Feasibility of occipital condyle screw placement for occipitocervical fixation

A cadaveric study and description of a novel technique

Juan S. Uribe, Edwin Ramos, Fernando Vale Diaz

Research output: Contribution to journalArticle

42 Citations (Scopus)

Abstract

Study Design: Occipital-cervical (OC) stabilization using occipital condyle fixation with a polyaxial screw-rod construct is described. Objectives: To describe a novel technique and initial radiographic results for posterior OC fixation using the occipital condyles for cranial fixation. Summary of Background Data: Stabilization of the OC junction remains a challenge. Owing to the regional anatomy and the poor occipital bone purchase, multiple attachment points to the occipital bone are required to increase construct rigidity. To address these issues, we propose a novel OC fixation technique using polyaxial occipital condyle screws for cranial purchase. Methods: The OC junction was exposed posteriorly in silicone-injected cadaver heads. Polyaxial titanium screws (3.5 mm) were inserted bicortically solely into the occipital condyles; C1 lateral masses and C2 pedicles, or transarticularly through C1-C2, followed by fixation to a 3-mm rod. Drilling was guided by anatomic landmarks and fluoroscopy. Computerized tomography scans were obtained. Condylar screw angles and lengths were analyzed with respect to historical morphometric condyle measurements and with respect to neurovascular structures. Results: The condylar entry point was 4 to 5-mm lateral to the foramen magnum on the axial plane, and 1 to 2-mm rostral to the atlantooccipital joint. The mean angle of medialization was 17 degrees (range: 12 to 22 degrees). In the sagittal plane, the maximal superior screw angulation was 5 degrees. The mean screw length to obtain bicortical purchase was 22 mm (range: 20 to 24 mm). The hypoglossal canal was uninterrupted during its full course. The jugular bulb, carotid, and vertebral arteries were not injured by condyle screw placement. No fractures were identified. Conclusion: Condyle screws can be placed without injury to neurovascular structures. OC junction fixation using polyaxial occipital condyle screws is feasible and can be considered a salvage technique or an alternative where other fixation techniques are not available.

Original languageEnglish (US)
Pages (from-to)540-546
Number of pages7
JournalJournal of Spinal Disorders and Techniques
Volume21
Issue number8
DOIs
StatePublished - Dec 1 2008
Externally publishedYes

Fingerprint

Bone and Bones
Occipital Bone
Regional Anatomy
Anatomic Landmarks
Foramen Magnum
Vertebral Artery
Fluoroscopy
Silicones
Titanium
Carotid Arteries
Cadaver
Neck
Joints
Head
Tomography
Wounds and Injuries

Keywords

  • craniocervical fusion
  • craniocervical junction
  • craniovertebral junction
  • occipital condyle
  • occipital condyle screws
  • occipitocervical fusion
  • occipitocervical instability
  • occipitocervical junction

ASJC Scopus subject areas

  • Surgery
  • Orthopedics and Sports Medicine
  • Clinical Neurology

Cite this

@article{6c3d4109535c4d5cbc94a9cf1234ba2b,
title = "Feasibility of occipital condyle screw placement for occipitocervical fixation: A cadaveric study and description of a novel technique",
abstract = "Study Design: Occipital-cervical (OC) stabilization using occipital condyle fixation with a polyaxial screw-rod construct is described. Objectives: To describe a novel technique and initial radiographic results for posterior OC fixation using the occipital condyles for cranial fixation. Summary of Background Data: Stabilization of the OC junction remains a challenge. Owing to the regional anatomy and the poor occipital bone purchase, multiple attachment points to the occipital bone are required to increase construct rigidity. To address these issues, we propose a novel OC fixation technique using polyaxial occipital condyle screws for cranial purchase. Methods: The OC junction was exposed posteriorly in silicone-injected cadaver heads. Polyaxial titanium screws (3.5 mm) were inserted bicortically solely into the occipital condyles; C1 lateral masses and C2 pedicles, or transarticularly through C1-C2, followed by fixation to a 3-mm rod. Drilling was guided by anatomic landmarks and fluoroscopy. Computerized tomography scans were obtained. Condylar screw angles and lengths were analyzed with respect to historical morphometric condyle measurements and with respect to neurovascular structures. Results: The condylar entry point was 4 to 5-mm lateral to the foramen magnum on the axial plane, and 1 to 2-mm rostral to the atlantooccipital joint. The mean angle of medialization was 17 degrees (range: 12 to 22 degrees). In the sagittal plane, the maximal superior screw angulation was 5 degrees. The mean screw length to obtain bicortical purchase was 22 mm (range: 20 to 24 mm). The hypoglossal canal was uninterrupted during its full course. The jugular bulb, carotid, and vertebral arteries were not injured by condyle screw placement. No fractures were identified. Conclusion: Condyle screws can be placed without injury to neurovascular structures. OC junction fixation using polyaxial occipital condyle screws is feasible and can be considered a salvage technique or an alternative where other fixation techniques are not available.",
keywords = "craniocervical fusion, craniocervical junction, craniovertebral junction, occipital condyle, occipital condyle screws, occipitocervical fusion, occipitocervical instability, occipitocervical junction",
author = "Uribe, {Juan S.} and Edwin Ramos and {Vale Diaz}, Fernando",
year = "2008",
month = "12",
day = "1",
doi = "10.1097/BSD.0b013e31816d655e",
language = "English (US)",
volume = "21",
pages = "540--546",
journal = "Journal of Spinal Disorders",
issn = "1536-0652",
publisher = "Lippincott Williams and Wilkins",
number = "8",

}

TY - JOUR

T1 - Feasibility of occipital condyle screw placement for occipitocervical fixation

T2 - A cadaveric study and description of a novel technique

AU - Uribe, Juan S.

AU - Ramos, Edwin

AU - Vale Diaz, Fernando

PY - 2008/12/1

Y1 - 2008/12/1

N2 - Study Design: Occipital-cervical (OC) stabilization using occipital condyle fixation with a polyaxial screw-rod construct is described. Objectives: To describe a novel technique and initial radiographic results for posterior OC fixation using the occipital condyles for cranial fixation. Summary of Background Data: Stabilization of the OC junction remains a challenge. Owing to the regional anatomy and the poor occipital bone purchase, multiple attachment points to the occipital bone are required to increase construct rigidity. To address these issues, we propose a novel OC fixation technique using polyaxial occipital condyle screws for cranial purchase. Methods: The OC junction was exposed posteriorly in silicone-injected cadaver heads. Polyaxial titanium screws (3.5 mm) were inserted bicortically solely into the occipital condyles; C1 lateral masses and C2 pedicles, or transarticularly through C1-C2, followed by fixation to a 3-mm rod. Drilling was guided by anatomic landmarks and fluoroscopy. Computerized tomography scans were obtained. Condylar screw angles and lengths were analyzed with respect to historical morphometric condyle measurements and with respect to neurovascular structures. Results: The condylar entry point was 4 to 5-mm lateral to the foramen magnum on the axial plane, and 1 to 2-mm rostral to the atlantooccipital joint. The mean angle of medialization was 17 degrees (range: 12 to 22 degrees). In the sagittal plane, the maximal superior screw angulation was 5 degrees. The mean screw length to obtain bicortical purchase was 22 mm (range: 20 to 24 mm). The hypoglossal canal was uninterrupted during its full course. The jugular bulb, carotid, and vertebral arteries were not injured by condyle screw placement. No fractures were identified. Conclusion: Condyle screws can be placed without injury to neurovascular structures. OC junction fixation using polyaxial occipital condyle screws is feasible and can be considered a salvage technique or an alternative where other fixation techniques are not available.

AB - Study Design: Occipital-cervical (OC) stabilization using occipital condyle fixation with a polyaxial screw-rod construct is described. Objectives: To describe a novel technique and initial radiographic results for posterior OC fixation using the occipital condyles for cranial fixation. Summary of Background Data: Stabilization of the OC junction remains a challenge. Owing to the regional anatomy and the poor occipital bone purchase, multiple attachment points to the occipital bone are required to increase construct rigidity. To address these issues, we propose a novel OC fixation technique using polyaxial occipital condyle screws for cranial purchase. Methods: The OC junction was exposed posteriorly in silicone-injected cadaver heads. Polyaxial titanium screws (3.5 mm) were inserted bicortically solely into the occipital condyles; C1 lateral masses and C2 pedicles, or transarticularly through C1-C2, followed by fixation to a 3-mm rod. Drilling was guided by anatomic landmarks and fluoroscopy. Computerized tomography scans were obtained. Condylar screw angles and lengths were analyzed with respect to historical morphometric condyle measurements and with respect to neurovascular structures. Results: The condylar entry point was 4 to 5-mm lateral to the foramen magnum on the axial plane, and 1 to 2-mm rostral to the atlantooccipital joint. The mean angle of medialization was 17 degrees (range: 12 to 22 degrees). In the sagittal plane, the maximal superior screw angulation was 5 degrees. The mean screw length to obtain bicortical purchase was 22 mm (range: 20 to 24 mm). The hypoglossal canal was uninterrupted during its full course. The jugular bulb, carotid, and vertebral arteries were not injured by condyle screw placement. No fractures were identified. Conclusion: Condyle screws can be placed without injury to neurovascular structures. OC junction fixation using polyaxial occipital condyle screws is feasible and can be considered a salvage technique or an alternative where other fixation techniques are not available.

KW - craniocervical fusion

KW - craniocervical junction

KW - craniovertebral junction

KW - occipital condyle

KW - occipital condyle screws

KW - occipitocervical fusion

KW - occipitocervical instability

KW - occipitocervical junction

UR - http://www.scopus.com/inward/record.url?scp=60849091374&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=60849091374&partnerID=8YFLogxK

U2 - 10.1097/BSD.0b013e31816d655e

DO - 10.1097/BSD.0b013e31816d655e

M3 - Article

VL - 21

SP - 540

EP - 546

JO - Journal of Spinal Disorders

JF - Journal of Spinal Disorders

SN - 1536-0652

IS - 8

ER -