Anatomy 2 - Equine Hindlimb, Joints and Recip Apparatus

drraythe's version from 2015-06-05 22:55


Question Answer
what features allow a good, stable hip (coxal) joint?deep acetabulum, deepened more by labrum acetabulare, transverse acetabular ligament, and a capacious (roomy) joint capsule (also holds articular surfaces together)
what ligaments/structures stabilize the hip joint? (3)(1) adj. mm help stabalize (2) lig of head of the femur (very stout, extends from acetabular fossa to the fovea capitis with the intra-articular portion enclosed in the synovial membrane) (3) THE ACCESSORY LIG** (unique to horse)
**unique about accessory lig? where does it extend to/from? what does it DO?UNIQUE TO HORSE. extends from prepubic tendon, through the acetabular notch, to end in the fovea capitis (close to the lig of the head of the femur). It considerably limits inward rotation (pronation) as well as abduction- assists in general stability of the joint (stabilize, make sure propulsion force isn't lost)
how does the ilium usually lie? how does the position of the hip assist in concussion absorption?ilium=usually 30-35* inclined to the horizontal plane. Hip= usually partially flexed at 110-115*, so it absorbs concussion
how is the hip joint protected from injury?by the greater trochanter (so the G.T. gets bruised/bursa injured/fractures)
what is the largest single joint of the horse body?stifle
what kind of joint is the stifle? explain component bones/joints/etccompound! femoropatellar (gliding), femorotibial (simple condylar) joints. Bones are the distal femur, prox tibia, and patella
joint capsules of the stifle?femoropatellar (between trochlea of femur and patella), M+L femorotibial (between condyles of femur and condyles of tibia)
what are the synovial sacs of the stifle, and how do they communicate?(1) femoropatellar sac (2) lateral femorotibial sac (3) medial femorotibial sac. *communication: 1+3 comunicate 100% of the time. 1+2 communicate 25% of the time. 2+3 never communicate!
what are the communications of the stifle joint?femoropatellar+medial femorotibial sac (100% of the time) and femoropatellar sac and lateral femorotibial sac (25% of the time)
which portion of the femur is very important in the patellar lock?the LARGER, medial RIDGE of the trochlea
which trochlear ridge of the femur is bigger?medial. important in the patellar lock
explain the articulating stifle surface of the femur (resting vs gliding surfaces) ?resting surface= prox part of trochlea which faces craniodorsally. Gliding surface= below resting surface (see pic)
where does the patella sit?in the tendon of insertion of the quads
what is the name of the special horse-specific structure of the patella in the horse, and where does it lie?PARAPATELLAR FIBROCARTILAGE on the medial angle
describe the articular surface of the patella? (specifics)2 SURFACES: RESTING SURFACE is short, distal. The GLIDING SURFACE is long and proximal.
2 major fxns of the patella?(1) provides the quads a large, gliding surface over the trochlea of the femur in both flex and exten. (2) protects the tendon of insertion of the mm from excessive friction
what do the medial and lateral menesci do, what joint are they part of?femorotibial joint, they are NOT designed to form a joint, they ARE for minimizing incongruence between the two bones
what are the 5 groups of the ligaments of the stifle?(1) patellar ligs (2) collateral ligs (3) cruciate ligs (4) meniscal ligs (5) femoropatellar ligs
what are the patellar ligaments? where do they attach? what are they actually?medial, middle, and lateral. attach from the sides of the patella to the TIBIAL TUBEROSITY. They are actually tendons of insertion of the quadriceps femoris m.
what are the collateral ligs of the stifle? where do they attach?M and L, from epicondyle of femur to condyle of tibia (M collat lig) and head of femur (L collat lig)
what is the medial parapatellar fibrocartilage doing?runs with Medial (not middle) patellar lig, since M trochlea of femur is bigger (patellar lock) its got longer to go.
what are the cruciate ligs of the stifle? how do they run? what covers them?CR and CA. Cr= runs caudoproximally from fossa of the spine of the tibia to the lateral wall of the intercondyloid fossa of the femur. Ca= cranioproximally,from popliteal notch of tibia to the cr part of intercondyloid fossa of the femur. THEY ARE COVERED BY SYNOVIAL MEMBRANE, being intra-articular
what are the meniscal ligs? what do they attach to?there are 4 ligaments! they attach Cr and Ca hors of the menesci to the Cr and Ca intercondylar areas of the tibia
what are the femoropatellar ligaments? where do they run?M+L. M= attach to parapatellar fibrocartilage. BOTH attach Ca to the femoral epicondyles, from the sides of the patella. Both also fuse w/joint capsule fibrous layer
movements of the stifle are? (how does it start, main mvts, what are the limiting ligaments, how are the joints moving?)start partially flexed (concussion absorption), main mvt is flex/exten (some rotation), the CRUCIATES limit hyperextension (cr) and hyperflexion (both). Both of the joints move in unison (femoropatellar and femorotibial)
how much mm activity is there during the patellar/stifle lock?virtually none
what mm brings about the the patellar lock? what does its action do? explain how it all works.Quadriceps femoris. It moves the patella which glides proximally over the medial ridge of the trochlea on which the parapatellar lig hooks and rests. The M. trochlear ridge now protrudes through the loop formed by the medial and middle patellar ligs and the patellar fibrocartilage. Thus, stifle locked in extension.
Explain how the medial trochlear ridge plays a role in the patellar locking mechanismparapatellar lig hooks over it, and it sticks out now on either side of the parapatellar lig+ med and middle patellar ligs
when does the patellar lock happen? (in terms of weight bearing)when the horse bears BW on only one limb-- angle of joint reaching up to 145-150* (if both limbs bearing weight, angle would be 135*)
what is common in foals in the stifle, but they usually grow out of it?patella luxation
Arthrocentesis of the lateral femorotibial joint cavity where?between the long digital extensor and the lateral collateral ligament
arthrocentesis of the medial femorotibial joint cavity where?between the medial patellar lig and the medial collateral ligament
arthrocentesis of the femoropatellar joint cavity where?Ca to the lateral patellar lig, close to the patella itself
how many bones in tarsus? how many rows? mvt compared to carpus?6, two rows, less mvt than in carpus
what is in the prox tarsal row? (L to M)Calcaneus (fibular tarsal), talus (tibial tarsal)
what is in the distal tarsal raw? (M to L)Central, T1+2, T3, (VASCULAR CANAL HERE for perforating tarsal artery), T4
what are the (major group) articulations of the tarsus?(1) tarsocrural (2) intertarsal (3) tarsometatarsal
what is involved in the tarsocrural articulation?between the cochlea of tibia and trochlea of the talus.
describe the trochlea of the talus. why is it like this?it is OBLIQUE and LATERALLY DIRECTED (bottom of it is pointed laterally) so outward mvt of hock in motion (while stifle and toe turned inward) due to prox. gliding of tibia over trochlea. WHY? b/c during flexion, the obliquity of the trochlea assists in turning stifle outward, this AVOIDING CA THORACIC WALL
what are the intertarsal articulations? what are the articulations between?PROX+DISTAL. The PROX= between talus/calcaneus proximally and central/T4 distally. DISTAL= between TC and T4 prox and laterally, and the T1+2 and T3 distally
what are the tarsometatarsal articulations? what is it between?between the distal row of tarsals and the metatarsal bones
what is the joint capsule of the tarsus? where does it attach? describe its composition.COMMON joint capsule. from distal end of tibia to peri-articular surfaces of the metatarsal bones. The deep surface attaches to component bones. The PLANTAR and DORSAL surfaces are THICK (may be partly cartilaginous on PLANTAR surface)
What/where is BOG SPAVIN? why does this happen?the PROXIMAL END of the common joint capsule of the tarsus is THIN at the top, so it can bulge out with synovial fluid accumulation (this is the "bog spavin")
where do you inject to affect the tarsocrural joint and the prox. intertarsal joints?the dorsal pouch
how many synovial sacs are in the tarsal joint? which is best formed/ which communicate?4 synovial sacs one for each joint and named accordingly. The best formed/most important is the tibiotarsal or tarsocrural sac. It communicated with the PROx intertarsal sac. Other sacs rarely communicate.
what are the ligaments of the tarsus?medial collateral lig, lateral collateral lig, *long plantar lig, dorsal lig, *accessory (check) lig
describe the parts, location, etc of the medial collateral ligament of the talusfrom medial malleolus to the talus and prox ends of the II and III metatarsals. There are TWO portions, the LONG AND SHORT parts. The short is enclosed by the long inserts on the talus
what are the parts, location, etc of the lateral collateral lig of the talusfrom the lateral malleolus to calcaneus,T4, and III and IV metatarsals. It also has two portions, long and short (which is under the long) and inserts caudally on talus and calcaneus
where/what does the long plantar ligament do?occupies lateropalmar aspect of hock (from calcaneus to T4 and metatarsals) **stabilizes calcaneus when under force of common calcaneal tendon
what is "curb"?when the LONG PLANTAR LIGAMENT OF THE TARSUS is swollen, due to strain. causes convexity of plantar surface= curb
what is the shape/ location of the dorsal lig of the tarsus?Triangular, from distal tuberosity on medial part of talus and insert on the II and III metatarsals, as well as on central and third tarsals
What is the accessory lig of the tarsus aka? what is it made from? how does it compare to the forlimb?aka check lig. distal extension of the plantar part of DDF. NOT ALWAYS PRESENT, unlike in the forlimb where it is
what is the cunean tendon? what are its divisions?tendon of cr tibial m, divides into dorsal limb inserting on Mt3 and a MEDIAL limb (the cunean tendon) which inserts on T1+2
what is the bursa of the tarsus? where is it?subtendinous/cunean bursa, under the cunean tendon over the medial collateral lig of the hock
where are there tendon sheaths in the tarsus?all tendons EXCEPT SDF passing over the hock have tendon sheaths
what is involved in the "tarsal synovial sheath" ?the lateral digital flexor and the ca tibial mm
what is the normal conformation of the tarsus?usually partially flexed (concussion absorption)
what is the hardest worked joint in the horse's body?tarsus
what is spavin?strains and stresses on the tarsus cause this
what joints are involved in the reciprocal apparatus?stifle and hock move in unison (both flex or both extend)
2 main components of the reciprocal apparatus?peroneus tertius (cr) and SDF (ca)
what are the cranial structures of the reciprocal apparatus?Peroneus tertius (ENTIRELY TENDINOUS). origin= extensor fossa of femur. insertion= cr surface of prox end of MtIII, T3, talus and T4
what are the ca structures of the reciprocal apparatus?SDF. (between 2 heads of gastroc), almost entirely tendinous. Origin= supracondylar fossa of femur. insertion= tuber calcaneum and P1 and P2. (some ppl would include gastroc here too)
what happened if there is abnormal, jerky flexing of the hock?rupture of the peroneus tertius
what happened if the hock drops to the ground?both peroneus tertius and SDF ruptured

Recent badges