Approach to lameness
- Hip dysplasia
- Osteochondrosis
- (Patellar luxation)
- (Cranial cruciate ligament disease)
- Other causes
- – Metaphyseal osteopathy
- – Nutritional secondary hyperparathyroidism
Approach to the lame dog
- What are you trying to achieve?
– Why is the dog lame? Dx
– Txt & prognosis
- How are you going to get there?
- History
– Onset (acute or chronic, inciting cause?), duration, progression, previous lameness, response to any previous tx, general health
– History and signalment guide you towards diagnosis
Approach to the lame dog
General physical examination
Orthopaedic examination
- Systematic
- Lameness (yes, no, maybe), severity, which leg(s)
- Muscle atrophy
- Joint effusions, fibrosis, range of motion, crepitus, instability, PAIN
- Bone pain
- Neurological abnormalities
- Findings guide you towards diagnosis and focus further investigation
Hip dysplasia
- Developmental disease
- Laxity and secondary osteoarthritis
– Both cause pain and lameness
– Laxity source of pain in immature dog, OA in adult dog (combination)
Aetiology – genetic and environmental factors
How does a dog with hip dysplasia present?
- Often characteristic gait – swings pelvis from side-to-side
- Lameness may be uni or bilateral
- Difficulty rising
- Audible click / clunk
- Poor muscle mass of hindlimbs
Are there characteristic orthopaedic exam findings?
- Pain on hip extension
Hip dysplasia How are you going to confirm the diagnosis?
1. Radiography under sedation
- Ventrodorsal extended
- Lateral
2. Palpation under sedation
- The Ortolani test
BVA/KC Hip Scoring Scheme
Hip dysplasia diagnosis – beyond the basics
- Orthopedic Foundation for Animals hip grading system (www.offa.org)
- Has recently been compared to PennHip:
TX;
- Conservative management
– Usually considered first
- Surgery
– Reduce degree of hip laxity – pelvic osteotomy or pubic symphysiodesis
– Salvage procedures – joint excision or prosthesis
What do you need to know?
- Good understanding of conservative management
- Awareness of surgical options and when they are appropriate
Conservative management
- Bodyweight and body condition
- Non-steroidal anti-inflammatory drugs
- Low impact exercise / physiotherapy
- Neutraceuticals / alternative therapies
- Beneficial to maintain slender body condition
- Bodyweight and body condition
– Reduces lameness in dogs with HD and OA
– Reduces development of HD in genotypically predisposed dogs
- Non-steroidal anti-inflammatory drugs
- Many different ones out there
- E.g. meloxicam, carprofen, firocoxib
- Differences in COX selectivity
- Good evidence to support efficacy
- Mainstay of osteoarthritis treatment in dogs
- Possible side effects – gastrointestinal, renal
- Low impact exercise / physiotherapy
- For example swimming
- Not much evidence other than opinion to support this
- Still worth discussing with owners / adding to treatment plan
- Polysulfated glycosaminoglycans (PSGAG)
- Semisynthetic product structurally similar to GAG
- Stimulate collagen synthesis, inhibit breakdown in vitro
- Some (limited) evidence to support improvement in lameness in dogs with HD and OA
- Diets
- Omega 3 fatty acid (fish oil) supplemented foods (e.g. Hills® J/D)
- Increasing tissue levels of omega 3 FA decreases levels of omega 6 FA and overall effect is to suppress inflammation
- Evidence supports use of these diets in dogs with OA, including hip OA
- Acupuncture
- Neutraceuticals / alternative therapies
Surgical options – decreasing joint laxity
1. Triple pelvic osteotomy
- Not for everyone- generally less than 1yr old
- They have a positive Ortolani sign
- With no radiographically obvious secondary OA
- Hip OA will still progress post operatively
- Performed in puppies 12-20 weeks old
- W/ radiographic abnormalities not CS
- Premature closure of pubic symphysis induced by electrocautery
- Usually combined with neutering procedure
- Not well established in UK
- Juvenile pubic symphysiodesis
Surgical options – salvage
- Femoral head and neck ostectomy
- Eliminates contact between femoral head and acetabulum = ↓discomfort
- Pseudoarthrosis (false joint) forms
- Limb function should improve but will probably never be normal
- Better results in smaller dogs
- Consider as “plan C” for hip dysplasia i.e if all else fails and dog is not a candidate for THR
– Aim for complete removal of head and neck
- Performed through craniolateral approach
- Straightforward surgery
- Useful technique for other conditions e.g. Perthes’ disease, hip luxation salvage – in practice
- Total hip replacement
- Replacement of diseased hip with prosthesis
- Better function than FHNO, best option for large breed dogs
- Much more technically demanding procedure
- Much more expensive
- Risk of significant complications
- Good outcome if all goes well
- Cemented and cementless systems available
- Micro systems available for toy dogs and cats
- Potential complications include luxation, infection and fracture
- Referral procedure
Osteochondrosis dissecans in the hindlimb
– Young dog.
- Disorder of endochondral ossification
- Affects articular cartilage surface
- Dissecans describes formation of a cartilage flap
- Secondary osteoarthritis will develop
- Stifle – femoral condyles (lateral usually)
- Tarsus – trochlear ridges of talus (medial usually)
- Hip – uncommon but can affect femoral head
Presentation
- Lame young (4-8 months) large breed dog
- Affected joint is effused and painful
- Radiographically look for defect in articular surface
TX;
1. Conservative management – most appropriate where OA is already advanced
2. Removal of cartilage flap by arthrotomy or arthroscopy
– Removes source of inflammation and discomfort
– Defect heals by fibrocartilage formation
– Clinical outcome better for some joints than others
3. Osteochondral grafts are now being explored
- Cores of cartilage and bone harvested from non-weightbearing regions
- Implanted in OCD defect
- Cartilage and bone become integrated in new location
- Initial results encouraging
patellar luxation in large breed dogs
- Why is the patella luxating?
- Tibial or femoral deformity?
- Need to correct deformity
- Referral situation
Cranial cruciate ligament disease
- Increasingly common in skeletally immature dogs
- Treatment options may be more limited
- Useful to be able to differentiate “puppy” from pathological cranial drawer- Puppy drawer has a distinct “end point”