MT I Flashcards
Definition of a lame horse:
Structural or functional disorder in one or more limbs and related structures.
Anatomical landmarks/location of lameness
- Hoof, navicular bone
- Tendons, ligaments
- Tendon sheat, bursae
Explain the reciprocal apparatus
Stifle is always moving together with the hock. So if you flex the stifle the hock will be flexed as well, as the fetlock & the digits work together.
Peroneus Tertius/fibularis tertius on the front attached from the extensor fossa of femur and insert in 3rd tarsal bone
What are the Phases of the strides
1. Supporting phase
- Landing
- Loading
- Stance
1. Breakover Phase
- Heel lift
- Toe pivot
1. Swinging phase
Which phase of the stride is this?
Break over phase
* Extension: Fetlock
* Hyperextension: DIPJ (Distal interphalangeal joint)
Which phase of the stride is this?
Stance phase
Hyperextension: Fetlock
Flexion: DIPJ
Which phase of the stride is this?
Breake over phase
Which phase of the stride is this?
**Stance phase
**
Which phase of the stride is this?
Swinging phase
- Flexion (Caudal)
- Extension (Cranial)
What is shown on the picture
Abnormal Joint Hyperextension
What is shown on the picture
Constant DIPJ Hyperextesion
Explain the different Interference forms at the trot
A. Front limb to front limb
B. Ipsilateral front to hind
C. Pacer (Diagonal limbs)
D. Ipsilateral hind to front
Explain the different feet movement from a skyline view
Normal – padding – winging – plaiting
What could be potential causes for Lameness
- Trauma
- Congenital (Ex. Navicular disease)
- Acquired
- Infection
- Metabolic disturbances
- Circulatory disorders (Aortoiliac Thrombosis)
- Nervous system
- Pain
- Mechanical
- Paralytic disorders
Lameness due to infection
* If foal is lame (No injury) Nr 1 reason is?
* Treatment?
* Nr 1 reason is –> Joint Infection
* * Hematogen origin, swollen joint, fetlock – stifle. Effusion of infected site, think first of all joint.
* If infection do not give steroids but AB intraarticular.
Lameness due to metabolic disorders
* Example
* What to do?
- Laminitis
- Endotoxemia
What to do with this:
* Make **abaxial perineural block **
* Check pulsation – if laminitis hard pulsation
Lameness due to circulatory disorders
- Example
- Signs?
- How to Diagnose?
* Aortoiliac Thrombosis
- Beginning light lameness on left – sweat and colic symptoms.
- Worsening during training, shows great pain
- Saphenous vein (Dors.med. aspect of heart) Less arterial blood supply, less backflow so the veins are empty.
- **One leg is warm, while the other is cold **
Diagnose with Ultrasonography.
Lameness due to the nervous system
* Example
*
- Sweeney:
-
Suprascapular Neuropathy. When horse walk to you, horse flexing shoulder against abaxial direction.
* Atrophy of supraspinatus and infraspinatus muscle (Colateral ligament) - Can have a hit from anything and damage to the peripheral nerve but able to regenerate itself.
What are the different degree of lameness
**1 – 5 **or 1 – 10 (Europe) 0 - 5 (AAEP)
* Grade I: Very mild
* Grade II: Mild
* Grade III: Moderate
* Grade IV: Severe
* Grade V: Non – Weight bearing
How to distinguish the Character of the lameness
- Unchanging (Warming up)
-
Changing =
* Improving during training/examination (must probably be Chronic Osteoarthritis)
* Intermittent (Few steps, very lame and walk again)
How to classify the lamenes
Classification of lameness
* Supporting limb lameness
* Swinging limb lameness
* Compensatory lameness
* Untypical lameness
* Special lameness
How to recognize supporting limb lameness
- Phase of the stide
- Head and neck movement
- Where to localize the pain
- What happens to the fetlock?
- What happens to the cranial phase of the stride in relation to supporting or swinging phase lameness?
Cranial phase is longer
* More pain during contraction
* Will quickly shift weight to the other side.
Head and neck movement:
* Head and neck **elevation on the affected side.*
The problem is usually lower
Worse in inside circle
IMPORTAINT:
Lameness in when viewing from front:
1. Head and neck elevated
2. Hyperextension in fetlock during stans
3. **Cranial phase of the stride **
* Longer when supporting lameness
* Shorter when swinging phase lameness
How to recognize swinging limb lameness
- Cranial phase is shortened
- It is evident during motion
- Usually the problem is higher
- Worse in outside circle
How to recognize compensatory lameness?
- Uneven distribution of weight on another limb
- Lame FL –> Other FL
- Navicular diesase –> Sole bruise
How to recognize Untypical lameness
- When more than one limb is effected
How to recognize special lameness
Example
Diagnosis
Picture
- Ex:** rupture of peroneus tertius**
-
Upward fixation of the patella
* DDFT rupture –> Take sonography
*** Chronic navicularis syndrom **
Picture: Achilles tendon to loose –> Stifle is in full extension : The whole reciprocal apparatus is destroyed. Fibularis tertius and peroneus tertius ruptured. Yearling – Preform x – ray from stifle
Patella fixation
* Type of abnormality
* What to do surgically
* How to lock the patella
* How to improve without surgery
Fibrotic Myopathy
- Last movement of swinging phase –> Dropping the leg back again, due to semimembranosus and semitendinosus myopathy
- Can see a groove, do not forget to palpate.
Steps of the lameness examination
Anamnesis in lameness examination
- How long has the horse been lame?
- What is the cause of the lameness?
- How did it happen?
- Has been rested or exercised?
- Previous treatment, what was the result?
- When was the horse shod?
Can get aseptic inflammation around the chorion –> test the nails
Hoof abcess. - Is he still in work?
- Does he warm out of the lameness?
What can be seen
Osteoarthrithis in distal Interphalangeal joint.
- Swelling around coronary bone = ring bone
What can be seen
Ancleosis: Joint fuse and become one structure.
What can be seen
Bone sparring on hock
LAMENESS
Visual examination
At a distance and close examination
Distance:
- Conformation
- Body condition
- Positure
- Atrophy, asymmetry
Close:
- Hoof
- Swelling, distension
LAMENESS
Visual examination
What are you able to preform in the practice
- Anamnesis
- Visual examination
- Palpation
- Provocation test
- Diagnostic anaesthesia
Visual examination
- At a distance (All directions)
- At rest
- At exercise
- What are you able to preform in the practice
Lameness
Supplementary diagnostic aids
- RTG
- Arthroscopy
- MRI
- UltraSound
- Synovia analysis
- CT
What is shown on the picture
Provocating tests
(flexion)
What is the purpose of diagnostic analgesia
- Find site of pain causing lameness
- Confirm suspected site of pain
Diagnostic analgesia
What is the reason of failure?
- Bad technique
- Variation of peripheral nerve anatomy
- Local anaesthetic diffuses proximally
- 70 – 80% positivity is a positive result
- Deep bony pain is difficult to anaesthetize
- You cannot block out all intraarticular pain.
- Mechanical lameness.
Diagnostic analgesia
What local anaesthetics should we use?
Less irritant:
* Mepivacaine,
* Prilocaine,
* Bupivacaine
More irritant:
* Lidocaine
Diagnostic analgesia
Effect of duration
Fast acting (2h DOA)
* Mepivacaine
* Prilocaine
Slower acting (4h DOA)
* Bupivacaine
Diagnostic analgesia and restrain
- Depends on horse
- Minimal restraint is less stressful
- Good handler is essential
- Position yourself safely
Physical:
o Twitch
Sedation
o Small doses
o Xyalzine (0.1 – 0.2 mg/BWT)
o Detomidine (0.005mg/Bwt) –> Safer, affect result in higher doses.
Leg position (On ground, held by clinician, held by assistant)
Diagnostic analgesia
Patient preparation
- Perineural analgesia
o Clean procedure (Clip if hairy)
o** Antiseptic scrub** until clean
(Povidone iodine, chlorhexidine)
o Alcohol with swab then spray.
Diagnostic analgesia
Patient preparation
- Intrasynovial analgesia
o Aseptic procedure
o Clip
o 5 minute antiseptic scrub
o Alcohol wash
o Sterile gloves
o Fresh bottle anaesthetic
Diagnostic analgesic procedure
1. Size needle
2. Quantity of analgesia
3. Time for evaluation
4. Intra synovial analgesia
5. Post block
1.** 18 – 25 gauge needles** (Use fine needles when possible) –> Length depends on size
2. Quantity of anaesthetic depends on site
3. Evaluate
o 5–10minutes
o 20 – 30 minutes
o 60 minutes
4. Intrasynovial analgesia
o Usually acts more quickly
o** Shorter duration**
** 5. Post block
**o Sterile wrap (5 . 10 min)
Diagnostic analgesia
– fore limb strategy
NO clinical suspicion as to site of pain
- Block from** distal to proximal**
- Use regional blocks
- Differentiate with intrasynovial blocks later if necessary.
Perineural analgesia blocks – FORELIMB
Deep digital nerve anaesthesia
1. Size needle
2. Quantity
3. Anatomical landmark
4. Structure anaesthetised
- 23G 1.5 needle
- 1.5 ml anaesthetic
- At level of collateral cartilage
Structures anaesthetised:
o Palmar foot
o Toe
o DIP joint
o +/- distal DDFT lesions
o Part of P2 and joint
Perineural analgesia blocks – FORELIMB
Positive low or prox palm digit analgesia
Differentiate structures with:
- DIP
- Navicular bursa block
- PIP block
Perineural analgesia blocks – FORELIMB
3. Abaxial Sesamoid Block
1. Anatomical landmark
2. Size of needle
3. Quantity
4. Used in case of
5. Structures anaesthetised
Anatomical land mark 2.
Size of needle
Quantity
- At level of prox. Sesamoid bone:
- **22–23G ** —> 1.5cm needle
- 3ml local anaesthetic
- Use this block if laminitis. Nervovascular bundle surrounded by tubular facsia –> Do not have a stable type anaesthesi. Set the block parallel to the nerve not straight in it.
- Structures anaesthetised
* As for PDB (Proximal pastern)
* Sometimes include –> Fetlock joint (MCP) & Sesamoid bone locally.
* Block** distal DDFT lesions**
At level of distal aspect of prox sesamoid bone
* **26G **–> 1.5 cm needle
* 1.5ml of local anaesthetics.
Interarticular analgesia blocks – FORELIMB
4. Distal interphalangeal joint analgesia
Procedure
Size needle
Quantity
Anaesthetised structures
- Aseptic procedure
- 19 G - 3cm needle
- 6ml anaesthetic
-
DIP joint, dorsal sole (toe)
-** 10 ml anaestetics –> Block heel as well**
Interarticular analgesia blocks – FORELIMB
5. Navicular bursa analgesia
Procedure
Size needle
Quantity
Anaesthetised structures
- Aseptic procedure
- Radiographic control
- 19 G 7cm needle
- 3.5ml anaesthetic
- 0.5ml iohexol contrast solution
- Structures anaesthetised
o Navicular bursa
o Dorsal sole (toe)
o Navicular bone
o Navicular ligaments (Not heel)
o 30 minutes: DIP joint
Perineural analgesia – FORELIMB
6. Proximal interphalangeal joint (PIPJ)
Doral approach
- 21 G 2.5cm needle
- 5ml anaesthetic
Palmar approach
- 21 G 2.5cm needle
- 5ml anaesthetics
Structures anaesthetised
- Pip joint
Perineural analgesia – FORELIMB
7. 4 point block (N. digit.palm.,nn. Metacarpales)
- 23 G 1.5 cm needle
- 1.5 – 3ml anaesthetic
- Palmar nerves (lat.med)
- Palmar metacarpal nerves
Perineural analgesia – FORELIMB
8. Positive 4 point block
Differentiate structures with:
o MCP analgesia
o Digital sheath analgesia
Perineural analgesia – FORELIMB
9. Metacarpophalangeal joint anesthesia
Structures anaesthetised
- MCP joint
- Subchondral bone pain –> slow to respond
- 30min may anaesthetize;
- Dist. Suspensory branches + sesamoids
- Dorsal and palmar approaches
o 19–22G 3-4cm needle
o 10ml anaesthetic
Perineural analgesia – FORELIMB
9. Metacarpophalangeal joint anesthesia
Dorsal approach
o Easier
o Articular cartilage easily traumatised
Perineural analgesia – FORELIMB
9. Metacarpophalangeal joint anesthesia
Palmar approach
- Between suspensory ligament and MC3
- Sometimes difficult to be sure of centesis
Perineural analgesia – FORELIMB
10. Digital flexor tendon sheath (DFTS) analgesia
Proximal approach
- 20G 2.5cm needle
- 10 – 15ml anaesthetic
Perineural analgesia – FORELIMB
10. Digital flexor tendon sheath (DFTS) analgesia
Distal Palmar approach
- 20G 2.5cm needle
- 10 – 15ml anaesthetic
Perineural analgesia – FORELIMB
11. High palmar block
- 20G 3cm needle
- 5ml in each side
- Palmar nerves
Perineural analgesia – FORELIMB
12. Subcarpal block
- Supf + DDF tendon anesth.
- Structures anaesthetised
o Whole metacarpal region
o 65% chance of penetrating carpometacarpal (CMC) joint
o Dorsal branches must be anaesthetised
to block the skin dorsally
Perineural analgesia – FORELIMB
13. Lateral palmar analgesia
- Spesific for suspensory ligament lesions
- 22G 1.5cm needle
- 5ml anaesthetic
- less chance of blocking the CMC joint
Perineural analgesia – FORELIMB
14. Suspensory ligament origin infiltration
- Spesific for suspensory ligament lesions
- 19G 5cm needle
- 10ml anaesthetics
- From lateral
- Include palmar metacarpal nerves
Perineural analgesia – FORELIMB
**15. Postive subcarpal analgesia
**
- Perform middle carpal joint analgesia
- Can diffuse around palmar nerves
And block metacarpal structures
Perineural analgesia – FORELIMB
16. Middle carpal and antebrachiocarpal analgesia
- Dorsal pouches
- Medial or lateral
- 19G 3cm needle
- 5ml anaesthetic
- Check in 5 – 20 minutes
- Remember: Subcarpal analgesia and middle carpal joint analgesia may block the same structures
- Clinical findings may help to differentiate
Perineural analgesia – FORELIMB
17. N. Ulnaris analgesia
- 18G 4cm needle
- 10 – 15ml anaesthetic
- 10cm prox from accessory carpal bone
Perineural analgesia – FORELIMB
18. N. Medianus analgesia
- 5cm below elbow joint, medial side
- Caudomedial surface of radius
- Just cranial from m.flex. carpi radialis
- 10ml local anaesthetic
- Arteria and vein located caudally form it
- False positive response because of elbow joint
Perineural analgesia – FORELIMB
N. Musculocutaneous anaesthesia
- Branch for skin
- Seldom necessary
-
4x3ml
o V. Cephalica cran.caud .
o V. Cephalica. Access.cran. caud
Perineural analgesia – FORELIMB
20. Elbow anaesthesia
- Cranial + caudal pouch
- 19G 9cm needle
- 25ml anaesthetic
- NB radial nerve
Cran approach: Signs of radial paresis
Method: Infront of collateral ligament 2/3 distance between humerus epicondyle and tub. Radii in cranial direction
Caud approach: Method: Infront of olecranon caud form epicondyle long needle, may need skin local anaesthesia
Perineural analgesia – FORELIMB
21. Shoulder joint anaesthesia
- 19G 9cm needle
- 25ml anaesthetic
- Wait 30 minutes
- Inbetween tub majus pars cran et caud humeri
- Infront of infraspinatus insertion
Perineural analgesia – FORELIMB
22. Bicipital bursa anaesthesia
- 19G 9cm needle
- 20ml local anaesthetic
- Puncture under ultrasonographic control adviced
- 4cm distal and 6-7 cm caudal from tub.majus pars cranialis humeri
Nerve blocks hindlimb
1. Plantar digital block
- Same as in forelimb
Nerve blocks hindlimb
2. Pastern ring block
- Include dorsal branches
- And dorsal metatarsal nerves
- Blocks pastern and foot
Nerve blocks hindlimb
3. Low plantar six point
- Plantar digital nerve
-
Plantar metatarsal nerve
o Important for subchondral bone of distal MCIII -
Dorsal metatarsal nerve
o Deep peroneal nerve, N. Saphenous + supf peroneus nerve - Blocks all tissues distal to block
- Positive (return later to block)
o Fetlock
o Digital sheath.
Nerve blocks hindlimb
4. Subtarsal (high plantar)
- Now less frequent used,
- Instead Deep branch of lateral plantar nerve (LPN)
- Plantar and plantar metatarsal
- 5ml deep and supf 20G 4cm needle
- Blocks suspensory ligament
- Complete ring block to anaesthetise whole metatarsus
Nerve blocks hindlimb
5. Intra – articular Tarsometatarsal and Centrodistal
- Usually communicate
- Do TMT first plantolateral
- 21G,4cm needle
- 5–10ml
- Usually communicate
- Do TMT first from plantarolateral
Nerve blocks hindlimb
6. Intra – articular Tarsocrural joint
- 19G 4cm needle
- 10 – 15ml
- Dorsomedial: Axial to saphenous vein
- Communicates w/ prox. Intertarsal joint.
Nerve blocks hindlimb
8. Tibial and Peroneal
- Superficial and deep peroneal
- Hands breadth above point of hock
- Between long and lat dig ext muscles
- o 15ml 4cm deep
o 5ml under skin - TIBIAL
o 20ml 1cm deep
o From medial side
TIBIAL and PERONEAL
o May have medial and plantar superficial sensation
o Should eliminate sensation in foot and suspensory ligament o Blocks all tarsal structures
o May not achieve 100% resolution of lameness
Nerve blocks hindlimb
**9. Intra – articular Femoropatellar, medial and lateral Femorotibial*
- Femoropatellar joint
o Either side of middle patellar ligament
o Difficult to retrive synovial fluid
Nerve blocks hindlimb
**9. Intra – articular Femoropatellar, medial and lateral Femorotibial*
- Medial femorotibial
o Pouch cranial to medial collateral ligament o Fluid should be retrived
Nerve blocks hindlimb
10. Intra – articular coxofemoral
- 19G 20 cm needle
- 30ml anaestethic (Rarely preformed and difficult)
Nerve blocks hindlimb
11. Sacroilliac joint
- Be aware! Sciatic nerve ventral to the S/I joint
- Cranial gluteal nerve caudal margin ileal wing
- Medial approach preferred to avoid nerve
- Cranial to tuber sacrale
- Caudal to L6 dorsal spine
- From contralaterally
- Probably peri articular
- Usually block bilaterally
- 20 – 25cm needle
- 30 ml anaesthetic
- Can use ultrasound guidance
Type of injury
Traumatic injury of DDFT
Type of injury
SDFT injury
Tendons
Traumatic injuries
DDFT
Prognosis
Complete rupture, loss of function
- Deep digital flexor tendon (DDFT)
o Toe flips up (see photo above) - always the sign!
o If in the metacarpal/metatarsal region and outside the DFTS - can heal satisfactorily if immobilized
o If ruptured near the insertion/within the DFTS -very poor to hopeless prognosis
Tendons
Traumatic injuries
SDFT
Prognosis
Superficial digital flexor tendon (SDFT)
o **Reasonable prognosis if immobilized **
- Cast or Robert-Jones bandage
- Often transected together with DDFT
Type of injury
Suspensory ligament
Tendons
Traumatic injuries
Suspensory ligament
Prognosis
Suspensory ligament, often in racehorses
* Prox. sesamoid bone drops
* Fetlock drops
- Graveprognosis
- Degenerative/traumatic/catastrophic
Tendons
Traumatic injuries
Other traumatic injuries
-
Overreach injuries
o Pastern
o (Metacarpalregion) - Other physical trauma
- o From fence etc.
Boots/bandages won ́t prevent tendinitis/tendinopathy but can protect the limb from physical injuries
Site of injury
SDFT
Superficial digital flexor tendon
Sites of injury
Occurence in?
Most common site:
- Mid-metacarpal region
o Common injury in racehorses and jumpers
- Within the DFTS and the carpal sheath (proximally)
o Less common
- In the pastern region
o Often traumatic, overreach
Which injurie?
Injurie of SDFT due to over reach, injurie in the pastern region
