Lecture 16 - Disorder of gait Flashcards
What are the types of contractions?
Tonic and phasic
What is tonic contraction?
Constant contraction of muscle fibers that maintains muscular and postural integrity
What is phasic contraction?
Contraction of muscle fiber beyond tonic contraction, via short bursts
What are two types of phasic contraction?
Isotonic and isometric
What is isotonic contraction?
Change in muscle length occurs with contraction
What is isometric contraction?
Contraction does not result in change in muscle length but instead goes against force
What are two types of isotonic contraction?
Concentric and eccentric
What is concentric contraction?
Muscle shortening
What is eccentric contraction?
Muscle lengthening
What are carnivora’s limbs used for?
Manipulation
What are the characteristics of carnivora’s limbs?
more mobile limbs and more flexible back
What are cursorial herbivores limbs used for?
Solely for posture and locomotion
What are the characteristics of cursorial herbivores limbs?
More rigid backs and limbs
What does the Gluteal nn. cause in the hip?
Abduction, flexion, and extension
What does the Obturator n. cause in the hip?
Adduction and flexion
What does the Femoral n. cause in the hip?
Flexion
What does the Sciatic n. cause in the hip?
Extension
What does the Femoral n. cause in the stifle?
Extension
What does the Sciatic n. cause in the stifle?
Extension and flexion
What does the Obturator n. cause in the hock?
Extension
What does the Tibial n. cause in the tarsal jt?
Extension
What does the Fibular n. cause in the tarsal jt?
Flexion
What does the Tibial n. cause in the digital jt?
Flexion
What does the Fibular n. cause in the digital jt?
Extension
What does the Accessory n. cause in the shoulder?
Elevation and advancement
What does the Thoracodorsal n. cause in the shoulder?
Retraction
What does the Long Thoracic n. cause in the shoulder?
Depression
What does the Suprascapular n. cause in the Gleno-humeral joint?
Extension
What does the Radial n. cause in the Gleno-humeral joint?
Extension
What does the Subscapular n. and Pectoral nn. cause in the Gleno-humeral joint?
Adduction
What does the Axillary n. cause in the Gleno-humeral joint?
Flexion
What does the Thoracodorsal n. cause in the Gleno-humeral joint?
Abduction
What does the Radial n. cause in the elbow?
Extension and supination
What does the Musculocutaneous n. cause in the elbow?
Flexion and supination
What does the Median n. cause in the elbow?
Pronation
What does the Radial n. cause in the carpal joints?
Extension
What does the Median n. cause in the carpal joints?
Flexion
What does the Radial n. cause in the digital joints?
Extension
What does the median n. and ulnar n. cause in the digital joints?
Flexion
What damage does a lesion of the suprascapular n. cause to the muscles?
Paralysis of the supraspinatus and infraspinatus
What dysfunction in movement would you see with a lesion to suprascapular n.?
No affect on standing posture
Shoulder slip
What is a shoulder slip?
May result in obvious lateral movement of shoulder joint during walking
What happens to the muscles over time?
Wasting of muscle along scapular spine
What is one way to damage the suprascapular n.
Overabduction or violent retraction of scapula may stretch nerve agains scapula
What are the consequences of radial n. palsy?
Paralysis of elbow extensors and carpal digital extensors
Anesthesia of skin territory
What is the radial nerve related to? What is the downside of that?
Humerus. If broken can injure nerve
What happens if the injury to the radial n. occurs at the proximal to middle part of brachium?
All three dysfunctions
What happens if the injury to the radial n. occurs at the distal part of the brachium?
Carpal and digital extensor paralysis
Anesthesia of skin
What happens if the injury occurs beyond distal motor branches of the radial n. ?
Skin numbness
Where do the motor branches stop in the radial n.?
Distal antebrachium or manus
What happens when the damage to the radial n. is proximal to the origin of tricep innervation?
Very serious
No flexion of elbow
No weight bearing on limb
Foot drags on dorsal surface
What are the consequences of femoral n. palsy?
Paralysis of quadriceps
What happens when the quadriceps are paralyzed?
Precludes fixation of stifle joint
Limb cant support weight
Can the animal compensate with a femoral n. palsy?
No
What is locked patella?
Neuromuscular disorder; persistent and temporary lock
What is a persistent lock?
Section of medial patellar ligament affected
What is a temporary lock?
Can be fixed by startling the horse into a sudden movement
What happens with a rupture of the peronius tertius?
Permits extension of hock while stifle is flexed
What is the reciprocal mechanism?
Ensure stifle and hock in unison
What tendons aid in the reciprocal mechanism?
Peroneus tertius and Flexor digitorum superficialis
What is the direction of the peroneus tertius tendon?
Cranial to tibia
What is the direction of the flexor digitorum superficialis?
Caudal to tibia
When is the stifle fully locked?
When horse takes most of weight on that limb and rests on toe of the hoof
What occurs when stifle is locked?
Weight of hindquarters tends to flex hock
Opposed by tension in superficial flexor caudal to tibia
Peroneus tertius superfluous in animal standing quietly
In the passive stay apparatus of pelvic limb where does the caudal mass of the trunk rest on?
Head of femur
What does the center of mass cause caudal to the stifle if unsupported?
flexion
What does the center of mass cause cranial to the hock if unsupported?
flexion
What does the center of mass cause crainal to the fetlock if unsupported?
extension
