Transcript Ch6- pt6
Appendicular Skeleton- Hind Limb • Connected to the axial skeleton at sacroiliac joint Pelvic Limb: • Pelvis – Ilium – Pubis – Ischium • • • • • • Femur Tibia Fibula Tarsal bones (tarsus) Metatarsal bones Phalanges • May be referred to as the os coxae • Develops as three separate bones on each side that fuse into a solid structure. • 2 sides halves join at the pelvic ______________. • Socket of ball and socket joint is the ______________. • Bones are: – _____________ • Cranial most bone of pelvis • “Wings of the ilium” or hips in dogs and cats. • Tuber coxae are “points of the hip” in cattle and horses – _____________ • Most caudal pelvic bone • Tailbone is ischial tuberosity. – _____________ • Smallest of the pelvic bones Pelvis Femur • Long Bone of thigh • Articulates proximally with the ___________ and distally with the ___________ and ____________ • On proximal end is the ball portion of ball and socket joint, called the head. • Proximal end also contains the greater _______________ where muscles attach. • Distal end contains the medial and lateral condyles which form the _____________ (knee) – The trochlea is at the distal end in between the condyles and contains a groove that the patella fits in. – Like the humerus, there are palpable medial and lateral epicondyles • Kneecap is largest ___________ bone in the body. • Formed in the distal tendon of the ____________ femoris muscle on the cranial aspect of the stifle joint. • Helps to protect tendon as it passes down over the trochlea of the femur. • Patellar luxation: when trochlear groove is not deep enough to contain patella so it slips in and out of place. – – – – Usually will cause brief episodes of lameness which can correct. May hear or feel “popping” in and out of place. Found in small, toy breeds most prevalently. Can be surgically corrected. Patella Fabellae • Two small __________ bones located in the proximal gastrocnemius (calf muscle). – Located cranial to the femoral condyles. • Not present in cattle or horses. • Main weight bearing bone of the lower leg (shinbone). • Forms stifle joint proximally with femur. • Forms ___________ (ankle) distally with tarsal bones. • Tibial _______________ continues distally down the femur as the tibial crest. – Where patellar tendon attaches. • Medial __________ is medial to distal articular surface and is called “knob” of ankle. Tibia Fibula • Consists of proximal extremity, shaft, and distal extremity. • Does not support significant weight. • Thin, but complete, in dogs and cats. Horses and cattle do not have shaft of fibula. • Forms lateral ____________ at distal end. • aka ankle or “hock” • Consists of two rows of tarsal bones (similar to carpal bones in wrist). – Proximal row is named and distal row is numbered. – Proximal row: tibial tarsal (with ____________), fibular tarsal (with ____________), and central tarsal bone • Calcaneal tuberosity forms the point of the hock. Site of attachment for tendon of the gastrocnemius muscle (aka ___________ tendon) Tarsal Bones Metatarsal Bones • Almost identical to metacarpals – exception: dogs and cats usually only have metatarsals II – V • Horses/Cattle same as front leg. Almost identical to phalanges on thoracic limb exception: dogs and cats usually only have digits II – V Horses/Cattle same as front leg. • Bones that form in soft organs (__________) • Are not found in every animal • Examples – os cordis: in heart of cattle and sheep that supports the valves – os penis: in penis of dogs, beaver, raccoons, and walruses that partially surrounds the urethra – os rostri: in nose of swine that strengthens snout for rooting/digging Visceral Skeleton • Junctions between bones • Can be moveable or immovable. • Arthro and articular refer to joints. Joints • 3 Types of joints: – Fibrous Joints (____arthroses) • Immovable; joined by fibrous tissue • Found in sutures of skull bones, splint bones in horses – Cartilaginous Joints (_______arthroses) • Slightly moveable; rocking motion • Vertebral disks between vertebrae, Pelvic and mandibular symphisis – Synovial Joints (___arthroses) • Freely moveable • Shoulder, stifle, elbow, etc Characteristics of Synovial Joints – Have Articular surfaces on bones • Articular (__________) cartilage covering articular surfaces – Fluid-filled joint cavity (joint space) – Enclosed by a joint ____________ • Synovial membrane- outer membrane that produces: – Synovial fluid- lubricates joint surfaces – Ligaments – fibrous (__________) connective tissue that join bones to other bones. Synovial Joint Movements • Flexion and Extension – Opposite movements – Increase (extension) or decrease (flexion) angle between two bones • Adduction and Abduction – Opposite movements – Move an extremity toward (Adduction) or away from (Abduction) medial plane • Rotation – Twisting movement of a part on its own axis • Circumduction – Movement of an extremity so that the distal end moves in a circle Types of Synovial Joints • Hinge Joints – One joint surface swivels around another – Only capable of flexion and extension • Gliding Joints – Rocking motion of one joint surface on another – Primarily capable of flexion and extension – Abduction and adduction possible in humans not dogs/cats • Pivot Joints – One bone pivots (rotates) on another – Only capable of rotation • Ball-and-socket joints – Allow for all joint movements