Chapter 88 - Flexural Limb Deformities Flashcards
1
Q
Flexural Deformities plane
A
Occur in the sagittal plane
2
Q
Flexural Deformities affected primarly bones or soft tissues?
A
Affect primarily soft tissues
2
Q
Angular Limb Deformities plane
A
Occur in the frontal plane
3
Q
Angular Limb Deformities affected primarly bones or soft tissues?
A
Affect primarily osseous
structures
4
Q
Angular Limb Deformities treatment»
A
Many can initially be treated
conservatively
5
Q
Flexural Deformities require imaging?
A
Rarely require imaging/
radiography vs angular that require radiography
6
Q
Flexural Deformities treatment?
A
Most need immediate
conservative treatment
7
Q
Flexural Deformities the farrier treatment is applied where?
A
Farriery is applied to the toe
or heel
8
Q
Angular Limb Deformities the farrier treatment is applied where?
A
Farriery is applied medially
or laterally
9
Q
Describe flexural deformities in horses.
A
They are joint abnormalities where joints are held in flexed or extended positions.
10
Q
How do flexural deformities differ from angular limb deformities?
A
Flexural deformities affect the joint’s flexion, while angular deformities affect the alignment.
11
Q
Why is the term “contracted tendons” considered incorrect for persistent hyperflexion?
A
Tendons are usually functionally too short rather than actually contracted.
12
Q
Under what conditions do tendon contractions typically occur in horses?
A
After tendon injuries, often seen in adults but rarely in foals.
13
Q
How are flexural deformities typically named in veterinary practice?
A
According to the joint involved, not the tendon.
14
Q
Which limbs are more commonly affected by flexural deformities?
A
The forelimbs.
15
Q
What is the primary difference between congenital and acquired flexural deformities?
A
Congenital deformities are present at birth; acquired ones develop later.
16
Q
Which joints are most commonly affected by congenital flexural deformities?
A
The metacarpophalangeal (MCP) and carpal regions.
17
Q
In which specific cases is congenital lateral luxation of the patella relevant to flexural deformities?
A
It can cause functional flexural deformity of the stifle.
18
Q
Name two joints most frequently affected by acquired flexural deformities.
A
The distal interphalangeal (DIP) and MCP joints.
19
Q
What factors are proposed as potential causes of congenital flexural deformities?
A
Intrauterine malpositioning, diseases in pregnant mares, genetic factors.
20
Q
Explain the intrauterine malpositioning hypothesis in the context of congenital flexural deformities.
A
Crowding in the uterus, especially in large foals, can lead to deformities.
21
Q
What was the observed incidence of limb contractures in fetuses and newborn foals submitted for necropsy?
A
20% of cases.
21
Q
List any two diseases or conditions in mares that can potentially lead to flexural deformities in foals.
A
Locoweed ingestion and equine goiter.
22
Q
How are digital hyperextension deformities in newborn foals typically caused?
A
By flaccidity of the flexor muscles.
23
Describe the symptoms of mild digital hyperextension in foals.
Foals cannot maintain toes on the ground and have acutely angled MCP or MTP joints.
24
Why is it generally unnecessary to perform radiographic evaluations for digital hyperextension deformities?
No abnormalities are usually found.
25
What are the potential complications of severe digital hyperextension deformities in foal
Skin lesions due to trauma.
26
What impact can severe congenital flexural deformities have on the birthing process?
They can cause dystocia (difficult birth).
27
How can flexural deformities be managed if identified soon after birth?
With splints or casts within 30-45 minutes.
28
What action should be taken if a flexural deformity is not responsive to conservative therapy?
Use splints, medical treatment, or both.
29
Why might radiographs be necessary in cases of severe MCP/MTP flexural deformities?
To rule out abnormal bone formations that worsen prognosis.
30
Describe a mild carpal flexural deformity in foals.
The foal can stand but cannot fully straighten the carpi.
30
What is typically the prognosis for MCP/MTP flexural deformities if there are no osseous changes?
The prognosis is good for all severity levels.
31
How does the inability to manually straighten the carpus affect the prognosis for a carpal flexural deformity?
Prognosis is guarded if the carpus cannot be straightened.
32
Why are congenital PIP joint flexural deformities rarely reported?
They often involve osseous and soft tissue abnormalities.
33
What is a common cause of congenital tarsal flexural deformities?
Incomplete ossification of the tarsal bones.
34
Why is early radiography crucial for congenital tarsal flexural deformities?
To prevent irreversible bone damage.
35
Identify the anatomical area affected in foals with a ruptured common digital extensor tendon.
The dorsolateral aspect of the carpus.
36
Explain the walking posture of a foal with a ruptured common digital extensor tendon.
The foal throws forelimbs forward, extends, retracts, and may knuckle at the MCP joint.
37
Why might a ruptured common digital extensor tendon be misclassified as a flexural deformity?
It appears as a flexural deformity but lacks tendon support.
38
Describe the knuckling behavior observed in foals with a ruptured common digital extensor tendon.
They knuckle at the MCP joint when walking.
39
Why are radiographs often unnecessary for diagnosing flexural deformities?
They are generally diagnosed based on clinical signs.
40
How can incomplete ossification of certain bones complicate the prognosis for flexural deformities?
It can be associated with angular and flexural deformities.
41
What role does cross-linking of elastin and collagen play in flexural deformities?
Defects in cross-linking are associated with deformity development.
41
What treatment is recommended for foals with incomplete ossification of cuboidal bones?
Stall rest until ossification is complete.
42
What symptoms would indicate that radiographic evaluation is necessary for flexural deformities?
Severe deformity or suspected abnormal bone formation.
43
How do radiographic findings affect the management of flexural deformities?
They help identify osseous abnormalities impacting prognosis.
44
Why is excessive exercise contraindicated for foals with digital hyperextension deformities?
Fatigue may aggravate the problem.
45
What immediate action is required for severe digital hyperextension deformities?
Prompt treatment to prevent necrosis and skin excoriation.
45
What type of shoe might help foals with severe digital hyperextension?
Glue-on shoes or extensions with palmar/plantar support.
46
Why are analgesics typically unnecessary for digital hyperextension deformities?
Pain is usually minimal or absent.
47
When might toe trimming or rasping be unnecessary in treating digital hyperextension?
In mild cases where the condition self-corrects.
48
Why should adhesives be used cautiously in foals younger than 3 weeks?
To avoid heat trauma to delicate feet.
49
What risk is associated with leaving toe extensions on too long?
Constriction and deformation of the foot.
50
Why is light bandaging recommended for foals walking on the back of their pasterns?
To minimize skin trauma without fully supporting the limb.
51
What is the consequence of using splint bandages or casts on foals with digital hyperextension?
Loss of tone in flexor tendon units and risk of pressure sores.
52
Why might padding be applied over braces on the foot for digital hyperextension?
To protect the palmar/plantar region and reduce hyperextension.
53
Why is tenoplasty generally not recommended for foals with digital hyperextension?
It's not favored in small or miniature foals with the condition.
54
What initial non-surgical approach can help treat congenital flexural deformities?
Moderate exercise without overtiring.
55
How does overexertion affect foals with carpal flexural deformities?
It leads to muscular fatigue and worsens the deformity.
56
What drug is commonly used for congenital flexural deformities?
Oxytetracycline administered intravenously.
57
How quickly can deformities correct after oxytetracycline administration?
Within 24 to 48 hours in young foals.
58
What is the hypothesized mechanism of oxytetracycline in treating flexural deformities?
Inhibition of collagen gel contraction and MMP-1 reduction in myofibroblasts.
59
What serious side effect of oxytetracycline has been reported?
Acute renal failure in a foal, treated with hemodialysis.
59
Which NSAID is often prescribed for flexural deformities pain?
Phenylbutazone or flunixin meglumine.
60
What precaution should accompany NSAID use in foals?
Use of gastric protectants like omeprazole or ranitidine.
61
How do toe extensions help foals with flexural deformities?
They delay breakover and increase tensile forces in flexor tendons.
62
What might happen if toe extensions aren't braced back properly?
It could cause distraction, infection, and separation of the hoof wall.
63
Why is acrylic useful for securing toe extensions?
It interdigitates with the dorsal hoof wall, adding stability.
64
What typically occurs two weeks after applying dorsal extensions for mild DIP deformities?
The extensions are removed or detach as the deformity corrects.
65
Why are half-limb casts beneficial for DIP joint flexural deformities?
They immobilize and relax musculotendinous units.
65
What is the main limitation of splints compared to casts?
Splints may move and create pressure sores if not secured well.
66
What are some materials used to make splints?
PVC, wood, thermoplastic, fiberglass.
67
What potential complications arise with improperly applied splints?
Pressure sores or even distal limb necrosis.
68
How often should splints be reset in foals with flexural deformities?
Daily, to examine for rubbing or other complications.
69
What drug class is useful for sedation during splint application?
α2-Adrenoreceptor agonists (e.g., xylazine or detomidine).
69
What analgesic combination might be used for newborns in splinting?
Midazolam or diazepam with an opioid for pain control.
69
Why should α2 agonists be avoided in foals under 2 months?
Due to undesirable respiratory and cardiovascular effects.
70
Why might splints be preferred over casts for mild carpal flexural deformities?
hey provide adequate support without full immobilization.
71
What condition might foals with MCP/MTP joint deformities and lax tendons require?
Splinting that avoids incorporating the foot.
72
Why is padding important when applying splints?
To protect skin from excoriation and avoid rotation of the splint.
73
Why is regular padding replacement essential in splinted foals?
To reduce the risk of pressure sores.
74
What should be done if a splinted foal can't rise and nurse independently?
Assist them until they can stand unaided.
75
Why might anti-inflammatory drugs be needed in tendon stretching procedures?
To manage pain from soft tissue and joint capsule stretching.
76
Surgical treatment is most commonly carried out for________flexural deformities
Surgical treatment is most commonly carried out for carpal flexural deformities
77
What material should be used to make custom-fitted splints?
Casting materials or thermoplastic shaped to the limb’s contour.
78
Describe the surgical technique for carpal flexural deformity
GA - LR or DR (if billateral) - limb uppermost - 3- to 5-cm-long lateral skin incision is made just proximal to the accessory carpal bone. The tendons of insertion of the ulnaris lateralis and flexor carpi ulnaris are identified deep to the fascia, isolated by blunt dissection and transected approximately 2 cm proximal to the accessory carpal bone. If these tendons are the structures preventing extension of the carpus, once they have been transected surgically, the limb can be manually straightened. Routine closure of subcutis and skin is performed; a vertical incision is made over the lateral aspect of the accessory carpal bone and the tendons identified deep to the fascia. It is advisable to manipulate the limb immediately before surgery, while the foal is under anesthesia, to ascertain if these tendons tighten when forceful carpal extension is applied.
79
Lower grades with less than ___ degrees of flexion of the carpus carried the best prognosis, and the success rate in grade 3 cases fell to 57%
Lower grades with less than 40 degrees of flexion carried the best prognosis, and the success rate in grade 3 cases fell to 57%
80
What are the tendons transected in carpal deformities?
transection of the **flexor carpi ulnaris** and the **ulnaris lateralis** tendons 2 cm proximal to the accessory carpal bone can correct mild carpal deformitie
81
An extreme surgical intervention in carpal deformities is surgical of the flexor tendons and palmar capsule of the ____________ and __________ joint
surgical transection of the flexor tendons and palmar capsule of the middle carpal and antebrachiocarpal joint is required to allow the limb to be straightened, but these cases carry a worse prognosis (Figure 88-17).49 The carpal canal is opened through a medial approach; the joints are identified and subsequently opened through a horizontal incision.
82
How do you surgically correct MCP/MTP joint deformity that do not respond to treatment?
surgically by transection of the flexor tendons or suspensory ligament, but these salvage procedures are not recommended for animals intended for an athletic future.
83
Are the surgical transection of the flexor tendons or suspensory ligament in case of MCP/MTP joint deformity recommended in athletic horses?
NO, these salvage procedures are not recommended for animals intended for an athletic future
84
Severe MCP/MTP flexural deformities secondary to abnormally formed bones have been treated using .....name surgery
evere MCP/MTP flexural deformities secondary to abnormally formed bones have been treated using an arthrodesis and resulted in pasture-sound horses.
85
PIP flexural deformities result from what? are treated with which surgical tx?
PIP joint flexural deformities resulting in subluxation may be treated by means of an arthrodesis (see Chapter 82).
86
What is the recommended environment for foals with ruptured common digital extensor tendons?
A box stall.
87
How long does it typically take for a foal's locomotion to normalize with non-surgical management?
Within a few weeks.
88
What material is suggested for splinting in foals with ruptured tendons?
Thermoplastic or custom-made fiberglass splint.
88
What is the estimated duration for a thickening over the dorsal carpus to persist post-injury?
6 to 12 months.
89
What is the prognosis for cosmetic recovery in foals with conservative management?
Excellent.
90
Why is aspiration of synovial fluid discouraged in foals with ruptured tendons?
Risk of infection.
91
What is a primary risk associated with surgical management of ruptured extensor tendons?
Surgical complications.
91
What is the preferred management for ruptured common digital extensor tendons, surgical or non-surgical?
Non-surgical.
92
What is the age range most commonly associated with acquired flexural deformities in foals?
4 weeks to 4 months, and again at yearling age.
93
What ligament is commonly associated with flexural deformity due to limited passive elongation?
Accessory ligament of the deep digital flexor tendon (AL DDFT).
94
What two nutrients are closely linked to the rate of bone growth in foals?
Genetics and nutrition.
94
By what mechanism does rapid radial growth contribute to flexural deformities?
Functional shortening of the superficial flexor tendon unit.
95
What percent of horses might have the AL DDFT divided into multiple structures in the hindlimb?
About 10%.
96
What is the suggested primary cause of pain that leads to flexural deformities?
Musculotendinous contraction in response to pain.
97
Which cells in the deep digital flexor tendon are known for their contractile ability?
Myofibroblasts.
98
How quickly can flexural deformities manifest due to pain?
Within 24 to 48 hours.
99
At what angle does the dorsal hoof wall pass from stage I to stage II deformity?
90 degrees.
99
What percentage of longitudinal bone growth is insufficient at any age to cause flexor tendon shortening?
Sufficient percentages are undetermined; muscle tension may cause deformity more than bone growth.
99
Which structure is often released first in surgery for MCP deformities due to flexural deformity?
The structure with the most tension (deep or superficial digital flexor tendon or suspensory ligament).
100
What consequence is associated with untreated stage II DIP deformity?
Worsened prognosis and permanent changes.
101
What is the main reason that DIP deformities often affect forelimbs rather than hindlimbs?
Distribution of weight and conformation.
101
What percent of stage II deformities are likely to have poorer outcomes compared to stage I?
Percentage not given but generally worse prognosis.
102
What is the primary difference between mild, moderate, and severe MCP/MTP deformities?
Degrees of flexion, with severe cases over 180 degrees of flexion at all times.
102
What is the main inciting factor for pain-related acquired flexural deformities?
Contraction of the musculotendinous unit.
102
What hoof condition is common due to uneven ground contact in DIP deformities?
Boxy or clubbed hoof shape.
103
At what degree does a severe MCP/MTP flexural deformity hold during rest?
Over 180 degrees.
104
Which joint is most commonly affected in acquired flexural deformities?
MCP joint
105
What percentage of hindlimbs lack the AL DDFT altogether in horses?
Approximately 6%.
106
Which breed has a higher risk of hindlimb AL DDFT desmopathy?
Cobs.
107
What diagnostic tool is essential for hindlimb AL DDFT assessment in flexural deformities?
Ultrasonography.
108
What percent of deformities become fixed despite healing the original injury?
Percentage not specified; generally depends on management.
109
What joint change can worsen due to prolonged weight-bearing limitations?
Permanent flexural deformity.
110
In what cases are ultrasonographic evaluations highly recommended?
In cases of hindlimb MTP deformities and AL DDFT injuries.
111
Which tendon is commonly palpated to determine if it’s affected in MCP/MTP deformities?
Superficial or deep digital flexor tendons.
112
What percent of flexural deformities are treated successfully with early conservative management?
Generally high success rate with early treatment, but specific percentage varies.
113
What is the primary goal of surgery for severe MCP/MTP deformities?
Release the primary tendon under tension.
114
What condition often necessitates surgery in acquired MTP deformities in adults?
AL DDFT desmopathy or chronic flexural deformity.
115
What is one surgical complication associated with improper flexor tendon handling?
Tendon adhesions.
116
What percentage of adult horses recover from MCP/MTP deformity post-surgery?
Recovery rates vary but can be good if treated promptly.
117
Why is early diagnosis crucial for acquired flexural deformities?
Prevents progression and worsened prognosis.
118
Acquired flexural deformities of the MCP joint have also been reported in mature horses secondary to
to desmitis of the accessory ligament of the deep digital flexor tendon,64 and in a case of nonresponsive digital sheath sepsis, which led to rupture of the flexor tendons within the sheath
119
What diagnostic imaging is recommended for assessing acquired flexural deformities of the metatarsophalangeal (MTP) joint in adult horses?
ltrasonography of the accessory ligament of the deep digital flexor tendon (AL DDFT).
120
In the hindlimb, acquired flexural deformity of the MTP joint is an infrequent or frequent condition of adult horses ?
infrequent to have deformity of MTP
120
In what percentage of horses is the accessory ligament of the deep digital flexor tendon (AL DDFT) of the hindlimb absent?
In only 6% of horses.
121
What prognosis is generally expected for mild flexural deformity cases that require only corrective shoeing?
A good prognosis for resolution.
121
At what age are flexural deformities of the proximal interphalangeal (PIP) joint primarily diagnosed in foals?
In rapidly growing weanlings.
122
What is one of the main factors influencing the development of acquired flexural deformities in foals, according to the text?
Contraction of the musculotendinous unit in response to pain.
123
Which radiographic changes are associated with chronic flexural deformities of the distal interphalangeal (DIP) joint?
Osteoarthritis, modeling of the dorsodistal aspect of the distal phalanx, and rotation of the distal phalanx in the hoof capsule.
124
Why is it important to monitor the mineral composition of soil and drinking water in the treatment of flexural deformities?
To adjust mineral and trace mineral intake for foals, which may affect growth and contribute to deformities.
125
What is a possible negative effect of exercise on foals with secondary painful flexural deformities?
Uncontrolled exercise can worsen the painful stimuli and increase stress on the contralateral limb.
125
Why might NSAIDs be given to foals with acquired flexural deformities?
To reduce pain, helping the foal stand and ambulate without exacerbating the deformity.
126
What role does corrective shoeing play in the management of DIP joint flexural deformities?
it helps stretch the deep digital flexor musculotendinous unit while protecting the toe from excessive wear.
126
What outcome can result from over-trimming the heel in DIP joint flexural deformities?
Increased strain on the dorsal toe, leading to greater leverage on the dorsal laminae.
127
Figure 88-9. The same foal as in Figure 88-8. Because of a lack of extensor support, the foal was unable to walk without stumbling. Application of a distal limb splint improved the foal’s ability to walk and support weight on the limb.
128
Figure 88-10. (A) A newborn foal with marked digital hyperextension in the hindlimbs. (B) The same foal immediately after application of a pair of Dallmer glue-on shoes. A clear plastic wrap (not shown) is used to ensure good contact between shoe and hoof during the hardening process of the polymethyl methacrylate (PMMA). Note the ability of the foal to bear weight on the soles after shoe application.
129
Figure 88-13. A foal with flexural deformities of both carpi, which were treated with application of splints, oxytetracycline, and analgesics. Because both forelimbs were splinted, the foal required assistance to stand but could walk in the splints unaided once it was upright.
129
Figure 88-11. Application of metal plantar extensions in a standing sedated foal with a severe digital hyperextension in the hind feet. The metal strips are curved over the toe and secured to the foot with acrylic.
130
Figure 88-12. A foal with marked digital hyperextension shod with metal palmar extensions, which have been covered with padding and elastic bandage to provide additional protection to the palmar pasterns and to prevent injury to the mare and foal from the metal extensions
131
Figure 88-14. A PMMA toe extension applied to a foal following a desmotomy of the accessory ligament of the deep digital flexor tendon for treatment of a flexural deformity of the distal interphalangeal joint. The toe extension stretched the deep digital flexor musculotendinous unit, and by filling the gap between the toe extension and the dorsal hoof wall with acrylic, the distraction forces between the hoof wall and the underlying laminae are neutralized.
132
Figure 88-16. A custom-made splint for a foal with a flexural deformity of the MCP region. The splint has been made using the normal MCP region as a template and is now ready to be placed on the limb with a flexural deformity. The extent of the deformity can be seen as the disparity between the splint and the affected limb.
133
Figure 88-17. A foal with a severe flexural deformity in the carpal region, which was unresponsive to treatment.
134
Figure 88-18. A stage I flexural deformity of the DIP joint. Note that the dorsal hoof wall has not passed the vertical and that the distodorsal tip of the hoof wall has flared from the forces caused by the abnormal foot position.
135
136
Figure 88-3. A newborn foal with mild digital hyperextension. Note the skin over the heel bulbs is in contact with the ground; the skin must be protected from excoriation.
136
Figure 88-1. A congenital flexural deformity of the stifle caused by lateral luxation of the patella secondary to hypoplasia of the trochlear groove.
137
Figure 88-4. A premature foal showing severe digital hyperextension. The foal responded quickly to restricted exercise.
138
Figure 88-5. A congenital flexural deformity of the MTP joint. The foal responded to splinting, oxytetracycline administration, and analgesics
139
Figure 88-6. (A) A marked bilateral flexural deformity of the carpi. The foal is unable to completely straighten the limbs. (B) The foal 8 weeks after treatment with tube casts for 4 days.
VetBooks
140
Figure 88-7. (A) Lateromedial (LM) radiographic view of a newborn foal with an anomaly of the proximal MTIII. The small tarsal bones have not been irretrievable damaged. The foal was treated with exercise restriction. (B) The same foal as a yearling with acceptably normal radiographs.
141
Figure 88-8. Rupture of the common digital extensor tendon in the right forelimb of a young foal, which can create the appearance of a flexural deformity. Note the characteristic bulge over the dorsolateral aspect of the carpus. The foal also has a moderate carpal valgus deformity in the left forelimb.
141
Figure 88-7. (A) Lateromedial (LM) radiographic view of a newborn foal with an anomaly of the proximal MTIII. The small tarsal bones have not been irretrievable damaged. The foal was treated with exercise restriction. (B) The same foal as a yearling with acceptably normal radiographs.
142
Figure 88-6. (A) A marked bilateral flexural deformity of the carpi. The foal is unable to completely straighten the limbs. (B) The foal 8 weeks after treatment with tube casts for 4 days.
VetBooks
143
Figure 88-4. A premature foal showing severe digital hyperextension. The foal responded quickly to restricted exercise.
144
Figure 88-3. A newborn foal with mild digital hyperextension. Note the skin over the heel bulbs is in contact with the ground; the skin must be protected from excoriation.
145
Figure 88-15. (A) A 4-month-old foal with a stage I flexural deformity in the DIP joint. The hoof wall is flared and cracked and bruising of the wall is evident; (B) The same foal after trimming of the foot with removal of excess heel and removal of the broken hoof at the toe. Note the foal cannot place the heel to the ground; (C) The foal after application of an acrylic toe extension; the foal can now place the heel to the ground. (
146
The deformities of DIP are divided and how many stages?
stage I and stage II
stage II worse prognosis
147
describe stage 1 and stage 2 in the DIP joint
Stage I deformities (Figure 88-18) have a more upright dorsal hoof wall where the angle described by the dorsal hoof wall and sole is greater than 60 degrees but less than 90 degrees
In stage II deformities (Figure 88-19), the dorsal hoof wall has passed 90 degrees and is beyond the vertical plane.
148
how many degrees of MCP/MTP flexural deformities have been describe?
3 degress:
**1) mild** (rarely flex greater 180 degrees)
**2) moderate deformities** (have greater 180 degrees flexion
**3) severe deformities** have greater than 180 degrees flexion all times
149
What potential complication can arise with the use of toe extensions for DIP joint flexural deformities?
It may lead to stumbling and abnormal flaring of the dorsal hoof wall.
150
What is the purpose of applying a toe extension or glue-on rubber shoe in DIP joint flexural deformities?
To increase tension in the deep digital flexor tendon and prevent excessive toe wear.
151
What is the main reason for casting the distal limbs of foals with flexural deformities?
To temporarily weaken tendons, allowing correction of the deformity.
152
Why is surgery indicated for stage I flexural deformities of the DIP joint?
Desmotomy of the AL DDFT is performed when conservative treatment is insufficient.
153
What is a preferred surgical approach for the desmotomy of the accessory ligament, and why?
The lateral approach, as it avoids the major neurovascular bundle located medially.
154
Why might conservative postoperative management be preferred over free pasture exercise in older foals following surgery?
To avoid excessive fibroplasia and scarring at the surgical site.
155
What is a key advantage of the ultrasound-guided desmotomy technique in standing horses?
It provides greater success in restoring normal hoof conformation in younger horses.
156
Why might horses treated surgically for DIP flexural deformities at a younger age have better prognoses?
Younger horses respond better to desmotomy, and fewer contractures have developed.
157
What deformity is associated with an angle greater than 115 degrees in DIP flexural deformities, and what surgical procedure might be required?
Stage II deformity requiring deep digital flexor tenotomy.
158
What two sites are commonly used for tenotomy in the management of DIP flexural deformities?
The midmetacarpus and midpastern regions.
159
How does proper corrective shoeing alleviate MCP joint flexural deformities?
By raising the heel with wedge pads, which reduces strain on the deep digital flexor tendon.
160
How do toe extensions help in MCP joint flexural deformities?
They create tensile stress on the flexor tendons, promoting lengthening of the musculotendinous unit.
161
Desmotomy of the acessory (check) ligament of the DDFT is the treatment of choice of what type of flexural deformity?
The treatment of choice for stage I flexural deformities is desmotomy of the AL DDFT (Figure 88-21)
162
The desmotomy of the acessory ligament of the DDFT is accessed by LR or DR?
LR and you can access one leg from medial and uppermost limb from lateral access
163
what are the advantages of lateral and medial approach in the desmotomy of the ALDDFT
advantages of a lateral approach are that the major neurovascular bundle, located medially at this level, can be avoided, and the ligament is in a more lateral position. The major advantage to the medial approach is cosmetic, although the procedure is more difficult
164
describe the surgical tx of ALDDFT
5-cm skin incision, centered at the junction between the proximal and middle third of the MCIII, is made over the deep digital flexor tendon. The subcutaneous tissues and fascia are bluntly separated and the tendinous structures are identified.
If medial approach deflect neurovascular bundle
curved hemostatic forceps is introduced and advanced following the slightly curved surface of the tendon to the opposite side, where the forceps is spread and turned. The AL DDFT lying dorsal to the tendon is elevated to the level of the skin incision. Manipulation of the foot in a dorsal direction tightens the ligament and ensures the isolation of the correct structure it is sharply transected with a scalpel blade. Dorsal rotation of the DIP joint produces at least a 1-cm gap between the transected ends of the ligament.
Paratendon, subcut skin absorb 2-0 sutures continuous pattern
164
what is the postoperative advice after desmotomy of ALDDFT?
- might need application of a toe protection or extension
- Repeated hoof trimming using rasping to lower the heels i
- Young foals and those without long-standing contracture are allowed controlled exercise within 3 to 6 days after the surgery
- Free pasture exercise is encouraged after 2 weeks
- In older foals and those with chronic or severe contracture, limiting exercise for a period of months might prevent excessive fibroplasia at the surgery site.
- NSAID for relieve of pain
165
prognosis of the desmotomy of the acessory ligament of DDFT
prognosis for athletic function is good; in one study 86% of horses treated before 1 year of age were subsequently used for their intended purpose.71 Horses treated after 1 year of age had a lower success rate of 78%.
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In which cases do you perform tenotomy of the DDFT?
Stage II flexural deformities might not correct after desmotomy of the AL DDFT or where the degree is >115º
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prognosis for tenotomy of DDFT in stage II DIP joint flexure?
prognosis for return to function is usually guarded
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where are the 2 mains surgical zones for DDF tenotomy
midpastern
midmetacarpus
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what is the surgical approach for tenotomy of DDFT in the pastern area?
The distal approach centers at the palmar and median aspect of the pastern region and enters through the digital flexor tendon sheath just distal to the bifurcation of the superficial digital flexor tendon.
The deep digital flexor tendon is identified, exteriorized, and transected with a scalpel blade. Immediate retraction of the proximal stump into the tendon sheath is noted. The tendon sheath may or may not be sutured using routine technique in addition to the subcutaneous tissue and the skin.
application of a shoe with a heel extension is necessary
NSAIDs
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describe surgical approach for tenotomy of DDFT in the midmetacarpus area
GA - LR
Medial or lateral approach. The advantage of this approach is the greater distance from the feet and the fact that a tendon sheath is not invaded. Additionally, the procedure is easier to perform at the midmetacarpal level and can be performed as a standing procedure. However, scarring associated with marked disfigurement of the tenotomy site can be an undesirable sequela.
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what are the 2 surgical approach of DIP deformties?
desmotomy of ALDDFT
tenotomy of DDFT
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What are the medical approach to MCP/MTP deformities?
proper nutrition,
physiotherapy - hopping animal to strecht soft tissues
analgesics - for pain management
corrective shoeing - elevate heels with wedge
application of splints - place fetlock palmar to foot
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which MCP/MTP deformity is immediate candidate to surgical intervention?
horse with an MCP angle of greater than 180 degrees (forward of the hoof) are immediate surgical candidates
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a horse with MCP angle greater than 180 what is the surgical plan?
Severe cases with an MCP angle of greater than 180 degrees benefit from both desmotomies DDFT or ALS DFT plus a tenotomy of the superficial digital flexor tendon
175
Transection of the ALSDFT should be done when you palpate what?
tension in the superficial digital flexor tendon during manipulation
176
describe the surgical approach of ALSDFT - mention the site of incision
2 surgical approach:
both consist of the **medial distal physis** of the **radius, the chestnut**, and the **cephalic vei**n. An approximately **10-cm skin incisio**n is centered along the chestnut and made craniad to the cephalic vein. The **subcutaneous tissu**e is bluntly separated, and communicating branches to the **cephalic vein** are isolated, double ligated, and transected between ligatures
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for desmotomy of ALSDFT describe one surgical tx
Approach the accessory ligament craniad to the** flexor carpi radialis muscle**.
The **oval foramen** in the **carpal fascia** can serve as the distal border of the desmotomy incision.
The **carpal fascia is transected **carefully, and the ensheathed flexor carpi radialis muscle is identified. Both the cephalic vein and the flexor carpi radialis muscle are displaced using a self-retaining retractor. The desmotomy of the fan-shaped accessory ligament is performed, taking care to avoid inadvertent injury to the **palmar carpal rete.** After transection of the ligament, the radial head of the deep digital flexor muscle appears and the **carpal sheath becomes visible**. Hemostasis is established, and the carpal fascia, subcutaneous tissues, and skin are closed routinely
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what is the second surgical tx of ALSDFT approach?
invasion of the **sheath of the flexor carpi radialis tendon **(Figure 88-23).
After reflecting the **flexor carpi radialis **tendon in the sheath with a self-retaining retractor, the **craniolateral wall and accessory ligament** are identified. A curved **Kelly forceps **is placed u**nder the distal border** and spread. The **ligament is then transected in a distal to proximal direction**. Care is taken to **avoid injury to the nutrient artery of the superficial flexor tendon**, which enters along the proximal border of the accessory ligament.
Inadvertent incision of the carpal sheath is of no consequence. The tendon sheath is closed using a continuous suture pattern with 2-0 or 3-0 synthetic absorbable material. The rest of the closure is routine.
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what are the 3 surgical approach to acessory ligament of the superficial digital flexor tendon
desmotomy of ALSDF craniad to flexor carpi radialis
desmotomy of ALSDF through flexor carpi radialis sheath
tenosocpy (chapter 84)
180
what is the salvage procedure in case o MCP refractory to the desmotomy of ALSDF?
desmotomy of the medial and lateral branch of the suspensory ligament may be performed for salvage purposes in persistent cases
181
what is the consequence of desmotomy of the medial and lateral branch of the suspensory ligament ?
luxation of PIP joint
182
describe the surgical approach desmotomy of medial and lateral branch of suspensory ligament
Stab incision is made directly over the suspensory branch, the subcut tissues are separated with a Kelly forceps, and a curved tenotome is introduced. By applying pressure with a sawing motion, the previously undermined suspensory branch is transected. Care should be taken to prevent inadvertent injury to the palmar artery and vein and the MCP joint capsule. The skin is closed using a few simple interrupted sutures. The same procedure is performed on the other side of the limb.
183
Horses with severe contractural deformities respond well to medical and surgical tx?
Horses with chronic or severe flexural deformities respond poorly to any treatment, including surgery
184
the prognosis is the same for superior check ligament desmotomies and inferior check ligament?
No, superior check ligament desmotomies do not carry as good a prognosis as inferior check ligament desmotomies.
185
MTP joint secondary to desmopathy of the AL DDFT is associated with a ___________prognosis with 90% remaining lame and only a minority regaining a normal posture.
MTP joint secondary to desmopathy of the AL DDFT is associated with a guarded prognosis with 90% remaining lame and only a minority regaining a normal posture.
186
In the carpal region what are the two treatment options»?
medical management - Passive stretching exercises are indicated.
surgical - **tenotomy of the ulnaris lateralis** and **flexor carpi ulnaris** tendons can be performed with good result
187
what are the reasons for carpal deformities?
long-term debilitating injuries that prevent weight bearing on the limb should be treated with splints early in convalescence to prevent development of a flexural deformity
188
The clicking sound is typical in one type of flexural deformity, which one?
The clicking sound associated with dorsal snapping of the PIP and MCP area could also be observed in foals with persistent foal hoof at the tip of the hooves
189
Carpal flexural deformity may respond to medical tx, what is the medical tx?
Affected horses may respond to exercise restriction and analgesics,
190
what is the surgical approach for carpal flexural deformity?
surgical transection of the accessory ligament of the deep digital flexor tendon and the tendon of the medial head of the deep digital flexor tendon at the level of the chestnut has beendescribed
191
common complications of the treatment of flexural deformities
Splint-associated pressure sores are the most often encountered complication
Persistent hematoma formation, especially at the site of transection of the ALS DFT, wound dehiscence, and infections are the most common complications encountered after surgical treatment. Whenever fever, leukocytosis, warmth at the surgery site, or increased pain further investigation needed
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Figure 88-21. Surgical technique of desmotomy of the ALDDFT (inferior check ligament desmotomy). (A) Location of the surgical site on the medial, or in most cases the lateral, side of the limb (dotted line). (B) The paratenon enclosing the deep flexor tendon and the accessory ligament is incised. (C) The accessory ligament is isolated along its division plane with the deep digital flexor tendon. a, Musculus interosseus (suspensory ligament); b, accessory ligament of the deep digital flexor tendon; c, deep digital flexor tendon; d, superficial digital flexor tendon. (D) The isolated and elevated accessory ligament is transected along the dotted line.
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Figure 88-22. A toe extension incorporated into a shoe for treatment of an acquired flexural deformity of the MCP joint.
194
Figure 88-23. Surgical technique of ALSDFT (superior check ligament desmotomy). (A) Location of the surgical site relative to the anatomic landmarks: cephalic vein, distal radial physis, and chestnut. (B) The tendon sheath of the flexor carpi radialis muscle is incised. (C) The flexor carpi radialis tendon is retracted, allowing visualization of the craniolateral tendon sheath wall. The site of the desmotomy incision is marked with a dotted line over the accessory ligament, which is at this location part of the craniolateral tendon sheath wall. (D) The accessory ligament desmotomy is completed, allowing digital access to the radial head of the deep digital flexor muscle. (
