Neural Arch
Definition
The posterior bony arch of a vertebra, formed by two pedicles and two laminae meeting at the spinous process. In foetal and neonatal skeletons, the neural arch is unfused to the vertebral body and is a common source of fragment-identification ambiguity when it resembles a rib piece.
- Location
- Posterior bony arch of a vertebra
- Formed by
- Two pedicles, two laminae, spinous process
- Fusion status (young)
- Unfused to vertebral body in foetal/neonatal remains
- Forensic issue
- Can be mistaken for a rib fragment
Common questions
Why does neural arch fusion status matter for age estimation?+
The neural arch fuses to the vertebral body along a known developmental timetable, which helps estimate age in foetal, infant, and juvenile skeletal remains.
What distinguishes a neural arch fragment from a rib fragment?+
A neural arch fragment shows a curved articular process and a pedicle cross-section, whereas a rib fragment has a more uniform curved shaft without those articular features.
Related terms
- Cortical Index
- The ratio of total cortical bone area to total bone cross-sectional area at a defined midshaft location. Used in fragment identification to...
- Fragment Identification
- The assignment of a bone fragment to a specific skeletal element (rib, long-bone shaft, vertebral arch, cranial vault, etc.) and anatomical region,...
- Haversian Canal
- The central vascular channel of an osteon, carrying blood vessels and nerves through the cortical bone. Diameter 20-70 µm in human bone....
- Minimum Number of Individuals (MNI)
- The smallest number of distinct individuals required to account for all skeletal elements present in an assemblage. Determined by identifying the element...
- Osteon
- The basic structural unit of cortical bone: a set of concentric lamellae surrounding a central Haversian canal. Human secondary osteons are roughly...
- Owsley-Mann Protocol
- The fragment identification and triage methodology developed by Douglas Owsley (Smithsonian Institution) and Robert Mann (DPAA) for systematically assigning commingled bone fragments...
- Plexiform Bone
- A microstructural pattern found in the cortical bone of large rapid-growth mammals (bovids, horses, deer) characterised by alternating layers of woven bone...
- Side Determination
- The osteological process of assigning a paired skeletal element (clavicle, humerus, femur, rib, os coxae, etc.) to the left or right side...
- Species Confirmation (DNA)
- PCR-based or sequencing-based confirmation that a bone fragment is of human (Homo sapiens) origin, using human-specific primer sequences or mitochondrial cytochrome b...