Ligaments, luxations, arthrodesis Flashcards

Question

Diagnosis of carpal hyperextension injuries

Answer 1

Survey radiographs may show soft tissue swelling, and avulsion fractures. In chronic injuries evidence of osteoarthritis may be present. Stressed radiographs are needed in most cases to determine the level of injury. Radiographs are taken with the carpus stressed in a hyperextended position. Compare with the opposite limb.

Answer 2

ntebrachiocarpal joint – least common middle carpal joint carpometacarpal joint - commonest

Answer 3

Arthrodesis - partial (fusion of middle carpal joint and carpometacarpal joint) - pan (fusion of all three joint levels)

Answer 4

Sometimes traumatic Also seen in Shetland sheepdogs with no history of trauma, often bilaterally

Answer 5

Tarsal arthrodesis - partial - pan

Answer 6

This is an uncommon condition seen only sporadically in Small breed dogs - toy poodles and shelties The luxation is commonly medial The condition may be bilateral.

Answer 7

Present with an abnormal gait when they are several months of age

Answer 8

Mediolateral and craniocaudal radiographs necessary to confirm In advanced cases the glenoid may be flattened or even convex in shape

Answer 9

In early cases attempts to reduce the luxation and place a small temporary transarticular pin may be successful. In more advanced cases then either arthrodesis or excision of part of the glenoid and part of the humeral head to allow a pseudoarthrosis to develop is generally successful. Some cases can be treated conservatively

Answer 10

Uncommon Campbells classification Surgical reduction is sometimes possible

Answer 11

Caudolateral dislocation of the radial head Probably developmental Most common in chondrodystrophic breeds First seen at 4-6months Usually premature closure of the distal ulna growth plate

Answer 12

Three options ○ osteotomy of the ulna, ○ ostectomy of the radius, ○ radial head excision. Sometimes deformity can be severe, osteotomys of both bones are required; and the prognosis is guarded.

Answer 13

Lateral dislocation of the ulna Congenital Recognised within several weeks of birth Lateral displacement results in an inability to extend the elbow

Answer 14

Reducing the ulna manually and placing a transarticular pin across the joint for 10 to 14 days, using pins and elastic bands to dynamically reduce the luxation. The prognosis is guarded for formation of a normal joint but function is usually adequate after treatment.

Answer 15

Dislocation of both radius and ulna laterally A more severe luxation and treatment is similar as for type II although the prognosis is more guarded

Answer 16

Usually occur after significant trauma Significant soft tissue damage has to occur to allow a joint to dislocate There will be ligament ruptures (collaterals) and in severe cases there may be muscle or tendon ruptures as well

Answer 17

Any Whippets may be over-represented

Answer 18

Fall, knock, dog fight, RTA

Answer 19

Often acute onset severe non weight bearing lameness

Answer 20

Limb carried in a flexed position, pain, and crepitation on manipulation

Answer 21

2 orthogonal x-ray views Check for concurrent trauma e.g. pneumothorax, fractures

Answer 22

Closed reduction or surgical reduction

Answer 23

dog anaesthetised attempt prior to surgery Lateral luxations: with leg extended apply medial pressure to humerus and lateral pressure to scapula, if reduction stable through a normal ROM then support with a spica splint for 10 -14 days. Medial luxations - reduce by extending leg and apply lateral pressure to the proximal humerus and medial pressure to the distal scapula, if reduction stable through a normal ROM then support with a velpeau sling for 10-14 days.

Answer 24

if closed reduction is unsuccessful then open reduction and stabilisation with capsulorrhaphy or tendon transposition is required In severe cases with dysplasia or DJD then salvage procedures such as glenoid excision or arthrodesis must be performed. A surgical approach is made to the joint and the articular surfaces are inspected. *If the labrum is worn then the prognosis for successful stabilisation is poor.

Answer 25

fair, DJD may develop.

Answer 26

Very rare Occurs secondary to severe trauma Disrupts the attachment of the scapula to the thoracic wall May be commoner in cats than dogs Relocated using a heavy gauge wire placed through a small hole in the caudal border of the scapula

Answer 27

Traumatic luxation of the elbow is not common. However when it occurs the direction of the luxation is usually lateral as the medial aspect of the condyle is larger and slopes distally making medial luxation very unlikely.

Answer 28

Often trauma e.g. RTA

Answer 29

Non-weight bearing lameness with adduction of the elbow, abduction of the foot and pronation of the foot Elbow swelling usually present and ROM severely limited

Answer 30

radiography (orthogonal views) check for the presence of fractures

Answer 31

Attempt closed reduction If closed reduction successful assess collateral ligament inetgrity If not successful then attempt surgical repair - primarily using a suture technique like the locking loop pattern

Answer 32

Leg should be supported in an extended position using either a bandage up to the axilla or preferably a body bandage or spica splint External coaptation should not be used for more than 2 weeks or severe stiffness of the elbow joint will result

Answer 33

after closed reduction alone the prognosis is good with 90% of dogs returning to normal. The prognosis is worse after surgical reduction (usually the chronic or more severe cases) with only 50% returning to normal and the other 50% staying intermittently or permanently lame.

Answer 34

These are elbow luxations that occur concurrent to fractures of the ulna. The annular ligament AND interosseous ligament may both be damaged. The ulna fracture must be repaired. Reluxation is a common complication secondary to the ligament instability. It is important to repair/replace the annular ligament or fixate the radius to the ulna (either temporarily or permanently) to minimise the likelihood of reluxation.

Answer 35

Hip luxations most commonly occur in a cranio-dorsal direction, ventral or caudal luxation is much less common. Medial luxation may occur in combination with an acetabular fracture.

Answer 36

Gait: affected animals will be non-weight bearing or markedly lame on the affected limb Thumb displacement test negative - the thumb will not be displaced if the hip is dislocated craniodorsally Radiography

Answer 37

animals should preferably be anaesthetised (or very heavily sedated). Reduction is achieved by extension of the hip followed by internal rotation of the hip. A palpable or audible click should be felt when the hip is reduced. Reduction should be confirmed with further radiography. Cage confinement or placement of an Ehmer sling should then be used to prevent reluxation.

Answer 38

Hip dysplasia Femoral head fracture fragments Blood clot, fibrous tissue, or infolding of the joint capsule in the acetabulum Inadequate restriction of exercise post reduction

Answer 39

Articular fractures are present The luxation is chronic There are other injuries present Closed reduction is unsuccessful The joint reluxates

Answer 40

(femoral head and neck excision or total hip replacement) should be considered if there is underlying hip dysplasia.

Answer 41

Open reduction, debridement (of ruptured round ligament and fibrin in the acetabulum) and repair of the joint capsule with non-absorbable or slowly absorbable suture material.

Answer 42

after debridement of the acetabulum and reduction of the femoral head two screws & spiked washers (latter to prevent sutures slipping off) are placed in the acetabulum Sutures are then placed through a hole drilled in the greater trochanter and looped around the screws. This technique is useful for large and medium sized dogs.

Answer 43

a suitable size intramedullary pin or K wire is driven from the fovea capitis laterally through the neck to exit the lateral femoral cortex distal to the third trochanter. Following hip reduction the pin is driven through the acetabular wall and 5-6mm into the pelvic canal. The pin is then cut short but left long enough for ease of removal later. Post operative exercise reduction (or an Ehmer sling should be applied) and the pin can be removed 2-3 weeks later. This technique is no longer recommended due to pin breakage and migration.

Answer 44

after hip reduction a hole is drilled through the pelvis just cranial to the hip at the origin of the rectus femoris muscle. Another hole is drilled across the greater trochanter. Suture material (50,80 or 100lb monofilament nylon leader line) is passed through the holes and tied or secured with crimps with the hip held in a internally rotated and slightly abducted position.

Answer 45

the hip is kept reduced with a toggle pin, placed through a hole in the acetabulum to the medial aspect of the acetabulum and secured with strands of suture fed through a hole in the femural head and neck . After hip reduction the suture strands are tied around a button along the lateral femoral cortex. The hip has, postoperatively, a full range of movement, however, as the suture is placed into a very hostile abrasive environment, it will fail eventually.

Answer 46

with closed reduction the success rate is 17-75% (depending on whose paper you read! The success rate after surgery is also variable but around 85% successful. If the luxation is chronic or recurrent and there is articular cartilage damage then arthritis may develop and a permanent lameness may result. Salvage options such as FHNE or a THR may have to be considered.

Answer 47

multiple ligamentous injury can be seen after severe trauma or catching the foot in a fence. Most commonly both cruciates and one collateral ligament are ruptured. Also called stifle derangement.

Answer 48

non weight-bearing lameness after severe trauma (RTA) or catching a foot in a gate whilst jumping.

Answer 49

in acute stages the stifle joint will be swollen and painful. A thorough examination should be carried out with the animal anaesthetised.

Answer 50

examination for instability under anaesthesia – perform cranial draw, varus and valgus stress tests. Take survey radiographs and stressed radiographs to demonstrate instability. Comparison with the opposite stifle may be useful.

Answer 51

surgical repair is usually indicated. Primary repair of ruptured ligaments is often not possible so a prosthetic replacement is required using polydioxanone (PDS™) or nylon anchored through bone tunnels or around screws and washers. Wire can be used to splint the repair. The suture material will likely fail eventually but peri-articular fibrosis will hopefully be sufficient by the time this occurs.

Answer 52

With severe disruption then post-operative external coaptation should be provided with a cast, splint, or ESF for 4-6weeks.

Answer 53

Variable. At best a reduction in ROM, and some stiffness will generally result at worst the animal will be permanently lame or non-weight bearing on the limb. In working animals the prognosis is guarded for an adequate return to function.

Answer 54

Seen most commonly in greyhounds. The collateral ligaments will be damaged and these need repair using locking loop or mattress sutures of non-absorbable suture material. Small avulsion fractures can be repaired using a lag screw or wire mattress suture. Post-operative support in the form of bandaging should be applied for 2-4 weeks post operatively.

Ligaments, luxations, arthrodesis Flashcards

(79 cards)