2. - diagnostic aid used to localize lameness
when the site of pain is uncertain.
- surgical procedures can performed without
the need for general anesthesia.
- provide temporary, humane relief of pain.
4. Palmar Digital Nerve Block
- “heel block”, PDN
- most commonly used
- needle is inserted
directly above the
neurovascular bundle of
the foot.
5. Semi-ring Block at the
Pastern
- anesthetize the dorsal
branches of the digital
nerve that supply the
foot.
- above the collateral
cartilages at the same
site as PDN block.
6. Abaxial Sesamoid Nerve Block
- local anesthetic solution is
deposited at the base of the
proximal sesamoid bones
over the neurovascular
bundle.
7. Low Palmar Nerve
Block (Low 4-Point Block)
- medial and lateral palmar
nerves are anesthetized.
- local anesthetic solution
is deposited SC at the
distal end of each splint
bone to complete the
block.
8. High Palmar Nerve Block
(High 4-Point Block)
- medial and lateral
palmar and palmar
metacarpal nerves are
anesthetized slightly
distal to the level of the
carpometacarpal joint.
11. ► Complete or partial rupture of a cruciate ligament
resulting in severe lameness and joint instability.
► Effusions of the femoropatellar or femorotibial joints
are sometimes present.
Diagnosis:
♣ Confirmed by arthroscopic examination through
Ultrasonography.
12. Treatments:
♣ Conservative treatment for acute injuries [rest, systemic
NSAID, and intra-articular corticosteroids].
♣ Arthroscopic surgery is recommended to debride loose and
torn ligament fibers.
♣ Lameness is usually improved by intra-articular anesthesia of
the femorotibial joints.
Prognosis:
♣ Complete rupture have a grave prognosis.
♣ Moderate to severe injuries have a poor prognosis for return
to athletic function.
♣ Mild injuries have a fair prognosis.
13. ► Rupture or sprain of the medial or lateral collateral
ligaments of the stifle usually as a result of an acute
traumatic episode in which the distal limb is forced
medially or laterally.
►Concurrent injury of the menisci or cruciate ligaments is
common, particularly in severe injuries.
14. Clinical Signs:
♣ Localized edema and joint effusion is seen, particularly
in the acute stages.
♣ Enthesiophyte formation at the origin or insertion of the
ligament may be evident radiographically in chronic
cases.
♣ If complete ligament rupture has occurred, stressed
caudocranial radiographs of the stifle may demonstrate
joint widening on the affected side. Signs sually improve
within a few days without any significant joint
instability.
15. Diagnosis:
♣ Confirmed by Ultrasonography.
Treatment:
♣ Mild sprains may be treated conservatively with stable
rest and anti-inflammatory medication for 6–8 weeks
followed by a controlled, ascending exercise
rehabilitation program for a further 6–8 weeks.
Prognosis:
♣ Horses with mild sprains and no joint instability have a
fair prognosis for return to athletic use.
♣ Severe injuries have a poor prognosis.
16. ► The medial patellar ligament remains hooked over the
medial trochlear ridge of the femur and locks the
reciprocal apparatus with the limb in extension.
► Horses with recurrent upward fixation or delayed
release of the patella may develop chronic, low-grade
lameness due to stifle soreness and may be reluctant to
work.
► Most commonly seen in young horses and
ponies, particularly if they are in poor body condition
and poorly muscled older horses that have had trauma
to the stifle region, especially if horses are stabled or
have been inactive.
► Straight hindlimb conformation may predispose to this
condition.
17. Diagnosis:
♣ Based on recognition of typical clinical signs.
♣ Radiography of the stifle should be taken in horses with
femoropatellar joint effusion and lameness to establish
concurrent or secondary pathology.
Management:
♣ To release an upward fixated patella, the horse should be
pushed backward while simultaneously pushing the
patella medially and distally. Alternatively, pulling the
limb forward with a rope around the pastern may unlock
the patella.
♣ Stable rest is contraindicated and the horse should be
turned out to pasture as much as possible.
18. ♣ If upward fixation of the patella is intermittent and not
causing lameness, a conditioning program should be
instituted. This involves daily lungeing or riding of the
horse, appropriate to its age and type, as well as
ensuring an adequate plane of nutrition, good
dentistry, and anthelmintic administration.
♣ Remedial hoof trimming to ensure that the foot is well
balanced and shoeing with a bevel-edged shoe with or
without a lateral heel wedge may be beneficial.
♣ A significant proportion of horses will improve with
maturity and conservative treatment although signs
may recur if the horse undergoes prolonged stall rest.
19. Treatments:
♣ Conservative treatment
♣ Medial patellar ligament desmotomy is indicated in
horses that fail to respond to conservative treatment
or in horses with lameness caused by upward
fixation of the patella.
“Medial patellar ligament desmotomy is most often
performed in the sedated horse under local
anesthesia or general anesthesia. Following
surgery, the horse should be restricted to stable or
small pen rest for 2 months to reduce the risk of
complications”
20. Complicatios:
♣ Fragmentation of the apex of the patella
♣ Lameness
♣ Local swelling
♣ Patella fracture
Prognosis:
♣ Generally considered to be good with rare
recurrence of the condition.
21. ► Usually occurs secondary to medial patellar
desmotomy for the management of upward fixation
of the patella.
► Lesions are believed to occur due to patellar
instability as a result of the surgery.
► A proximal limb flexion test usually exacerbates
lameness and femoropatellar joint effusion is
usually present. Lameness is localized by diagnostic
anesthesia of the femoropatellar joint.
22. Diagnosis:
♣ Confirmed by radiography.
Treatment:
♣ Arthroscopic debridement of the apex of the patella
and removal of the osteochondral fragments is the
treatment of choice.
Prognosis:
♣ Reasonable but depends on the severity of the
condition
23. ► Displacement or misalignment 0f the patella.
► Lateral luxation of the patella is a rare, inherited condition in
foals caused by a recessive gene.
► Luxation of the patella in adult horses is unusual and likely to be
traumatic in origin. Lateral luxation is more common than
medial luxation and may be more likely in horses or foals with
hypoplasia of the lateral trochlear ridge of the femur.
► The condition may be unilateral or bilateral and varies in
severity from intermittent luxation [that readily reduces] to
persistent luxation [that cannot be reduced].
► Severely affected foals are unable to extend the stifle and adopt a
characteristic crouching position.
► If the condition is less severe, foals or horses may be reluctant to
flex the stifle and demonstrate a stiff hindlimb gait.
24. Diagnosis
♣ Confirmed by radiography.
Treatment:
♣ Surgery
Prognosis:
♣ The prognosis in adult horses and horses with
concurrent osteoarthritis is poor.
♣ The prognosis for athletic function in foals may be
slightly better.
25. ► Usually rare but may be seen in jumping horses.
► The middle patellar ligament is the most commonly
affected.
► Lameness is variable but may be severe in acute
cases.
Clinical signs:
♣ Femoropatellar joint effusion
♣ Periligamentous thickening
♣ Edema
27. ►Gonitis is a term indicating inflammation within the stifle
joint.
► Mild to moderate inflammation of the femorotibial and
femoropatellar joints of unknown origin.
► Synovitis and capsulitis may result from athletic sprain of
the joints.
Management:
♣ Mild synovitis usually responds to rest.
♣ Intra-articular and systemic anti-inflammatory drugs.
28. ► Osteoarthritis is a disease of joints with multifactorial
causes that results in the progressive degradation and
destruction of articular cartilage.
► Osteoarthritis of the femorotibial or femoropatellar
joints may follow any of the causes of stifle lameness
described and usually results in persistent lameness of
varying severity.
Diagnosis:
♣ Confirmed with intra-articular anesthesia and
radiography.
29. Lesions/Radiologic changes:
♣ Periarticular remodeling with osteophyte formation and
remodeling of the joint margins (particularly the medial
tibial plateau)
♣ Changes in the subchondral bone
♣ Narrowing of the joint space
♣ Dystrophic mineralization of the soft tissues
30. Prognosis:
♣ Prognosis for athletic soundness in horses with
osteoarthritis of the stifle is poor.
Treatment:
♣ Usually palliative.
♣ Newer techniques for arthroscopy and regenerative
therapy may offer some hope for severely affected joints.
31. FRACTURES OF THE PATELLA
► Fractures of the patella usually result from direct
trauma
►Fracture of the patella usually results in marked
lameness initially, with swelling and edema over the
patella and effusion of the femoropatellar joint.
In less severe or nonarticular fractures, lameness may
improve within a few days.
32. Diagnosis:
♣ Confirmed by radiography.
Management:
♣ Conservative treatment with stable rest for 6-8
weeks for horses with
small, nondisplaced, nonarticular fractures . Good
prognosis for return to athletic function.
♣ Articular fractures can be removed arthroscopically
or via an arthrotomy. Good prognosis.
♣ Larger mid-body sagittal or horizontal fractures
require repair by internal fixation.
33. FRACTURES OF THE TIBIAL TUBEROSITY
► Usually result from direct trauma of the little soft tissue
covering this joint.
► Usually results in marked lameness initially with
localized swelling and edema.
Diagnosis :
♣ Confirmed by radiography.
34. Treatments:
♣ Conservative treatment with stable rest for 6–8 weeks.
♣ Larger, intra-articular fractures should be repaired by
internal fixation.
Prognosis:
♣ Fractures generally have a good prognosis for return to
athletic function if appropriately managed.
35. FRACTURES OF THE FEMORAL CONDYLES AND
FEMORAL TROCHLEAR RIDGES
►Usually the result of direct trauma.
► Large, intra-articular, displaced fractures in adult
horses are atastrophic and have a grave prognosis.
►Usually result in acute onset, moderate to severe
lameness with joint effusion.
36. Diagnosis:
♣ Confirmed by radiography.
Treatment:
♣ Surgery [arthroscopically and/or arthrotomy].
Prognosis :
♣ Good as there is no significant concurrent soft tissue
damage.
37. ► Most cases are traumatic in origin, secondary to falls or
being cast (within a stall) in recumbency, although
septic arthropathies and developmental disorders of the
joint have been occasionally reported.
► Results to osteoarthritis of the coxofemoral joint and
lameness.
Clinical Signs:
♣ Lameness
♣ Pain on proximal limb flexion or abduction.
♣ In some cases of acute fracture, a hematoma or
alteration in the bony architecture are palpable per
rectum.
39. ► Relatively rare and is usually secondary to trauma.
► Much more common in small ponies and has been
frequently described secondary to upward fixation of the
patella.
► Fracture of the dorsal acetabular rim may accompany
the dislocation and is usually accompanied by a
characteristic alteration in limb appearance.
40. Management:
♣ Closed reduction under general anesthesia, although this
is only likely to be successful if the reduction is
performed soon after the injury.
♣ The prognosis for return to athletic function following
coxofemoral luxation is very guarded.
41. ► Major cause of poor performance and gait abnormalities
in sport and race horses.
►Once back pain is suspected or established in a
horse, identification of the cause requires imaging
procedures.
42. KISSING SPINES
► location of these lesions is the vertebral segment
between T10 and T18 or L1 and L6.
► Abnormal findings can be easily seen in the dorsal and
ventral part of the spinous processes.
► They include kissing and overriding lesions.
Different Grades
♣ Grade 1: Narrowing of the interspinal space
♣ Grade 2: Densification of the margins
♣ Grade 3: Bone lysis adjacent to the margins
♣ Grade 4: Severe remodeling.
43. ► Commonly found in racing Thoroughbreds and are rare
in Standardbreds.
Diagnosis:
♣ Aided by injection of local anesthetic into the affected
interspinous spaces.
Management:
♣ Local injections of steroids
♣ Mesotherapy, and/or shockwave therapy
♣ Rehabilitation
44. FRACTURES
► Mostly seen in spinous processes of T4–T10 and are
sometimes seen in horses that have reared and fallen
over backward.
► The summits and centers of ossification are fractured
and displaced laterally.
► Recovery is often satisfactory after the pain has
subsided.
► No permanent effect on performance, but a persistent
deformation of the withers may require use of a special
saddle.
45. DESMOPATHIES (Supraspinal ligament injuries)
► Acute or subacute desmopathies induce dorsoventral or
transverse thickening of the ligament, reduced
echogenicity, and severe alteration of the linear pattern
found in the median plane or asymmetrically.
► Alteration of the bone surface of the top of the spinous
processes indicates insertional desmopathy
(enthesopathy) of the supraspinous ligament.
46. ► located dorsally to the vertebral canal and is composed
of the caudal articular process of one vertebra, the
synovial joint located at the base of the interspinal
space, and the cranial articular process of the following
vertebra.
► Abnormal radiographic findings were mainly observed
at the thoracolumbar junction and in the lumbar area.
► AP-SIVA lesions are much more likely to be associated
with back pain than kissing spines or any other vertebral
lesions.
47. ► Vertebral Spondylosis - most common lesion of
vertebral bodies and disks.
- mainly found in the midthoracic
area [mostly between T10 and T14] but can also be
observed in the lumbar area.
► Congenital abnormalities with vertebral body
deformation (triangular or trapezoidal shape) are rare
and usually found in the thoracic vertebrae.
48. ► Vertebral body osteomyelitis can be seen in the
thoracolumbar spine in foals.
► Complete or partial paraplegia results from damage to
the spinal cord.
Prognosis:
♣ The prognosis is grave.
49. ► Commonly caused by damage to the muscles acts to
extend and laterally flex the vertebral column.
Clinical Signs:
♣ Altered performance
♣ Back pain
Treatments:
♣ Conservative treatment, rest and physiotherapy
50. Congenital abnormalities: lumbosacral ankylosis or
intervertebral ankylosis
Disk degenerative lesions - fissuration or cavitation of the
disk, dystrophic mineralization and ventral herniation
Intervertebral malalignment (spondylolisthesis)
Intertransverse lumbosacral osteoarthrosis
Diagnosis:
♣ Ultrasonography
51. ► Acute and severe strain of the sacroiliac ligaments is
associated with a history of injury and of severe pain in
the pelvic or sacro-iliac region marked hindlimb
lameness.
► Subacute or chronic sacroiliac strain and osteoarthrosis
of the sacroiliac joint cause typical back soreness.
Diagnosis :
♣ Physical examination
♣ Ultrasonography
52. Abnormal Ultrasonographic Findings
♣ Bone modeling of the sacrum and/or ileum
♣ Narrowing of the joint space
♣ Remodeling or periarticular osteophytes of the caudal
border of the auricular surface of the sacrum
♣ Remodeling or periarticular osteophytes of the caudal
auricular margin of the ileum
♣ Periarticular bone fragmentation
♣ Ventral sacroiliac ligament desmopathy and
enthesopathy.
53. Treatment and Management:
♣ Ultrasonographic-guided injections of steroids
♣ Mesotherapy over the painful area
♣ Rehabilitation using progressive warmup at a slow
canter and exercises that develop the gluteal muscles.
54. ► Acute or chronic Inflammation of a tendon with varying
degrees of tendon fibril disruption.
► Most common in horses used at fast work [racehorses].
► Seen in the flexor tendons and is more common in the
forelimb than in the hindlimb.
Lesions:
♣ Central rupture of tendon fibers with associated
hemorrhage and edema.
55. Etiology:
♣ Usually appears after fast exercise and is associated with
overextension and poor conditioning, fatigue, poor
racetrack conditions, and persistent training when
inflammatory problems in the tendon already exist.
Predisposing Factors
♣ Improper shoeing
♣ Poor conformation
♣ Poor training
56. Clinical Findings :
♣ Acute stage: Severe lameness, involved structures are
hot, painful, and swollen.
♣ Chronic stages: Fibrosis with thickening and adhesions
in the peritendinous area. The horse may go sound while
walking or trotting, but lameness may recur under hard
work.
Diagnosis:
♣ Ultrasonography
57. Treatment:
♣ Stall-resting
♣ Swelling and inflammation treated with cold packs and
systemic anti-inflammatory agents.
♣ Tendon splitting has been recommended when a distinct
hypoechoic or anechoic core lesion is present.
♣ Shock wave therapy, intralesional injection of fat-derived
stromal cells or cultured bone marrow-derived
mesenchymal stem cells, or autologous conditioned
plasma.
♣ Superior check ligament desmotomy - adjunctive
treatment to minimize recurrence
58. Chronic tendinitis
♣ Superficial point firing and percutaneous tendon
splitting.
♣ Annular ligament desmotomy is also used when
tendinitis involves the area of the digital tendon sheath.
Prognosis for a flat-racing Thoroughbred racehorse to
return to racing after a bowed tendon is guarded.
Contraindication:
♣ Intratendinous corticosteroid injections
60. ♣ One of the most important and prevalent developmental orthopedic diseases of horses.
Osteochondrosis is currently used to describe the clinical manifestation of the disorder.
Dyschondroplasia is preferred when referring to early lesions because primary lesions are seen in
cartilage.
Etiology:
♣ Multifactorial and specific etiology is unknown.
♣ Osteochondrosis multifactorial etiology that includes rapid growth, overnutrition, mineral
imbalance, and biomechanics, genetics.
♣ The condition mainly affects articular growth cartilage, but the metaphysis may also be involved. If
the physeal metaphyseal cartilage is affected, bone contours and longitudinal growth are
disturbed (see Physitis in Horses).
Lesions:
♣ Changes at the joint margins, dissecting lesions, and the formation of cartilage flaps or
osteochondral fragments (osteochondrosis).
♣ Central articular lesions may lead to the development of subchondral cysts.
♣ Axial skeletal involvement includes vertebral articular facets.
61. Clinical Findings:
♣ Nonpainful distention of an affected joint.
♣ Lameness is more often the first sign observed.
♣ Often the first sign noted in foals is a tendency to spend
more time lying down accompanied frequently by joint
swelling, stiffness, and difficulty keeping up with other
animals, upright conformation of the limbs.
62. Diagnosis:
♣ Based on signalment and signs
♣ Radiographic examination
♣ Ultrasonographic examination
♣ Arthroscopy - most accurate
♣ Scintigraphy - has limitations in growing horses
♣ MRI - ideal for diagnosis of both early and late lesions
♣ Clinical pathology and the evaluation of synovial fluid rarely helpful
63. Treatment and Management:
♣ Conservative treatment
♣ Intra-articular medication with hyaluronic acid and
injection of long-acting corticosteroids but is NOT
recommended in young, growing horses.
♣ Arthroscopy
Prognosis
♣ Prognosis following removal of discrete osteochondral
fragments is good.
♣ Prognosis is poor for cases with instability resulting from
joint surface loss or in which secondary osteo-arthritis
(degenerative joint disease).
♣ Prognosis in cases involving subchondral cysts have is
guarded
64. ► Swelling around the growth plates of certain long bones
in young horses and can be a component of
osteochondrosis.
► Caused by malnutrition, conformational defects, faulty
hoof growth, excessive exercise, obesity, and toxicosis.
► Result of overload of the physeal area due to excessive
loading or weakened bone and/or cartilage or a
combination of these factors.
► Characterized by flaring at the level of the growth plate,
giving a typical “boxy” appearance to the affected joints.
► Physeal cartilage appears crushed and thinned
microscopically.
65. Treatment:
♣ Reducing food intake
♣ Confining exercise to a yard or a large, well-ventilated
loose box with a soft surface
♣ Ensuring that the feet are carefully and frequently
trimmed
♣ Correcting the diet
Prevention:
♣ Older foal or yearling that is fat or heavy-topped should
be watched carefully for clinical signs for early
adjustments.
66. ► Associated with postural and foot
changes, lameness, and debility.
► May be congenital and therefore identified in newborn
foals or acquired at an older age.
► Caused by uterine malposition, teratogenic insults
(arthrogryposis), and genetic defects in newborn foals.
► Chronic pain arose from
physitis, osteochondrosis, degenerative joint
disease, pedal bone fracture, or soft-tissue wounds and
infection is the most common cause of acquired tendon
contracture.
► The horse walks on its toes or knuckles in the fetlocks or
occasionally the pastern joint.
67. Clinical Findings:
♣ Unable to stand
♣ Attempt to walk on the dorsum of their fetlocks
♣ Can stand but knuckle in the fetlocks or carpi
♣ Animals may walk around on their toes with their heels
off the ground.
♣ Slower onset is characterized by a “boxy” hoof with an
elongated heel and concave toe.
♣ Physitis frequently is evident
♣ Toe abscesses are a frequent complication of the hoof
♣ Locomotion changes
68. Treatment and Management:
♣ Mild cases in newborn foals often require no treatment.
♣ More severe cases require supportive therapy
♣ Use of splints necessitates careful fitting and
management
♣ Casts are generally safer if used only for short periods
(5–7 days)
♣ High-dose oxytetracycline therapy is commonly used
(40–60 mg/kg).
69. ♣ Conservative management in early cases in older foals
and weanlings through nutritional correction, proper
hoof trimming, and analgesia.
♣ Desmotomy of the accessory ligament of the deep digital
flexor tendon (inferior check desmotomy) is the most
successful and commonly used procedure for flexural
deformity of the distal limb
♣ Superior check ligament desmotomy may be included for
horses with fetlock deformities.
70. ♣ For carpal deformities, sectioning of the
tendons of insertion onto the ulnaris lateralis
and flexor carpi ulnaris is performed.
♣ In hindlimbs, tenotomy of the medial head of
the deep digital flexor is performed
♣ In severe cases, tenotomy of the deep digital
flexor tendon can be used as a salvage
procedure.
♣ Nutritional correction, proper foot
trimming, and analgesia are integral to
recovery
74. ► The visual representation of an object, such
as a body part or celestial body, for the
purpose of medical diagnosis or data
collection using any of a variety of usually
computerized techniques.
75. ► Provide important pathologic and
physiologic information necessary to treat
specific conditions. Imaging can be divided
into anatomic and physiologic methods.
► Imaging may also help prevent injury
through early detection of the physiologic
changes associated with injury.
77. RADIOLOGY
► Most commonly used to evaluate lameness in
horses.
► Goal of radiology is to examine the region
sufficiently to fully evaluate the anatomic
structure.
► Allows assessment of bony tissues and reflects
chronic changes.
► Contrast radiography provides information
about articular cartilage and surfaces
78. ► Pathologic diagnoses are usually made by
radiography in conjunction with clinical
examination.
►Advantages of CR include fewer retakes, a lower
radiation requirement, and postprocessing
techniques that eliminate contrast problems.
► Diagnostic films require preparation,
positioning, and production.
79. ► Preparation involves readying the object to be
radiographed and requires cleanliness and
removal of foreign materials.
► Positioning is critical. The object must
be evaluated from a sufficient number of angles
to insure adequate evaluation.
► The production of good radiographs requires
the correct exposure of the film.
80. ULTRASONOGRPAHY
► Can be used to assess any soft tissues.
► The area to be examined should be
evaluated in 2 planes 90° apart.
► Selection of a probe should take into
account the depth, contour, and location of
the tissue to be examined.
81. ► The deeper the tissue to be evaluated, the
lower the wavelength of the probe used; the
higher the wavelength, the greater the detail
that can be achieved.
► Examination of complex anatomic areas
requires a convex linear probe.
► Examination of the pelvic region internally
requires a rectal linear probe.
82. ► Most useful in the evaluation of tendons and
ligaments but can also be used to evaluate
muscle and cartilage.
► It is a good idea to compare the right and left
sides before making an ultrasonographic
diagnosis.
► Assessment of anatomic changes serves as the
basis for any pathologic diagnosis, as well as
being important in determining prognosis.
83. MRI
Two types of MRI available:
♣ Low-field magnets - some low-field scanners can
be used to examine the standing, sedated horse.
♣ High-field magnets - produce a stronger signal
and higher resolution pictures in a shorter time
and require the horse to be anesthetized
♣ MRI provides sliced images of the anatomic region
of interest -- axial (transverse), sagittal
(longitudinal), and dorsal planes
84. CT
► A technology that uses very small x-ray beams
from many different angles around the body
(called a slice) that are reconstructed by
computer to produce an image.
► The CT scanner provides the clearest images
possible of the limbs, joints, nasal
passages, skull, sinus cavities, and neck that
improve the clinician's ability to accurately
define and identify the extent of abnormalities
of these regions.
85. ► Provide images that reflect physiologic
processes and assess metabolism or
circulation.
Types/ Methods:
♣ Thermography
♣ Scintigraphy
86. THERMOGRPAHY
► The pictorial representation of the surface
temperature of an object.
► Noninvasive technique that measures
emitted heat and is useful for detecting
inflammatory changes that may contribute to
lameness.
87. SCINTIGRAPHY
► The production of two-dimensional images of
the distribution of radioactivity in tissues after
the internal administration of a
radiopharmaceutical imaging agent
► Polyphosphonate radiopharmaceuticals are
given IV and distribution is then measured by a
gamma camera.
► Scintigraphy is useful for detecting lesions in
bone and ligaments.