China
Africa
Explore chapters and articles related to this topic
Musculoskeletal (including trauma and soft tissues)
Published in Dave Maudgil, Anthony Watkinson, The Essential Guide to the New FRCR Part 2A and Radiology Boards, 2017
Dave Maudgil, Anthony Watkinson
The accessory soleus muscle is found in the calf. The arcuate foramen is sited in the posterior arch of the C1 vertebra. Filling of the flexor hallucis and digitorum tendon sheath spaces as well as the posterior subtalar joint space occurs normally in 20% and 10% of ankle arthrograms, respectively.
C1–C2 Transarticular Screw Technique
Published in Alexander R. Vaccaro, Christopher M. Bono, Minimally Invasive Spine Surgery, 2007
Thomas J. Puschak, Paul A. Anderson
During exposure of the laminar arches, one should take care not to injure the vertebral artery. Ebraheim has reported that the medial edge of the vertebral artery groove ranges from 8 to 18 mm from the midline on the superior surface of the C1 lamina (20). Exposure on the superior aspect of the posterior arch of the atlas should not be carried further than 15 mm lateral to midline. In 1% to 2% of cases, the vertebral artery lies in a tunnel, the arcuate foramen, on the superior aspect of the posterior atlantal arch formed by a thin bony arch, the postis ponticulous (21).
Surgical considerations in posterior C1-2 instrumentation in the presence of vertebral artery anomalies: case illustration and review of literature
Published in British Journal of Neurosurgery, 2019
Lee A. Tan, Manish K. Kasliwal, Carter S. Gerard, Vincent C. Traynelis, Ricardo B.V. Fontes
The vertebral artery develops from plexiform anastomoses among the embryonic cervical intersegmental arteries around 5–6 weeks of gestation. The seven intersegmental arteries enlarge and become the subclavian arteries and the VAs arise from the enlarging seven cervical intersegmental arteries and supply the caudal end of the longitudinal neural arteries that develop into the basilar artery. If the first intersegmental artery persists without sufficient growth of the normal VA branch, then the VA takes an anomalous course and enters the spinal canal inferior to the C1 posterior arch after emerging from the C2 transverse foramen, then ascends under the C1 posterior arch and enters the dura without passing through the C1 transverse foramen, becoming the PFIA. When the VA develops but the first intersegmental arterty fails to regress, then a FVA would form. Low-lying PICA and HRVA may be present as natural variations of normal anatomy. With respect to PP, it has been suggested that the arcuate foramen is commonly present in early primates and may be a ruminant of evolution.