Biomedical subjects

Michael W Ardagh

Publications and source records attributed to Michael W Ardagh.

5 recordsLinked to original sources

PubMed2007

Mild head injury--a close relationship between motor function at 1 week post-injury and overall recovery at 3 and 6 months.

Based on previous findings of impaired eye and arm motor control after mild closed head injury (CHI), this study examined whether early eye and arm motor function, and the level of post-injury cerebral dysfunction manifested in motor control, relates systematically to recovery at 3 and 6 months after mild CHI. At 1 week post-injury, we assessed oculomotor function, upper-limb visuomotor performance, and cognitive status in 37 mild CHI patients. Re-examination at 3 and 6 months determined outcome in terms of postconcussional symptoms and performance of everyday tasks, as assessed by the Rivermead Postconcussion Symptoms Questionnaire, the Rivermead Head Injury Follow-up Questionnaire and the SF-36 Health Survey. We then examined the association of early motor function, cognitive status and self-reported health condition with outcome using linear regression. Motor-based regression models explained a high proportion of the variance in outcome (70-89%), with motor function at 1 week being more closely related to outcome at 3 and 6 months than early psychometric assessment (13-32%) or self-reported health status (54-79%). These motor-based models incorporated subcortical/subconscious motor functions alongside motor functions that are subject to volitional control and are primarily mediated by frontal, parietal and temporal cortical brain regions. Early assessment of eye and arm motor function may help in improving accuracy of outcome prediction after mild CHI. Such assessment may assist in the better targeting of early health care intervention and help decrease head-trauma-related morbidity and rehabilitation costs.

Adolescent↗

PubMed2006

Motor deficits and recovery during the first year following mild closed head injury.

OBJECTIVE: This study examined motor impairments over 1 year following mild closed head injury (CHI). It is the first study to serially assess long-term oculomotor and upper-limb visuomotor function following mild head trauma. METHODS: Thirty-seven patients with mild CHI and 37 matched controls were compared at 1 week, 3 months and 6 months and 31 available pairs at 12 months post-injury on measures of saccades, oculomotor smooth pursuit, upper-limb visuomotor function and neuropsychological performance. Symptomatic recovery was sampled using the Rivermead Postconcussion Symptoms Questionnaire. RESULTS: At 1 week, the group with CHI reported high levels of post-concussional symptoms and exhibited prolonged saccade latencies, increased directional errors, decreased saccade accuracy and impaired fast sinusoidal smooth pursuit concomitant with increased arm movement reaction time, decreased arm movement speed and decreased motor accuracy on upper-limb visuomotor tracking tasks. Neuropsychological testing identified deficits only in verbal learning and speed of processing while attention, short-term/working memory and general cognitive performance were preserved. At 3 and 6 months, the group with CHI continued to show deficits on several oculomotor and upper-limb visuomotor measures in combination with some deficits on verbal learning and improved, yet abnormal, levels of post-concussional symptoms. At 12 months, the group with CHI had no cognitive impairment but residual deficits in eye and arm motor function and continued to show elevated levels of post-concussional symptoms. CONCLUSIONS: The findings indicate that multiple motor systems are measurably impaired up to 12 months following mild CHI and that instrumented motor assessment may provide sensitive and objective markers of cerebral dysfunction during recovery from mild head trauma independent of neuropsychological assessment and patient self-report.

Adolescent↗

PubMed2005

Local anaesthetic infiltration increases the accuracy of assessment of ulnar collateral ligament injuries.

OBJECTIVE: To assess the effectiveness of a systematic examination of the ulnar collateral ligament (UCL) of the thumb metacarpophalangeal joint (MCPJ) prior to and post infiltration of local anaesthetic. METHODS: During the study period from 24 October 2001 to 22 February 2002, 51 patients with clinical signs suggestive of UCL injuries were identified prospectively from initial ED attendances and attendances at a subsequent review clinic. Patients were formally assessed a mean of 6.6 days post injury. A single ED Senior House Officer carried out examination before and after direct infiltration of local anaesthetic around the site of injury. Stress radiography was also performed as the 'gold standard' diagnostic test of UCL instability. RESULTS: Forty-seven patients were enrolled in the study. When reviewed by the single observer, examination prior to and post local anaesthetic infiltration revealed a degree of joint stability in 28% (95% CI 16-43%) and 98% (95% CI 88-100%) cases, respectively, compared to the gold standard. Post infiltration, this technique had a specificity of 100% (95% CI 94-100%) and a sensitivity of 87.5% (95% CI 74-95%) (P < 0.001). Stress radiography offered additional information in one patient. A total of eight patients previously underdiagnosed in the ED were found to have unstable thumb MCPJs. CONCLUSION: This simple technique improves assessment of suspected UCL injuries approximately 1 week post injury. Further studies are indicated to determine its effectiveness in the ED immediately post injury.

Adolescent↗

PubMed2004

Eye movement and visuomotor arm movement deficits following mild closed head injury.

Based on increasing evidence that even mild closed head injury (CHI) can cause considerable neural damage throughout the brain, we hypothesized that mild CHI will disrupt the complex cerebral networks concerned with oculomotor and upper-limb visuomotor control, resulting in impaired motor function. Within 10 days following mild CHI (Glasgow Coma Scale 13-15, alteration of consciousness <20 min), we compared 30 patients (15-37 years) and 30 matched controls on different types of saccades, oculomotor smooth pursuit (sine and random), upper-limb visuomotor performance and several neuropsychological tests known to be sensitive to head trauma. Simple reflexive saccades were not impaired, whereas, on the antisaccade task, the CHI group demonstrated prolonged saccadic latencies, a marginally higher number of directional errors and poorer spatial accuracy. The CHI group exhibited more directional errors and impaired motor accuracy on memory-guided sequences of saccades and produced fewer self-paced saccades within 30 s. Most measures of sinusoidal and random oculomotor smooth pursuit showed no deficits, with the exception of a prolonged lag on random smooth pursuit in the CHI group. While arm movement reaction time and arm steadiness were not impaired, the CHI group showed decreased arm movement speed and decreased upper-limb motor accuracy. Conversely, after controlling for IQ, the CHI group had few head trauma-related neuropsychological deficits. These results indicate that multiple motor systems can be impaired following mild CHI and that this can occur independently of neuropsychological impairment. Our study also indicates that quantitative tests of oculomotor and upper-limb visuomotor function may provide sensitive markers of cerebral dysfunction, suggesting the potential use of such tests to supplement patient assessment. To our knowledge, this study is the first to demonstrate the presence of oculomotor or visuomotor deficits following mild CHI.

Adolescent↗

PubMed2003

A telephone advice line does not decrease the number of presentations to Christchurch Emergency Department, but does decrease the number of phone callers seeking advice.

AIM: To describe the effect of a pilot national telephone advice service (Healthline) on a public hospital emergency department. METHODS: We prospectively gathered information from the Christchurch Hospital Emergency Department (ED) computer- and non-computer-based information systems, for a six-month period during the operation of Healthline. We compared the data with five earlier periods when Healthline was not running. In addition, Healthline collected and analysed data from call log information. RESULTS: There was a small increase (1.1%) in ED attendance during the study period. Patients referred by Healthline had a similar triage distribution to the general ED population, but a lower admission rate (29% vs 47%). Telephone calls to the ED dropped dramatically during the study period. CONCLUSIONS: Healthline had little effect on overall ED census and appeared to refer patients with similar acuity to the general ED census. It decreased the workload for ED nursing staff charged with answering advice calls.

Emergency Service, Hospital↗