Joint Luxations Flashcards
1
Q
What is the most common direction for a coxofemoral luxation?
A
- Craniodorsal (70%)
2
Q
What is the second most likely direction for a coxofemoral luxation?
A
- Caudoventral
3
Q
What are most common causes of coxofemoral luxation?
A
- Trauma (motor vehicle accident, jumped/dropped)
- Unknown
- Non-weight bearing lame
4
Q
Physical exam findings of coxofemoral luxation (craniodorsal luxation)?
A
- Craniodorsal luxation: Stifle externally rotated and limb adducted
- Pain/discomfort at the hip
- Non-weight bearing
- Loss of the “hip triangle” (craniodorsal luxation)
- Short limb
5
Q
Physical examination findings for caudoventral luxation?
A
- Stifle internally rotated and hip abducted
- Pain/discomfort at hip
- Non-weight bearing
- Decreased greater trochanter
- Longer limb
6
Q
Diagnosis of hip luxation?
A
- Orthogonal view radiographs
7
Q
What can you see on radiographs with a hip luxation?
A
- Looking for any fragments from an avulsion fracture of the round ligament
- Also confirming the direction of displacement
8
Q
When to do closed vs open hip reduction?
A
- Closed reduction is best done within 5-7 days (50%) success
- Open reduction is best performed if femoral head does not stay reduced, or if you are >7 days post trauma, or if there are avulsion fractures (85-90% success)
9
Q
What is “post-reduction” treatment for a closed reduction?
A
- Ehmer sling for 10-14 days
- Restrict activity for 4-6 weeks
- keeping the limb abducted and internally rotated
10
Q
What treatment do you use for caudoventral hip luxation (we didn’t talk about in class)?
A
- Hobbles
11
Q
What is post-op care for an closed reduction?
A
- +/- Ehmer Sling bandage for 7-10 days post-op
- Restrict activity for 4-6 weeks
12
Q
If the hip will not stay reduced with a closed reduction, what are surgical options to consider?
A
- Femoral head and neck ostectomy
- Total hip replacement
13
Q
Techniques of open reduction
A
- Capsulorraphy (suture capsule back together)
- Toggle pin (new prosthetic ligament of teres by tunneling between subtrochanteric fossa out of the femoral neck and fovea)
- Transarticular pinning
- Prosthetic capsule
- DeVita Pinning (sciatic nerve)
- Transposition of greater trochanter
- Must completely debride the coxofemoral joint
14
Q
Complications of traumatic coxofemoral joint luxation?
A
- Reluxation (can happen with open or closed); often indicates underlying canine hip dysplasia
- 2° osteoarthritis
- Infection (open)
- Revision surgery: FHNO, THRA
15
Q
Prognosis for lame free function for a craniodorsal coxofemoral joint luxation
A
- Good to very good
16
Q
What is the direction for most traumatic shoulder luxations, and who gets traumatic medial shoulder luxations?
A
- 75% medial (small breeds)
- large breeds get lateral
17
Q
How common are cranial or caudal shoulder luxations?
A
- Generalized instability
18
Q
What direction are most congenital shoulder luxations, and who gets them?
A
- medial
- Spontaneous in toy breeds (medial patella luxation)
19
Q
History of shoulder luxations
A
- Variable; +/- trauma or spontaneous
20
Q
Physical examination of shoulder luxations
A
- Toe touching or non-weight bearing (traumatic)
- Weight-bearing +/- lameness (congenital or “chronic” traumatic)
- Abducted and externally rotated
- Shoulder joint swelling
- Altered anatomy between the acromion of the scapular and greater tubercle of the humerus (for medial luxation; acromion may be pretty prominent)
- Pain on palpation/manipulation of the shoulder joint
- Joint instability on palpation
21
Q
What direction is the shoulder rotated with a medial shoulder luxation?
A
- Abducted and externally rotated
22
Q
Diagnostics for shoulder luxations
A
- Radiographs (orthogonal views)
23
Q
Diagnostics for congenital luxations
A
- Malformation of the glenoid and humeral head
- Radiographs (orthogonal views)
24
Q
When to use closed reduction for shoulder luxation (and what would you use for a medial vs lateral luxation)?
A
- Recent traumatic luxations
- Velpeau sling for medial luxation (2 weeks)
- Spica splint for lateral luxation (2 weeks)
25
When to use open reduction for a shoulder luxation (and what treatments would you use)?
- If unstable, can't reduce, concurrent fractures, or recurrence
- Capsulorrhaphy, imbrication of surrounding tissues +/- biceps brachii tendon transposition excisional arthroplasty of the humeral head
26
Treatment for congenital luxations
- Excisional arthroplasty of the humeral head
- Arthrodesis
- Biceps brachii tendon transposition not rewarding
- Hard to do
27
What is the anatomy for medial shoulder instability?
- Medial glenohumeral ligament, which provides passive stabilizers
- Subscapularis tendon on the medial side
28
Who gets medial shoulder instability?
- Repetitive motion injury in sporting and agility dogs
29
What happens with medial shoulder instabilities?
- Partial or complete disruption of the ligament and/or tendon
- 80% of shoulder-based instabilities
30
History of medial shoulder instability
- Chronic or persistent weight-bearing lameness
- variable response to NSAIDs and rest
- Gets worse with exercise
31
Physical examination findings for medial shoulder instability
- Pain on flexion or extension; marked with abduction
- Lateral drawer sign (humerus held neutral to glenoid and laterally lifted, which will be more pronounced with medial disruption of the joint capsule)
32
Diagnostics for medial shoulder instability
- Radiographs: Often have developed osteoarthritis in 50% of cases
- Arthroscopy must be done
33
Therapy for medial shoulder instability
- Radiofrequency based capsular shrinkage, which has mixed results
- Restrict for 4-6 weeks wit Hobbles
34
Prognosis for medial shoulder instability
- Guarded to good
35
What direction are most traumatic elbow luxations?
- Lateral luxations
| - Medial side of the humeral condyle is longer and more resistant to popping out
36
History of traumatic elbow luxations
- Often trauma is unknown
37
Physical examination for elbow luxations
- Toe touching lameness or non-weight bearing
- Foot does not touch the ground when standing or sitting )similar to fibrotic contracture of the infraspinatus tendon)
- Antebrachium and foot are abducted
- Elbow flexed
- Pain and increased elbow width
- Resistance to flexion
38
Diagnostics for elbow luxations
- Radiographs (2 view)
39
When to do closed reduction for elbow luxation?
- If recent injury
40
How to stabilize a luxated elbow post reduction?
- Modified Robert Jones (reinforced), 5-7 days
| - Restricted leash activity for 2+ weeks
41
When to do an open reduction for an elbow luxation?
- If not stable post closed reduction (especially with collateral ligament constraint loss)
- Cannot reduce
- Associated fractures
42
Prognosis for lame free function for elbow luxations
- Very good to excellent
43
What determines prognosis for lame free function for elbow luxations?
- Based on resulting articular trauma and use of physical therapy
44
How common is traumatic luxation of the stifle?
- Uncommon traumatic injury in dogs and cats
45
What occurs as a side effect of traumatic luxation of the stifle?
- Derangement of passive stifle joint stabilizers
- Collateral ligaments
- Cruciate ligaments
- +/- menisci
- Usually joint capsule intact
46
History for traumatic luxation of the stifle
- +/- trauma known
| - Acute onset of non-weight bearing lameness
47
Physical examination for traumatic luxation of the stifle
- Weight-bearing to non-weight-bearing lame
- Cranial and caudal drawer, genu valgus and/or varus
- +/- crepitus
- Marked swelling of stifle joint
- Pain on palpation
48
Diagnostics for traumatic luxation of the stifle
- Radiographs (orthogonal)
49
Treatment overview for traumatic luxation of the stifle
- Temporary trans-articular pinning
| - Reconstruction of ligamentous constrains and trans-articular external skeletal fixator
50
Temporary trans-articular pinning procedure
- 5-7 weeks
- Reinforced bandage/splint for duration of pinning
- Stifle held at 30-40 degrees
- Expect reduction of 30-40 degrees of range of motion
51
What is recommended if there is poor function following trans-articular pinning surgery?
- Arthrodesis, total knee replacement
52
Reconstruction of ligamentous constraints and trans-articular external skeletal fixator how long and prognosis?
- 6 weeks
| - Lame-free function can be good (rehab required)
53
Which joints can be affected in carpal sprains and luxations?
- Antebrachiocarpal joint
- Middle carpal joint
- Carpometacarpal joint
54
What can be a common comorbidity with carpal sprains and luxations?
- Avulsion fractures of carpal bones
55
History for carpal sprains and luxations?
- Maybe known trauma
56
Physical examination for carpal sprains and luxations
- Weight-bearing to non-weight bearing lameness
- May be palmigrade during gait and standing
- Swelling over carpus
- Pain on extension of carpus +/- crepitus
- Hyperextendable carpus
- Producible carpal valgus and/or varus
57
Diagnostics for carpal sprains and luxations?
- radiographs +/- stressed views
58
Treatment for 1° or 2° carpal sprains with no instability
- Splinting for 3-4 weeks
- leash restraint for 6 weeks
- If palmigrade or remains lame, consider arthrodesis
59
Treatment for instability or carpal fractures (expected with 3° sprains)
- Pancarpal arthrodesis
| - Coaptation (bivalve cast) for 6-10 weeks
60
What can cause tarsal sprain or luxation?
- Trauma can cause both hyperextension and shearing injuries to the tarsus
61
Which tarsal joints are at greatest risk of sprain or luxation?
- Tarsocrural
- Proximal intertarsal
- DIstal intertarsal
- Tarsometatarsal joints at risk
62
Possible comorbidities with tarsal sprain or luxation
- Avulsion and direct fractures of the tarsal bones are possible
- Sprains, subluxations, and luxations can also involve both plantar and dorsal ligamentous support
- Short and long sections of the collateral ligaments
63
History for tarsal sprain/luxation?
- +/- known trauma
| - Acute lameness
64
Physical examination for tarsal sprain/luxation?
- Swelling of the tarsus
- Malalignment of tarsocrural joint or other areas of tarsus
- If shearing injury, exposure of tarsal bones
- Instability and pain on palpation
- May ambulate and stand with plantigrade position
65
Diagnostics for tarsal sprain/luxation
- Radiograph
| - +/- stress views
66
Treatment for 1° or 2° sprains with no gross instability for a tarsal sprain or luxation
- Coaptation for 3-4 weeks
| - If unstable after treatment, surgery
67
Treatment for 3° sprains with/without shearing injuries with gross instability
- Open wound management (shearing injuries) FIRST
- Temporary transarticular external fixator can be helpful
- Arthrodesis later if necessary
68
Closed management for 3° sprains
- Pantarsal arthrodesis (tarsocrural joint)
- Partial arthrodesis (proximal, distal intertarsal joint, tarsometatarsal joint)
- Coaptation (bivalve cast) 8-12 weeks
69
What can be sequela for joint luxations?
- Osteoarthritis
70
Collateral ligament injuries are also known as what?
- Extra-articular sprains
71
Comorbidities with collateral ligament injury
- Rarely involved as a single injury
| - Not uncommon to have concurrent degloving and shearing injuries with carpal and tarsal injuries
72
Injury classification for collateral ligament injury
- 1° sprain
- 2° sprain
- 3° sprain
73
1° sprain definition (collateral ligament sprain)
Minor stretch or tear
74
2° sprain definition (collateral ligament sprain)
Moderate stretch or tear
75
3° sprain definition (collateral ligament sprain)
- Tearing/rupture, avulsion
76
When is surgery indicated for collateral ligament sprains?
- 3° and some 2° sprains
77
WHere are collateral ligaments most common?
- Distal joints (carpus and tarsus)
78
Clinical signs for collateral ligament injury?
- Joint effusion
- Discomfort over affected area of joint capsule
- Non-weight bearing
- Varus (LCL) or valgus (MCL) instability
79
Diagnostics for collateral ligament injury
- Radiographs with stress views
| - May see an avulsion component
80
Treatment for a 1° or 2° collateral ligament sprain
- Ice (24-72 hours post injury)
- Heat (after 72 hours)
- NSAIDs for 5-7 days
- Splint or bivalve cast for 4-6 weeks
- Restrict activity for 6-8 weeks
81
Treatment for 3° or some 2° collateral ligament sprain
- Primary repair (going in and suturing together ligaments)
| - Secondary repair (prosthetic suture ) - splint/coapt for 4-6 weeks and restrict activity for 6-8 weeks
82
What treatment for severe disruption of collaterals or other supporting ligamentous structures for collateral ligament injury?
- Arthrodesis
83
If there is a concurrent degloving or shearing injury, do you treat the wound before or after treating the collateral ligament injury definitively?
- Wait until after wound is healed
84
Prognosis for 1° or 2° sprain
- Very good to excellent if stable following treatment
85
Prognosis for 3° or some 2° sprain
- Primary repair or secondary repair
- Very good to excellent if stable following treatment
- If degloving or shearing injury is not addressed first, then higher probability of infection (septic arthritis and/or osteomyelitis)
- If instability is not completely addressed, then osteoarthritis may manifest itself clinically
86
Which joint luxations should have closed reductions attempted first?
- Hip, shoulder, elbow
87
When should attempts at closed reductions not be attempted first?
- Stifle, carpus, tarsus
