LAB: SKELETAL SYSTEM All the bones of the skeleton can be placed into one of four categories based on the specific morphology of the bone. Long Bones < humerus, ulna, radius, femur < tibia, fibula, phalanges Flat Bones < cranial bones, ribs, sternum, scapula Two additional classifications of bone are sutural a.k.a. Wormian and sesamoid. These classifications are based on location. Sutural bones can exist as irregularly shape bones which form between the sutures of the cranial bones. Sesamoid bones, i.e., patella, are bones located within tendons. Bone surfaces are punctuated with structural features called bone marking. These features provide surface area for articulations, support, muscle attachments etc. Axial Skeleton THE SKULL The skull is created by the cranial (8) and facial (14) bones. Name them. How many bones comprise the eye orbit? Name these bones. How many bones comprise the nasal cavity? Name these bones. Cranial bones are joined by joints called sutures. Each suture has a specific name. < coronal suture < sagittal suture < lambdoidal suture < squamous suture < frontozygomatic suture < sphenoparietal suture Frontal View Skull Bone Markings < supraoribital foramen < infraorbital foramen < middle nasal concha < inferior nasal concha < mental foramen Side View Skull Bone Markings < external acoustic meatus < condylar process of mandible < mastoid process of temporal bone < mandibular notch < coronoid process of mandible < zygomatic process of temporal bone Short Bones < carpals, tarsals Irregular Bones < facial bones, vertebrae -1-
Midsagittal View Skull Bone Markings < crista galli of ethmoid bone < cribriform plate of ethmoid bone < ethmoidal sinus < internal acoustic meatus < sella turcica < styloid process of temporal bone Inferior View Skull Bone/Bone Markings < lateral pterygoid process of sphenoid bone < carotid canal < stylomastoid foramen < foramen magnum < mandibular fossa < styloid process of temporal bone < jugular fossa < occipital condyle < vomer bone Superior View Skull Bone Marking < cribriform plate of ethmoid bone < optic canal < petrous region of temporal bone < foramen magnum < crista galli of ethmoid bone < anterior cranial fossa < sella turcica < internal acoustic meatus < posterior cranial fossa How does the fetal skull differ from that of an adult? It has pronounced sites of ossification termed fontanels (soft spots). Fontanels are regions of fibrous connective tissue. < anterior (frontal) fontanel < posterior (occipital) fontanel < anterolateral (sphenoid) fontanel < posterolateral (mastoid) fontanel Identify all the paranasal sinuses. These include the frontal sinus, ethmoidal sinus, sphenoidal sinus and the maxillary sinus. Where does the hyoid bone fit into the axial skeleton? It s a non-articulating bone which is suspended from the styloid processes of the temporal bones. What s the function of the hyoid bone? < speech < swallowing -2-
VERTEBRAL COLUMN The vertebral column is a longitudinal collection of irregular bones called vertebrae. Sandwiched between each vertebra is a cushion created by an intervertebral disc. The vertebral column can be divided into collections of similarly shaped vertebrae - cervical, thoracic, lumbar, sacral and coccygeal. < 7 cervical (u have breakfast at seven) < 12 thoracic (u have lunch at twelve) < 5 lumbar (u have supper at five) < 1 sacrum (u have one snack before bed) < 1 coccyx (a snack of crackers before bed) Vertebrae Bone Markings < spinous process < vertebral canal < transverse canal < body (a.k.a. centrum) < transverse process Sacrum Bone Markings < ala < anterior sacral foramina < posterior sacral foramina < median sacral crest A single disc structurally contains two concentric circles - an outer ring termed the annulus fibrosus and an inner ring termed the nucleus pulposus. Together these rings of connective tissue provide a cushion between individual vertebrae. < annulus = fibrocartilage < nucleus = elastic connective tissue RIB CAGE Floating vs. Nonfloating Ribs True vs. False Ribs The rib cage is created by the direct or indirect attachment of the 24 ribs to the sternum (anterior) and/or vertebrae (posterior). The ribs are categorized based on how they are attached to the sternum. Rib Bone Markings < articulation site for costal cartilage < costal groove Sternum Bone Markings < jugular notch < manubrium < xiphoid process -3-
APPENDICULAR SKELETON The appendicular skeleton is divided into two regions called girdles. These include the pectoral and pelvic girdles. Name all the bones which comprise each girdle. Clavicle/Collarbone < medial articulation/extremity bone/bone marking is? < lateral articulation/extremity bone/bone marking is? Scapula/Shoulder Blade < lateral articulation bone/bone marking is? < acromian process < coracoid process < glenoid cavity < superior angle < inferior angle < spine Humerus < distal articulation bones/bone markings are? < head < capitulum & trochlea < olecranon fossa Ulna/ Radius < ulnar styloid process (lateral) < trochlear notch < olecranon < radius styloid process (medial) < distal articulations bone/bone marking is? Pelvis/Hip (two os coxa bones) < pubic symphysis < acetabulum < obturator foramen < ilium with the greater sciatic notch < ischium with the lesser sciatic notch < pubis with the pubic crest Femur < distal articulations bones/bone markings are? < head & neck < fovea capitis -4-
Tibia < anterior crest < medial malleolus Fibula < lateral malleolus Hands and Feet You should recognize the names of the bones associated with the hands and feet. You will be expected to distinguish between them. There will not be a photo to label. Imbalances Cleft Palate Flatfoot Herniated Disc Hip Dysplasia Kyphosis Lordosis Scoliosis Spina Bifida TMJ Syndrome HOMEOSTATIC IMBALANCES Information failure of hard palate to close; oral cavity directly opens into the nasal cavity high risk of aspiration pneumonia fallen foot arches... standing immobile for long periods of time Nucleus pulposus pokes through the annulus fibrosis; commonly puts pressure on spinal nerves femur head slips from the pelvis acetabulum hunchback, exaggerated thoracic region swayback, exaggerated lumbar curvature lateral bending, commonly thoracic region vertebrae lamina fail to close, spinal cord exposed, monitor levels of alpha fetoprotein pain associated with the temporomandibular joint; causes misalignments, grinding teeth, trauma, arthritis October 16, 2009 (4:43pm) \\Shelves\myfiles\LCCC\a&p hybrid\lab_135\lab.bones.wpd -5-