerve conduction studies may be explained with the "double crush" theory, since cervical spondyloarthritis prevailed in patients with atypical symptoms.

Carpal Tunnel Syndrome↗
PubMed1994

Presentation of colour flow maps of the peripheral circulation.

The use of continuous wave Doppler ultrasound for lower limb arterial assessment is a well established technique in most district hospitals. Patients found to have disturbances in blood flow attributable to arterial plaques are often referred for arteriographic visualization of the disease with its inherent risks and complications. The availability of colour flow mapping on modern ultrasound scanners provides a non-invasive way of detecting the size and extent of these plaques and, in some institutions, is replacing arteriography. One possible disadvantage of the use of colour flow mapping is that it does not provide a permanent record showing the relationship of the plaques to the patient's gross anatomy in the same way as arteriography. This may limit the acceptability of this technique. At Lincoln work was undertaken to develop a system for presenting images of a whole segment of a limb simultaneously along with the associated blood velocity spectrum. This was performed first by hand and then a suite of computer software was developed to automate the process. Comparisons were made between the ultrasound based images and arteriography, showing the techniques to be of similar diagnostic value. The technique provides composite images showing anatomical detail, blood flow and velocity spectra for ease of interpretation. Further studies will be undertaken in order to define patient groups where diagnostic arteriography can be avoided.

Color↗
PubMedDate not supplied

Posture control using electrical stimulation biofeedback: a pilot study.

The investigation studied the effects of biofeedback on the sitting posture of a 14 year old girl with cerebral palsy. The subject's posture was quantified using a video analysis technique which established the threshold of poor posture at 30 degrees from the vertical plane. A stimulator system was designed using an adapted drop foot stimulator and a custom made controller with a mercury tilt switch as the posture angle transducer. If posture became greater than 30 degrees tactile electrical stimulation was administered to the subject's lower back. Repetitive stimuli occurred on non-correction of posture, with a maximum of 4 consecutive stimuli, upon which an alarm was activated. 10 training sessions of 20 min duration were completed over a 4 week period, monitored using a data logger. Following initial improvement the daily results show a gradual deterioration in posture, whilst post-trial video analysis indicates a significant improvement in posture. An improved response to the alarm stimulus is observed. Reasons for these conflicting findings are discussed.

Adolescent↗