Investigation and Management of the Juvenile Lame Animal 1 Flashcards
What signalement is often associated with juvenile lameness?
- Generally less than one year old
- Breed predispositions, e.g. Rottweiler and medial coronoid disease, Border collie and shoulder OCD
- The cat rarely suffers from specific juvenile disease.
What history is often associated with juvenile lameness?
- Chronic- greater than two weeks duration
- Shifting lameness e.g. panosteitis
- Waxes and wanes?
- Worse on rising or after exercise?
- Associated with signs of systemic illness e.g. metaphyseal osteopathy
What should you focus on during your clinical exam investigating juvenile lameness?
- Forelimb or hind limb? On occasions this can be hard to determine and the client is often confused
- Is the condition confined to a single limb?
- Are there any joint swellings?
- Is there pain or heat in a joint or bone?
- Is there pain when palpating pads or twisting nails?
What is Perthe’s disease? What signalement and clinical history is usually associated? What clinical signs and radiographic findings are expected? How is it treated?
Avascular Necrosis of the Femoral Head
Signalment and clinical history
* The toy and small dog <6 months old.
* Inherited in the Manchester terrier
* A similar condition reported in the cat
* Lameness with associated muscle atrophy
* Reluctant to jump or go up and down stairs
* Bilateral in 12-16% of cases
Clinical signs
* Often marked muscle atrophy (particularly the gluteal muscles)
* Considerable pain on extension of the hips
* Crepitus on manipulation of hips
Radiographic findings
* Mottled appearance to femoral neck and head due to areas of lucency
* A misshapen and often triangular shape to femoral head
* Secondary osteoarthritic changes
* Loss of muscle mass
Conservative management
* NSAIDs, nutraceutricals etc
* Physiotherapy
* Rarely successful as these dogs walk well on three limbs and therefore avoid using the painful leg
Surgical management
* Femoral head and neck excision
* Total hip replacement (micro and nano systems:- Biomedrix)
What surgical technique is used for a fermoral head and neck ostectomy?
- Craniolateral approach is made to the hip with a tenotomy of deep gluteal and partial cut to vastus lateralis improve visualisation of the femoral neck
- It is essential that the cut removes all the femoral neck
- The dog has a degree of anteversion to the head and neck therefore the cut needs to take more of the caudal region of the neck than the cranial
- It is also important to leave the lesser trochanter intact (insertion of iliopsoas, a hip flexor)
What should always be done post femoral head and neck excision? What is the prognosis for dogs having undergone this because of Perthe’s disease?
- Post op radiographs should always be taken
- If not enough of the femoral neck has been resected further bone should be excised
Prognosis
* Small dogs can manage well on three legs therefore rehabilitation with analgesia, physio- and hydrotherapy are essential to encourage early use of the limb.
* It is important to appreciate that the limb is always shorter and the hip has reduced extension.
* The loss of limb length is compensated for by tilting of the pelvis
* Overall the prognosis for these dogs is good and in the well managed case the owner may be unable to recall which limb has undergone surgery
What clinical signs and history are associated to metaphyseal osteopathy? What clinical and radiographic signs can be expected? How is it treated? What is the prognosis?
Clinical history and signs
* Seen only in dogs (metaphyseal osteopathy in the cat does not seem to be the same condition)
* Unknown aetiology although there is a suggestion that this may be an immune mediated condition
* Less than 6 months old
* Severe and excruciating painful swelling to the metaphyseal region of all limbs
* Pyrexic and systemically unwell
Clinical signs
* Often unable to walk
* Pyrexic and inappetent
* Painful swellings to the distal limbs particularly the radius ulna and tibia
* Associated pitting oedema over the metaphyseal regions
Radiographic signs
* Soft tissue swelling
* Ill defined lucency parallel to the physis sometimes described as an extra growth plate
* Periosteal lifting with mineralisation
* The bridging of the physis by the inflammatory change can result in angular limb deformities
Treatment
* Hospitalisation
* Multi-modal analgesia including opiates and constant rate infusions
* Corticosteroids can be helpful in patients that fail to respond to symptomatic treatment
* Intravenous fluids
* Tube feeding if inappetent for longer than three days
Prognosis
* Good to fair
* These dogs are prone to further attacks and other autoimmune disease in later life
What are miscellaneous causes of lameness to consider in the juvenile?
- Early cruciate disease in larger breeds e.g. Mastiffs and Rottweilers
- Patella subluxations in large and small breed dogs
- Septic arthritis:- in the adult dog this is generally present in a single joint but can be multiple in the young animal. The elbow is the commonest joint for sepsis
- Polyarthritis:- multiple sterile arthropathy. Consider post vaccination in the dog and cat and in the cat can occur with calici virus infections
- Humeral intracondylar fissure in spaniels
- Sesamoid disease. Pin point pain over the flexor sesamoids
What clinical signs and signalment are often associated to craniomandibular osteopathy? What radiographic findings are expected? How is it treated? What is the prognosis?
Signalment and clinical signs
* Small terriers particularly the West Highland and Cairn
* Has been reported in larger dogs including the Dobermann
* Less then 6 months old
* A very painful condition of the mandible, skull and occasionally long bones
* Also known as Lion Jaw
* Soft tissue swelling and oedema to jaw and long bones
* Systemically unwell and pyrexic
* With chronicity becomes progressively difficult to open the mouth
Radiographic features
* Characteristic palisading (battlement-like) new bone to the mandible, occipital crest and tympanic bullae
* The temporomandibular joint may be involved
* Similar changes seen in the long bones
* Associated soft tissue swelling
Treatment
* Analgesia
* Corticosteroids are often required to manage this condition
* Fluid and enteral support
Prognosis
* This can be guarded as cases are difficult to manage and distressing for dog and owner
* Long term sequelae are not uncommon including reduced opening of the mouth making eating and subsequent endotracheal intubation difficult
What signalment and clinical history is often associated to panosteitis? What clinical signs and radiographic signs are expected? How is it treated? What is the prognosis?
Signalment and clinical history
* A common but often overlooked condition
* Seen in the young dog less than one year of age
* GSD and males are over represented
* Has a characteristic waxing and waning signs
* Often presents with a shifting lameness i.e. a lameness that spreads from one limb to another
Clinical signs
* Often the dog is depressed and can be pyrexic
* Lameness can be severe and the dog may not weight bear
* Pain on palpation of the diaphysis
* May have had a previous episode lasting about a week in another limb (a shifting lameness)
Radiographic signs
* Loss of normal trabecula pattern particularly around the nutrient foramen
* Endosteal and periosteal new bone
* Important to appreciate that radiographic and clinical signs may not occur and sometimes its better to radiograph two weeks after the signs have been seen
Treatment
* Rest and analgesia (NSAI)
* Advise the owner that this is an episodic condition usually lasting a week and is self limiting
Prognosis
* Excellent
* The episodes of acute lameness will become less severe and less frequent
* Most cases have resolved by the time the dog is 1 year old
* Occasional reports of the condition occurring in the 5 year old but this is very rare.
* Reassure the owner
What is rickets?
- This is a rare cause of lameness in the young growing animal
- It is associated with a absolute lack of vitamin D often compounded by reduced exposure to sunlight or a calcium/phosphorus imbalance
- There is pain and swelling around the physeal regions of the long bones and a reluctance to move
- The growth plates are widened due to poor or delayed mineralisation of the cartilage
- Treatment is by the provision of a balanced diet containing adequate amounts of vitamin D and exposure to sunlight
- A differential for this condition is nutritional secondary hyperparathyroidism in which poor skeletal mineralisation is due to a low calcium/high phosphorus, usually meat, diet.
- In this the bones have thin poorly mineralised cortices and are prone to pathological folding fractures and vertebral body collapse. Dietary correction, analgesia and restriction of exercise is all that is required to treat this condition.
What occurs in pituitary dwarfism?
- A rare condition
- A congenital hereditary abnormality caused by pituitary panhypopituitarism seen primarily in the German shepherd dog but occasionally seen in the spitz and Manchester terrier
- The pars distalis is affected and results in somatotropic, adrenotropic and thyroid stimulating hormone deficiencies
- Proportionate dwarfism and alopecia with hyperpigmentation reported.
- Physis remain open. No guard cells in the coat and small testes or absent oestrus cycles
- Treatment is with cortisol, thyroxine and progestogens
- Side effects of the medications are common and include pyometra, insulin resistance and mammary hyperplasia
- Life expectancy is reduced but these dogs can make good pets
What are angular limb deformities? What is their CORA?
- There are many types of these deformities. Those in the antebrachium are the most common (refer to Prof White’s developmental lecture of last year)
- They occur in the young growing animal when one of two or part of a growth plate closes prematurely
- This arises from either trauma or bridging with periosteal bone (e.g. metaphyseal osteopathy)
- The lameness arises from joint pain due to abnormal stresses and associated subluxations
- The treatment employed depends upon whether there is any growth left in the affected limb
- Valgus is a lateral deviation of the distal limb. Varus is medial (remember valgus contains an “l” for lateral)
Centre of rotation of angulation (CORA)
* This is an important concept when correcting limb deformities.
* It determines the place when any definitive correction should be performed
* Correcting the angular deformity away from this centre results in an S shaped bone and poorer function
What forelimb bones can be affected by angular limb deformities? How are these corrected?
Antebrachrachium
Short ulna
* This is the most common abnormality
* Due to the conical shape of the distal ulna growth plate this is more prone to trauma and premature closure
* It results in a valgus deformity, cranial bowing of the radius and external rotation of the paw
* In some cases in which there is no valgus deformity only elbow incongruity the short ulna can be managed by an osteotomy which releases its bow string effect.
* This technique is prone to long healing times and occasionally non unions
* Immature dog:- staple the medial radial growth plate to correct the disparate growth rates. Timing of this is difficult and this correction is rarely performed
* Mature dog:- easier to perform any correction at this time
* calculate the CORA
* osteotomy of the ulna to release the bowstring
* opening wedge osteotomy of the radius fixed with ESF or Ilizarov circular fixator which facilitates limb lengthening
* or a closing wedge osteotomy of the radius fixed with custom bone plate and applied with the use of a jig (3D printing particularly useful for these abnormalities)
Short radius
* Premature closure of the distal radius
* Results in subluxation of the radiohumeral joint
* Corrective radial closing wedge ostectomy with ulna ostectomy
* Fixation achieved with T plate and K wire
* Ulna ostectomy is unlikely to heal but allows the correction of the carpal valgus with the radial ostectomy and realigning the limb
What hindlimb bones can be affected by angular limb deformities? How are they corrected?
- These abnormalities are much less common
- Same principles apply
Pes varus can be treated with distal osteotomy and opening wedge stabilised with ESF
Tarsal valgus treated with closing wedge ostectomy and plate fixation
* A wedge of bone is resected
* The deficit is closed and plate applied
* This can be aided by the use of 3D models with printing methods using the CT images
What recent advancement has made the correction of angular deformities easier?
- CT is used to produce models of the limb and a jig
- The jig allows accurate cutting of the bone to correct the angulation and to guide placement of the screws in a custom plate
- This has made the correction of such abnormalities both more accurate and easier for the surgeon
