Application Of Collar Research Articles

Two Cases of Odontoid Fracture in Preschool Children

Halo application is a standard method for cervical immobilization. However, complications may occur in children because of their thin skull and immature bone. The authors report two cases of odontoid fracture in preschool children treated with a Minerva cast. Two 4-year-old children sustained displaced odontoid fractures in motor vehicle accidents. The fractures were immediately reduced and immobilized using a Minerva cast, followed by the application of a soft collar. By the 1-year follow-up, uneventful bone union had occurred, and the children were able to attend preschool with minimal or no neurologic deficits. The Minerva cast is a classic, inexpensive method of cervical immobilization and is still useful for this kind of fracture. Immediate reduction and immobilization with a Minerva cast is a viable option for displaced odontoid fractures in preschool children.

Diverse effects of calcium channel blockers in the collar model Zeliha

Objective — Calcium channel blockers (CCBs) are among the most frequently prescribed cardiovascular drugs. It has been shown that these drugs have antiatherosclerotic effects in both experimental and clinical settings. However, calcium channel blockers have markedly different chemical structures and different effects on the cardiovascular system.We investigated the effect of CD-832, a Ca+2 channel antagonist, on collar-induced intimal thickening, as well as accompanied reactivity changes in rabbit carotid artery.Methods and results — Rabbits received 5 mg/kg/day CD-832 or vehicle (polyethylene glycol, 0.5 ml/kg/day) intramuscularly for a week before and 2 weeks after the collar application. Histological and isometric force measurements were performed in segments from sham and collared carotid arteries. A three-week treatment with CD-832 did not inhibit the intimal thickening caused by perivascular application of a silicone collar. Potassium chloride (KCl), phenylephrine, 5-hydroxytryptamine (5-HT, serotonin) and histamine induced concentration-dependent contractions in both sham-operated (sham) and collared arteries. Collar-induced attenuations in maximum KCl, histamine, phenylephrine and 5-HT contractions were not affected by CD-832. Collaring caused an increase in pD2 values of 5-HT and a decrease in those of phenylephrine, histamine and acetylcholine. CD-832 did not affect the altered sensitivity to these agonists.Conclusions — These results demonstrate that, in rabbit carotid artery, CD-832 did not inhibit the collar-induced intimal thickening and did not affect the accompanying changes in vascular reactivity

Reduction in mouth opening with semi-rigid cervical collars

Reduced mouth opening may be a major contributing factor to the deterioration in the view obtained at laryngoscopy when a semi-rigid cervical collar is in place. We set out to assess the degree to which mouth opening is restricted by a cervical collar. We measured maximal inter-incisor distance in 52 volunteers. It was measured again after application of each of three appropriately sized semi-rigid cervical collars (Stifneck, Miami J, and Philadelphia). Inter-incisor distance was significantly reduced by the application of a cervical collar [No collar 41 (7) mm-mean (SD); Stifneck 26 (8) P<0.0001; Miami J 29 (9) P<0.0001; Philadelphia 29 (9) P<0.0001]. There was a wide and unpredictable variation between subjects in the reduction in mouth opening and a significant proportion had an inter-incisor distance of 20 mm or less (Stifneck, 25%; Miami J, 21%; Philadelphia, 21%). Application of a semi-rigid cervical collar can significantly reduce mouth opening. This could hinder definitive airway placement. Our results support removing the anterior portion of the collar before attempts at tracheal intubation.

Effect of hair and clothing on neck immobilization using a cervical collar

An important step during spine immobilization is application of a cervical collar. Clothing or hair covering the neck may impinge on this process. The purpose of this study was to evaluate the effect of clothing and hair covering the neck on immobilization using a cervical collar. Study participants were 18 female volunteers with long hair aged 20 to 28 years. Cervical range of motion (ROM) was tested in 6 directions (flexion, extension, right and left lateral bending, right and left axial rotation) using a cervical ROM (CROM) device. After measuring unrestricted ROM (no cervical collar), a 1-piece rigid cervical collar was placed the neck (1) covered by hair and clothing; (2) covered by clothing; (3) covered by hair; or (4) uncovered. Range of motion was retested under all 4 conditions. Data were compared using crossover-design analysis of variance ( P < .05 statistically significant). Range of motion in all directions was significantly restricted by cervical collar placement under all conditions. Unrestricted ROM in all directions ranged from 41.50° (7.25°) to 70.76° (15.4°). In contrast, ROM with a cervical collar under the 4 conditions in all directions ranged from 10.80° (5.10°) to 18.81° (7.37°). We were unable to detect any significant differences in ROM between the 4 conditions. Our data suggest that long hair and clothing, which cover the neck, do not alter the effectiveness of cervical collar immobilization as measured by the cervical ROM device.

Application of collar to control scouring around rectangular bridge piers

Various methods have been attempted to control scouring around bridge piers, such as using riprap, slots through the pier, a group of small piles in front of the pier, and collars. Following successful application of collars on circular piers for reduction of scouring, in this work the effectiveness of collars on rectangular piers was tested. Experiments were carried out in the threshold of sediment motion with piers aligned and skewed at 5° and 10° to the flow, and with collars of different widths and at various elevations. It was found that wider collars at lower levels are more effective and that effectiveness of collars reduces by increasing the skewness of the pier. Maximum reduction of scouring was 74, 56 and 35% for a collar with a width equal to the pier width at streambed elevation when pier was aligned, skewed at 5° and skewed at 10° to the flow respectively.

石灰沈着性頚長筋炎の一例

Calcific tendinitis of the longus colli should be recognized as one of the causes of acute neck pain. It is induced by inflammation of the longus colli muscle following deposition of calcified particles. Although the clinical presentation may mimic more serious disorders such as retropharyngeal abcess, diagnosis can be easily established by image analysis including plain X ray, CT, and MRI. The case was a 22-year-old woman who complained of cervical stiffness due to acute nuchal pain. Plain X-ray and CT showed amorphous calcification localized in the caudal portion of the anterior arch of C1. MRI revealed diffuse swelling of the longus colli muscle as the signal intensity changes, especially in T2 weighted image. She was treated by medication with NSAIDs and local rest using neck collar application. After nine days, neck pain gradually decreased and the X-ray on day 30 showed disappearance of calcification.

Management of suspected cervical spine injuries – the paediatric perspective

Paediatric cervical spine immobilisation and management is one of the most difficult tasks to master in the paediatric trauma population. The Royal Children's Hospital – Melbourne has admitted 54 patients with diagnosed cervical spine injuries since January 1999. The management of such patients admitted to acute care facilities with suspected cervical spine injuries is inconsistent and at times sub-optimal. Management controversies centre around, application of cervical collars, clearance of the c-spine, patient movement and general care principles. In an endeavour to address these issues, the Royal Children's Hospital Trauma Service, in conjunction with the Emergency Department developed cervical spine guidelines. Teams consulted in the formulation of these guidelines included, Emergency Department, Intensive Care Unit, Orthopaedics, Neurosurgery, Radiology and General Surgery. These guidelines were developed as a clinical tool to guide management and standardise the approach of care for these patients. Specifically, the guidelines address: immobilisation of the paediatric cervical spine; radiology; clearing the cervical spine of injury; suspected or proven cervical spine injury; guidelines for times to fitting Philadelphia collar; ongoing care.

Effect of cervical hard collar on intracranial pressure after head injury.

Patients suffering head trauma are at high risk of having a concomitant cervical spine injury. A rigid cervical collar is usually applied to each patient until spinal stability is confirmed. Hard collars potentially cause venous outflow obstruction and are a nociceptive stimulus, which might elevate intracranial pressure (ICP). This study tested the hypothesis that application of a hard collar is associated with an increase in ICP. A prospective series of 10 head-injured patients with a postresuscitation Glasgow coma scale score of nine or less had ICP measurements before and after cervical hard collar application. Nine out of 10 patients had a rise in ICP following application of the collar. The difference in pre- and postapplication ICP was statistically significant (P < 0.05). Early assessment of the cervical spine in head-injured patients is recommended to minimize the risk of intracranial hypertension related to prolonged cervical spine immobilization with a hard collar.

The effects of rigid collar placement on intracranial and cerebral perfusion pressures.

Rigid collars are routinely used to immobilise the cervical spine during early management of trauma victims until spinal injury is excluded. Spinal injuries commonly coexist in patients with severe head injury, and there is still uncertainty as to whether application of a rigid collar may adversely affect intracranial pressure. The aim of this study was to examine this effect by applying rigid collars to patients with traumatic head injury. The results showed a significant rise from the baseline intracranial pressure when the collars were applied (mean rise = 4.6 mmHg, p < 0.0001). The mean rise in intracranial pressure was greater in those patients with a baseline intracranial pressure > 15 mmHg compared to those with a baseline intracranial pressure < 15 mmHg (p < 0.05). Since there was no significant change in cardiorespiratory parameters during this time, venous compression in the neck seems a likely explanation for the effect observed. These findings suggest that in head-injured patients, rigid collars should be removed as soon as cervical spine injury has been excluded or, if this is delayed, an alternative method of spinal stabilisation considered.

Collar and cuff sling (Welwyn sling): a modified use of the collar and cuff in stabilizing the injured shoulder.

A modified application of collar n cuff is demonstrated. This can provide additional support to the shoulder, particularly preventing external rotation.

Traumatic spondylolisthesis of the axis: treatment rationale based on the stability of the different fracture types.

Thirty-nine consecutive patients, 22 male and 17 female with an average age of 37.6 years, with traumatic spondylolisthesis of the axis were reviewed. The cause of injury in 75% of the patients was a road traffic accident. The fractures were classified according to Effendi et al., the type II fractures were further divided into three subgroups: flexion, extension and listhesis injuries. There were 10 type I (25.7%) and 29 type II fractures (74.4%); of these, 12 (30.8%) were classified as flexion-type, 2 (5.1%) as extension-type and 15 (38.5%) as listhesis-type. We did not identify any case of type III injury. Overall, 43.5% of the patients had sustained a significant head or chest trauma, with the highest incidence for type II listhesis injuries. Significant neurological deficits occurred in four patients (10.3%); in all four,the fracture was classified as a type II listhesis. All ten type I injuries were successfully treated with a cervical orthosis. Ten of the 12 type II flexion injuries demonstrated significant angulation. Two were treated with internal stabilisation, in seven with a halo device and one with a minerva plaster of Paris (PoP). Healing was uneventful in all ten patients. For the remaining two stable type II flexion injuries, application of a hard collar was adequate, as was the case for the two stable type II extension injuries. Six of the 15 type II spondylolisthesis injuries underwent primary internal stabilisation, and healing was uneventful in all cases. In four (44.4%) of the nine injuries that were primarily treated with a halo device/minerva PoP, secondary operative stabilisation had to be performed. The classification of Effendi et al. provides a complete description of the different fractures. However, further distinction of the type II injuries regarding their stability is mandatory. Type II spondylolisthesis injuries are unstable, with a high number of associated injuries, a great potential for neurological compromise and significant complications associated with non-operative treatment. The majority of type II extension and type II flexion injuries can be successfully treated with nonrigid external immobilisation.

The organization and control of grooming in cats

Grooming in small felids has received little attention compared with grooming in rodents, bovids and primates where grooming is also common. This study set out to describe the general pattern, time budget and degree of cephalocaudal sequencing of self-oral grooming in the domestic cat. In 11 cats confined for the purposes of videotaping, sleeping and resting accounted for 50% of the time budget. Oral grooming, 91% of which was to multiple body regions, accounted for 4% of the overall time budget or 8% of non-sleeping/resting time. Scratch grooming, always directed to single regions, occupied about 1/50 of the time of oral grooming. There was a moderate and significant cephalocaudal trend to grooming. An increased likelihood for oral grooming to follow periods of sleep or rest was indicated by a significant negative correlation between sleep/rest duration and latency to the subsequent grooming bout. The effect of enforced deprivation of grooming on the subsequent occurrence of grooming was explored by the 3-day application of Elizabethian collars, which prevented oral grooming or control collars that did not prevent grooming. In the 12 h immediately after removal of the Elizabethian collars, oral grooming increased by 67% and scratch grooming by 200% compared with the grooming rate after removal of control collars. By the second 12 h, the apparent catch-up effect of grooming had disappeared. The occurrence of cephalocaudally-directed, multiple-region oral grooming and deprivation-enhanced grooming would appear to represent aspects of a central control mechanism for the organization and regulation of grooming.

Juvenile muscular atrophy of distal upper extremity (Hirayama disease).

This disease is characterized by initially progressive muscular weakness and wasting of the distal upper limb(s) in young people predominantly in men, followed by a spontaneous arrest within several years. This disease has been thought to be separate from motor neuron diseases, yet some authors still consider the illness a variant of motor neuron disease. However, the pathological evidence of ischemic changes in the lower cervical anterior horn should facilitate differentiation of the disorder from degenerative motor neuron disease. Recent radiological investigations proved compressive flattening of the lower cervical cord due to forward displacement of the cervical dural sac and spinal cord induced by neck flexion. These findings suggest that sustained or repeated neck flexion may cause ischemic changes in the cervical anterior horn. Application of a cervical collar to minimize neck flexion prevents progressive muscular weakness in an early stage of the disease.

Involvement of 5-HT1B receptors in collar-induced hypersensitivity to 5-hydroxytryptamine of the rabbit carotid artery.

In humans intimal thickening is aprerequisite of atherosclerosis. Application of a silicone collar around the rabbit carotid artery induces an intimal thickening but in addition it increases the sensitivity to the vasoconstrictor action of serotonin (5-hydroxytryptamine, 5-HT). The 5-HT receptors involved in collar-induced hypersensitivity to 5-HT were investigated using several agonists and antagonists. One week after placement of collars around both carotid arteries of anaesthetized rabbits, rings (2 mm width) from inside (=collar) and outside (=sham) the collars were mounted in organ baths (10 ml) for isometric force measurements at 6 g loading tension. Collared rings were more sensitive to the contractile effect of 5-HT (7.6 fold) and 5-carboxamidotryptamine (31 fold, 5-CT, 5-HT1 agonist) in cumulative concentration response curves. Sumatriptan (5-HT1B/1D agonist) caused concentration-dependent constrictions in collared rings only. Collar placement did not significantly alter pA2 values (Schild regression) or apparent pKb values (non-linear regression) of spiperone and methysergide (mixed 5-HT2A/5-HT1 antagonists) or ketanserin and ritanserin (5-HT2A antagonists), indicating unchanged binding characteristics of the 5-HT2A receptor. However, the reduced slope of the Schild regression pointed to a heterogeneous receptor population in collared rings. In contrast, the apparent pKb value of methiothepin (5-HT1B antagonist) was significantly reduced by collar placement, and its antagonism shifted from non-surmountable in sham rings to surmountable in collared segments. Taken together, this study demonstrates that the serotonergic receptor involved in the hypersensitivity to 5-HT of rabbit collared carotid artery is a 5-HT1B receptor subtype.

Magnetic resonance imaging evaluation of the cervical spine in the comatose or obtunded trauma patient.

Confirmation of cervical spine stability is difficult to obtain in the comatose or obtunded trauma patient. Concurrent therapies such as endotracheal intubation and the application of rigid cervical collars diminish the utility of plain radiographs. Bony as well as supportive soft-tissue structures must be evaluated before the cervical spine can be determined to be uninjured. Although major injuries to extradural soft-tissue structures in the awake trauma patient are frequently excluded by physical examination, when the patient is obtunded the physical examination may be unreliable. Therefore, an enhanced diagnostic method for the evaluation of soft-tissue injury is desirable. The authors conducted a study in which magnetic resonance (MR) imaging was used as such a method to assess posttraumatic spinal stability in the comatose or obtunded patient. Early, limited (sagittal T1- and T2-weighted) MR imaging was performed posttruama in 121 patients to assess soft-tissue injury. In all patients the mechanism of injury potentially could be associated with cervical spine instability, and each patient was endotracheally intubated because of head injury or severe multisystem injuries. All patients underwent imaging studies within 48 hours of injury and were either treated or cleared and spinal precautions were discontinued. Patients were excluded from this study if they had an obvious cervical spine injury identified on the initial radiographic studies or if they were determined to be too medically unstable to undergo MR imaging within the acute period (<48 hours postinjury). Thirty-one (25.6%) of the 121 patients were found to have sustained significant injury to the paravertebral ligamentous structures, the disc interspace, or the bony cervical spine. These injuries were undetected by plain radiography. The other 90 patients (74.4%) were determined within 48 hours not to have sustained a soft-tissue injury. Eight patients (6.6%) ultimately underwent surgery to treat the cervical spine injury, and MR imaging was the first test that identified the injury in each of these patients. There were no complications related to imaging procedures. Sagittal T1- and T2-weighted MR imaging appears to be a safe, reliable method for evaluating the cervical spine for nonapparent injury in comatose or obtunded trauma patients. In the early postinjury period, nursing and medical care are thereby facilitated for patients in whom occult injury to the spine is ruled out and for whom those attendant precautions are unnecessary.

Cutaneously applied 4-hydroxytamoxifen is not carcinogenic in female rats.

Tamoxifen is widely used to treat oestrogen-dependent carcinoma of the breast. Previous long-term studies have shown that oral administration of tamoxifen induces hepatoproliferative lesions and hepatocellular tumours in rats. 4-hydroxytamoxifen is an active metabolite of tamoxifen undergoing clinical evaluation for the treatment of various non-malignant breast diseases by topical application. In the present study, 4-hydroxytamoxifen was administered daily by cutaneous application for 101 weeks to groups of 50 female Sprague-Dawley rats at 20, 140 or 1000 microg/kg/day. The product was applied with no occlusive bandage and oral ingestion was avoided by application of an Elizabethan collar for 6 h after administration. Treatment with 4-hydroxytamoxifen was clinically well tolerated and induced changes such as decreased food consumption and body weight gain, uterine and ovarian atrophy, mucification of vaginal epithelium and reduced mammary development, all of which were attributed to its pharmacological action. Mortality was significantly lower in the treated animals. The number of animals with palpable masses was similarly reduced. The incidence of mammary tumours and hypophyseal tumours was markedly lower in 4-hydroxytamoxifen-treated animals. The incidence of chronic tubulo-interstitial nephropathies, a common cause of mortality, was also lowered. There was no evidence of a carcinogenic action of 4-hydroxytamoxifen on the liver, genital organs or skin. Plasma levels of 4-hydroxytamoxifen were stable over the duration of the study and were proportional to the administered dose, exceeding clinical plasma levels by 60-fold at the high dose-level. In conclusion, 4-hydroxytamoxifen is not carcinogenic in the rat and reduces the incidence of spontaneous mammary and hypophyseal tumours.

Laryngoscopy using the McCoy laryngoscope after application of a cervical collar: Gabbott DA. Anaesthesia. 1996;51:812–814

Laryngoscopy using the McCoy laryngoscope after application of a cervical collar: Gabbott DA. Anaesthesia. 1996;51:812–814

The effect of a rigid collar on intracranial pressure

Spinal immobilization and the application of a rigid collar to protect the neck forms an integral part of care of the injured. The very nature of collar design predisposes to vascular obstruction of blood draining from the brain and theoretically may raise intracranial pressure (ICP). We analysed this effect prospectively in a series of injured patients using the Stifneck rigid collar, the most popular collar used in the UK. Comparison of the ICP before, during and after collar application showed a significant rise ( P < 0.001), a mean rise in ICP of 4.5 mmHg, with a standard deviation of 4.1 mmHg. Insignificant changes in mean arterial pressure suggested that this effect is a response to distortion of venous drainage rather than cutaneous stimulation alone. Since head-injured patients with lowered level of consciousness form a key group who require cervical spinal immobilization it is essential that secondary insults producing raised ICP are minimized. Alternative forms of cervical spinal immobilization should be considered if collars impede venous drainage through the neck.

Angiotensin-converting enzyme inhibitors reduce neointimal thickening and maintain endothelial nitric oxide function in rabbit carotid arteries

Application of periarterial collars induced atheroma-like lesions in the carotid arteries of normocholesterolemic rabbits. Vessel segments taken from the mid-region of the collar (cuffed region) and control regions of the same artery were studied at 7 days after surgery. A group of placebo rabbits was provided ad libitum with regular tap water, and treated animals were supplied for 14 days (beginning 7 days before collar application) with water containing perindopril (daily intake of approximately 0.3 mg/kg). Perindopril treatment reduced plasma angiotensin-converting enzyme (ACE) activity by 88% but did not significantly alter arterial blood pressure or heart rate. The sensitivity of arterial rings to angiotensins I and II did not differ between control and cuffed arteries in either placebo or perindopril-treated rabbits, but in rings from both groups of rabbits the sensitivity to the vasoconstrictor action of serotonin was higher in the cuffed segments, as in previous studies. In addition, in placebo rabbits the endothelium-dependent vasorelaxant response to acetylcholine (which results from the release of nitric oxide) was weaker in cuffed arteries than in controls, whereas in the perindopril-treated animals, this impairment of relaxation was restored to the extent that, in cuffed vessels, it was no longer significantly different from the controls. Similar results were obtained in rabbits treated with another ACE inhibitor (ramipril). In contrast, acute treatment with the metabolite, perindoprilat, in vitro (1.0 microM) did not alter the response to acetylcholine in control or cuffed rings from placebo rabbits. Morphologically, vessel segments taken from the center of the cuffed artery of placebo rabbits showed a thickened intima with marked smooth muscle cell proliferation.(ABSTRACT TRUNCATED AT 250 WORDS)

Position of the cervical vertebrae during helmet removal and cervical collar application in football and hockey.

There is lack of consensus among prehospital personnel (athletic therapists, paramedics, sport physiotherapists) concerning specific aspects of initial care and assessment of injured athletes presenting signs and symptoms of a cervical spine injury (CSI). In instances of serious injury involving the head and/or spine, complicated by altered levels of consciousness, protective equipment such as helmets and shoulder pads may provide a hinderance to prompt, safe and efficient management. Specifically, there is disagreement concerning the need or advisability of removing protective head gear, as in the case of football and hockey athletes. Using the technique of fluoroscopy, the cervical spine displacement of 21 male football and hockey athletes was determined while wearing protective shoulder pads and protective head equipment at the following times (a) during helmet removal, (b) during cervical collar application, and (c) as the helmetless head was allowed to rest. Subsequent frame-by-frame video arthokinematic analysis, using computer-assisted digitization, showed significant alterations in the position of adjacent cervical vertebrae during helmet removal, cervical collar application, and head rest. Results suggest that stabilization and transportation of football and hockey athletes with suspected CSI in their respective protective equipment is recommended in order to reduce the risk of further trauma by unnecessary cervical spine motion.