OBJECTIVE: To assess the feasibility and accuracy of a drill template for the placement of a cervical pedicle screw in a single vertebral level. MATERIALS AND METHODS: A volumetric CT scan was performed on a cadaver cervical spine. Using computer software, a drill template with a predefined trajectory was constructed that was designed to match the posterior surface of the right side of the fifth cervical vertebra. A physical template was created from the computer model using a rapid prototyping machine. The drill template was used to guide drilling of a pilot hole, and a CT scan was performed to assess the accuracy of this hole. A 3.5-mm diameter pedicle screw was placed in the pilot hole. The spine was then dissected to separate the vertebrae and the trajectory of the screw was visually inspected. RESULTS: The feasibility of this patient-specific rapid prototyping technique was demonstrated. Imaging and visual inspection confirmed accurate placement of the pilot hole and cervical pedicle screw without cortical violation. CONCLUSIONS: The potential use of drill templates to place cervical pedicle screws is promising. Our initial methodology appears to provide an accurate technique and trajectory for pedicle screw placement in the cervical spine. 相似文献
Chronic, recurrent, multifocal osteomyelitis (CRMO) is an obscure disease of bone, occurring in children. It appears to be an inflammatory condition with no obvious microbiological cause. Current treatments of antibiotics and anti-inflammatory medication appear to have limited success. This case report looks at two separate cases of CRMO where partial resection of the affected bone—the clavicle—leads to complete resolution of symptoms and regrowth of the excised bone. 相似文献
Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is a syndrome characterized by severe, strictly unilateral short-lasting (between 5 and 240 seconds) pain localized to orbital, supraorbital, and temporal areas, accompanied by ipsilateral conjunctival injection and lacrimation. It represents 1 of 3 primary headaches classified as trigeminal autonomic cephalalgias (TACs). Although its prevalence is extremely small, SUNCT patients may present at dental offices seeking relief for their pain. It is important for oral health care providers to recognize SUNCT and render an accurate diagnosis. This will avoid the pitfall of implementing unnecessary and inappropriate traditional dental treatments in hopes of alleviating this neurovascular pain. The following article is part 3 of a review on TACs and focuses on SUNCT. Aspects of SUNCT, including epidemiology, genetics, pathophysiology, clinical presentation, classification and variants, diagnosis, medical management, and dental considerations are discussed. 相似文献
Accumulating evidence suggests that antipsychotics (APs) that lead to sustained blockade of dopamine D(2) receptors are more likely to induce acute extrapyramidal side effects (EPS) compared to APs that only occupy D(2) receptors transiently. It is unclear, however, whether a similar relationship exists for long-term AP-induced motoric side effects like tardive dyskinesia (TD). The objective of this study was to ascertain whether transient (via daily subcutaneous (s.c.) injections) vs continuous (via osmotic minipump) AP-induced D(2) receptor occupancy differentially affects the development of haloperidol-induced vacuous chewing movements (VCMs), an animal model of TD. Six groups of 12 rats received 0.1, 0.25, or 1 mg/kg of haloperidol or vehicle (n=36) via osmotic minipump (to provide within-day sustained) or daily s.c. injection (within-day transient) for 8 weeks. VCMs were measured on a weekly basis and D(2) occupancy levels were measured in vivo using [(3)H]-raclopride at the end of the experiment. Minipump-treated rats developed HAL dose-dependent D(2) occupancies of 0.1 mg/kg/day (57%), 0.25 mg/kg/day (70%), and 1 mg/kg/day (88%). S.C.-treated rats also developed HAL dose-dependent D(2) occupancies of 0.1 mg/kg/day (83% peak, 3% trough), 0.25 mg/kg/day (89% peak, 0% trough), and 1 mg/kg/day (94% peak, 17% trough). A total of 43% of rats given 0.25 and 1 mg/kg/day of HAL via minipump developed high VCMs compared to only 8% of the rats given the same doses via daily s.c. injections. The 0.1 mg/kg dose did not give rise to VCMs beyond vehicle levels regardless of the route of administration. These findings support the contention that D(2) occupancy levels induced by chronic HAL must be high and sustained through the day before significant risk of VCMs, and perhaps also TD, emerges. 相似文献
OBJECTIVES: Local anaesthetic infiltration into the carotid sinus during carotid endarterectomy (CEA) has been recommended to minimise blood pressure fluctuations but its use remains controversial. The aim of this meta-analysis was to determine whether intra-operative administration of local anaesthetic reduces the incidence of haemodynamic instability following CEA. MATERIALS AND METHODS: A search of the Medline, Pubmed and Embase databases and the Current Controlled Trials register identified four trials, which met the pre-defined inclusion criteria for data extraction. Pooled odds ratios with 95 per cent confidence intervals (c.i.) for the development of post-operative hypotension and hypertension were calculated using a random-effects model. RESULTS: Outcomes of 432 patients were studied. Local anaesthetic blockade of the carotid sinus was associated with a pooled odds ratio of 1.25 (95 per cent c.i. 0.496 to 3.15); p=0.216) and 1.28 (95 per cent c.i. 0.699 to 2.33; p=0.428) for the development of post-operative hypotension and hypertension respectively. Although none reach significance there was a trend towards increased risk of developing a complication in those patients who received local anaesthetic. CONCLUSIONS: There are insufficient data to determine the role of intra-operative local anaesthetic administration in reducing post-operative blood pressure lability following CEA. Conversely, the possibility of harm cannot be excluded on the basis of the currently available data. 相似文献
Background: Primary afferent nociceptor sensitization and its accompanying spontaneous discharge are believed to be the proximate cause of the spontaneous pain and hypersensitivity that follow an acute tissue injury. Evidence for this comes almost entirely from studies limited to the first few minutes to an hour or two after injury, when the inflammatory reaction to injury has just begun. However, there is evidence that inflammatory pain mechanisms differ from acute pain mechanisms and that the mechanisms that drive and modulate inflammatory pain may evolve over time.
Methods: The authors surveyed spontaneous afferent discharge in rats with hind paw inflammation evoked by complete Freund adjuvant over the entire 14 days of the inflammatory pain condition, as determined in parallel experiments assessing allodynia and hyperalgesia.
Results: Inflammation-evoked heat hyperalgesia, mechanoallodynia, and mechanohyperalgesia began within hours, persisted until at least day 7, and resolved by day 14. A large percentage (23%) of A fibers had spontaneous discharge 2 days after inflammation, but the incidence was much reduced (to 7-9%) by 7 and 14 days. At all times, the A-fiber discharge frequency was low (<3.0 Hz) or very low (<0.3 Hz). A large percentage (24%) of C fibers had spontaneous discharge 2 and 7 days after inflammation, but this also declined to near control levels by day 14; C-fiber discharge frequency was also always low (most at 0.3-1.0 Hz). 相似文献