Halo Orthosis Research Articles

C2 transpedicular fixation technique in Hangman's Fracture

Objective : Traumatic spondylolisthesis of the axis, also known as hangman fractures, all cervical it accounts for 4-7% of all traumas and is the second most common axis after odontoid fractures. trauma. There are unstable fractures and the treatment options are immobilization with halo or surgery. is stabilization. By most authors, it is primarily associated with halo in patients with Type 1 and Type 2 fractures.Although external fixation and immobilization are recommended, halon is a difficult orthosis to use. Because of this, segmental motion sparing surgery provides rapid recovery in suitable patients may be an option. In the case we presented, the treatment approach in Hangman's fractures was reviewed in the literature. has been reviewed and discussed. Clinical Presentation: Our case, after AITC, with Levin Edwards Type 1A Hangman fracture, A 40-year-old female patient with no neurological deficits. The patient does not prefer to use a halo orthosis C2 transpedicular surgery was performed with a lag screw for motion-sparing surgery to a young patient fixation is planned. Technique: C2 transpedicular lag screw was applied to the patient with intraoperative fluoroscopy. Conclusion: C2 transpedicular fixation with Lag screw, according to posterior segmental stabilization a more minimally invasive and motion-sparing surgery, faster recovery time may be preferred to traditional posterior stabilization methods in selected patient groups due to The patient who did not prefer the use of orthoses due to the social disadvantages of immobilization with Halo it is a quick and cost-effective surgical option in groups with a rapid recovery time.

Complications of Halo Vest Orthosis: A Narrative Study

Background and Aim: Perry and Nickel introduced the halo vest in 1959. It is the most common immobilization device for the unstable cervical spine. In the literature review, most articles review the beneficial effects of the halo vest, and a few report its complications. This study aims to evaluate the complications associated with halo orthosis. Methods and Materials/Patients: This is a narrative study about halo vest complications. To provide up-to-date information, we reviewed the articles written about halo complications. All relevant articles were retrieved from Google Scholar, Medline, PubMed, etc., using the keywords of “halo vest orthosis”, “unstable cervical spine fracture”, “halo vest complications”, “halo vest immobilization”, “pin-site-related complications”, and “vest-related complications”. Afterward, we reviewed and critically analyzed the articles. Results: At first, the halo vest was used for postoperative paralyzed poliomyelitis patients, and later, it was also used for traumatic injury of the cervical spine or postoperatively in cervical spine reconstructive surgery. Compared to other orthoses, the halo vest provides a more effective external fixation and maintains normal anatomic alignment of the cervical spine without impacting jaw motion and resulting in eating problems. However, it has many temporary complications. To prevent halo vest complications, experienced people should apply it, and the patients should be regularly followed up for early detection and treatment of complications. Conclusion: Our review is the starting point for the evaluation and investigation of halo vest complications. Because of the high incidence of pin loosening and infection, it is better to evaluate the design and application of halo pin. Since the initial design of the halo vest, only its superstructure has been redesigned without any significant change in other parts of it.

Conservative Treatment of Hangman Variant Fractures.

This is retrospective cohort study. Investigate the stability of patients with hangman variant fractures and outcomes of treatment with external immobilization. Traumatic spondylolisthesis of the axis (C2) with the fracture extending into the vertebral body has been incompletely characterized. Small case series have showed high rates of neurological injury and cite difficulty treating closed due to greater instability secondary to extensive ligamentous injury. Retrospectively, all patients admitted to a level 1 trauma center from 2004 to 2015 with acute C2 fractures were identified and classified based on computed tomographic imaging. Study cohort included patients with anterior translation <5 mm and C2-3 angulation <15 degrees that were followed to conclusion of treatment. In total, 107 hangman's variant fractures (14.5%) were identified from a database of 735 acute C2 fractures. In total, 106 of the 107 patients displayed no neurological injury related to the cervical spine at the time of presentation. A total of 63 patients met the inclusion criteria and were followed as outpatients until collar or halo vest removal. All fractures progressed to union without progressive displacement or late neurological injury. No difference was observed in radiographic outcome between patients treated in a hard collar versus halo orthosis. Although widely considered a difficult fracture to treat with closed means, hangman variants are relatively neurologically benign injuries with low incidence of ligamentous injury. Fractures with <5 mm of horizontal translation and 15 degrees of angulation can be treated with external immobilization. Our results suggest no advantage of halo immobilization versus hard collar orthosis.

A Systematic Review of the Treatment of Geriatric Type II Odontoid Fractures.

Odontoid fractures are the most common cervical spine fracture in the geriatric population; however, the treatment of type II odontoid fractures in this age group is controversial. To compare the short-term (<3 months) mortality, long-term (≥12 months) mortality, and complication rates of patients >60 years of age with a type II odontoid fracture managed either operatively or nonoperatively. We performed a systematic review of literature published between January 1, 2000, and February 1, 2015, related to the treatment of type II odontoid fractures in patients >60 years of age. An analysis of short-term mortality, long-term mortality, and the occurrence of complications was performed. A total of 452 articles were identified, of which 21 articles with 1233 patients met the inclusion criteria. Short-term mortality (odds ratio, 0.43; 95% confidence interval, 0.30-0.63) and long-term mortality (odds ratio, 0.47; 95% confidence interval, 0.34-0.64) were lower in patients who underwent surgical treatment than in those who had nonsurgical treatment, and there were no significant differences in the rate of complications (odds ratio, 1.01; 95% confidence interval, 0.63-1.63). Surgical approach (posterior vs anterior) showed no significant difference in mortality or complication rate. Similarly, no difference in mortality or complication rate was identified with hard collar or a halo orthosis immobilization. The current literature suggests that well-selected patients >60 years of age undergoing surgical treatment for a type II odontoid fracture have a decreased risk of short-term and long-term mortality without an increase in the risk of complications.

Management of Typical and Atypical Hangman's Fractures.

Study Design Retrospective study of a prospectively maintained database. Objective Our aim was to retrospectively review management and outcomes of patients with low-grade hangman's fractures, specifically looking at differences in outcomes between collars and halo immobilization. We also studied fracture patterns and their treatment outcomes. Methods Forty-one patients with hangman's fractures were identified from 105 patients with axis fractures between 2007 and 2013. Typical hangman's fractures were defined as traumatic spondylolisthesis of the axis causing a bilateral pars interarticularis fracture. Fractures involving the posterior cortex of C2 on one or both sides or an asymmetrical pattern were defined as atypical. Results There were 41 patients with a mean age of 59 years, with 13 (31.7%) typical and 28 (68.2%) atypical fractures. There were 22 (53.6%) type 1 fractures, 7 (41.4%) type 2 fractures, and 2 (4.9%) type 2a fractures in this series. Cervical collars were used to manage 11 patients (27% of all patients with hangman's fractures) and halo orthosis was used in 27 (65.8%). Three (7.3%) patients underwent surgical fixation of the fracture. Bony union was achieved in all patients on radiologic follow-up. Permanent neurologic deficit occurred in one patient due to associated injuries. Neck pain and stiffness were reported more commonly in the atypical group, but this finding was not statistically significant. Conclusions The majority of hangman type fractures can be treated nonoperatively. We found no difference in outcomes between a rigid collar or halo immobilization for treatment of low-grade fractures. Radiologic follow-up is essential to identify cases of nonunion.

Conservative management of type II and III odontoid fractures in the elderly at a regional spine centre: A prospective and retrospective cohort study

Background. The optimal management of odontoid fractures in the elderly population is unclear and management of this group of patients is complicated by multiple co-morbidities. This study aimed to determine the outcomes after conservative management strategies were applied in this patient group. Methods. We carried out retrospective and prospective analyses of all patients with axial cervical spine injuries, at a single centre. We included patients aged over 60 years with type II and III odontoid fractures. Information was gathered on demographics, ASA grading-associated injuries and complications. The outcome measures were rates and type of union, pain and neurological functions, specifically ambulation. Results. Fifty-seven adult patients with a median age of 78 years (range 60–92 years) were included. There were 42 type II and 15 type III odontoid fractures. Three patients required surgical fixation due to displaced fractures, which could not be reduced with manual traction. Twenty-four (41%) patients were managed with a rigid pinned halo orthosis to obtain adequate reduction and immobilisation. The remaining 30 (53%) were managed in a hard cervical collar. Patients managed with a halo were significantly younger and had more associated injuries than patients managed in a collar (age: t-test = 4.05, p < 0.01, associated injuries: Chi-square = 4.38, p < 0.05). At a mean follow-up of 25 weeks, 87% of type II and 100% of type III fractures had achieved bony union or stable, fibrous non-union. There were no statistical differences in fracture type, follow-up or neurological outcomes between the halo and collar groups. However, overall more patients managed in a collar developed stable fibrous non-union than bony fusion (Fisher's exact test, p < 0.05), although this was not significant when analysed by each fracture type individually. A regression model was constructed and identified fracture type as the only independent predictor of time to union, with type III fractures healing faster than type II. Conclusions. High rates of bony union and stable fibrous non-union with a good functional outcome can be achieved in the elderly population sustaining type II or III odontoid fractures, when managed non-surgically. Halo orthosis may not offer any clear advantage over hard collar in this group. Close follow-up is needed for late complications and there must be a willingness to perform surgery if conservative measures fail.

The freedom to heal: nonrigid immobilization by a halo orthosis.

Halo orthoses present a paradox. On the one hand, the nominally rigid immobilization they provide to the head aims to remove loads on the cervical spine following injury or surgery, and the devices are retightened routinely to maintain this. On the other hand, bone growth and remodeling are well known to require mechanical stressing. How are these competing needs balanced? To understand this trade-off in an effective, commercial halo orthosis, the authors quantified the response of a commercial halo orthosis to physiological loading levels, applied symmetrically about the sagittal plane. They showed for the first time that after a few cycles of loading analogous to a few steps taken by a patient, the support presented by a standard commercial halo orthosis becomes nonlinear. When analyzed through straightforward structural modeling, these data revealed that the nonlinearity permits mild head motion while severely restricting larger motion. These observations are useful because they open the possibility that halo orthosis installation could be optimized to transfer mild spinal loads that support healing while blocking pathological loads.

Does routine pin re-torquing of patients wearing a halo-thoracic orthosis reduce the need for pin replacement?

The halo orthosis is a treatment option currently used in Australia for cervical spine immobilisation following trauma, fracture and post surgical stabilisation. In a previous study, the authors reported halo pin replacement to be a common complication. The aim of this study was to investigate the potential correlation between routine halo pin re-torquing and the incidence of pin replacement. A retrospective case series study was undertaken. A total of 258 charts were reviewed, with 170 patients included in the study. Patients were fitted with a Bremer HALO System with the initial application torque maintained by routine re-torquing throughout the duration of wear. A total of 680 pins (4 per patient) were inserted during the initial application of the halo orthoses, with only six pins replaced (0.88%) throughout the duration of the study. The findings from this study demonstrate a potential correlation between routinely re-torquing halo pins and decreasing the incidence of pin replacement. This case series study has identified a potential improvement in clinical management of patients wearing a halo-thoracic orthosis.

"From writing illegibly to composing fiction: The story of a blind man with 20/20 vision".

Illegible handwriting on the part of physicians and nurses in hospital and outpatient charts is often said to be the reason for the electronic medical record (EMR). The virtues of the EMR are extolled far and wide and various gimmicks are incorporated to facilitate charting. For example, templates can be utilized that go into great detail describing a normal examination. If the examination is not normal when the doctor sees the patient and uses the EMR “canned” note, then the doctor must change the template and enter positive the findings in the patient's history and physical examination. However, if the “standard” entry is not factual for the patient being seen at a particular time and goes uncorrected, then we may be left with absurdities and contradictions. For example, in a recent chart review, I read about a blind man with 20/20 vision. Even though the chief complaint for the office visit after craniotomy for a pituitary tumor was “blindness after surgery,” the note itself went on to document 20/20 vision in both the right and left eyes and a normal neuro eye examination for both eyes. In another chart review case, a patient who was treated in a halo orthosis for a cervical fracture was said to have a “supple” neck with “normal neck range of motion” while still in the halo during an outpatient encounter with his neurosurgeon. I have no doubt that neither of the physicians who made those entries were lying (making intentionally deceptive statements).[1] They told a story that could have been true but was not. I think we call that fiction or perhaps B.S. or balderdash as suggested by Frankfort.[2]

Cervical spine clearance in the traumatically injured patient: is multidetector CT scanning sufficient alone?

Clearance of the cervical spine in patients who have sustained trauma remains a contentious issue. Clinical examination alone is sufficient in neurologically intact patients without neck pain. Patients with neck pain or those with altered mental status or a depressed level of consciousness require further radiographic evaluation. However, no consensus exists as to the appropriate imaging modality. Some advocate multidetector CT (MDCT) scanning alone, but this has been criticized because MDCT is not sensitive in detecting ligamentous injuries that can often only be identified on MRI. Patients were identified retrospectively from a prospectively maintained database at a Level I trauma center. All patients admitted between January 2004 and June 2011 who had a cervical MDCT scan interpreted by a board-certified radiologist as being without evidence of acute traumatic injury and who also had a cervical MRI study obtained during the same hospital admission were included. Data collected included patient demographics, mechanism of injury, Glasgow Coma Scale score at the time of MRI, the indication for and findings on MRI, and the number, type, and indication for cervical spine procedures. A total of 1004 patients were reviewed, of whom 614 were male, with an overall mean age of 47 years. The indication for MRI was neck pain in 662 patients, altered mental status in 467, and neurological signs or symptoms in 157. The MRI studies were interpreted as normal in 645 patients, evidencing ligamentous injury alone in 125, and showing nonspecific degenerative changes in the remaining patients. Of the 125 patients with ligamentous injuries, 66 (52.8%) had documentation of clearance (29 clinical, 37 with flexion-extension radiographs). Another 32 patients were presumed to be self-cleared, bringing the follow-up rate to 82% (98 of 119). Five patients died prior to clearance, and 1 patient was transferred to another facility prior to clearance. Based on these data, the 95% confidence interval for the assertion that clinically irrelevant ligamentous injury in the face of normal MDCT is 97%-100%. No patient with ligamentous injury on MRI was documented to require a surgical procedure or halo orthosis for instability. Thirty-nine patients ultimately underwent cervical surgical procedures (29 anterior and 10 posterior; 5 delayed) for central cord syndrome (21), quadriparesis (9), or discogenic radicular pain (9). None had an unstable spine. In this study population, MRI did not add any additional information beyond MDCT in identifying unstable cervical spine injuries. Magnetic resonance imaging frequently detected ligamentous injuries, none of which were found to be unstable at the time of detection, during the course of admission, or on follow-up. Magnetic resonance imaging provided beneficial clinical information and guided surgical procedures in patients with neurological deficits or radicular pain. An MDCT study with sagittal and coronal reconstructions negative for acute injury in patients without an abnormal motor examination may be sufficient alone for clearance.

Occipitocervical fusion using a contoured rod and wire construct in children: a reappraisal of a vintage technique

Many methods to stabilize and fuse the craniocervical junction have been described. One of the early designs was a contoured (Luque) rod fixated with wires, the so-called Hartshill-Ransford loop. In this study, the authors report their 20-year experience with this surgical technique in children. The authors reviewed the medical records of patients 18 years of age or younger who underwent dorsal occipitocervical fusion procedures between March 1992 and March 2012 at Le Bonheur Children's Hospital using a contoured rod and wire construct. Data on basic patient characteristics, causes of instability, neurological function at presentation and at last follow-up, details of surgery, complications, and radiographic outcome were collected. Twenty patients (11 male) were identified, with a mean age of 5.5 years (range 1-18 years) and a median follow-up of 43.5 months. Fourteen patients had atlantooccipital dislocation, 2 patients had atlantoaxial fracture-dissociations, 2 had Down syndrome with occipitocervical and atlantoaxial instability, 1 had an epithelioid sarcoma from the clivus to C-2, and 1 had an anomalous atlas with resultant occipitocervical instability. Surgical stabilization extended from the occiput to C-1 in 3 patients, C-2 in 6, C-3 in 8, and to C-4 in 3. Bone morphogenetic protein was used in 2 patients. Two patients were placed in a halo orthosis; the rest were kept in a hard collar for 6-8 weeks. All patients were neurologically stable after surgery. One patient with a dural tear experienced wound dehiscence with CSF leakage and required reoperation. Eighteen patients went on to achieve fusion within 6 months of surgery; 1 patient was initially lost to follow-up, but recent imaging demonstrated a solid fusion. There were no early hardware or bone failures requiring hardware removal, but radiographs obtained 8 years after surgery showed that 1 patient had an asymptomatic fractured rod. There were no instances of symptomatic junctional degeneration, and no patient was found to have increasing lordosis over the fused segments. Five (31%) of the 16 trauma patients required a shunt for hydrocephalus. Despite the proliferation of screw-fixation techniques for craniocervical instability in children, the contoured rod-wire construct remains an effective, less expensive, and technically easier alternative that has been in use for almost 30 years. It confers immediate stability, and therefore most patients will not need to be placed in a halo device postoperatively. A secondary observation in our series was the high (30%) rate of hydrocephalus requiring a shunt in patients with traumatic instability.

Successful antibiotic treatment for subdural empyema and seizure due to methicillin-resistant Staphylococcus aureus as a complication of halo orthosis usage: a case report.

Halo orthosis is used for cervical spine fixation after spinal surgery or injury. Although superficial infection at pin sites occurs frequently, intracranial development of infection, including brain abscesses, is very rare. We experienced subdural empyema due to methicillin-resistant Staphylococcus aureus (MRSA) caused by intracranial penetration of halo pins. A 38-year-old woman with a 4-year history of rheumatoid arthritis experienced severe myelopathy due to atlanto-axial dislocation and vertical subluxation. Reduction and immobilization using a halo vest resulted in neurologic improvement; she later underwent occipital bone to C2 fusion using posterior instrumentation. Three months after halo orthosis fixation, she complained of a headache, experienced a generalized tonic-clonic seizure, and became unconscious for 10min. Computed tomography revealed pneumoencephalus, and Gd-enhanced magnetic resonance imaging revealed edema, enhancement of the overlying dura in the left partial lobe, and subdural and subarachnoidal empyema. Following removal of the halo vest, there was a purulent discharge from the left-posterior pin site. Culture of the discharge was positive for MRSA. The patient was treated with intravenous vancomycin for 2weeks, followed by cefozopran hydrochloride for 4weeks. Her symptoms improved, and additional surgery was not required. At latest follow-up, 10years after the seizure, she is neurologically stable without any recurrence of the infection.

Open reduction and internal fixation for angulated, unstable odontoid synchondrosis fractures in children: a safe alternative to halo fixation?

External orthosis is the accepted and historical management of odontoid synchondrosis fractures; however, this conservative therapy carries a significant complication and fracture nonunion rate among young children. The purpose of this study was to evaluate the authors' own experience in the context of the literature, to explore surgical fixation as a primary treatment for unstable fractures. The authors retrospectively reviewed 2 cases of unstable odontoid synchondrosis fractures treated at their institution; both showed radiographic progression of deformity and subsequently underwent an open surgical reduction and fusion. A literature review was conducted to compare the authors' management strategy with those in published data. External orthosis for treatment of odontoid synchondrosis fractures has a strong history of success. However, in the literature, patients treated with a halo orthosis had a 43.3% rate of complications and an 11.4% risk of nonunion. There are radiographic findings that suggest instability, such as severe angulation and displacement of the odontoid process. Both patients in the present report underwent successful fusion without complication, as documented on CT scans obtained 3 months after surgery. Given the high rate of fusion attained with conservative therapy, it is recommended for most synchondrosis fractures. However, there is a recognized subgroup of synchondrosis fractures with severe angulation (> 30°) and displacement suggestive of significant ligamentous injury. In these patients, surgical fixation may be a safe and efficacious alternative to halo orthosis as the primary treatment.

The Thickness of Skull at the Halo Pin Insertion Site

The thickness of 415 skulls of Thai population was measured at the areas where halo pins are placed. Analysis of skull thickness at the area of halo pin insertion site. Halo orthosis is a device used for providing stable fixation of instability of cervical spine injury. Although this device can be applied quickly and safely, complications do occur. While clinical experiences have informed us that cranial bone thickness varies with age. Coronal computerized tomography scans of 415 heads of patients who had no head injury, skull fracture, or craniofacial abnormalities were reviewed. All scans were performed with a Philips CX/Q. The patients' ages were between 15 days and 89 years. Measurements were taken directly from the computer console, using the measure mode function. These measurements were obtained in millimeters at the locations where halo pins would normally be placed. Statistical analyses within and between all age groups were performed using analysis of variance tests. The skull thickness increased with age at all sites measured. The average thickness of skull at the anterior midline varied from 5.62 mm (0-9 years) to 7.42 mm (80-89 years). The average thickness of the anterolateral was from 5.52 to 8.54 mm, and the average thickness of the posterolateral was from 5.59 to 8.86 mm. The thickness of skull at the halo pin insertion site gradually increases with age. Our study reveals that the thickness of skull reaches a steady peak in third to sixth decades. The thickness of skull at the anterior midline can be predicted by a simple linear regression equation: A = 7.302 + 0.014*age.

Occipitocervical instrumentation in the pediatric population using a custom loop construct: initial results and long-term follow-up experience

Rigid occipitocervical instrumentation for craniovertebral instability is gaining widespread acceptance for use in pediatric patients; however, most of the instrumentation has been modified from adult-sized hardware. The Wasatch loop system (formerly the Avery-Brockmeyer-Thiokol loop system) is a rigid occipitocervical fixation device designed specifically for use in children. It affixes to the occiput and incorporates either C1-2 transarticular screws or C-2 pars screws. It is preformed and is available in a variety of sizes. The authors describe their clinical experience and long-term follow-up experience with the first 22 patients. An institutional review board-approved retrospective review of medical records and radiographs was performed for patients who underwent occipitocervical fusion with the Wasatch loop. The mean patient age was 4.9 years (1.2-13 years), and the overall mean follow-up was 4 years (1.5-6.5 years). Six patients had posttraumatic instability, and 16 patients had congenital instability. Twelve patients underwent placement of bilateral C1-2 transarticular screws, 6 patients had placement of a combination of C1-2 transarticular and C-2 pars screws, and 4 patients had placement of bilateral C-2 pars screws. One patient required a halo orthosis; the others were treated postoperatively with a hard cervical collar. All patients had radiographic evidence of solid occipitocervical arthrodesis on last follow-up examination. The Wasatch loop system is a novel internal fixation device for children who have posttraumatic or congenital occipitocervical instability. Successful arthrodesis was achieved in all patients with minimal use of halo orthoses.

A case of pneumocephalus and brain injury associated with halo orthosis

A case of pneumocephalus and brain injury associated with halo orthosis

Case report of halo orthosis in early prevention of neck burns contracture

Case report of halo orthosis in early prevention of neck burns contracture

USE OF AXIAL AND SUBAXIAL TRANSLAMINAR SCREW FIXATION IN THE MANAGEMENT OF UPPER CERVICAL SPINAL INSTABILITY IN A SERIES OF 7 CHILDREN

The management of upper cervical spinal instability in children continues to represent a technical challenge. Traditionally, a number of wiring techniques followed by halo orthosis have been applied; however, they have been associated with a high rate of nonunion and poor tolerance for the halo. Alternatively, C1-C2 transarticular screws and C2 pars/pedicle screws allow more rigid fixation, but they are technically demanding and associated with vertebral artery injuries. Recently, C2 translaminar screws have been added to the armamentarium of the pediatric spine surgeon as a technically simple and biomechanically efficient method of fixation. However, subaxial translaminar screws have not been described in the pediatric population. We describe our experience with axial and subaxial translaminar screws in 7 pediatric patients. Seven pediatric patients with the diagnosis of upper cervical spinal instability required surgical fixation (age, 19 months-14 years; sex, 4 boys and 3 girls; follow-up, 4-21 months; etiology, trauma [3 patients], os odontoideum/os terminale [2 patients], hypoplastic dens [2 patients]). All patients underwent axial and/or subaxial translaminar screw insertion. Iliac crest bone graft was used for fusion in 4 patients; bone morphogenic protein and cancellous morselized allograft was used for fusion in 3 patients. A rigid cervical collar was applied for 12 weeks postoperatively in all cases. No intraoperative image guidance was used for insertion of the translaminar screws. All patients had a postoperative computed tomographic scan. Two patients underwent placement of bilateral crossing C2 translaminar screws. Two patients had subaxial translaminar screw placement at C3 and the upper thoracic spine, respectively. Hybrid constructs (a C2 translaminar screw combined with a C2 pars screw) were incorporated in 3 patients. No patients were found to have a breach of the ventral laminar cortex. All patients achieved solid fusion. One patient had a perioperative complication: prolonged dysphagia probably related to C1 lateral mass screw insertion rather than C2 translaminar screw placement. To our knowledge, this report represents the only series of pediatric patients treated with axial and subaxial translaminar screws. This series shows that axial and subaxial translaminar screw fixation is a viable option for upper cervical spinal fusion in children. The technique is safe and results in adequate fixation with high fusion rates and minimal complications.

Computed tomography morphometric analysis for axial and subaxial translaminar screw placement in the pediatric cervical spine

The management of upper cervical spinal instability in children continues to represent a technical challenge. Traditionally, a number of wiring techniques followed by halo orthosis have been applied; however, they have been associated with a high rate of nonunion and poor tolerance for the halo. Alternatively, C1-2 transarticular screws and C-2 pars/pedicle screws allow more rigid fixation, but their placement is technically demanding and associated with vertebral artery injuries. Recently, C-2 translaminar screws have been added to the armamentarium of the pediatric spine surgeon as a technically simple and biomechanically efficient means of fixation. However, the use of subaxial translaminar screws have not been described in the general pediatric population. There are no published data that describe the anatomical considerations and potential limitations of this technique in the pediatric population. The cervical vertebrae of 69 pediatric patients were studied on CT scans. Laminar height and thickness were measured. Statistical analysis was performed using unpaired Student t-tests (p<0.05) and linear regression analysis. The mean laminar heights at C-2, C-3, C-4, C-5, C-6, and C-7, respectively, were 9.76+/-2.22 mm, 8.22+/-2.24 mm, 8.09+/-2.38 mm, 8.51+/-2.34 mm, 9.30+/-2.54 mm, and 11.65+/-2.65 mm. Mean laminar thickness at C-2, C-3, C-4, C-5, C-6, and C-7, respectively, were 5.07+/-1.07 mm, 2.67+/-0.79 mm, 2.18+/-0.73 mm, 2.04+/-0.60 mm, 2.52 +/- 0.66 mm, and 3.84+/-0.96 mm. In 50.7% of C-2 laminae, the anatomy could accept at least 1 translaminar screw (laminar thickness>or=4 mm). Overall, the anatomy in 30.4% of patients younger than 16 years old could accept bilateral C-2 translaminar screws. However, the anatomy of the subaxial cervical spine only rarely could accept translaminar screws. This study establishes anatomical guidelines to allow for accurate and safe screw selection and insertion. Preoperative planning with thin-cut CT and sagittal reconstruction is essential for safe screw placement using this technique.

Management of brain abscesses associated with halo fixation

Halo orthoses are commonly used in the management of a variety of cervical spinal pathological conditions. Although placement of the cranial pins was initially believed to be safe with minimal complications, minor complications related to the cranial pins have the potential to create a setting for formation of cerebral abscesses. The risk of death due to cerebral abscesses has declined in the modern antibiotic era, but cerebral abscesses are associated with long-standing neurological morbidity that should not be considered negligible. Prevention by careful pin placement and hygiene and appropriate early management are crucial to prevent more serious complications. The authors report the case of a patient treated with a halo orthosis after incurring cervical spinal trauma who developed a cerebral abscess as a complication related to the cranial pins of the halo fixation device. They review the literature in an attempt to formulate a standardized treatment algorithm to prevent this disease process and to treat an abscess if it should form.