Occipital condyle to cervical spine fixation in the pediatric population

Abstract

<jats:p>Fixation at the craniovertebral junction (CVJ) is necessary in a variety of pediatric clinical scenarios. Traditionally an occipital bone to cervical fusion is preformed, which requires a large amount of hardware to be placed on the occiput of a child. If a patient has previously undergone a posterior fossa decompression or requires a decompression at the time of the fusion procedure, it can be difficult to anchor a plate to the occipital bone. The authors propose a technique that can be used when faced with this difficult challenge by using the occipital condyle as a point of fixation for the construct. Adult cadaveric and a limited number of case studies have been published using occipital condyle (C-0) fixation. This work was adapted for the pediatric population. Between 2009 and 2012, 4 children underwent occipital condyle to axial or subaxial spine fixation. One patient had previously undergone posterior fossa surgery for tumor resection, and 1 required decompression at the time of operation. Two patients underwent preoperative deformity reduction using traction. One child had a Chiari malformation Type I. Each procedure was performed using polyaxial screw-rod constructs with intraoperative neuronavigation supplemented by a custom navigational drill guide. Smooth-shanked 3.5-mm polyaxial screws, ranging in length from 26 to 32 mm, were placed into the occipital condyles. All patients successfully underwent occipital condyle to cervical spine fixation. In 3 patients the construct extended from C-0 to C-2, and in 1 from C-0 to T-2. Patients with preoperative halo stabilization were placed in a cervical collar postoperatively. There were no new postoperative neurological deficits or vascular injuries. Each patient underwent postoperative CT, demonstrating excellent screw placement and evidence of solid fusion. Occipital condyle fixation is an effective option in pediatric patients requiring occipitocervical fusion for treatment of deformity and/or instability at the CVJ. The use of intraoperative neuronavigation allows for safe placement of screws into C-0, especially when faced with a challenging patient in whom fixation to the occipital bone is not possible or is less than ideal.</jats:p>

CT-based morphometric analysis of the occipital condyle: focus on occipital condyle screw insertion

“…A promising technique is segmental occipital condyle screw (OCS) fixation. 1,3,5,6,8,[11][12][13][14][15][16][17]21,[24][25][26][27] A few anatomical, 5,6,12,14-17, 21,26 biomechanical, 8,24,27 and clinical 1,3,6,11,13,25 studies have identified the feasibility of OCS placement for OCJ fixation. Advantages of the OCS include a decreased length of the lever arm, longer screw length, a low profile that leaves more available bony surface area for grafting, and avoidance of dramatic rod contouring.…”

Correction of clivoaxial angle deformity in the setting of suboccipital craniectomy: technical note

“…Initially described in 2008 by La Marca et al, 15 then further investigated by Kosnik-Infinger et al 13 and Uribe and colleagues 16,17,25 via radiological and cadaveric analysis, the technique has since been shown to be a viable method to fuse the occiput and cervical spine. Specifically, it has been used in a pediatric setting of craniocervical instability from tumor surgery, craniovertebral anomalies, and prior suboccipital decompression.…”

“…Specifically, it has been used in a pediatric setting of craniocervical instability from tumor surgery, craniovertebral anomalies, and prior suboccipital decompression. 2,13 There are biomechanical data demonstrating that condylar screws provide stiffness in flexion, extension, and lateral and axial support equivalent to that provided with the currently available constructs for OCF. 26 The technique involves placing occipital condyle screws, usually with the aid of neuronavigation.…”

Posterior Instrumentation of the Cervical Spine in Children: Literature Review

“…В последние шесть лет винтовая фиксация шейного отдела позвоночника у детей получила широкое распространение [2,6,8,10,13,16,20,23,26,29,33,35,40,42,43,47,51,53]. Использование винтовых конструкций для лечения патологии позвоночника позволяет создавать надежный каркас для дальнейшего спондилодеза [4,13,22,43], интраоперационно выполнять посегментарную редукцию смещений [13,33,41,43], избегать длительного применения гало-аппарата [4,8,9,11,13,14,18,32,43], является биомеханически надежным видом фиксации, поскольку при 3-колонной системе распределения нагрузки тела позвонков и передняя колонна несут 36 % опорной нагрузки, а задние структуры шейного отдела позвоночника берут на себя больший вес (64 %).…”

“…КТ-морфометрия С 2 позвонка показала, что транспедикулярное проведение винтов размером от 3,5 на 14,0 мм в С 2 возможно у 40-70 % детей старше 2 лет [10,29], при этом ширина и высота ножки примерно одинаковы. В клинической практике транспедикулярная и интерартикулярная фиксация С 2 продемонстрировали надежность и безопасность при использовании у детей [8,13,14,17,23,26,27,37,43,46].…”