Cervical fixation in the pediatric patient: our experience

Autologous rib grafts for craniocervical junction surgery in children: a clinical application

OBJECTIVE

Autologous iliac bone is commonly used as a bone graft material to achieve solid fusion in craniocervical junction (CVJ) surgery. However, the developing iliac bone of children is less than ideal as a bone graft material. The matured rib bone of children presents a potential substitute material for iliac bone. The aim of this study was to evaluate the efficacy of autologous rib grafts for craniocervical junction surgery in children.

METHODS

The outcomes of 10 children with abnormalities of the craniocervical junction who underwent craniocervical junction surgery between January 2020 and December 2022 were retrospectively reviewed. All patients underwent posterior fusion and internal fixation surgery with autologous rib grafts. Pre- and post-operative images were obtained and clinical follow-ups were conducted to evaluate neurological function, pain level, donor site complications, and bone fusion rates.

RESULTS

All surgeries were successful. During the 8- to 24-month follow-up period, all patients achieved satisfactory clinical results. Computed tomography at 3-6 months confirmed successful bone fusion and regeneration of the rib defect in all patients with no neurological or donor site complications.

CONCLUSION

Autologous rib bone is a safe and effective material for bone grafting in craniocervical junction fusion surgery for children that can reduce the risks of donor site complications and increase the amount of bone graft, thereby achieving a higher bone fusion rate.

Feasibility of Anterior Fixation with Single Screw for Odontoid Fractures in Pediatrics: A Computed Tomographic Study

OBJECTIVE

Although it is an effective fixation technique for an unstable odontoid, anterior fixation remains challenging in pediatric populations. Our study measures the anatomical parameters of the odontoid to identify the feasibility of anterior fixation with a single screw for children.

METHODS

We retrospectively collected data from 112 normal male and female children (aged between 2 and 18) in our institute from January 1, 2022 to December 31, 2022. Subjects were divided into a youth group (2-6 years old), a juvenile group (7-12 years old), and an adolescent group (13-18 years old). Sagittal and coronal computed tomography images of the upper cervical spine were used to measure the screw length, angle, and inner and outer diameters of the odontoid. One-way analysis of variance with the Tukey test was used to analyze the parameters among the groups, while the t-test was used to analyze gender differences. Correlations between parameters and age were assessed using Pearson's test.

RESULTS

There were significant differences between male and female subjects in screw length and inner and outer diameters (of both sagittal and coronal views) but not in screw angle. The narrowest diameter of the odontoid was 4.0 ± 1.5 mm in the youth group, 5.5 ± 1.5 mm in the juvenile group, and 5.6 ± 1.1 mm in the adolescent group, respectively. There were significant differences among the three groups in screw length (p < 0.0001). The screw angle of the adolescent group was significantly smaller than that of the youth and juvenile groups. More than 90% of children aged 7-18 years old had an odontoid diameter greater than 4 mm, while only half of the youth group had an odontoid with diameter >4 mm. Screw length and inner and outer diameters in lateral view were positively correlated with age, and screw angle was negatively correlated with age.

CONCLUSION

It is feasible to insert a standard single screw (Φ 3.5 mm) into the odontoid of children aged 7-18 years old but not those aged 2-6 years old. How the anatomical parameters of the odontoid change with age, especially the narrowest diameters, is worthy of attention.

Complications of occipitocervical fixation: retrospective review of 128 patients with 5-year mean follow-up

PURPOSE

Occipitocervical fusion is necessary for many pathologies of the craniocervical junction. The anatomy of the region is unique, and fusion can cause significant morbidity. This retrospective review aims to investigate the complication rates and outcomes of occipitocervical fixation.

MATERIAL AND METHODS

This is a retrospective review of 128 patients with occipitocervical fixation operated between 1994 and 2020. The average follow-up is 63 months.

RESULTS

The indications of occipitocervical fixation were basilar invagination (53 patients; 41.4%), trauma (25 patients; 19.5%), tumor (23 patients; 18%), instability due to rheumatoid arthritis (13 patients; 10.2%), cervical deformity (7 patients; 5.5%) and os odontoideum (7 patients; 5.5%). There were six early postoperative (1st month) deaths. We observed complications in 67 patients (52%). Most common complication was implant-related (32%), followed by wound problems (23.4%), systemic and other complications (11.7%), neurologic complications (6.2%). Implants are removed in 31 patients (24%) for different reasons: deep wound infection (7), local pain and restriction of head movements (21), respiratory distress and swallowing problems (2), screw fracture and local pain (1).

CONCLUSIONS

Occipitocervical fixation has quite large number of complications and significantly restricts head movements. With the advent of our biomechanical concepts, indications should be limited, and shorter cervical fixations should be preferred.

LEVEL OF EVIDENCE

Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Posterior fixation for paediatric and adolescent unstable hangman's fracture: evolution to C1 sparing techniques

PURPOSE

The aim was to study surgical outcomes in hangman's fractures in paediatric and adolescent patients and to demonstrate evolution in posterior surgery from C1-C2-C3 fusion to C1 sparing techniques.

METHODS

Patients (aged ≤ 18 years) operated at a tertiary level centre between September 2011 to February 2018 with more than 1 year of follow-up were included. Neurological status, type of fracture, operating time, blood loss, follow-up, and complications were assessed.

RESULTS

Nine patients were included, with mean age mean of 16.45 years, with a mean follow-up of 42.78 months. Six patients having neurological deficit showed improvement. Two patients, one having undergone C1-C3 lateral mass screw rod fixation (LMSF) and other had C2 pedicle screw with C3 LMSF, developed kyphosis for which fixation was further extended caudally. One patient with an old hangman's fracture with reabsorbed axis pedicle underwent C2 body screw along with C3-C4 pedicle screw rod fixation and C2 pedicle reconstruction. All patients showed evidence of postoperative fusion.

CONCLUSION

Hangman's fractures in young patients can be successfully managed via posterior fixation. In our centre, we have evolved in the direction of motion preservation at C1 C2 joint, along with 3 column stable fixation of the C2 pedicle. C2 pedicle reformation has allowed motion preserving surgery in complex fracture types. Extension of construct till C4 in selected cases is important to prevent postoperative kyphosis.

Anterior Odontoid Screw Fixation for Pediatric and Adolescent Odontoid Fractures: Single-Center Experience Over a Decade

OBJECTIVE

Management of pediatric odontoid fractures is tricky and controversial. This study will enrich world literature with intricacies of anterior odontoid screw (OS) fixation in the pediatric population learned over the last decade.

METHODS

In this retrospective study, all patients with pediatric odontoid fracture who underwent anterior odontoid screw fixation from January 2010 to December 2019 were included and evaluated for surgical outcome.

RESULTS

Thirteen patients were included in this study (mean age, 15 years; range, 6-18 years; male/female, 11:2; type II, 10; type IIA, 1; type III, 2). Common causes of injury were motor vehicle accidents (61.5%) followed by fall from height (38.5%) and all were acute fractures (2-30 days). Five patients had neurologic deficits. Accurate placement of screw was achieved in 92.3% of patients, including all 9 patients who used intraoperative O-arm. K wire migration during bicortical drilling resulted in neurovascular injury, with 1 mortality (7.7%). The remaining 12 patients were available for follow-up (mean, 36 months; range, 20-72 months) and all had preservation of neck movements. Successful OS fixation was achieved in 84.6% of patients, including 1 patient (7.7%) who had a fibrous union. One patient (8.3%) had nonunion because of migration of the screw head in the C2 body.

CONCLUSIONS

Anterior odontoid screw fixation in the pediatric population provides good functional outcomes with instant fixation by direct osteosynthesis. However, the surgeon should be meticulous in the surgical approach and should achieve a lag effect. The surgeon should stop after engaging the outer cortex of the odontoid peg with K wire to avoid cranial migration. Intraoperative O-arm guidance is useful.

Occipital Plate Fixation in the Pediatric Population

BACKGROUND

Occipital plate fixation has been shown to improve outcomes in cervical spine fusion. There is a paucity of literature describing occipital plate fixation, especially in the pediatric population. The authors reviewed a case series of 34 patients at a pediatric hospital who underwent cervical spine fusion with occipital plate fixation between 2003 and 2016. This study describes how occipital plates aid the cervical spine union in a case series of diverse, complex pediatric patients.

METHODS

Our orthopaedic database at our institution was queried for patients undergoing an instrumented cervical spine procedure between 2003 and 2016. Medical records were used to collect diagnoses, fusion levels, surgical technique, and length of hospitalization, neurophysiological monitoring, complications, and revision procedures.

RESULTS

Thirty-four patients met the inclusion criteria. The mean age was 10.9 years (range, 3-21 y). Indications for surgery included cervical instability, basilar invagination, and os odontoideum. These indications were often secondary to a variety of diagnoses, including trisomy 21, Klippel-Feil syndrome, and rheumatoid arthritis. The mean length of hospitalization was 10 days (range, 2 to 80 d). There were no cases of intraoperative dural leak, venous sinus bleeding from occipital screw placement, or implant-related complications. Postoperative complications included 2 cases of nonunion. Eight patients (24%) had follow-up surgery, only 3 (9%) of which were instrumentation revisions. Both patients with nonunion had repeat occipitocervical fixation procedures and achieved union with revision.

CONCLUSIONS

Occipital plate fixation was successful for pediatric cervical spine fusion in this diverse cohort. The only procedure-related complication demonstrated was delayed union or nonunion and implant loosening (4/34, 12%) and there were no plate-related complications. This novel case series shows that occipital plate fixation is safe and effective for pediatric patients with complex diagnoses.

LEVEL OF EVIDENCE

Level IV-case series.

Craniovertebral junction instability in Larsen syndrome: An institutional series and review of literature

Objective

Larsen syndrome (LS) is characterized by osteo-chondrodysplasia, multiple joint dislocations, and craniofacial abnormalities. Symptomatic myelopathy is attributed to C1-C2 instability and sub-axial cervical kyphosis. In this article, we have analyzed the surgical outcome after posterior fixation in LS with craniovertebral junction instability.

Methods

Ten symptomatic pediatric patients, operated between 2011 and 2019, were included, and the clinical outcome was assessed by Nurick grade, neurological improvement, and complications. The requirement of anti-spasticity drugs, the degree of bony fusion, and restriction of neck movement were also noted. At last follow-up, patient satisfaction score (PSS) and back to school status were studied. We also reviewed the literature and categorized two types of presentation of reported LS patients and discussed the pattern of disease progression among both.

Results

Ten patients, age range 1.5-16 years, underwent 12 surgeries (6 C1-C2 fixation, 4 long-segment posterior cervical fixation, and 2 trans-oral decompressions as the second stage); the mean follow-up was 23 (range, 6-86 months). All the ten patients in our study had the characteristic "dish-" like face and nine patients had acral anomalies. The median Nurick grade improved from preoperative (median = 4) to follow-up (median = 3). The requirement of anti-spasticity drugs decreased in seven patients and the neck-pain improved in nine patients. The median satisfaction at follow-up was good (median PSS = 2); five patients were going back to school.

Conclusion

Craniovertebral junction instability in LS is rare and surgically challenging. Early posterior fixation showed a promising outcome with a halt in the disease progression.

Narcotrend-guided intraoperative care of a Trisomy 21 paediatric patient who underwent occipitocervical fusion

A 9-year-old female with Trisomy 21 with complex craniovertebral instability causing severe cervicomedullary compression underwent occipitocervical fusion. This paper will discuss the anaesthetic management and highlight the use of the Narcotrend monitor not only as a depth of consciousness monitor but more importantly as a tool to detect surgery-induced cerebral hypoperfusion by monitoring the right and left cerebral hemispheres independently and simultaneously.

Craniovertebral junction fixation in children less than 5 years

PURPOSE

Whilst rigid fixation for craniovertebral instability is the gold standard, in very young, small children conventional management may have to be modified. We present a single-centre experience of craniocervical fixation in children under 5 years.

METHODS

A retrospective review of cases that had undergone atlantoaxial (AA) or occipitocervical (OC) fixation aged under 5 years. Fusion was assessed using computerised tomography or flexion extension X-rays.

RESULTS

Twenty-six children (median age 2.3, range 0.8-4.9 years, 19 under the age of 3) underwent OC (n = 19) or AA (n = 7) fusion between 1999 and 2016. Pathology comprised 17 congenital, five trauma, two tumour and two post-infection cases. Twenty-one patients underwent sublaminar cable fixation with calvarial, autologous bone graft and halo-body orthosis immobilisation. An occipital plate and rods to sublaminar wire construct were used in four cases. A rigid instrumented fixation with occipital plate and C2 pedicle screws was utilised in one case. Follow-up was for a median of 2.8 years (range 0.03-16.3 years). Initial fusion rate was 91%, reaching 100% following two re-operations. Ninety-two per cent of patients were neurologically stable or improved following surgery. Twenty-one patients had a good overall outcome. Two patients had post-operative neurological deteriorations, and four died due to non-procedure related causes. Pin site morbidity secondary to halo use occurred in five cases.

CONCLUSION

High fusion rates with good outcomes are achievable using semi-rigid fixation in the under 5-year-olds. Full thickness, autologous calvarial bone graft secured with wire cables and halo external orthosis offers a safe and effective alternative technique when traditional screw instrumentation is not feasible. These slides can be retrieved under Electronic Supplementary Material.

Nonmetallic posterior monosegmental cervical fusion of a dislocated C6/7 fracture in a 4-year-old girl : A case report

PURPOSE

Pediatric cervical spine injuries constitute approximately 1-2% of all pediatric trauma cases. Usually pediatric vertebral injuries appear as stable A type fractures, whereas B and C type injuries are relatively uncommon. In contrast to adults, the appropriate treatment strategy in children is still controversial and places spine surgeons in complex situations. This article reports the case of a 4-year-old girl with an unstable B type injury at the C6/7 level (AOSpine C6-7: B2 [F4 BL, C7:A1]) with bilateral locked fractures of the facet joints after falling down a flight of stairs.

PATIENT AND METHODS

Magnetic resonance imaging (MRI) and computed tomography (CT) were initially performed. The 4‑year-old girl was treated under intraoperative neurophysiological monitoring via open reduction after partial resection of both C7 upper articular processes and nonmetallic monosegmental posterior interlaminar fusion (FiberWire®) at the C6/7 level with temporary immobilization in a halo brace.

RESULTS

Clinical and radiological follow-up was carried out after 9 months. The patient suffered no pain or neurological deficits. Plain radiographs revealed a correct cervical alignment with anatomical correction of the initial dislocation.

CONCLUSION

The treatment of highly unstable pediatric B type injuries of the lower cervical spine via open reduction and nonmetallic monosegmental posterior interlaminar fusion results in good clinical and radiological outcomes. A temporary immobilization in a halo brace provides stability until osseous fusion occurs.

Anterior cervical corpectomy and fusion in a 7-year-old boy: a case report

Bicycle mishap, a common and ordinary event occurring in children, can have devastating consequences associated with cervical spine injury. Furthermore, either diagnosis or surgical management of cervical spine injury in children is a challenging issue. This research report a challenging case of an anterior cervical corpectomy and fusion with plating in a 7-year-old boy due to cervical spine instability with spinal cord compression after a bicycle mishap. After 20 months of the primary surgery, the titanium-based cervical plate was removed by a second surgery to allow the growth of the cervical spine.

Autogenic Rib Graft for Atlantoaxial and Occipitocervical Fixation in Pediatric Patients

Study Design

Retrospective case series.

Purpose

To evaluate surgical outcomes and effectiveness of an autogenic rib graft for upper cervical fixation in pediatric patients.

Overview of Literature

Autogenic bone grafts have long been considered the ‘gold standard’ bone source for posterior cervical fusion in pediatric patients. However, there are some unsolved problems associated with donor-site morbidity and amount of bone grafting.

Methods

We studied five consecutive pediatric patients who underwent atlantoaxial fixation or occipitocervical fixation (OCF) using an autogenic rib graft with at least 2 years of follow-up (mean age, 9.8 years; mean follow-up period, 73.0 months). Two patients underwent OCF without screw-rod constructs and three patients with screw-rod constructs. Autogenic rib grafts were used in all patients. We evaluated the surgical outcomes including radiographic parameter, bony union, and perioperative complications.

Results

The atlantoaxial interval (ADI) was corrected from 11.6 to 6.0 mm, and the C1–2 angle was corrected −14.8° to 7.8°. The C2–7 angle was reduced from 31° to 9° spontaneously. Two patients with OCF required revision surgery due to loss of correction. Patients did not experience any complication associated with the donor sites (rib bone grafts). Six months postoperation X-rays clearly showed regeneration of the rib at the donor sites. Bony fusion was achieved in all patients; however, bony fusion occurred more slowly in patients without screw-rod constructs compared with patients with screw-rod constructs. Bone regeneration of the rib was observed in all patients with no complications at the donor site.

Conclusions

Autogenic rib grafts have advantages of potential bone regeneration, high fusion rate, and low donor-site morbidity. In addition, a screw-rod construct provides better bony fusion in pediatric patients with OCF and atlantoaxial fixation.

Identifying Factors Predictive of Atlantoaxial Fusion Failure in Pediatric Patients: Lessons Learned From a Retrospective Pediatric Craniocervical Society Study

STUDY DESIGN

Multicenter retrospective cohort study with multivariate analysis.

OBJECTIVE

To determine factors predictive of posterior atlantoaxial fusion failure in pediatric patients.

SUMMARY OF BACKGROUND DATA

Fusion rates for pediatric posterior atlantoaxial arthrodesis have been reported to be high in single-center studies; however, factors predictive of surgical non-union have not been identified by a multicenter study.

METHODS

Clinical and surgical details for all patients who underwent posterior atlantoaxial fusion at seven pediatric spine centers from 1995 to 2014 were retrospectively recorded. The primary outcome was surgical failure, defined as either instrumentation failure or fusion failure seen on either plain x-ray or computed tomography scan. Multiple logistic regression analysis was undertaken to identify clinical and technical factors predictive of surgical failure.

RESULTS

One hundred thirty-one patients met the inclusion criteria and were included in the analysis. Successful fusion was seen in 117 (89%) of the patients. Of the 14 (11%) patients with failed fusion, the cause was instrumentation failure in 3 patients (2%) and graft failure in 11 (8%). Multivariate analysis identified Down syndrome as the single factor predictive of fusion failure (odds ratio 14.6, 95% confidence interval [3.7-64.0]).

CONCLUSION

This retrospective analysis of a multicenter cohort demonstrates that although posterior pediatric atlantoaxial fusion success rates are generally high, Down syndrome is a risk factor that significantly predicts the possibility of surgical failure.

LEVEL OF EVIDENCE

3.

Instrumented cervical spinal fusions in children: indications and outcomes

PURPOSE

To report indications, outcomes and complications of instrumented cervical spinal fusion in a consecutive series of children at major university hospitals.

METHODS

A retrospective, single surgeon series identified 35 consecutive children with a mean follow-up (FU) of 2.5 years undergoing instrumented cervical spinal fusion between 2005 and 2015.

RESULTS

The main indications were skeletal dysplasia and trauma associated cervical instability. Surgical complications were observed in 12 (34%) patients with multiple complications in four (11%). Four (11%) children required at least one revision surgery, three for nonunion and one for graft dislodgement. All were fused at FU. Surgical complications were more common in children undergoing occipitocervical (OC) fusion than in those avoiding fusion of the OC junction (60% versus 24%) (p = 0.043). Complications were found significantly more in children operated on under the age of ten years than above (50% versus 18%) (p = 0.004). The risk of complications was not dependent on the indications for surgery (skeletal dysplasia versus trauma) (p = 0.177).

CONCLUSION

Skeletal dysplasia associated cervical instability and cervical spine injuries represented the most common indications for instrumented cervical spinal fusion in children. Complications were observed in one-third of these children and 11% required revision surgery for complications. OC spinal fusion and spinal fusion before the age of ten years are associated with higher risk of surgical complications and increased mortality than non-OC fusions and cervical spinal fusions at an older age. We urge surgeons to employ caution to the patient, timing and procedure selection when treating paediatric cervical spine.

Traumatic atlanto-occipital dislocation in children-a case-based update on clinical characteristics, management and outcome

BACKGROUND

Atlanto-occipital dislocation (AOD) is a rare but severe sequela of high energy trauma. Children are at increased risk, due to their immature spine and biomechanical characteristics.

LITERATURE REVIEW

The prevailing mechanism of injury is motor vehicle collision as passenger. AOD commonly presents with cardiorespiratory arrest, spinal cord injury or cranial nerve deficits. Concomitant injuries, such as traumatic brain injury, are frequently encountered. Diagnosis is made on CT and MRI imaging. Posterior internal fixation is the recommended treatment. Thirty-four percent of patients die, 41 % survive with deficits and 25 % have a complete neurological recovery. Initial symptoms, GCS score and degree of spinal cord injury appear to be predictors of outcome.

ILLUSTRATIVE CASE

We report the case of a 9-year-old boy, who presented in extremis with cardiac arrest after a motor vehicle collision. Upon successful resuscitation, diagnostic imaging showed AOD and a Chiari I malformation. An occiput-C2 posterior instrumented fusion was performed. The patient subsequently received intensive rehabilitation and recovered to independent ambulation, with a persistent, asymptomatic Chiari I malformation.

CONCLUSION

This case highlights the potential for positive outcome in paediatric AOD, despite the presence of strong predictors of poor or fatal outcome at presentation.

Allograft versus autograft for pediatric posterior cervical and occipito-cervical fusion: a systematic review of factors affecting fusion rates

OBJECT Fusion rates are high for children undergoing posterior cervical fusion (PCF) and occipito-cervical fusion (OCF). Autologous bone has been widely used as the graft material of choice, despite the risk of donor-site morbidity associated with harvesting the bone, possibly because very low fusion rates were reported with posterior allograft cervical fusions in children several decades ago. Higher overall fusion rates using allograft in adults, associated with improvements in internal fixation techniques and the availability of osteoinductive substances such as bone morphogenetic protein (BMP), have led to heightened enthusiasm for the use of bank bone during pediatric PCF. A systematic review was performed to study factors associated with successful bone fusion, including the type of bone graft used. METHODS The authors performed a comprehensive PubMed search of English-language articles pertaining to PCF and OCF in patients less than 18 years old. Of the 561 abstracts selected, 148 articles were reviewed, resulting in 60 articles that had sufficient detail to be included in the analysis. A meta-regression analysis was performed to determine if and how age, fusion technique, levels fused, fusion substrate, BMP use, postoperative bracing, and radiographic fusion criteria were related to the pooled prevalence estimates. A systematic review of the literature was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. RESULTS A total of 604 patients met the specific inclusion and exclusion criteria. The overall fusion rate was 93%, with a mean age of 9.3 years and mean follow-up of 38.7 months. A total of 539 patients had fusion with autograft (94% fusion rate) and 65 patients with allograft (80% fusion rate). Multivariate meta-regression analysis showed that higher fusion rates were associated with OCF compared with fusions that excluded the occiput (p < 0.001), with the use of autograft instead of allograft (p < 0.001), and with the use of CT to define fusion instead of plain radiography alone. The type of internal fixation, the use of BMP, patient age, and the duration of follow-up were not found to be associated with fusion rates in the multivariate analysis. CONCLUSIONS Fusion rates for PCF are high, with higher rates of fusion seen when autograft is used as the bone substrate and when the occiput is included in the fusion construct. Further study of the use of allograft as a viable alternative to autograft bone fusion is warranted because limited data are available regarding the use of allograft in combination with more rigid internal fixation techniques and osteoinductive substances, both of which may enhance fusion rates with allograft.

Anterior Reconstruction of C2-C3 Bodies in a 6-Year-Old Patient with a Huge Osteoblastoma: A Novel Technique

Study Design Case report. Objective We report the youngest child diagnosed with upper cervical osteoblastoma and the first case operated on with our novel surgical approach. Methods Our patient underwent a two-stage surgery. During the first operation via a posterior approach, a subtotal resection of a C2 bony mass was performed. C3 was also subtotally resected due to tumor extension. Posterior fixation of C1-C5 was performed by C1 sublaminar hooks and C4 and C5 lateral mass screws. Ten days later, a total resection of the residual bony mass was performed through an anterior approach (between the sternocleidomastoid muscle and carotid sheath). Reconstruction of C1-C3 was performed with C1 anterior sublaminar wiring and an expandable titanium cage. Results Successful reconstruction of C2-C3 vertebral bodies was achieved. At 2-year follow-up, the child was symptom-free. Imaging studies revealed no recurrence of tumor or instability. Conclusion A novel technique for reconstruction of C2-C3 vertebral bodies is demonstrated for the youngest case (a 6-year-old boy) of osteoblastoma in the literature. We recommend this approach for cervical spine reconstruction in patients who have an intact C1 arc and resected lower bodies.

Congenital cervical kyphosis in two young sighthounds

INTRODUCTION

Cervical vertebral (C) malformation is rarely reported in large breed dogs. Congenital cervical kyphosis (CCK) may result from defects of vertebral segmentation, failure of formation or both. This report describes two cases of C3-C4 CCK in young sighthounds, treated surgically.

CASE DESCRIPTION

An 18-month-old female Deerhound and a six-week-old female Borzoi dog were presented because of the complaints of reluctance to exercise and signs of of neck pain. Both dogs were neurologically normal. Diagnostic imaging revealed C3-C4 deformity, moderate kyphosis, and spinal canal stenosis associated with chronic spinal cord pressure atrophy. Both dogs underwent surgical treatment.

RESULTS

A staged two-step surgery starting with dorsal decompression was elected in the Deerhound. After the first surgical procedure, the dog developed focal myelomalacia and phrenic nerve paralysis and was euthanatized. A ventral distraction-fusion technique with two locking plates was performed in the Borzoi. This patient recovered uneventfully and long-term follow-up computed tomography revealed complete spondylodesis.

CLINICAL SIGNIFICANCE

Until now, CCK has only been described in sighthounds. Congenital cervical kyphosis might be considered a differential diagnosis in these breeds that are presented with signs of cervical pain. Ventral realignment-fusion and bone grafting may be considered for surgical treatment, although the earliest age at which this procedure can and should be performed remains unclear.

A new technique for stabilization of injuries at C2-C3 in young children

BACKGROUND

Reported surgical treatment for injuries and instabilities of the paediatric cervical spine most commonly involves posterior fusion with internal fixation, usually posterior wiring.

PURPOSE

To present a new simple technique of stabilization without fusion of the upper cervical spine of young children.

STUDY DESIGN

A technical report.

METHODS

Detailed description of the surgical procedure carried out for stabilizing an unstable flexion-distraction injury in a 23 month-old toddler, with severe head injury and pneumothorax is presented.

RESULTS

A rare unstable flexion-distraction injury in the upper cervical spine of a toddler was successfully treated with a posterior Number 2 Vicryl (polyglactin 910) suture fixation, with good healing of the ligaments and endplates, without fusion. Preservation of motion was achieved without obvious instability at 63 months post-surgery.

CONCLUSIONS

In selected cases of cervical spine injuries in the young paediatric population, a limited approach to the injured spinal segments and simple stabilization using suitable degradable sutures, can provide sufficient stability until healing occurs.

ADVANTAGES

fusion is avoided, growth disturbances are prevented and spinal motion maintained.

The use of inside-outside screws for occipitocervical fusion in pediatric patients

OBJECT

The authors describe the use of inside-outside occipital screws in 21 children with occipitocervical instability requiring occipitocervical fusion.

METHODS

The ages of the patients were from 2 to 15 years, and patients presented with a variety of causes of occipitocervical instability, including congenital disorders, posttraumatic instability, idiopathic degeneration, and postoperative instability. Surgeries frequently included foramen magnum decompression, duraplasty, and laminectomy, but all patients required occipitocervical instrumentation and arthrodesis. Postoperative orthosis included the use of either a cervical collar or halo device. In all but one case, patients were followed postoperatively for at least 12 months.

RESULTS

The mean age of patients was 9.93 years. Inside-outside screws were used in all reported cases. Rib autograft was used in all patients. In addition, demineralized bone matrix was used in 2 cases, and bone morphogenetic protein was used in 2 patients. Two patients required halo placement, and the other 19 were placed in cervical collars. The average time postoperative orthotics were used was 2.82 months. Arthrodesis was determined radiographically and was noted in all patients. No operative complications were noted; however, postoperative complications included 1 wound infection, 2 cases of hardware loosening, and the need for tracheostomy in 2 patients.

CONCLUSIONS

Inside-outside screws were found to be a useful component of occipitocervical instrumentation in pediatric patients ranging from 2 to 15 years of age. Arthrodesis was demonstrated in all cases.

Internal stabilization of a flexion-distraction injury of the upper cervical spine of a toddler: a new technique and literature review

STUDY DESIGN

A case report and literature review.

OBJECTIVE

To present a new and simple technique of fixation without fusion of a rare unstable Salter-Harris type I injury in the upper cervical spine of a 23-month-old toddler.

SUMMARY OF BACKGROUND DATA

Surgical treatment of unstable pediatric cervical spine injuries most commonly involves posterior fusion with internal fixation, usually posterior wiring.

METHODS

Detailed description of the surgical procedure carried out for fixating an unstable flexion-distraction injury in a 23-month-old toddler, with severe head injury and pneumothorax, is presented.

RESULTS

A rare unstable flexion-distraction injury in the upper cervical spine of a toddler was successfully treated with a posterior Number 2 Vicryl (polyglactin 910; ETHICON Division of Johnson & Johnson) suture fixation, with good healing of the ligaments and end plates, without fusion. Preservation of motion was achieved without obvious instability at 28 months postsurgery.

CONCLUSION

In selected cases of cervical spine injuries in the young pediatric population, simple stabilization of the spine using degradable Number 2 Vicryl (polyglactin 910) sutures with minimal exposure can provide sufficient stability until healing occurs. Advantages are that fusion is avoided and motion preserved.

Review of cervical spine anomalies in genetic syndromes

STUDY DESIGN

Focused review of the literature.

OBJECTIVE

Assist spine specialists in diagnosis and treatment of cervical spine anomalies found in selected genetic syndromes.

SUMMARY OF BACKGROUND DATA

Cervical spine instability and/or stenosis are potentially debilitating problems in many genetic syndromes. These problems can be overlooked among the other systemic issues more familiar to clinicians and radiologists evaluating these syndromes. It is imperative that spine specialists understand the relevant issues associated with these particular syndromes.

METHODS

The literature was reviewed for cervical spine issues in 10 specific syndromes. The information is presented in the following order: First, the identification and treatment of midcervical kyphosis in Larsen syndrome and diastrophic dysplasia (DD). Next, the upper cervical abnormalities seen in Down syndrome, 22q11.2 Deletion syndrome, pseudoachondroplasia, Morquio syndrome, Goldenhar syndrome, spondyloepiphyseal dysplasia congenita, and Kniest dysplasia. Finally, the chin-on-chest deformity of fibrodysplasia ossificans progressiva.

RESULTS

Midcervical kyphosis in patients with Larsen syndrome and DD needs to be evaluated and imaged often to track deformity progression. Upper cervical spine instability in Down syndrome is most commonly caused by ligamentous laxity at C1 to C2 and occiput-C1 levels. Nearly 100% of patients with 22q11.2 deletion syndrome have cervical spine abnormalities, but few are symptomatic. Patients with pseudoachondroplasia and Morquio syndrome have C1 to C2 instability related to odontoid dysplasia (hypoplasia and os odontoideum). Morquio patients also have soft tissue glycosaminoglycan deposits, which cause stenosis and lead to myelopathy. Severely affected patients with spondyloepiphyseal dysplasia congenita are at high risk of myelopathy because of atlantoaxial instability in addition to underlying stenosis. Kniest syndrome is associated with atlantoaxial instability. Cervical spine anomalies in Goldenhar syndrome are varied and can be severe. Fibrodysplasia ossificans progressiva features severe, deforming heterotopic ossification that can become life-threatening.

CONCLUSION

It is important to be vigilant in the diagnosis and treatment of cervical spine anomalies in patients with genetic syndromes.

Analysis of the treatment of 576 patients with congenital craniovertebral junction malformations

We aim to report our experience treating craniovertebral junction malformations (CVJM) and to investigate the management of this uncommon condition. Between 2000 and 2009, 629 patients with CVJM underwent surgery in our department. Fifty-three patients were lost to follow-up; therefore 576 patients completed follow-up, for an average period of 3 years and 2 months. All patients were diagnosed on the basis of clinical presentation and imaging features, and we found that anomalies of the occipitocervical junction manifested as four major types. Different microsurgical treatments were carried out in these patients according to disease type, and the effectiveness of individualised treatments was analysed. Categorizing patients with CVJM into these four types to simplify this somewhat unclear area could provide insight into the pathogenesis of the anomaly and a basis for rational surgical treatment.

Unique features of pediatric spinal cord injury

STUDY DESIGN

Systematic review.

OBJECTIVE

The objective of this systematic review was to identify the unique features associated with pediatric spinal cord injury (SCI) with the intention of determining the most effective spinal stabilization methods and identifying the optimum treatment for post-traumatic spinal deformity in pediatric patients with a SCI.

SUMMARY OF BACKGROUND DATA

Spinal injuries occur in 1.99/100,000 children, 10% are under 15 years, 60% to 80% occur in the cervical spine, and 5.4% to 34% in the thoracolumbar spine. The most frequent incident of spinal injury (50%-56%) occurs during motor vehicle accidents.

METHODS

A systematic review of the English language literature explored articles published between 1950 and 2009. Electronic databases (Medline and Embase) and reference lists of key articles were searched to identify unique features of pediatric SCI based on 2 questions: (1) "What is the most effective means to achieve spinal stabilization in pediatric patients with a SCI?" and (2) "What is the most effective treatment of post-traumatic spinal deformities in pediatric patients with a SCI?" Three Spinal Trauma Study Group faculty members assessed the level of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria and disagreements were resolved by a modified Delphi consensus.

RESULTS

No Level 1 or 2 evidence articles were discovered. Question 1 was addressed by 417 abstracts; from those 15 were selected for inclusion. This literature proved to be controversial, mostly focused on the adult population, pediatric series were retrospective, and most treatments were based on adult experience. The evidence supporting stabilization of the spine in the pediatric SCI population is very low for both the cervical and thoracic spinal regions. Question 2 was discussed in 517 abstracts; 8 relevant articles were selected. The principal key points, regarding the most effective treatment of post-traumatic spinal deformity in the pediatric SCI patients, suggest that the deformity should be prevented before the age of 10 to 12 years, younger SCI patients are unfavorable, nearly 100% of patients with SCI will develop a deformity, and brace treatment is generally recommended. Current evidence in support of brace use is very low.

CONCLUSION

Despite the lack of well-designed prospective studies to establish the efficacy of instrumentation in these cases, there remains very low evidence that supports the use of instrumentation in unstable pediatric spines to prevent neurologic injury and maintain spinal alignment. The very low evidence of benefits from early bracing clearly outweighs the risks and complications associated with its use. Close monitoring should be initiated early so as to delay surgical correction as late as possible. There is very low evidence to support the use of surgery for the treatment of deformity triggered by a SCI. There may be evidence suggesting that the correction techniques used for neuromuscular deformities are useful for SCI patients. In conclusion, there is a strong recommendation for the use of instrumentation in the unstable pediatric spinal injured population, and there is a strong recommendation for traditional neuromuscular spinal deformity treatment techniques to be adopted as a treatment of progressive spinal deformities after a neurologic injury.