Investigation & management of the mature lame animal Flashcards
General considerations in approaching the mature lame small animal - signalment
Elbow dysplasia
- labs, rotties, Bernese mountain dogs, Newfies
HIF
- spaniels
Infraspinatus contracture
- spaniels
Lateral patella luxation
- flat coat retrievers
Medial patella luxation
- many small breeds including Frenchies & occasionally labs and English bull terrier
Lumbosacral dz
- GSD
Neoplasia
- large and giant breeds
Cellulitis
- outdoor, unneutered male cat
General considerations in approaching the mature lame small animal - History clues (acute lameness, chronic lameness, intermittent, acute on chronic)
Acute lameness
- sprains
- acute cruciate rupture
- fractures both pathological and traumatic
- cellulitis
Chronic lameness
- OA
- humeral intracondylar fissure
- nerve root tumour
Intermittent
- patella luxation
- dislocation of the tendon of origin of the long digital extensor
- superficial digital flexor instability
Acute on chronic
- cruciate rupture
- pathological fracture
- condylar fissure subsequent to HIF
General considerations in approaching the mature lame small animal - clinical exam
- reduced or increased ROM and swelling to joints
- instability to joints or associated sesamoids e.g. patella
- pain and crepitus on manipulation of joints
- pain or crepitus on palpation of the long bones and joints or soft tissues
- muscle atrophy
- neuro deficits
General considerations in approaching the mature lame small animal - further investigations
Radiography
- mainstay of investigations of the lame small animal
CT
- esp of the elbow and shoulder
MRI
- spine, nerve roots, stifles and shoulder
Joint taps
- detection of septic arthritis and polyarthritides
Cruciate disease - prevalence & signalment
- extremely common dz
- not exaggerated to say any dog with hindlimb lameness has cruciate dz until proven otherwise
- is occasionally seen in the overweight cat or as part of a more severe stifle disruption
Patella subluxation - prevalence & signalment
- common condition
- less frequently seen in the cat (traumatic but also developmental in Abyssinian and Devon Rex)
- often asymptomatic
- common in small breeds e.g. Yorkies, poodles, frenchies, CKCS
- also seen in English bulldogs and labs
- lateral patella subluxation reported in the flat coated retriever (much less common than medial patella subluxation)
Shoulder soft tissue conditions - what happens and why?
The shoulder is innately unstable and relies on soft tissues for stability
- muscles: supra-, infra and subscapularis and teres minor
- tendons: biceps tendon of origin
- ligaments: medial and lateral glenohumeral
As a result of this it is prone to sprains, particularly the medial glenohumeral ligament and other soft tissue injuries.
The biceps tendon can become inflamed or rupture -> bicipital tendonitis.
A specific condition seen in working dogs is infraspinatus contracture.
Shoulder soft tissue conditions - diagnosis
Shoulder palpation
- any pain elicited?
Biceps tendon test
- apply pressure to the bicipital groove whilst retracting the shoulder and extending the elbow
- is there any pain elicited by this?
- is it possible to extend the elbow greater on 1 side?
– this is indicative of either biceps tendon rupture of avulsion (tearing of the tendon from its bony origin)
Manipulation under GA
- some debate as to how useful this test is
- the degree of abduction and adduction can be measured but is a little subjective
- greater adduction -> potential lateral glenohumeral ligament issue
- greater abduction -> potential medial glenohumeral ligament issue
Radiography
- mineralisation of the infra and supraspinatus tendons
- rely on CE for the significance of these findings
US
- particularly useful to examine the biceps tendon
- high frequency linear or hockey stick transducer is the appropriate probe
CT & MRI
- both can be useful
- CT requires contrast enhancement cf the elbow
Arthroscopy
- gold standard
- allows management as well as diagnosis
Shoulder soft tissue conditions - tx
- rest and NSAIDs are often beneficial but the time taken for any sprain to the collateral ligaments can be long
- the medial collateral is often the sprained ligament and it can be imbricated with sutures or lightly cauterised to induce scarring and stability, but neither tx appears effective
- tenosynovitis of the bicipital tendon can be treated with intra-articular corticosteroids or sectioning of the tendon which appears to make little difference in the dogs ability to walk
– this can be left or the tendon attached to the proximal humerus with a spiked washer and screw (tenodesis) - removal of mineralised parts of the tendons of insertion of the supra and infraspinatus muscles can occasionally improve any lameness but these are often incidental findings and therefor the significance of changes can be difficult to assess
Infraspinatus contracture - signalment & signs
- relatively rare condition
- seen primarily in working breeds e.g. springer spaniel
- a progressive condition
- characteristic limb position
– limb abducted, limp wrist posture
Infraspinatus contracture - tx & prognosis
- sectioning the tendon close to its insertion on the humerus
- can recur but generally prognosis is good
Humeral intracondylar fissure (FIC) - old name
- incomplete ossification of the humeral condyle (IOHC)
Humeral intracondylar fissure (FIC) - signalment
- spaniels including the Brittany, springer and CKCS
- common in the Frenchie but a recent study shows that when this condition is seen in the young dog they will go on to fuse when an adult
- young to middle aged dogs with no sex predilection
Humeral intracondylar fissure (FIC) - CS
- chronic forelimb lameness or acute if associated with lateral, medial or bicondylar fracture
- muscle atrophy and elbow swelling
- pain on manipulation of elbow and when pressure applied across condyle
- acute lameness associated with condylar fracture more often seen in the young puppy
– very common in Frenchie with minimal trauma e.g. jumping from sofa or O’s arms
Humeral intracondylar fissure (FIC) - diagnosis
Radiography
- multiple views required to be at right angles to the fissure in order to demonstrate the lesion
- sclerosis and thickening of the lateral supracondylar crest may also be seen
CT
- modality of choice
- may be a fissure or initially an area of sclerosis within the condyle
- contrary to initial assessment of these cases, this condition may not be a failure of the capitulum and trochlea of the condyle to fuse but 1 which can develop in the mature animal
- some recent studies suggest that it may be another manifestation of elbow incongruity resulting in the anconeus engaging on the caudal intercondylar region resulting in a stress fracture
Humeral intracondylar fissure (FIC) - tx
Conservative management
- rest and NSAIDS
- always a risk of condylar fracture which significant morbidity
Surgical management
1. placement of large transcondylar screw (4.5mm in most spaniels and labs)
- prone to significant number of complications
- breakage of the screw as the fissure rarely heals
- inadvertent penetration of the joint
- these can be minimised by placing the screw from medial to lateral (more difficult) and placing the screw as a lagged implant rather than positional (but the compression of the fracture site can lead to joint incongruence)
- CT produced templates can be used to aid screw placement
2. due to the suggestion that this condition can result from elbow incongruity a proximal ulna osteotomy has been used to bring about the healing of the HIF
- this technique has proven successful although it is not without its own complications although they’re less than those associated with a trans condylar screw
These fissures probably never heal hence the need for the strongest implant i.e. screw with the greatest core diameter
Carpal injuries - general considerations
- variable presentations but usually associated with varying degrees of lameness, instability and soft tissue swelling
- pain is not a consistent finding particularly in the chronic cases
Carpal injuries: hyperextension injuries - most common injury, signs, other causes
- most common carpal injury is that of hyperextension
- dog or cat jumps over a wall with a large drop the other side
- palmar ligaments and palmar cartilage are damaged irrevocably
- carpus is swollen with varying degrees of palmagrade stance (i.e. flat on their feet)
- can also occur as a result of destructive arthritis
Carpal injuries - diagnosis
Radiographs determine the level of the injury (stressed views helpful)
- antebrachiocarpal
- intercarpal
- carpometacarpal
This may not matter as generally a pan carpal arthrodesis is used to tx this condition
Carpal injuries - tx
- partial or pancarpal arthrodesis i.e. joint fusion as the ligaments will neither heal nor be capable of repair
- partial arthrodesis is rarely performed as it results in strain on adjacent joints
Carpal conditions: incomplete ossification of the radiocarpal bone - signalment & tx
- boxers and springer spaniels
- attempts to heal often fail as this is a similar pathology to HIF
- treat with pancarpal arthrodesis as healing of the bone very unlikely
Carpal conditions: stenosing tenosynovitis of the abductor polices longus - signalment & signs
- chronic lameness seen in exuberant dogs
- pain on carpal flexion
- soft tissue swelling medial carpus
- boney exostoses seen over the medial aspect of the radius in chronic cases
Carpal conditions: stenosing tenosynovitis of the abductor polices longus - diagnosis & tx
- US will demonstrate changes to tendon and increased fluid in the tendon sheath
- tx with steroid injection into the sheath, freeing the tendon or sectioning tendon (tenotomy) although the latter has been associated with marked degeneration of the carpus and is not recommended
Tarsal conditions: plantar ligament degeneration - signalment & signs
- collies, particularly Shetland sheepdogs
- insidious onset
- proximal inter tarsal subluxation with bilateral changes
- denigration progresses to rupture and plantigrade stance
Tarsal conditions: plantar ligament degeneration - diagnosis & tx
- clinical and radiographic diagnosis with proximal intertarsal subluxation
- treat with laterally applied plate and arthrodesis of the calcaneoquartal joint
- no further immobilisation required other than a support bandage for a week
Tarsal injuries in the racing greyhound
- rarely race again
- predominantly a right limb injury as in the UK these dogs race anti-clockwise and most force is generated by the RH
- combination of subluxations and fractures
- medial aspect of the joint collapses with fracture to central bone (several types with its own classification system)
- fractures and subluxations occur of the calcaneus and calcaneoquartal joint
- specialist injury requiring referrals
Tarsal conditions: gastrocnemius tendinopathy - signalment & signs
- older labs and Dobermans
- chronic hindlimb lameness
- often bilateral
- relatively common
- painful swelling to achilles tendon and mineralization on radiographs
- characteristic clawing of foot due to lengthening of gastroc but not the SDFT tendon
Tarsal conditions: gastrocnemius tendinopathy - tx
- resect tendon and place calcaneal tibial screw or transarticular external fixator to support the repair or a pantarsal arthrodesis
Open traumatic carpal and tarsal injuries - how do they occur and what to do?
- arise from trauma particularly and RTAs
- accompanied by varying degrees of soft tissue damage and contamination
- manage the soft tissue injuries 1st
- temporary external fixator may help in the initial stabilisation of the joint
- many of these injuries will require arthrodesis to manage
- other than the talocrural and antebrachiocarpal joints all others are low motion joints
- loss of low motion joints results in minimal loss of function
Hindlimb conditions: gracilis contracture - signalment, signs & tx
- mature GSD
- characteristic gait: short stride with a rapid, elastic medial rotation of the paw, internal rotation of the hock, and external rotation of the calcaneus
- progressive with no effective tx although some success reported with adipose tissue stem cells and laser tx
Hindlimb conditions: iliopsoas myopathy - signs, diagnosis & tx
Hindlimb conditions: long digital extensor avulsion - signalment, signs & tx
Hindlimb conditions: long digital extensor tendon luxation - cause & tx
Hindlimb conditions: avulsion of the gastrocnemius - signs & tx
Hindlimb conditions: superficial flexor luxation - signalment, signs, tx
