Musculoskeletal Flashcards
What are the five type of Salter-Harris fractures?
What is the primary goal for open fracture management?
Control acute infection to prevent osteomyelitis
Describe Gustilo–Anderson open fracture classification scheme
If the fracture involves growth plate, it should be ideally repaired within how many days?
3 days
What are the 6 indications for open reduction after traumatic joint luxation
1) Joint reluxation
2) Closed reduction failed
3) Chronic luxation
4) Concurrent intra-articular fracture
5) Internal stabilization is needed for adjacent long bone fractures
6) Suspect neurological injury and exploration is warranted
Describe how to perform closed reduction for cranio-dorsal hip luxation?
1) Place patient in lateral recumbency with the luxated hip on top
2) Place a rope or towel roll in the groin of the affected limb, wrap it around over the back and pull it opposite to the toes to create resistance
3) Grab the affected limb with one hand at the tarsus and one hand at the greater trochanter
4) Externally rotate the limb, and pull it distally to position the femoral head over the acetabulum.
5) Once femoral head is next to the acetabulum, internally rotate the limb to seat the femoral head into the acetabulum
6) Apply medial pressure to the greater trochanter while flexing and extending the hip joint to push out any blood clot in the acetabulum for 10-15 minutes
7) Place the limb in an Ehmer sling
Describe how to perform close reduction for ventral hip luxation
1) Place patient in lateral recumbency with the luxated hip on top
2) Grab the affected limb with one hand at the tarsus and the other hand at the femoral body. Keep the limb perpendicular to the spine.
3) Place traction on the limb while simultaneously abducting the leg to pull the femoral head beyond the medial rim of acetabulum
4) Once femoral head crosses the medial rim of acetabulum, push proximally to facilitate the femoral head to fall in the acetabulum
5) Apply pressure to the hip joint to push out any debris or blood clot in the acetabulum for 10-15 min.
5) Place hobbles
Describe how to place an Ehmer sling.
1) Apply cotton padding on the plantar metatarsal surface of the foot.
2) Use roll gauze or adhesive tape to cover the cotton padding (roll from medial to lateral).
3) Pull the bandage material from the lateral aspect of the metatarsus to the medial aspect of flexed stifle
4) Bring the bandage material over the cranial aspect of the thigh
5) Bring the bandage material from the medial aspect of the tibia and the to the lateral aspect of the metatarsus in a figure-of-8 pattern. Make sure the hock joint is flexed
6) Make sure the hip joint is internally rotated.
7) Repeat the bandage pattern to apply additional layers
7) The bandage can incorporate the caudal abdomen
What the the hallmark for secondary bone healing (indirect bone healing)?
Callus formation
What are the five phases for secondary bone healing?
1) Inflammation
2) Intramembranous ossification
3) Soft callus formation (chondrogenesis)
4) Hard callus formation (Endochondral Ossification)
5) Bone remodeling
What are the four important steps for open fracture management?
1) Proper wound debridement
2) Copious tissue irrigation/lavage
3) Prompt administration of broad spectrum antibiotics
4) Restoration of soft tissue coverage to healing bone, tendon, ligament and nerves tissues.
What is the purpose for Ehmer slings in dogs with craniodorsal hip luxation?
To prevent external rotation of the femur which increases the risk of reluxation
Describe how to place a Modified Robert-Jones bandage
1) Stirrups are taped at the medial and lateral side of the limb. The free ends are taped on a tongue pressor stick to prevent them from sticking together.
2) Apply 3-5 layers of cast padding or rolled cotton from the distal end of the limb to the proximal end (above the joint proximal to the fracture/wound). Make sure there is at least 50% overlap with each round.
3) Apply 2 layers of rolled gauzes from the distal to proximal of the limbs.
4) Twist the stirrups in 180 degree and tape to the outside of the gauzes
5) Apply self-adhesive tape or Vetwrap to the limb (from distal to proximal)
What are the general rules for circumferential layers during bandaging?
1) The material should be applied in even tension and avoid wrinkles
2) Each new wrap overlaps the previous wrap by 50%
3) Each layer should continue the entire length of the bandage
4) The last layer should end proximally (avoid an encircling tourniquet effect)
What is the four mechanisms of the penrose drain?
1) Capillary action
2) Overflow
3) Gravity
4) fluctuation of pressure within the space occupied by the drain
What are the three main factors determining the successful management of osteomyelitis?
1) Viability and stability of the bones
2) Virulence and antimicrobial susceptibility of the organisms
3) Condition of the soft tissue envelope
What are the top three most common bacteria identified in osteomyelitis in dogs and cats?
1) Staphylococcus spp
2) E. coli
3) Streptococcus spp
What is the most common cause for osteomyelitis in dogs and cats?
Post-traumatic/direct inoculation
Describe the pathogenesis of osteomyelitis
1) Inflammatory cytokines affect the normal osteoclasts & osteoblasts activity
2) Bone ischemia
3) Provide a ideal environment for microbial organisms because antimicrobials and inflammatory cells cannot reach the avascular area
Which part of the long bone does the hematogenous osteomyelitis most commonly seen?
Metaphyseal region
What is the current gold standard to diagnose post-traumatic osteomyelitis?
Microbial culture
What are the two main categories of osteomyelitis?
Post-traumatic/direct inoculation
Hematogenous
What are the Six treatment aspects for post-traumatic osteomyelitis?
1) Drainage
2) Debridement
3) Microbial culture & sensitivity
4) Delayed closure
5) Remove the implant if the fractures heal
6) Adequate antimicrobial therapy with proper duration
How long does the patient with post-traumatic osteomyelitis usually need to be on antimicrobial therapy for?
4-6 weeks
if patient has implants in place, 8 weeks
usually for the first 3-5 days, IV antimicrobial therapy is recommended
Describe two methods to diagnose craniodorsal hip luxation.
1) Put the thumb at the ischiatic notch (between the greater trochanter and ischiatic tuberosity) and externally rotate the femur. If the hip joint is in place, the thumb should be pushed away from the ischiatic notch.
2) Palpate the ischiatic tuberosity and cranial dorsal of the iliac spine. Palpate the greater tuberosity. If the hip joint is in place, the greater tuberosity should be below the imaginary line drawn between the ischiatic tuberosity and cranial dorsal of iliac spine.
List four different open reduction options for hip luxation.
1) capsulorraphy (or other type of joint capsule repair)
2) Toggle-rod fixation
3) Femoral head and neck ostectomy
4) Total hip replacement
Which breed is at high risk of developing hypertrophic osteodystrophy (HOD)?
Weimaraners
What is the common age for HOD?
2-6 months
What is the hallmark of radiograph findings for HOD (Hypertrophic Osteodystrophy)?
A lucent line in the metaphysis parallel to an increased radiodensity zone immediately adjacent to the physis.
What is the general prognosis for HOD?
good and usually self-limiting
What is the proposed cause of panosteitis (i.e. eosinophilic panosteitis, shifting leg lameness)?
Vascular congestion
Increased intraosseous pressure
(Protein accumulation?)
What are the three most common affected long bones for panosteitis?
Ulna
Radius
Humerus
What is the most common age for panosteitis
5-12 months old
What is panosteitis?
Self-limiting inflammatory disease of the bone marrow of long bones
What is Legg-Calvé-Perthes Disease also called?
Avascular necrosis of the femoral head
What is the common signalment for Legg-Calvé-Perthes Disease (size, age)?
Small breed dogs
4-11 months old
What is the main clinical findings of hypertrophic osteopathy?
deposition of periosteal new bone
What is the average age for hypertrophic osteopathy?
Adult dog
What is the common concurrent findings with hypertrophic osteopathy?
Primary or metastatic pulmonary neoplasia
Describe iliopsoas muscle maneuver test.
1) Flex the hip joint
2) simultaneous internally rotate and extend the hip joint
What is the diagnostic test for masticatory muscle myositis?
Autoantibodies for masticatory muscle type 2M fibers
If you need to do a muscle biopsy for the diagnosis of MMM, which muscle should you obtain the biopsy from?
Temporalis muscle
** DO NOT USE frontalis muscle → false negative result
What is the treatment for MMM?
Prednisone 2 mg/kg/d
What are the classification of IMPA? Give 3 examples for each classification.
Primary (erosive vs non-erosive)
Systemic Lupus Erythematosus
Breed predisposed (e.g. Greyhound erosive IMPA)
Idiopathic IMPA
Infectious
Tick-borne disease
Leishmaniasis
Bacterial arthritis
Non-joint neoplastic
Reactive
Drug-reactive
Vaccine-reactive
Distant infection
For arthocentesis, what is the minimal number of locations/samples required?
4
For synovial fluid cytology, what is the cutoff number to differentiate immune-mediated & infectious vs degenerative?
> 10% Neutrophils → immune-mediated & infectious
What are the three most common joints for septic arthritis?
1) stifle
2) elbow
3) carpus
What is the most common and second most common causes for septic arthritis?
1) post-op infection from articular surgery
2) hematogenous
True or False: The gold standard for the diagnosis of septic arthritis is synovial fluid culture.
False
Only a minority of cases yield positive result.
What are the three diagnostic criteria for bacterial infective arthritis?
1) Typical history & clinical signs
2) Synovial fluid cytology consistent with bacterial infective arthritis
3) Positive bacterial culture
What is the recommended antimicrobial treatment for bacterial infective arthritis?
at least 28 days
- The author of the Vet Surgery Textbook recommends continue antibiotics until the cell counts return to normal and neutrophils percentage < 3%
What is the treatment for idiopathic IMPA?
Prednisone 1-2 mg/kg/d
or Prednisone 1 mg/kg/d + Mycophenolate 10 mg/kg q12h
*Duration: at least 4 months
What is the normal total protein level and cell counts in synovial effusion?
TP: < 2.5 g/dL
cell count: < 3000 cells/uL
What are common findings for septic synovial effusion?
High cellular count (5000-10000+++ cells/uL), TP > 2.5 g/dL with degenerative neutrophils predominant
Describe how to perform a joint tap on a carpal joint.
1) Use 22 to 25G needle with 3ml syringe.
2) Clip and aseptically prepare the medial aspect of the carpal joint while the animal is sedated and in lateral recumbency
3) Partially flex the carpal joint and identify the distal margin of radius
4) Insert the needle into the radiocarpal joint from the anteriomedial area. Once the needle enters skin, gently pull the plunger back to create a mild negative pressure.
5) Slowly insert the needle until the synovial fluid is obtained.
6) Release the negative pressure before pulling the needle out
Describe how to perform a joint tap on a hock joint.
1) Use 22 to 25G needle with 3ml syringe
2) Clip and aseptically prepare the lateral aspect of the hock joint while the animal is sedated and in lateral recumbency
3) Partially flex the hock joint and palpate the lateral malleolus of the fibula
4) Insert the needle distal to the lateral malleolus of the fibula.
5) Once the needle enters the skin, slowly shift the skin caudally.
6) Advance the needle to enter the joint lateral and distal to the lateral malleolus of the fibula.
There are two peaks in terms of the age for osteosarcoma. When are they?
18-24 months old
> 10 yrs
What are the two most common site for osteosarcoma in dogs?
Distal metaphysis of the radius
Proximal metaphysis of the humerus
Describe the blood supply to the nasal cavity in dogs
External carotid artery → maxillary a., facial a.,
Internal carotid artery → internal ethmoidal a., external ethmoidal a.
