Chapter 91 - Foot part III articular surgery Flashcards
1
Q
What is the preparation mandatory previous to hoof surgery?
A
The hoof should be thoroughly cleaned the day before surgery, and the coronary band and the phalangeal region should be clipped.
The entire area is scrubbed, and an antiseptic bandage is applied overnight.
The shoe may be left in place.
2
Q
For atrhoscopic interventions in the forelimb the horse is positioned in ___________________ recumbency and hindlimb is positioned in _________________________
A
dorsal dor FL
lateral for HL easier manipulation to the reciprocal apparatus
3
Q
Describe the joint position for arthrosocoy of the DIP joint
A
With the DIP joint in an extended position
4
Q
With how much do you distend the DIP joint?
A
20 mL of Ringer Lactate
5
Q
what is the needle position for DIP joint distension?
A
dorsolateral-to-distomedial direction from 2 cm proximal to the coronary band and 1.5 cm abaxially.
6
Q
What is the portal used for dorsal arthro approach of DIP joint?
A
2 cm proximal to the coronnary band and 1.5 cm abaxially using No 11 scalpel blade alond the needle
Sleeve and blunt obturator are advanced togehet into the joint with a rotating movement
Obturator is replaced by arthroscope
7
Q
Working with a dorsolateral arthroscope portal allows inspection of a _________ (medial or lateral) fragment
A
medial fragment
8
Q
removal through an instrument portal positioned directly over the ___(1w)
A
fragment
9
Q
what are the anatomic landmarks once you are inside the DIP joint?
A
The dorsal joint pouch is very small, providing little room for recognition of the anatomic landmarks.
The middle phalanx is recognized by its articular cartilage surface and the proximal prominent ridge, which provides access to the dorsal outpouching of the joint.
The synovial membrane, located at the dorsal aspect of the joint cavity, is covered with synovial villi, which partially obstruct the view.
Often the osteochondral fragment of the extensor process is hidden behind the villi.
10
Q
what instrument do you use to remove a fragment that usually are well attached to the soft tissues?
A
elevator
11
Q
in the end of removal of the fragment what do you do in the joint?
A
fracture bed is inspected and curetted
Flush joints
Portals closed with 2 simple interrupted sutures of an absorbable monofilament material
11
Q
Posoperative bandage of arthroscopy of DIP is mainted for how long?
A
2 weeks
4 weeks of stall rest with slowly return to work after
12
Q
What is the prognosis of the horses with fragments in the DIP?
A
The prognosis depends on the nature
Young horses good prongosis
Older horses with concomitant OA decreases
13
Q
What is the position of the horse for the palmar DIP joint approach?
A
lateral recumbency and joint disteded througha dorsally placed needle - distension allow ID of the best palmar location to access the joint
14
Q
describe the arthro portal in the palmar DIP joint
A
A 5-mm skin incision is made over the lateral/medial aspect of the palmaro/plantaroproximal pouch, axial to the collateral cartilage and the neurovascular bundle and abaxial to the DDFT
15
Q
after the portal of athro in the palmar approach is made explain how do you incert the slee and the blunt obturator?
A
conical obturator is introduced parallel to the palmar/plantar aspect of the second phalanx towards the apex of the frog with the distal limb in mild passive flexion
16
Q
which structures can you evaluate in the distal joint in the palmar aspect?
A
- midsagittal ridge of the dorsal articular border of the navicular bone,
- the entire proximal border of the navicular bone
- the medial and lateral aspects of the joint
- collateral sesamoidean ligaments
16
Q
describe the portal ofr the novel lateral/medial approach to the DIP s
A
The skin incision is placed in a palpable concavity approximately 5 mm proximal to the proximal limit of the collateral cartilage of the phalanx and approximately 5 mm palmar/plantar to the palpable palmar/plantar aspect of the second phalanx. Then a stab incision with a No. 11 scalpel blade is used to incise the joint capsule
17
Q
The conventional palmar/plantar approach of the DIP may result in inadvertent penetration of which structures?
A
- Digital flexor tendon sheath
- Navicular bursa
17
Q
Beside the palmar/plantar approach what approach can you use to decrease the risk of inadvertent penetration of the DFSHEATH and navicular bursa?
A
The novel lateral/medial approach to the DIP
17
Q
Palmar or plantar digital neurectomy can be performed in which positionS?
A
standing
dorsal recumbency
lateral recumbency
18
Q
describe the inseriton of the conical obturator in the lateral/medial approachh
A
conical obturator is inserted parallel and adjacent to the palmar/plantar aspect of the second phalanx, aiming approximately 15 degrees distally to a point 1 cm below the contralateral coronary band
18
Q
Palmar/plantar igital neurectomy is advised in which cases?
A
navicular diseaseDDFT core or linear lesions (better for dorsal border lesion because core or linear do not last long without lameness despiste the neurectomy)
18
Q
A
Figure 91-64. Lateromedial radiographic view of subluxation of the DIP joint that occurred after palmar digital neurectomy.
18
what is the most common technique used for nerve transection?
guillotine technique
18
what are the complications of palmar/plantar neurectomy
Neuritis and neuroma formation particularly in the proximal stump
Rupture of the DDFT
Subluxation of the coffin joint can occur specially if it was compromissed before
18
in cryoneurectomy frozen to as low as
-30ºC transcutaneously
18
what is the disadvantage of palmar/plantar neurectomy?
Reinnervation can occur when the severed nerve endings reestablish contact with each other (Figure 91-63) in the 6 months postop
19
what are the nerve ends techniques ? list them
1. electrocoagulation
2. guilhotine
3. epineral capping (insert the nerve into a hole drilled into the proximal phalanx
4. ligate the nerve
5. cryoneurectomy frozen to as low as -30ºC
6. injection of cobra benom
7. Carbon dioxide laser treatment
20
Which technique has been described as reducing the development of neuromas?
carbon dioxide laser treatment
21
What are the methods of detecting a neurectomy, why?
animal welfare legislation and equine sports associations (e.g., the International Equestrian Federation [FEI]) prohibit horses that have had a digital neurectomy from competing in official events
22
vast majority of digital neurectomies is carried out in the
forelimbs
23
mention the 4 surgical approach for the neurectomy
1. Palmar Digital Neurectomy in the Pastern Region Using One Skin Incision
2. Palmar Digital Neurectomy in the Pastern
Region Using Two Small Incisions—
Pull-Through Technique
3. Repeated Palmar Digital Neurectomy
4.High Lateral and Medial Palmar Neurectomy
24
describe the surgical technique in details of Palmar Digital Neurectomy in the Pastern Region Using One Skin Incision
DR
Limbs tied to the ceiling -asepsis + clipping
palpate nerve - 4 cm incision made in pastern region directly over nerve
Perineural anesthesia proximal to the site of neurectomy
Ligament of ergot is ID and split longitudinally allow access to neurovascular bundle
isolate nerve from artery
Neurotomy proximally first and than distally with removal fo severed piece
closure of subcut + superificial fascial layer + ligament of the ergot continuous suture - skin with simple interrupted
OTHER TECHNIQUE preferred by authors small stab incision about 1 to 1.5 cm in length at the mid-pastern region. The nerve is isolated palmar to the artery and elevated to the level of the skin by applying tension. Subsequently the nerve is transected at the proximal aspect of the incision and, after applying considerable tension to the elevated nerve, the distal transection is made as far distally as possible. Skin closure is routine in two layers. This technique allows the removal of 2 to 3 cm of nerve
25
describe the surgical technique in details of Palmar Digital Neurectomy in the Pastern
Region Using Two Small Incisions—
Pull-Through Technique
2 skin incisions: 1 proximal pastern to MCP joint transition + 1 distal transition from pastern to bulb of heel
subcut dissected longitudinally with Mosquito forceps
Separate nerve from artery
Nerve is freed prox and distally and pulled with mosquito to ensure max exposure and resect No 15 scalpel blade
incisions are sutured routinely 2-0 non absorbable
26
describe the surgical technique in details of repeated palmar digital neurectomy
a long incision is usually made so that the nerve can be adequately isolated. This procedure is often more difficult than the initial operation because the nerve is generally very closely attached to the artery. Only the neuroma and the distal part of the proximal nerve stump should be removed. Skin closure and aftercare are the same as for the other neurectomy procedures.
27
describe the surgical technique in details of High Lateral and Medial Palmar Neurectomy
DR
incision proximal to the DFTS as the nerve is easier to locate here immediately proximal to the DFT and between DDFT and suspensory ligament on lat and med aspects of the metacarpus
28
29
30
The advantages of Palmar Digital Neurectomy in the Pastern
Region Using Two Small Incisions—
Pull-Through Technique are
1. the small size of the skin incisions,
2. short surgery time,
3. low incidence of neuroma formation
31
what is always seen in the proximal aspect of the previous surgical field in repeated palmar digital neurectomy?
Small neuromas are always seen in the proximal aspect of the previous surgical field. These nodules can be easily palpated in horses that have had a neurectomy. Sometimes the regrown nerve is surrounded by a large amount of scar tissue, which renders its isolation more difficult.
32
what is the goal of high lateral and high medial palamar neurectomy?
The goal of high lateral and medial palmar neurectomy is to disrupt afferent and efferent nerve tracts proximal to the division into palmar and dorsal branches to prevent pain sensation from chronic disease processes innervated by the dorsal branches of the lateral and medial palmar nerve.
33
the high lateral and medial palmar neurectomy are usually carried out...
proximal to the digital flexor tendon sheath (DFTS) because locating and removing the nerve is easy in this location
34
The skin is incised immediately proximal to the DFTS and between the DDFT and the suspensory ligament on the lateral and medial aspects of the metacarpus. The nerve is located, isolated, and removed. Aftercare is the same as for the other techniques.
35
What does navicular syndorme or diease refers to?
Navicular disease refers to a degenerative disorder that involves the DSB and its surrounding structures.
36
What is the treatment of navicular disease?
There is no actual cure for navicular disease. Its management concentrates on abolishing the clinical signs. Nonsurgical management and surgical management
37
List the management strategies for navicular disease
1. corrective shoeing
2. NSAIDs
3. vasodilators (isoxsuprine or metrenperone)
4. IA hyaluronan with or withou cortico into DIP joint or navicular bursa
5. Bisphosphonate tiludronate
6. clodronate disodium
38
name 2 vasodilators for navicular syndrome
isoxsuprine or metrenperone
39
what does the bisphosphonate tiludronate do?
it si a drug developed to inactivate osteoclast activity, has shown positive results in the treatment of navicular disease in horses with lameness of less than 6 months duration.1
40
what is the other option for IM injection of biphosphonate?
Clodronate disodium (Osphos, Dechra Veterinary Products, USA) is a nonamino, chloro-containing bisphosphonate for intramuscular injection.
41
what therapy has been used in humans and proposed for horses with intraosseous pressure in the navicular bone?
benwopyrone to reduce high protein edema
42
Surgical treatment of navicular disease is associated with succeful outcome?
no, none
43
what are the 3 surgical technqiues for navicular bone treatment?
1. navicular suspensory desmotomy,
2. palmar digital neurectomy,
3. periarterial sympathectomy
44
What are the supporting ligaments of the navicular
proximal: collateral sesamoidean ligaments (CLSs)
distal: impar ligament
45
The suspensory ligaments of the DSB are broad, elastic structures containing an abundance of ____ (2w)
nerve fibers
46
The suspensory ligaments of DSB originate at the dorsodistal aspect of the ________ ___________(2w) and insert primarily on the ______ _________(2w) of the DSB (Figure 91-69, A).
They originate at the dorsodistal aspect of the proximal phalanx and insert primarily on the proximal border of the DSB (Figure 91-69, A).
47
A branch of each ligament, the chondrosesamoidean ligament, also inserts on the axial surface of the adjacent ________ __________(2w) and the _______ ___________ (2w) of the distal phalanx.
a branch of each ligament, the chondrosesamoidean ligament, also inserts on the axial surface of the adjacent collateral cartilage and the palmar process of the distal phalanx.
48
Figure 91-68. Illustration of the supporting ligaments of the distal sesamoid bone (palmaromedial view). a, Collateral distal sesamoidean ligament; b, chondrosesamoidean ligament; c, impar ligament; S, distal sesamoid bone.
49
cribe the surgical transection of collateral sesamoidean ligaments (CSLs)
**GA -DR **
An E**smarch bandage** is applied as a tourniquet proximal to the MCP joint.
A** 4-cm vertical incisio**n is made **midwa**y between the **common digital extensor tendon** and the d**istal eminence of the proximal phalanx**, from the level of this eminence to the coronary band (see Figure 91-69, B). The incision continues deeper through the subcutaneous fascia to permit ID and isolation of the coronary plexus (see Figure 91-69, C) on the **proximal margin of the collateral cartilage**. Dissection axial to the cartilage allows **identification of the dorsal margin of the CSL. **Mosquito forceps are passed in a dorsopalmar direction under the CSL to elevate the ligament, and a No. 11 scalpel blade is used to transect it (see Figure 91-69, D). The subcutaneous tissues are closed in a simple continuous suture pattern using USP size 2-0 absorbable suture material. Skin closure is routine. The opposite CSL in the same limb and the ligaments of the opposite limb are transected using the same technique.
50
What is the postoperative care of CSL surgery
protective bandages for 10 days until the sutures or staples are removed. Hand walking should be initiated soon after surgery and continued for 3 weeks. initiated soon after surgery and continued for 3 weeks.
51
Postoperative complications of CSL desmotomy
rare but include
1. wound dehiscence,
2. infection,
3. local swelling
4. postoperative scarring.
52
a review of 118 horses suffering from navicular syndrome and were treated with CSL desmotomy, ___% were sound at 6 months, and ___% were still sound after 36 months
a review of 118 horses suffering from navicular syndrome and were treated with CSL desmotomy, 76% were sound at 6 months, and 43% were still sound after 36 months
53
All of the following conditions were associated with a diminished response mention them
1. flexor cortex defects
2. proximal border enthesiophytes
3. mineralization of the DDFT
4. medullary sclerosis
54
which cases are prone to poor prognosis for CLS desmotomy?
Horses with clinical signs of more than 1-year duration had a poor prognosis
55
What horses are contra-indicated to do CSL desmotomy and which ones are indicated?
The procedure is NOT recommended in horses with:
1. inflammatory disease of the DIP joint and the navicular bursa,
Recommended in horses with new bone growth at the site of insertion of the CSLs (enthesiophytes) are considered excellent candidates for this surgery.
56
Describe the surgical approach periarterial sympathectomy
10-cm skin incision is centered over the lateral and medial proximal sesamoid bones. The subcutaneous tissues and fascia are carefully transected and the neurovascular bundle is identified. The artery and vein are isolated from the perivascular tissues and adventitia over the entire length of the surgical site. The nerve is isolated from the surrounding tissues as well. Inadvertent trauma to the vessels and nerve should be avoided at all costs. The dissection strips the sympathetic nerve supply of the vessels, which results in prolonged vasodilation. The subcutaneous tissues and the skin are closed in routine fashion
57
Figure 91-69. Illustration of the desmotomy procedure of the collateral distal sesamoidean ligament. (A) Overview of the anatomic structures. (B) Location of the skin incision over the ligament. (C) After the skin is incised, the ligament can be seen underneath the superficial vessel. (D) The ligament is isolated, elevated above the skin incision, and transected.
58
what does consist the perivascular sympathectomy and fasciolysis?
59
What is the % of success in horses treated with perivascular sympathectomy and fasciolysis?
In a review of 79 horses with navicular syndrome that was treated with perivascular sympathectomy and fasciolysis, 73% became sound and returned to work. The mean duration of follow up was 23.6 months
60
What characterizes laminitis?
Breakdown of the connective tissue suspensory apparatus of the distal phalanx inside the hoof wall.
61
What happens when the laminar attachment is unable to support the distal phalanx?
The distal phalanx starts to displace.
62
When is laminitis considered chronic?
When the initial signs of displacement become apparent.
63
What is the relationship between distal phalanx movement and laminae damage?
The degree and speed of movement are directly related to the severity of damage to the laminae.
64
What diagnostic tool is most useful for laminitis?
High-quality radiographs.
65
Which radiographic projections are recommended for laminitis diagnosis?
Lateromedial and dorsopalmar (horizontal) projections.
66
What is the most important factor affecting the outcome of equine laminitis?
The severity and extent of the initial damage to the internal anatomy of the foot.
67
How is laminitis diagnosed?
Based on clinical signs and radiographic examination
68
What are the main components of laminitis treatment?
Dietary management, medical treatment, soft bedding, and hoof care.
69
What is the aim of corrective shoeing and trimming in laminitis treatment?
To reduce stress on the damaged lamellae by minimizing forces causing distal phalanx displacement.
70
What is deep digital flexor tenotomy used for?
A salvage procedure for horses with chronic refractory laminitis.
71
What are the conditions that respond favorably to deep digital flexor tenotomy?
Foundered horses with persistent draining tracts, osteomyelitis, or excessive heel growth.
72
What is the biomechanical rationale behind deep digital flexor tenotomy?
To reduce forces pulling the distal phalanx and decrease shearing stresses on the lamellae.
73
How does deep digital flexor tenotomy help the hoof?
It reduces pressure exerted by the apex of the distal phalanx and allows derotation with orthopedic shoeing.
74
At which two levels can deep digital flexor tenotomy be performed?
Midmetacarpal and pastern levels.
75
Why is the midmetacarpal level preferred for deep digital flexor tenotomy?
It is easier to perform, done on a standing horse, and has lower risk of postsurgical infection.
76
What is a key advantage of midmetacarpal over pastern tenotomy?
It does not invade the digital tendon sheath and leaves some support to the DIP joint.
77
Why should pastern tenotomy be reserved for specific cases?
It requires general anesthesia and is used when a second tenotomy is needed.
78
What type of shoeing is recommended before deep digital flexor tenotomy surgery?
Heel extension shoeing to stabilize the foot and prevent postoperative complications.
79
What concept can be applied instead of classical heel extensions in shoeing management?
Derotation shoeing.
80
What is the condition of "foundered" horses that respond to DDFT tenotomy?
Horses with persistent draining tracts from osteomyelitis and excessive heel growth may respond well to the procedure.
81
What risks are associated with performing DDFT tenotomy in the pastern region?
Horses with persistent draining tracts from osteomyelitis and excessive heel growth may respond well to the procedure.
82
What type of anesthesia is used for a midmetacarpal approach?
Local anesthesia through a high palmar ring block.
83
Where is the incision made during the midmetacarpal approach?
Over the lateral aspect of the DDFT, centered at the junction of the proximal and middle third of the metacarpus.
84
What is the function of the assistant during the midmetacarpal tenotomy procedure?
To lift the limb off the ground to relieve tension on the DDFT.
85
Why must care be taken when elevating the DDFT?
To avoid transecting the neurovascular bundle located medially.
86
What is used to transect the DDFT during the midmetacarpal approach?
A scalpel blade.
87
How much separation of the tendon ends occurs after complete transection in the midmetacarpal approach?
1 to 3 cm.
88
What is an alternative technique for midmetacarpal tenotomy?
Blind transection of the DDFT with a blunt bistoury while the horse is weight-bearing.
89
What is the risk associated with the blind tenotomy technique?
Concomitant transection of the neurovascular bundle.
90
What type of suture material is used for closing the subcutaneous tissues in the midmetacarpal approach?
Absorbable monofilament suture material.
91
How is the skin closed after the midmetacarpal approach?
With stainless steel staples.
92
What position is the horse in during a pastern approach?
Lateral recumbency under general anesthesia.
93
Where is the incision made in the pastern approach?
Along the palmar midline of the pastern, 1 cm proximal to the bulb of the heel.
94
How much separation of the tendon ends is observed after a pastern tenotomy?
6 to 10 cm.
95
What is the minimum period for bandage maintenance post-surgery?
6 weeks.
96
What is administered for postoperative pain management?
NSAIDs.
97
What kind of shoe is used postoperatively for horses after tenotomy?
A heel extension shoe for 6 to 8 weeks.
98
What common complication can occur post-tenotomy?
A mild degree of hyperextension of the DIP joint.
99
When do most horses show initial improvement after surgery?
Within 2 to 3 days.
100
What complications can develop from chronic pain after surgery? NAme 3
Osteoarthritis,
chronic infection,
or a flexural deformity of the MCP joint.
101
What percentage of horses were alive 6 months after DDFT tenotomy, according to a study of 35 horses?
77%
102
describe in detail the surgical approach of midmetacarpal tenotomy of DDFT
Standing
Esmarch
After aseptic preparation of the limb and appropriate draping, a vertical incision through the skin, subcutaneous tissues, and paratenon is made directly over the lateral aspect of the DDFT, centered at the junction of the proximal and middle third of the metacarpus(Figure 91-70, A). With the help of curved Kelly forceps, the DDFT is separated from the neurovascular bundle (see Figure 91-70, B), the accessory ligament, and the superficial digital flexor tendon (SDFT). The DDFT is elevated from the incision (see Figure 91-70, B). During this part of the procedure, an assistant should lift the limb off the ground to relieve the tension on the DDFT. Care must be taken to avoid elevating the neurovascular bundle located medially and inadvertently transecting it together with the tendon. The elevated tendon is subsequently transected with the scalpel blade. An immediate separation of the ends by 1 to 3 cm is usually noted after complete transection of the tendon.
103
Figure 91-70. Illustration of the deep digital flexor tenotomy procedure in the midmetacarpal region. (A) Location of the surgical site on the lateral aspect of the limb. (B) The DDFT is separated from the neurovascular bundle. (C) The isolated DDFT is elevated above the incision and transected. a, Neurovascular bundle; b, DDFT.
104
Figure 91-71. Illustration
of the deep digital flexor tenotomy procedure in the midpastern region. (A) Location of the surgical site. (B) The
skin, subcutaneous tissues (c),
and tendon sheath (b) are sharply transected. (C) The DDFT (a) is elevated above the incision and sharply transected.
105
describe in detail the tenotomy DDFT pastern approach
GA- LR
3-cm vertical skin incision is made along the palmar midline of the pastern region, 1 cm proximal to the bulb of the heel (Figure 91-71, A). The skin, subcutaneous tissues, and DFTS are incised, and the DDFT is exposed, elevated, and transected (see Figure 91-71, B and C). The amount of separation of the tendon ends is greater after tenotomy at this level (6–10 cm) because there are no attachments to the distal tendon other than the insertion site to the distal phalanx.155 Closure of the tendon sheath, subcutaneous tissues, and skin is routine.
