The articular facets on the inferior aspect of the occipital condyles, articulate with the superior articular facets of the first cervical (atlas) vertebra, to form the atlanto-occipital joint. The present case, reports the asymmetrical dimensions of the facets on the occipital condyles of a human dried skull. The anatomico-radiological study of asymmetrical articular facets on the occipital condyles, may be helpful for academicians, neuro-surgeons, clinicians and radiologists in day to day clinical practice.
During extensive osteological study of 150 dry skulls in the Department of Anatomy, Vardhman Mahavir Medical college, an unusual Paramedian Occipital (POC) condyle was detected in the occipital bone of a cadaveric skull. The anatomical details of this unusual occipital condyle were carefully studied and its morphometric measurements taken. A coronal multiplanner reformatted image and a volume rendered image were taken to study radiological details and establish significant clinical correlation. Precise understanding of anatomy of craniovertebral junction and its anomalies have become immensely important for the present day surgeon during orthopaedic and neurosurgical procedures of this region . Technical advancements in imaging modalities such as CT and MRI scans further signify the importance of these anatomical variations ,which are often missed in routine examination. Osteological study combined with radiological details of the paramedian occipital condyle in the present case aims to emphasize the importance of bony anomalies in the craniovertebral region and their role in diagnosis and appropriate treatment of neurovascular compression syndromes of craniovertebral junction. The present study highlights anatomical details, clinical relevance and embryological basis of such a rare unusual paramedian occipital condyle.
The occipital sinus (OS) lies in the attached margin of the faix cerebelli in the internal occipital crest of the occipital bone. The OS extends from the foramen magnum to the confluence of sinuses. Standard textbooks and research reports do not describe in detail any variation in the groove for the occipital sinus.
Atlanto-occipital fusion may be symptomatic or asymptomatic in nature. The anomaly may be incidentally detected at autopsies or during routine cadaveric dissections. The fusion of the atlas with occipital bone may result in the compression of vertebral artery and first cervical nerve.
A Median Occipital Condyle is a rare occurrence. We have not found any clinical studies in the literature and myelopathy due to a median condyle has been reported once before. Myelopathy due to anomalies of the craniovertebral junction is rare in neurosurgical practice. We describe a case of a 72-year-old man presenting with progressive myelopathy related to a median occipital condyle located at the anterior foramen magnum region.
Timing of fusion of the spheno-occipital synchondrosis (SOS) is correlated with age. Previous research, however, has demonstrated variation in the timing of closure among different global populations. The present study aims to quantify the timing of SOS fusion in Malaysian individuals as visualised in multi-detector computed tomography (CT) scans and to thereafter formulate age estimation models based on fusion status. Anonymised cranial CT scans of 336 males and 164 females, aged 5-25 years, were acquired from the National Institute of Forensic Medicine, Hospital Kuala Lumpur and Department of Diagnostic Imaging, Hospital Sultanah Aminah. The scans were received in DICOM format and reconstructed into three-dimensional images using OsiriX. The SOS is scored as open, fusing endocranially, fusing ectocranially or completely fused. Statistical analyses are performed using IBM SPSS Statistics version 24. Transition analysis (Nphases2) is then utilised to calculate age ranges for each stage. To assess the reliability of an observation, intra- and inter-observer agreement is quantified using Fleiss Kappa and was found to be excellent (κ=0.785-0.907 and 0.812). The mean (SD) age for complete fusion is 20.84 (2.84) years in males and 19.78 (3.35) years in females. Transition ages between Stages 0 and 1, 1 and 2, and 2 and 3 in males are 12.52, 13.98 and 15.52 years, respectively (SD 1.37); in females, the corresponding data are 10.47, 12.26 and 13.80 years (SD 1.72). Complete fusion of the SOS was observed in all individuals above the age of 18 years. SOS fusion status provides upper and lower age boundaries for forensic age estimation in the Malaysian sample.
Matched MeSH terms: Occipital Bone/growth & development