SA Lameness and Investigation of Orthopaedic Disease

Question 1

In what apart of the bone is bone disease seen most commonly?
- why?

Answer 1

Metaphysis. - area of higher turnover.

Question 2

Plan of lameness investigation/examination.

Answer 2

Signalment and presenting complaint.
Hx.
Gait examination.
Physical exam.
Differential diagnosis and diagnostic plan.
Ancillary aids to diagnosis.

Question 2

Signalment flags of orthopaedic disease.

Answer 2

Young labrador w/ forelimb lameness = elbow dysplasia.
Older rotteweiler w/ forelimb lameness = arthritis/bone tumour.
Young MN cat w/ hindlimb lameness = fracture of femoral head.

Question 3

History taking for the lame patient.

Answer 3

Meds given?
Duration of lameness?
Onset?
Progression?
Lameness continuous/ intermittent?
Effect of exercise / rest?
Effect of ground surface?
Which limb(s)?
Occupation of dog?
Concurrent problems?
Cat-specific questions for cats?

Question 4

How may bone tumours present?

Answer 4

May present progressively lame or insidiously as the tumour grows.
May present acutely lame due to pathological fracture caused by the bone tumour.

Question 5

Lameness examination?

Answer 5

Stance:
- symmetry.
- Weight bearing.
- Angular deformity/curvatures.

Question 6

Term for foot out-turned laterally.
Term for foot in-turned medially.

Answer 6

Valgus.
Varus.

Question 7

Gait evaluation.

Answer 7

Gait at walk.
If not obvious, evaluate at trot, stairs, circles.
Can be done in consult or ask owner to send a video in.
- can be watched normal speed or slow mo.
Stride length.
Head nodding (when assessing FL lameness).
- sinks on the sound side.
Scuffing of nails.
Ataxia, paraparesis, paraplegia.
- suggestive of neuro?

Question 8

Lameness grading (0-10).

Answer 8

0 - sound.
1 - occasional weight shift.
2 - mild lameness at slow trot, none whilst walking.
3 - mild lameness whilst walking.
4 - obvious lameness whilst walking, places foot when standing.
5-8 - Degrees of severity.
9 - places toe when standing, carries limb when trotting.
10 - unable to weight bear.

Question 9

Full CE.

Answer 9

To identify concurrent diseases.
In cases where the patient has returned home lame and the cause in unknown.
- any other more urgent trauma.

Question 10

Ortho PE.

Answer 10

Palpate the standing animal for:
- asymmetry.
- swelling.
- muscle atrophy – neuro or lack of use.
- joint enlargement.
- abnormal conformation.
Joints:
- Swelling, joint effusion.
- Pain.
- Instability.
- Range of motion.
- Manipulation – any crepitus?
Limbs:
- swelling.
- muscle atrophy.
- pain.

Question 11

Neuro exam.

Answer 11

Palpate spine:
- neck and lumbosacral joint.
Screening neuro exam:
- conscious proprioception.
- spinal reflexes – (patella, withdrawal and perineal reflexes).
If abnormalities detected, perform full neuro exam.

Question 12

Cranial draw test.

Answer 12

Test of integrity of the cranial ligament.
- lateral recumbency.
- hold femur and tibia and try to move tibia cranially with respect to the femur.
- repeat test with stifle at different angles or flexion / extension.

Question 13

Tibial compression test (tibial thrust test).

Answer 13

A test of cranial cruciate ligament integrity.
- hand over distal femur first finger on tibial tuberosity, other hand on the foot.
- keep stifle still whilst flexing hock.
- tibial tuberosity displaces cranially if ligament ruptured.

Question 14

Patella luxation testing.

Answer 14

Stifle extended - quadriceps muscle relaxed.
Try and shift patella medially and laterally.
Patella difficult to locate in very small dogs - work proximally from tibial tuberosity.

Question 15

Ortolani test.

Answer 15

Test for hip laxity.
- dorsal recumbency.
- subluxate hips by pressing towards back.
- abduct femurs – click as hip reduces –> angle of reduction.
- adduct hips – click as hip reluxated –> angle of subluxation.

Question 16

Ortho differential diagnosis list mnemonics.

Answer 16

Bones - GIFT:
– Growth plates.
– Inflammatory / infectious / immune.
– Fractures.
– Tumours.
Joints - DIM:
– Dislocation –> congenital and traumatic.
– Inflammation –> OCD / OA / infectious.
– Musculotendinous and ligamentous (instability).

Question 17

Ancillary aids to diagnosis.

Answer 17

Diagnostic imaging:
- ultrasound.
- radiology.
- CT.
- MRI.
Arthrocentesis.
EMG.

Question 18

For what joint is CT favoured over x-rays?

Answer 18

Elbow - superimposition on x-ray.
Skull.

Question 19

MRI for ortho patient.

Answer 19

Useful for soft tissue architecture.
Less useful for bone.
Very useful for neurology / nerve root tumours.

Question 20

Ultrasound for ortho patients.

Answer 20

Good for evaluating soft tissue structures.
E.g. biceps tendon.
Relatively inexpensive compared to MRI.
Can be used to guide a biopsy.

Question 21

Palpating joint effusions.

Answer 21

Carpus - loss of definition of carpal bones cranially.
Elbow - bulge between the olecranon and lateral epicondyle.
Shoulder and hip - effusions not palpable.
Hock - palpable as a bulge cranially and caudally.
Stifle - bulges out either side of patella ligament.

Question 22

Arthrocentesis procedure.

Answer 22

5ml syringe and 23G / 21G needle.
Clip and aseptic preparation.
Introduce needle and apply negative with needle held still.
Release pressure before withdrawing needle from joint.
Make smear and submit EDTA sample.