Chapter 99 - Tarsus Flashcards
1
Q
Which ligament maintains the two bones of the tarsus in close proximity in the talocalcaneal joint?
A
Intertarsal ligaments
2
Q
Which joint of the tarsus is mainly responsible for its movement during ambulation and weight bearing?
A
Tarsocrural
3
Q
For diagnostic and therapeutic purposes, which joints are often injected in the tarsus?
A
TMT and DIT
4
Q
What is the special relationship of the facets in the talocalcaneal joint that prevents motion?
A
they have strong interosseous ligament
5
Q
Which tendon spans the entire dorsal tarsal region and is maintained by retinacula?
A
LDE
6
Q
What forms the cranial part of the reciprocal apparatus in the tarsus?
A
Fibularis (Peroneus) tertius tendon
7
Q
What bursa is located between the superficial digital flexor and the gastrocnemius tendon proximally and distally?
A
Intertendinous calcaneal bursa
8
Q
What is the function of the tarsus in weight bearing?
A
To transform axial loading into oblique forces
9
Q
Where does the tendon of the medial digital flexor muscle traverse within the tarsal region?
A
Medially
10
Q
What ensures that when one of the major joints of the rear limb is flexed, all others flex?
A
Intact reciprocal apparatus
11
Q
Which joints show communication after injections in the tarsus, potentially affecting medication effects?
A
Distal intertarsal and tarsometatarsa
12
Q
What percentage of joints showed communication between the TMT and DIT joints in a study?
A
38%
13
Q
What are the joints most affected by OA?
A
TMT and DIT
14
Q
vWhat are the poor conformations that predispose to OA?
A
Bowlegged and sickle-hocked conformation
Dysmature foals with crushing of central and 3rd metatarsal bone
15
Q
What is the most common clinical sign of OA in TMT and DIT?
A
Lameness + toe dragging + short cranial phase of the stride
16
Q
How to perform the diagnosis?
A
Lameness work up and many times:
*Lameness can be excerbated with inside limb in tight circles
*Flexion tests often positive
*Check shoes for uneven wear
17
Q
What are the radiographic findings in OA of hock?
A
Common findings:
Periarticular enthesophytes
Periosteal new bone formation
*Subchondral bone lysis and/or sclerosisDecreased corticomedullary demarcationNarrowing or loss of joint space
*Spur at 3rd metatarsal bone is frequent
*Early changes occur
18
Q
The medial and lateral collateral ligaments of the tarsus each consist of two
ligaments:
A
long and a short ligament.
19
Q
what are the connections of long collateral ligament
A
long collateral ligaments
connect the distal tibia to the proximal metatarsal region,
but they also have attachments to the talus and small tarsal
bones
20
Q
what are the connections of short collateral ligament
A
short collateral ligament consists of a superficial,
middle, and deep part and originates from the medial or lateral
malleolus, respectively, cranial to the origin of the long collateral
ligaments, and attaches to the talus and calcaneus
21
Q
short collateral ligaments are tense in
A
flexion and loose in extension
22
Q
The tarsus is composed of five joints, name them
A
the tarsocrural (TC),
proximal intertarsal (PIT), distal intertarsal (DIT), tarsometatarsal
(TMT), and talocalcaneal (TCa) joints
23
Q
How many joints of tarsus are immobile?
A
4
24
Q
In a study the communication btw TMT and DIT was %, TMT % DIT and PIT with % had communication btw DIT joint and tarsal canal
A
100% TMT and DIT
DIT and PIT 2%
14% DIT and tarsal canal
25
The fibularis tertius tendon is penetrated by the tendon of the
tibialis cranialis muscle, which then divides into three branches, the medial, middle, and lateral branches, before inserting on the central, third, and fourth tarsal bones as well as the proximal metatarsal region
26
medial branch is better known as the
cunean tendon, which at one time was thought to be responsible for the development of spavin
27
The gastrocnemius muscle and tendon form the
caudal part
28
The superficial digital flexor tendon is attached to the abaxial aspects of the calcaneus via the medial and lateral retinacula and continues distad to the
digit
29
voluminous intertendinous calcaneal bursa is located between the superficial digital flexor and the
gastrocnemius tendon proximally, and between the superficial digital flexor tendon and the long plantar ligament distally.
30
What are the treatments for distal intertarsal joints (medical and sx)?
1) Corrective shoeing - wider outside branch
2) Extracorporeal shcokwave therapy (middle high energetic 0.2-0.4 mJ/mm2) 2 to 3 s every 3 w
3) Medical management with steroids, anti-inflammatories
4) surgical management
4.1 Cunenan tenectomy
4.2 Wamberg technique
4.3 Laser facilitated ankylosis
4.4 Arthrodesis with drilling
4.5 Arthrodesis with LCP T plate
4.6 Ethanol injection
31
What does corrective shoe do to the medial patellar ligament and medial side of the tarsal joint? MT?
Aleviates tension to the medial patellar and tarsal joint
Increases pressure of MTP
32
A - subcutaneous bursa
B - intertendinous bursa
C- gastrocnemius bursa
33
Dorsoplantar flexed view - skyline
34
Figure 99-14. Graphic illustration of the arthroscope portal site for examining the plantar pouch and visualizing the plantar aspect of the trochlear ridges of the distal tibia. The arthroscope is placed contralateral, and the instrument is placed ipsilateral to the lesion. a, Long digital extensor tendon; b, lateral digital extensor tendon; c, deep digital flexor tendon.
35
Figure 99-1. Graphic illustration of a lateral (A), dorsoplantar (B),
plantarodorsal (C), and medial (D) view showing the anatomic structures
associated with the tarsal region. a, Distal tibia; b, talus; c, calcaneus; d,
third metatarsus (MTIII); e, MTIV; f, long digital extensor muscle and
tendon; g, lateral digital extensor tendon; h, lateral digital flexor muscle
(together with “v” form the deep digital flexor tendon); i, soleus tendon;
j, Achilles tendon; k, superficial digital flexor tendon; l, short lateral collateral
ligament; m, long lateral collateral ligament; n, plantar ligament; o, long
part of the medial collateral ligament; p, medial part of the tibialis anterior
tendon (cunean tendon); q, middle part of the tibialis cranialis tendon;
r, branch of the fibularis tertius tendon; s, medial digital flexor tendon;
t, medial plantar ligament between the talus and calcaneus; u, short part
of the medial collateral ligament; v, tendon of the tibialis caudalis muscle;
w, fibularis tertius muscle; x, main branch of the fibularis tertius tendon.
36
Figure 99-1. Graphic illustration of a lateral (A), dorsoplantar (B),
plantarodorsal (C), and medial (D) view showing the anatomic structures
associated with the tarsal region. a, Distal tibia; b, talus; c, calcaneus; d,
third metatarsus (MTIII); e, MTIV; f, long digital extensor muscle and
tendon; g, lateral digital extensor tendon; h, lateral digital flexor muscle
(together with “v” form the deep digital flexor tendon); i, soleus tendon;
j, Achilles tendon; k, superficial digital flexor tendon; l, short lateral collateral
ligament; m, long lateral collateral ligament; n, plantar ligament; o, long
part of the medial collateral ligament; p, medial part of the tibialis anterior
tendon (cunean tendon); q, middle part of the tibialis cranialis tendon;
r, branch of the fibularis tertius tendon; s, medial digital flexor tendon;
t, medial plantar ligament between the talus and calcaneus; u, short part
of the medial collateral ligament; v, tendon of the tibialis caudalis muscle;
w, fibularis tertius muscle; x, main branch of the fibularis tertius tendon.
37
Figure 99-3. Graphic illustration of the injection site for the distal intertarsal (DIT) joint. The DIT joint is injected medially in the proximal aspect of the space that exists between the central tarsal bone (e), third tarsal bone (d), and fused first and second tarsal bone (c). The entrance to this space can often be felt with firm palpation and is found at the distal border of the cunean tendon (a), approximately 2 cm caudal to a vertical line extending distad from the medial malleolus. The location for needle entry can also be located along a line between the distal tubercle of the talus (b) and the palpable space between the second metatarsus (MTII) (f) and MTIII, where it intersects the cunean tendon.
38
Figure 99-2. Marked enlargement at the dorsomedial aspect of the distal tarsal region (arrows) in a horse suffering from osteoarthritis of the distal two tarsal joints (bone spavin). Excessive new bone formation is responsible for this appearance.
39
Figure 99-5. DLPMO radiographic view of the tarsus. There is an advance stage of ankyloses in the TMT and the DIT joints. The needle is inserted in the TMT joint.
40
Figure 99-5. DLPMO radiographic view of the tarsus. There is an advance stage of ankyloses in the TMT and the DIT joints. The needle is inserted in the TMT joint.
41
Figure 99-4. DLPMO radiographic view of the distal tarsal joints showing periosteal new bone formation, subchondral bone lysis and sclerosis, reduced corticomedullary definition, and narrowing or loss of the joint space.
42
Figure 99-6. Lateromedial radiographic view of the tarsal region of a 2-month-old foal that was born with incomplete ossification. The central tarsal bone is partially collapsed dorsally. This foal is at high risk to develop juvenile osteoarthritis.
43
Figure 7.23(b) Dorsoplantar (fl exed) view of the same hock
as Figure 7.23a. Lateral is to the right. Note the irregular
contour of the surface of the sustentaculum tali (arrow) over
which the deep digital fl exor tendon passes, and the poorly
defi ned opacities in the soft tissues medial to the calcaneus.
44
Figure 7.23(a) Plantarolateral-dorsomedial oblique view of a
hock. There is considerable modelling of the sustentaculum
tali (arrow) which was associated with distension of the tarsal sheath and severe lameness.
45
Figure 99-7. Positive contrast arthrogram after injection into the TMT joint, showing communication of the tarsometatarsal joint with the proximal intertarsal and tarsocrural joints and the extensor digital sheath
46
Describe cunean tenectomy
Under sedation + local anesthesia
▫Decreases rotational forces on the tarsus that occur when cunean tendon tightens (obliquely)▫V shape line block from chestnut to saphenous v.
▫4 cm vertical skin incision over tendon5 cm dorsal to chestnut
▫4cm tendon removed w/ n.15 scalpel bladeskin sutured
▫Compression bandage
▫Sutures removed 14th day
Usually performed with LCP T plates
*Stall rest 12 days + limited hand walking*Walking increased after suture removal*3weriding*Full work at 6 wks
47
Describe Wamberg technique
Complements cunean tenotomy
▫Grid like incisions over medial aspect of the tarsus down to bone
▫Performed ar 3.5 mm intervals▫
Completes neurectomy of this region ▫Abandoned technique
48
Driiling ankylosis mention the landmarks. Be specific
Neodymium:yttrium aluminum garnet or (Nd :YAG) or diode laser
LR with acess to medial side or DR if bilateral
After routine preparation of the surgical site, a **3-cm vertical skin incision** is made on the **dorsomedial aspect** and **centered over the TMT and DIT joints.** The sites for drill bit entry are **midway between** a line extending from the **groove between** the **proximal MTII and MTIII**,** and the **most dorsal **aspect of the **distal tarsus** (at the level of the TMT and DIT joints) (Figure 82-22). This is **adjacent** to the **plantar margin of the saphenous vein**, which has to be **displaced dorsally to avoid iatrogenic trauma.** Placement of a Penrose drain around the vein facilitates its manipulation during the surgical procedure. The** TMT and DIT joints** are identified with **hypodermic needles** using intraoperative **radiographs or fluoroscopy.**
A **4.5-mm drill bit** is passed into the joint space in **three directions from a single entry point** on the **dorsomedial aspect of the tarsus**, creating a f**an-like pattern of holes.** The tracts are best drilled in pairs (TMT and DIT): first, a **20-mm-long tract** is directed toward the **most lateral palpable extremity of the MTIV; second, a 20-mm tract angled 30 degrees to the first in a plantar direction; and third, a 35-mm tract angled 30 degrees to the first in a dorsal direction. For intraoperative imaging, it is important to orient the** x-ray beam perpendicular** to the drill tract and to angle as necessary in a distal-to-proximal direction to bring the joint margins into convergence. The **number of images can be reduced if two drill** bits are used and tracts in the TMT and DIT joints are imaged simultaneously.
49
Is the cunena tenectomy good?
cunean tenectomy has been debated, but there are no controlled clinical studies or experimental evidence in the literature (83% improvement by owners). Today, cunean tenectomy as a sole procedure is rarely performed. It is, however, performed together with an arthrodesis using locking compression plate (LCP) T-plates (see later and Chapter 82).
50
what is the theory behind the laser technique for arthrodesis?
The theory behind this technique is that by superheating and vaporizing synovial fluid, chondrocyte death should follow
51
Figure 82-22. Graphic illustration of the drilling technique for tarsal arthrodesis. The sites for drill bit entry are midway between a line extending from the groove between the proximal MTII and MTIII, and the most dorsal aspect of the distal tarsus (at the level of the TMT joint and DIT joint). Three diverging drill holes are made along the articular surfaces of the distal tarsal joints using intraoperative imaging.
52
was the average destruction of joint surface with drilling in %?
The average destruction of joint surface was 18.0% (14.5%–23.8%) for the proximal MTIII and 21.7% (15.1%–30.4%) for the proximal third tarsal bone, respectively
53
what you have to be careful when drilling the DIT and TMT?
Drilling too deeply may lead to penetration of the tarsal canal, resulting in unnecessary periosteal reaction or profuse hemorrhage from disruption of the perforating branch of the **cranial tibial artery**
54
Hoaglund et al, 2019 Comparing the clinical success rate of dorsolateral approach to the medial approach for injection of the centrodistal joint in the horse concluded that a high percentage of injections end up perivascular. What %?
65% resulted in extensive perivascular subcutaneous contrast deposition after infiltration into tarsal canal. Dorsalt approach was equivalent to teh medial approach when tradional tx
Radiographic guidance improves medial approach but not lateral approach
55
US assisted injection of the centrodistal joint in the horse by Samson and Russell EVJ 2020 what was the accuracy injecting?
Had 70% of accuracy injecting
56
Name the medication you could administer in the joints
Triamcinolone acetatehigh motion joints , VS. methyl prednisolone acetate low motion joints
*44% used 18 - 40 mg of triamcinolone acetate as the total body dosage
*Hyaluronan & polysulfated glycosaminoglycan (PSGAG; Adequan ) are used to improve joint environment and reduce inflammation in high motion joints
*Although hyaluronan was frequently combined with corticosteroids, PSGAGs were primarily injected IV not that effective (compared to steroids)
57
You should be careful during the drilling preparation by placing a penrose why?
- CAUTION: adjacent to the plantar margin of the saphenous vein . The latter has to be displaced dorsally to avoid trauma - Placementof a Penrose drain
58
What is the prognosis for surgical arthrodesis?
Favorable
REturn in 66-85% for DIT and TMT
59
What is the mechanism of action of ethyl alcohol?
Mechanism of action through nonselective protein denaturation and cellcytoplasm precipitation and dehydration
- Neurolytic results in a sensory innervation blockade at the intraarticular level
- Disrupts cartilage matrix , causes necrosis of chondrocytes and facilitates arthrodesis
60
Prognosis for ethanol injection
50% normal horses injected w 70% ethanol and radio fusion in 4mo is 94%
61
After surgical ankylosis of TMT and DIT joints the horses are free of lameness in how much time?
In 3 to 4 months
62
What is the postoperative treatment following arthrodesis of the TMT and DIT joints
Hand walking exercise is started 3 to 4 weeks after surgery. Administratration of AINS and AB
63
OA of talocalcaneal joint the clinical signs are not specific, waht are the best methods for diagnosis?
Radio and scintigraphy
64
When do you judge if the TMT and DIT ankylosis worked?
12 months after procedure
65
what is the prognosis for undergoing arthrodesis of the DIT and TMT joints? does PIT have influence?
66.7% to 85% of horses undergoing arthrodesis of the DIT and TMT joints.
Yes PIT worsens the prognosis due to communication with TC joint
66
Injection with MIA what is the prognosis?
The prognosis following chemical fusion of the distal tarsal joints with MIA is favorable.
67
When do you judge the horses with MIA tx?
Some horses show dramatic improvement in the original level of lameness **within 1 week after treatment**, even though fusion might not be apparent radiographically for 3 to 6 months
68
What is the % of success of MIA tx of the distal tarsal joints?
100%)horses had radiographic fusion of the treated distal tarsal joints, and 12 of 16 75% were free of lameness and the treatment was considered successful
69
describe in detail the surgical placement of T - plate for arthrodesis
A **3-cm longitudinal skin incision** is made at the **dorsomedial aspect** of the **distal tarsal joints,** which is consistently **adjacent to the plantar margin of the saphenous vein**. Use Penrose drain to deviate the vein.The **medial branch** of the **tibialis cranialis muscle** is then** dissected to expose the TMT and the DIT joint.** Any **exuberant exostoses** are partially **removed **with an osteotome and mallet. This facilitates identification of the joint spaces involved, provides a greater plate-bone contact area, and reduces the amount of plate contouring needed. The **PIT joint space** is identified through placement of two **hypodermic needles** or two 2-mm drill bits using intraoperative imaging technique.
**Cartilage of the TMT and the DIT joint is partially removed using the drilling techniqu**e described previously. These **holes may be filled with a bone graft plug** harvested from the proximal tibia or the tuber coxae. Placement of such a **plug, hydroxyapatite granules, or biodegradable bone cement** will enhance osseous union of the two articulations by means of spot welds.
The selected **four-hole 4.5/5.0-mm LCP T**-plate is applied **dorsomedially through the skin incision**. Minimal contouring is usually required. The T-plate is placed minimally invasively by pushing it distally between the skin and the dorsomedial aspect of MTIII. The s**crews in the MTIII are inserted through stab incisions** (Figure 82-24).
Intraoperative imaging in multiple projections is important for adequate placement of the 4.5/5.0-mm LCP T-plate (Figure 82-25). The **thread hole** for the** central hole** of the horizontal bar of the T-plate is drilled with the **4.0-mm drill bit **protected by the corresponding drill sleeve within the body of the central tarsal bone, parallel to the joint surfaces. In s**maller horses, 4.5-mm screws may be used instead of 5.5-mm screws**. In that case, a **3.2-mm thread hole** is prepared. (It is important to use **5.5-mm cortex screws whenever possible, because they resist cyclic loading better than 4.5-mm screws. Screws 4.5 mm in diameter often fail in an adult horse.)**
After **tapping the thread hole,** the **5.5-mm cortex screw** is inserted into the **central tarsal bone and tightened to compress the plate firmly onto the bone**. At this point, limited adjustment of the T-plate is still possible to align the T-bar parallel to the proximal intertarsal joint. Compression across the DIT and TMT joint is achieved by inserting a **second cortex screw **in **load position** through the **most distal stacked combi-hole in the plate into the MTIII **(Figure 82-26, A). If the DIT and TMT joints are to be fused, screws are inserted next to the T-plate across the TMT joint or across the DIT joint, respectively. The remaining plate holes in horizontal and **vertical bars are filled with LHSs** (Figure 82-27). It is possible to use **two LHSs** in the **horizontal bar** and **two in the vertical bar** to save some cost by using cortex screws in the remaining holes.
After **flushing the surgical site, **the subcutaneous tissues and the skin are closed in routine fashion. Intraoperative regional perfusion of antimicrobials is recommended.111 The surgical site is covered with a bandage.
70
what is the postoperative care of arthrodesis of TMT and DIT with T plate?
kept under a bandage for 2 to 3 weeks. The skin sutures or staples are removed 10 days after the surgery. Lameness can persist for several months. Rehabilitation must be conducted gradually over several months.
71
Figure 82-23. Graphic illustration of a tarsal arthrodesis with a four-hole 4.5/5.0-mm LCP T-plate applied dorsomedially
72
Figure 82-24. Minimally invasive approach for placement of a 4.5/5.0-mm four-hole LCP T-plate. Intraoperative regional perfusion of antimicrobials can be performed in an attempt to reduce the risk for postoperative infection in distal tarsal joint arthrodesis.
73
Figure 82-26. (A) Intraoperative DLPMO view of the 4.5/5.0-mm LCP T-plate at the dorsomedial aspect of the distal tarsal joints. Tension across the DIT joints and the TMT joint is achieved by inserting a second cortex screw in loading position in the MTIII. (B) A cortex screw is being inserted across the DIT joints to counteract rotational forces.
74
Figure 82-27. (A) Lateromedial, (B) dorsomedial-
plantarolateral, (C) dorsolateral-plantaromedial, and (D) dorsoplantar radiographs of an arthrodesis of the distal tarsal joints using a four-hole 4.5/5.0-mm LCP T-plate in a 7-year-old Warmblood mare with chronic lameness because of severe osteoarthritis.
75
Figure 82-27. (A) Lateromedial, (B) dorsomedial-
plantarolateral, (C) dorsolateral-plantaromedial, and (D) dorsoplantar radiographs of an arthrodesis of the distal tarsal joints using a four-hole 4.5/5.0-mm LCP T-plate in a 7-year-old Warmblood mare with chronic lameness because of severe osteoarthritis.
76
Conservative therapy of OA talocalcaneal joint is an option?
Unrewarding
77
describe the ligaments of TCa joint
Ligaments of talocalcaneal zone:
1. medial,
2. lateral,
3. proximal,
4. interosseous talocalcaneal
78
What are the surgical treatment of OA talocalcaneal?
Partial tibial and fibular neurectomy not recommended – poor results
▫Osteotixis also doesn’t improve
▫Arthrodesis of TCa - 3 techniques
79
Neurectomy of fibular and tibial nerves for TCa is an option?
No. Surgical treatment involving partial tibial and fibular neurectomy cannot be recommended because of the poor results
80
Conservative tx of TCa is an option? What are the tx?
Conservative therapy is usually unrewarding. Stall rest, pasture exercise, and intraarticular corticosteroids with or without hyaluronan or PSGAG did not bring about consistent improvement of the lameness.
81
Figure 99-9. Scintigraphic images (A–C) and lateromedial radiograph (D) of a horse with 3/5 lameness right hind. There is a marked radiopharmaceutical uptake in the area of the talocalcaneal joint of the right hindlimb. LM radiograph view of osteoarthritic changes located in the talocalcaneal joint (arrows).
82
Figure 99-9. Scintigraphic images (A–C) and lateromedial radiograph (D) of a horse with 3/5 lameness right hind. There is a marked radiopharmaceutical uptake in the area of the talocalcaneal joint of the right hindlimb. LM radiograph view of osteoarthritic changes located in the talocalcaneal joint (arrows).
83
Describe the surgical technique for TCa arthrodesis
GA - LR - affected limb uppermost - tourniquet optional
At the **lateral aspect of the calcaneus a slightly curved incisio**n is made from the midpoint of the bone to its distal end. The tissues are sharply divided down to the bone.
**Needle markers** are used to determine the **correct angulation** of the future **screws under fluoroscopic guidance.** Computer-assisted guidance greatly facilitates preparation of the drill holes (see Chapter 13). The drill bit is aimed toward the **plantaromedial aspect of the medial trochlear ridge of the talus**, avoiding penetration of the tarsocrural joint at the intertrochlear groove
**Two or three 5.5-mm cortex screws** are inserted in **lag fashion** across the lateral facet using routine technique (Figure 82-30). There is an adequate amount of solid bone present to achieve stable transarticular compression. By slightly diverging the direction of the screws, an increased compressive effect can be achieved. To prevent weakening of the calcaneal bone, **washers **may be applied, which negate the need for countersinking. Alternatively, the screws may be inserted through a plate contoured to the calcaneal surface. Once the screws are in place and solidly tightened, the incision is closed using routine
technique.
84
Figure 82-30. Oblique postoperative radiographic view of a talocalcaneal arthrodesis performed through three converging 5.5-mm cortex screws inserted in lag fashion across the lateral facet of the talocalcaneal joint. Washers were used in the two proximal screws to increase the contact area of the implants and reduce stress concentration at the bone–screw head junction.
85
What are the types of distal tibia fractures?
DITR fracture (rare)
Medial malleolus - trauma and avulsion
Lateral malleolus - avulsion
Trochlear ridges if the talus
86
which ligament is ruptured along with med malleolus fracture?
medial short collateral ligament
87
Can the horse have lateral malleolus fracture? is it a challenge?
Yes, usually they are comminuted
Arthroscopy can be used to remove fragments but because of the soft tissue coverage and intimate association with the joint capsule or lateral collateral ligaments, arthroscopic removal of lateral malleolar fragments is technically demanding
88
what techniques can you use for lateral malleolus avulsion fracture removal?
arthroscopy and arthrotomy
89
describe the surgical tx of arhtroscopy for avulsion fragment of **lateral malleolus**
DR - **120º** instead of the usual 90º
A**rthro portal dorsolateral** and instrument **abaxial **to the arthro portal into the dorsolateral pouch
An additional instrument portal in the plantarolateral pouch can be helpful
Framgment might need to be reduced with osteotome and mallet
90
major part of the lateral malleolus fractures are IA?
**No,** the important
point to note with fragments of the lateral malleolus is that
a relatively small portion of the lateral malleolus is actually
intraarticular; most of it is enclosed within the collateral ligaments (Arthro book)
91
Large lateral malleolus of tibia fractures expose which structures?
Large fragments frequently expose the **long lateral collateral ligament** and, on occasions, the tendon of
insertion of the **lateral digital extensor** and its synovial sheath.
92
what is the prognosis for removal of the fragments?
It was concluded that horses with fractures of the lateral malleolus have an **excellent prognosis** for return to full athletic activity following arthroscopic debridement and that arthroscopic
93
Figure 7-27 A, Dorsoplantar radiograph showing large and smaller intraarticular fractures of the lateral malleolus of
the tibia. B, External view of position of arthroscope and instrument to remove fragmentation of the lateral malleolus
of tibia.
94
What if the lateral malleolus fragments are bigger than 3 cm?
Fragments larger than 3 cm are best reattached to the parent bone using 3.5-mm cortex screws placed in lag fashion. Large avulsion fractures of the medial malleolus can be repaired with one or two 4.5- or 5.5-mm cortex screws placed in lag fashion with or without plates (Figure 99-11).
95
what is the recovery for fixation of lat malleolus of tibia fragments with 3.5 mm cortex screws in lag fashion?
Recovery after surgery of the trochlear ridges of the talus takes** 8 to 10 weeks** after arthroscopic removal of **small fragments** and** 6 to 8 months** or more if fracture repair is undertaken
96
Conservative tx for nondisplaced tibial maleolar fractures is possible?
yes it is possibel
97
Figure 99-10. Lateromedial radiograph showing a large fracture fragment including the distal intermediate ridge of the tibia (A). This fracture was fixed with two cortical lag screws across the fracture
plain (B).
98
Figure 99-11. Dorsoplantar (A) and lateromedial (B) radiograph of a large fracture fragment in the distal tibia including the medial malleolus. Arthroscopy of the tarsocrural joint shows the displacement of the fracture in the distal tibia (C). Fixation was achieved with two cortical lag screws and a LCP plate using 4.5- and 5.5-mm cortical screws (D, E)
99
Figure 99-11. Dorsoplantar (A) and dorsolateral plantaromedial oblique (B) radiographThe three most distal screws of the plate were inserted in lag fashion. Reduction of the fracture is visualized arthroscopically (F).
100
Fractures of the talus are result of what?
are almost exclusively the result of **external trauma,** such as a kick from another horse.
101
what are the clinical signs of talus fracture?
Significant effusion of the TC joint is seen with most fractures of the talus, and response to tarsal flexion is moderate to severe.
102
what radiographs should be taken for dx of TR talus fracture?
supplemented with **flexed lateromedial** and **flexed lateromedial-oblique projections** and skyline views of the trochlear ridges.
103
what are the most affected portions of the trochlear ridge in case of fracture?
The **distal aspect of the lateral trochlear ridge** (Figure 99-12) and the proximal aspect of the medial trochlear ridge are most often affected.
104
what is the preferred tx of TR fractures? describe it
Arthroscopic removal
The arthroscope portal for removing trochlear ridge lesions can be either **dorsomedial **or **dorsolateral.** The **dorsolateral portal offers better** visualization of the distal aspect of the lateral trochlear ridge, but the standard **dorsomedial portal is preferred because triangulation is better** and the surgeon can carry out a more thorough exploratory examination of the joint from a medial approach. The instrument portal is always dorsolateral and is usually slightly distal to that used for distal tibial lesions. Osteochondral defects or cartilage flaps might extend proximad along the lateral trochlear ridge, necessitating extension of the limb during surgery.
105
Describe the LTR reparation with interfragmentary compression
After the **fragment is identified **and reduced, a **glide hole is drilled** perpendicular to the fracture plane from the dorsal aspect of the ridge. After preparing the** thread hole**, a deep **countersink depressio**n is prepared in the articular surface to accept the entire screw head. Therefore, it is better to use multiple **3.5-mm cortex screws**, which have smaller heads (6-mm diameter), than to use **4.5- or 5.5-mm cortex screws** (8-mm head diameter). In large fragments, an adequate amount of solid bone is present to permit fixation. Anatomic reconstruction is a must if fixation is attempted. If this cannot be achieved, it is best to remove the fragment immediately to prevent the development of OA. Alternative fixation techniques include absorbable polydioxanone pins and cannulated screws.
106
Figure 99-12. (A) A large, slightly displaced slab fracture of the lateral trochlear ridge. (B) The fracture was repaired with three 3.5-mm cortex screws inserted perpendicular to the fracture plane. The screws were inserted from the articular surface, and the screw heads were countersunk below the surface.
(C) A 2-year follow-up revealed no osteoarthritis in the joint. The horse was successfully competing in show jumping events.
107
Figure 7-18 Diagram of position of arthroscope and instrument
during operations involving an osteochondritis dissecans lesion
of the medial trochlear ridge using arthroscopic and instrument
approaches from the same side of the joint. LDE, Long digital
extensor tendon; PT, peroneus tertius; TC, tibialis cranialis.
108
Figure 7-14 Larger osteochondritis dissecans (OCD) lesion of lateral trochlear ridge (LTR) of the talus. A, Radiograph
showing fragmentation at distal aspect and defect extending 3 cm up LTR. B, Arthroscopic view of OCD flap
delineated by cleft that probe is in. C, Use of probe to separate OCD flap and define limits. D, After removal of flap
evaluating defective tissue underneath. E, After debridement of osteochondrotic tissue down to healthy, bleeding bone
and smooth edges of cartilage, which is still attached to the bone.
109
what is a dewdrop?
Spurs or fragments associated with the distal end of the medial trochlear ridge of the talus (dewdrop lesions) are usually incidental findings and are not an indication for surgery, because they are usually extraarticular (Figure 99-13)
110
Figure 99-13. Lateromedial radiographic view showing a teardrop lesion or fragmentation originating from the distal aspect of the distal medial trochlear ridge of the talus. This finding is usually incidental and rarely has any clinical significance.
111
Figure 7-29 A, A skyline radiograph of the tarsus showing a fracture of the proximal plantar aspect of the medial trochlear
ridge (arrow) in a 2-year-old Percheron-cross filly. The fracture resulted from a kick 2 months before radiography. B, An
oblique flexed lateral radiograph projects the proximoplantar extent of the medial trochlear ridge and the fracture (arrow).
112
Fragments of the plantar aspect of throclear ridge what is the tx?
ARTHRO removal
GA -DR - limb is positioned in flexion. With the joint distended, the arthroscope portal is made in the center of the plantarolateral pouch of the TC joint. This approach provides good visualization of the most proximal aspect of the talocalcaneal articulation, the proximoplantar aspect of thelateral trochlear ridge, the plantar aspect of the intermediate ridge of the tibia, and the medial trochlear ridge. Access to affected portions of the trochlear ridge can be accomplished as the degree of flexion is modified. The instrument portal is made in the plantaromedial joint pouch using needle and visual arthroscopic guidance.
113
Figure 99-15. (A) Avulsion fracture of the lateral aspect of the distal talus with PIT articular involvement. The horse was managed conservatively with rest for 1 year and eventually fracture repair with 3.5 mm cortex screws after
114
Figure 99-15. (A) Avulsion fracture of the lateral aspect of the distal talus with PIT articular involvement. The horse was managed conservatively with rest for 1 year. (B) Marked joint distention visible in the TC and PIT joints. a, Dorsomedial pouch; b, plantarolateral pouch; c, lateral aspect of the proximal intertarsal joint. (C) Postoperative radiographic view showing the fixation of the fracture with two 3.5-mm cortex screws. Six months later, the horse competed successfully in show jumping events.
115
Figure 99-15. (A) Avulsion fracture of the lateral aspect of the distal talus with PIT articular involvement. The horse was managed conservatively with rest for 1 year. (B) Marked joint distention visible in the TC and PIT joints. a, Dorsomedial pouch; b, plantarolateral pouch; c, lateral aspect of the proximal intertarsal joint. (C) Postoperative radiographic view showing the fixation of the fracture with two 3.5-mm cortex screws. Six months later, the horse competed successfully in show jumping events.
116
Fractures of the distal lateral or medial aspect of **body of talu**s are rare, what is the tx?
**Conservative is unrewarding**, repaired with 3**.5-mm cortex screws in lag fashion** through an approach directly over the fragment. The lameness and joint distention resolved **4 months postoperatively** and the horse was returned to show jumping.
117
What are the clinical signs of DISTAL lat or med body talus fracture?
always non–weight-bearing lame and the tarsus is diffusely swollen.
118
What is the recovery treatment after arthro screw fixation?
Recovery after surgery of the trochlear ridges of the talus takes 8 to 10 weeks after arthroscopic removal of small fragments and** 6 to 8 months or more if fracture repair is undertaken**
119
prognosis for distal lat or med talus fracture?
favorable if soft tissue injury is mild
120
121
Sagital fractures of the talus are rare, what is the best method of diagnosis?
CT
122
how can you repair sagittal fractures of the talus?
with **two or three 4.5- or 5.5 mm cortex screws placed in lag fashion.**
Approach to the fracture can be either lat or medial
Arthro during procedure is useful for reduction
123
Prognosis of sagital talus fracture
favorable
124
what if the sagittal fracture is incomplete, how do you manage? (racehorses)
conservatively with rest and has good prognosis
125
what type fractures are common in calcaneus?
open infected fractures with osteomyelitis, septic calcaneal bursitis, sequestration and chronic draiange
126
what can result from major fractures of calcaneus?
displacement of the superficial flexor tendon (Figure 99-17) or can involve the sustentaculum tali.
127
diagnosis of calneal fractures are quite straightforward but what projections are important to assess?
skyline - dorsoplantar flexed of the hock is important to acess sustentaculum tali
tuber calcis
128
Figure 99-17. DLPMO radiographic view of the tarsal region of a foal (100 kg bodyweight) with a transverse fracture of the calcaneus (A).
129
Figure 99-17. DLPMO radiographic view of the tarsal region of a foal (100 kg bodyweight) with a transverse fracture of the calcaneus (A). The fracture was reduced and fixed with a lag screw across the fracture plane. Subsequently, a 6-hole LCP plate with locking screws was applied plantarolaterally (B). The foal made an uneventful recovery and the fracture healed.
130
How would you perform the correction of a transverse fracture of the calcaneus?
Transverse fractures of the shaft of the calcaneus require application of one or two **narrow 4.5-/5.0-mm LCP plates** or one broad plate placed on the plantarolateral aspect of the bone (Figure 99-17). The SDFT is reflected medially to allow placement of the plate
Recovery and maintained for **2 to 4 weeks** in a **full-limb cast** that is removed with the horse standing.
131
what is the prognosis of **transverse fracture of the calcaneus**?
Removal of the implants after fracture healing can be helpful, but the overall prognosis to return to full performance for this type of fracture is **guarded**
132
what is the treatment for a calcaneal fracture along with bursa involvement?
Poorer prognosis
Aggressive treatment including bursoscopy should be implemented as soon as possible after the injury has occurred and includes meticulous débridement of the wound, removal of fragments, curettage
of the fracture bed, lavage of the bursa, systemic and localadministration of antimicrobials until infection resolves, and placement of the limb in a cast for 3 weeks. Subsequently, a half-shell cast should be applied for an additional 3 weeks, followed by a Robert Jones dressing, provided the horse shows no signs of infection.
133
Describe how would go and remove this fragment
**Plantar pouch of TC**
The plantar pouch is **excellent to visualize also the L and M trochlear ridges** not visualized by dorsal approach
***Joint distention is critical ** & can be performed dorsally or by placing a needle in center of plantar pouch
*Skin portal is made in center of plantar outpouching with **tarsus flexed at 90** degrees
Introduction of **scope** through a **plantaro medial/plantarolateral portal **puts scope immediately **dorsal to** **tarsal synovial sheath** surrounding** DDFT & plantar to trochlea rridges **of talus Evaluation of plantar aspects of medial & lateral trochlear ridges of talus, trochlear groove,distal tibia (plantar aspect of intermediate ridge), articular portion of tendon sheath containing DDFT
Extending joint to approx 120 degrees - medial & lateral dorsalcul-de-sacs of joint can be observed more easily
More flexion an enhanced examination of proximal areas of medial & lateral trochlear ridges is possible
134
Diagram of arthroscopic field A and arthro view B of the plantar pouches of the right TC joint using plantarolateral entry
With the horse in DR the IRT is uppermost and the LTR and MTR are visible. An egress canula has been insterd in the plantaromedial cul-de-sa of the joint and used to caudally retract the DDP within the tarsal sheath
135
What if you have ti remove a fragment from the medial malleolus of the tibia?
Medialmalleolus
*Dorsomedial portal as DIRT but mademore distal
▫To minimize risk of pulling the arthroscope out of the joint during visualisationInstrument portal slightly axial and distal
136
what is the % prognosis of survival if there is a septic calcaneal bursitis and tuber calcanei is involved?
44%
137
Sustencalum tali fractures are painful?
yes the horses usually is acutely lame and usually the tarsal sheath of DDFT is affected
138
how do you diagnose sustentaculum tali fractures?
proximodistal flexed view (skyline) is the best
139
describe the surgical approaches available
Chip fracture removal can be achieved with tenovaginoscopic technique
- Although one study suggests that many of the bony lesions might be outside of the tendon sheath and are best approached directly.
- Flushing of the tendon sheath with copious amounts of fluids is indicated after chip removal and careful curettage of the fracture bed.
- The open technique of tendovaginotomy and fragment removal represents another surgical approach
140
what is the prognosis for sustaculum tali fractures?
guarded for future usefulness of the horse
141
Fractures of the small tarsal bones specially slab of the central or third tarsal bones occur in which type of horses?
racing or other high-speed events
142
What are the clinical signs of the small tarsal bones fracture?
Lameness is** initially severe, **but it diminishes over several weeks. Marked **response to hock flexion** persists over time, and persistent effusion of the TC joint is noted if the central tarsal bone is involved
143
most central tarsal bones have a consistent plane of fracture what is it?
dorsomedial to plantarolateral orientation
144
dorsomedial to plantarolateral orientation is the orientation of the fracture in the central tarsal bone. What is the ideal view?
**Dorsomedial-plantalarolateral oblique** radiographic prjection is the most useful
145
describe the orientation in detail of the sagittal slab fractures in Warmbloods
they are sagittal slab fractures that extend from **dorsally in a plantar or plantaromedial direction **and exit the plantar cortex at the plantaromedial indentation of the central tarsal bone or at the plantar indentation between its two small articular surfaces of the fourth tarsal bone
146
Fig 2: Transverse computed tomography image (bone window) of the left tarsus
of Case 1, illustrating a typical fracture configuration. Dorsal is on top, medial on
the right. A fracture line (black arrow) is running in the sagittal plane through the
central tarsal bone (os tarsi centrale; OTC). This line exits the plantar cortex in
the indentation (white arrow) between the articular surface to the fused first and
second tarsal bone (I + II) and the articular surface to the fourth tarsal bone (IV).
Note the marked sclerosis of the central tarsal bone around the fracture line,
especially in the dorsal aspect.
147
Figure 29.20 A two-year-
old
Thoroughbred with acute onset lameness after racing. It presented five days after injury, and there was
moderate distension of the tarsocrural joint. (a) DM-PLO
radiograph demonstrating a slab fracture of the dorsolateral aspect of the central
tarsal bone. (b) Transverse CT image demonstrating fracture configuration. (c) Intra-operative
DM-PLO
radiograph with needle placement to
guide repair. (d) Intra-operative
DM-PLO
radiograph following screw placement. (e) DM-PLO
radiograph 10-months
post-operatively
demonstrating fracture healing. The colt first raced five months post-operatively
and subsequently seven times with three wins and one place.
148
Fig 4: Dorsomedial-plantarolateral oblique radiograph of the right tarsus of Case
5 obtained 14 months after surgery. A 50 mm long 4.5 mm cortical screw was
inserted in lag fashion in a plantaromedial to dorsolateral direction. The implant
is intact. Mild osteophyte formation is evident at the dorsolateral aspect of the
distal intertarsal joint (white arrow). This was a common finding at long term
follow-up. No other complications are identified. In this horse, slight narrowing of
the joint space of the tarsometatarsal joint (white arrowhead) was present
preoperatively and remained unchanged over time.
149
What is the treatment for slab fractures of the central or third tarsal bones?
**Screw fixation** of slab fractures of the central and third tarsal bones is the treatment of choice (Figure 99-20).
**Toruniquet **- DR or LR - but parallel to the ground is better and the fracture is compressed using one or two** 3.5- or 4.5-mm cortex screws placed in lag fashion** through stab incisions using intraoperative radiographic or fluoroscopic control. A positive outcome for slab fractures of third tarsal bones treated by means of minimally invasive fixation techniques with a single 3.5-mm cortex screw applied in lag fashion under radiographic control has been reported.
150
what is the prognosis for central tarsal bone fixation?
It was demonstrated that **79% of the horses returned to racing**. There were no complications and all fractures healed within **4 to 6 months postsurgery.** In a smaller case series, minimally invasive fixation techniques of **central tarsal bone** fractures in nonracing horses resulted in a **very good prognosis**
151
conservative treatment for third and central tarsal bones is an option?
Conservative treatment (prolonged stall rest) has been successful, and some horses return to athletic use.83 Third tarsal bone fractures responded better to conservative treatment than central tarsal bone fractures, which would be expected because OA in the TMT or DIT joint might be better tolerated by the horses than OA in the PIT joint.80,84 However, treatment by screw fixation offers a better prognosis compared to conservative management because the risk of OA might be reduced.
152
what is the rest time after surgical intervention for central and third tarsal bones?
Horses are rested for 4 to 6 months after surgery.
153
what is the designation for a central tarsal bone that is proximo distally complete?
slab fracture
154
Figure 29.16 Transverse schematic
illustrating areas of the sustentaculum tali
which communicate with (red) or are out
with (yellow) the tarsal sheath. Source:
Adapted from McIlwraith et al. [6].
155
Kadic et al 2019 described a diagnositc needle artho of the TC in standing sedated horses what is quite helpful for the position of the surgery? What are the complications?
Custom-made splint
Moderate movement and hemarthrosis
156
Soft tissue and tendinous disorders of the tarsus: name the diferent disorders
Tears and avulsions of collateral ligaments
Tears and displacement (luxation/subluxation of SDFT
Displacement of lateral DDFT
157
What are the methods of diagnosis of soft tissue lesion in tarsus?
US exam and diagnostic arthroscopy of TC
158
What is more affected the medial collateral ligament of the lateral collateral ligament?
MEDIAL collateral ligament * involved shorttarsal collateral ligament in 48%, thelong tarsal collateral ligament in 20%, and both in 32% in an ultrasonographicstudy
Most patients have concurrent tear of joint capsule
159
What is the tx in case of capsule tear and ligament lesion?
debridement with synovial resector
160
What should you consider when waking up from GA in horses with extensive collateral ligament disruption?
Short cast
161
which ligaments are more commonly affected the medial or the lateral collateral ligaments?
The medial collateral ligaments are more commonly affected (14 of 23 cases) than the lateral ones. The collateral ligament lesions involved the short tarsal collateral ligament in 48%, the long tarsal collateral ligament in 20%, and both in 32% in an ultrasonographic study. In
162
Fraschetto AVMA et al 2023 refers in a study that most horses had single CL injury, usually the short lateral. What was the % of enthesopathies?
70.21%
163
Fraschetto AVMA et al 2023 Desmophaties were 27.9% what was the involved portion in the proximal part and distal parT?
proximal it was the insertion of SLCL
distal attachement of LMCL
164
Fraschetto AVMA et al 2023 What was the conservative treatment applied? When did the horses return to work
Stall rest for 120-180 days did not differ between groups and most horses 80% (50/32) returned to work within 6 months (61% return to higher level)
165
Dirsruption of calcaneal fibrocartilagenous flap that is formed by SDFT is associated with 3 types of dislocation of SDFT name them:
Lateral displacement w/ disruption of medial retinaculum
Medial displacement w/ disruption of Lateral retinaculum
Splitting of SDFT w/ portion lying on either side of tuber calcis
166
What is the technique of choice for diagnosis of luxation/subluxation of SDFT?
US
167
What are the treatment options luxation/subluxation of SDFT?
- Rest 4-6 months- Possible remaing mechanical lameness- Return to work possible
- Surgical repair (unrealiable)
168
EVE 2019 Federici et all mentions the outcome of conservative and surgical tx of luxations of equine SDFT from calcaneal tuber
*8 horses were treated conservatively
*Long-term follow up available for seven
- SDFTwas in an unstable dislocated position in all horses (sixl ateral and one plantaromedial)
71% performed at their intended level
169
What were the techniques used to reconstruct luxation/subluxation of SDFT??
synthetic mesh
synthetic mesh, sutures and sutures screws
sutures and suture screws
170
Describe the surgical tx luxation/subluxation of SDFT?
Dorsal or lateral recumbency to allow exposure of damaged sideof tarsal retinaculum *Curvilinear incision over plantaromedial or plantarolateral aspect of tuber calcis,edges of torn SDFT retinaculum are identified & sharply débridedif necessary
*Anchor screws or suture screws areplaced horizontally into tuber calcisat level of insertion of retinaculum
*Large diameter nonresorbable sutures such as Ethibond USP4 or FiberwireUSP2 are preplaced in a simple-interrupted pattern withbites going through abaxial aspect of fibrocartilagineous cap of SDFT & through eyelet of suture screw
*All sutures are tightened together & successively tied after completereposition of SDFT
*Ruptured ends of torn retinaculum subsequently apposed andclosed with interrupted horizontal mattress sutures of USPsize 0 monofilament absorbable material
*Finally, a synthetic mesh isfixed over repair with single interrupted sutures using nonabsorbable suturematerial going through eyelet of suture screws abaxially & through fibrocartilaginous cap of SDFT axially
*After incision is closed, limb isplaced in a full-lengthlimb cast for recovery or a hydropoolrecovery is performed
*Confinement for 4-6 months is necessary to allow sufficient fibrosis
171
dorsoplantar A and lateromedial B radiographic views of tarsal region showing suture screws inserted into the lateral and proximal aspect of the calcaneus to facilitate the repair of the ruptured retinaculum
172
What was reported as tx by in for subluxation of SDFT?
Resection of disrupted tendinoligamentous tissues and fibrocartilage via a calcaneal bursoscopy caused a stable subluxation, decreasing pain, and allowing the majority of the patients to return to function. In this study, six of seven horses with unstable SDFT’s returned to work after surgery. Two horses subsequently suffered similar injuries to their contralateral limbs 23 and 30 months after surgery. Both were managed in a similar manner and again returned to athletic function. These results seem promising and appeared to offer an improved prognosis and less complications when compared to previously reported surgical fixation techniques
173
Describe the location of the lateral digital flexor tendon and medial digital flexor tendon and what to they give and form when reunited
In hindlimb, **lateral digital flexor tendon (LDDFT) **crosses **caudomedial** aspect of tarsal region over **sustentaculum tali within tarsal sheath**
*Separate tendinous structure, **medial digital flexor (MDF)** tendon,runs **medially to tarsus** within its **own sheath**
*Both structures **merge distal to tarsus** & form **deep digital flexor tendon (DDFT)**
174
Explain in what consists the luxation of LDDFT and what is the cause?
Luxation or displacement of LDDFT is a rare congenital anomaly where the tendon is located axial to its normal position & not within groove formed by sustentaculum tali
175
What is the first clinical sign and when is the dx of luxation of the LDDFT?
recognizable clinical sign is a varus deviation of tarsus noted at 2-4 weeks after birth
176
Dorsoplantar (flexed) oblique view of the hock of a 3-week-oldThoroughbred foal with a malformed hock. Lateral is to the right. There is flatteningof the sustentaculum tali (arrow).
177
What is the tx LLDFT
Surgery to replace DDFT in its normal position & augment sustentaculum tali has been recommended **but does NOT seem feasible**, because it is very unlikely that foal will grow up to be a functional athlete
178
Figure 99-22. (A) Lateromedial radiographic view showing osseous proliferation of the distal aspect of the sustentaculum
tali. (B) Note the substantial new bone formation on the skyline view of the sustentaculum tali. These lesions are associated with chronic irritation and inflammation of the sheath of the deep digital flexor tendon
179
Chronic irritation and tenosynovitis of the DDFT tarsal sheath can be a sequela of
injury to the sustentaculum tali, intrasynovial LDDF tendon (the only tendinous structure within the tarsal sheath) or tenosynovitis of the tarsal sheath. Radiographically, new bone proliferation (Figure 99-22) can
180
what is the treatment options for DDFT tenosynovitis?
tenoscopic exploration of the pathology, and removal of any proliferative changes, fragments of the sustentaculum tali, tenosynovial masses, débridement of tendinous pathologies, and/or treatment of septic tendovaginitis. Tendovaginotomy represents an alternative approach.
181
what is important in the postop management of surgical correction DDFT tarsal sheath tenosynovitis?
After the skin incision is closed in routine fashion, a pressure bandage is applied and maintained for 3 weeks. Intratendovaginal hyaluronan 1 week postoperatively is has been recommended.
182
chronic degenerative changes of the sustentaculum tali and overlying DDF tendon have a ________ prognosis
guarded prognosis
183
Figure 99-23. DMPLO (A) and skyline (B) radiographic view illustrates chronic calcification in the deep digital flexor tendon and in its tendon sheath at the medial aspect of the tarsus.
184
The gastrocnemius is composed by
medial and lateral muscle belly
185
Gastrocnemius is a part of the caudal reciprocal apparatus together with
SDFT
186
Rupture of gastrocnemius is normal in wich situations?
Rare in adults
Common in foals associated with dystocia assisted delivery and uncoordinated attempts to stand postpartum
187
where does the gastrocnemius typically tears?
**origin** at the** caudal and dista**l aspect of **femur**
188
describe clinical signs of partial rupture of gastrocnemius
In partial ruptures, the animal is acutely lame and shows a partially dropped tarsus or a gait abnormality characterized by lateral rotation of the calcaneus and medial rotation of the toe.44
189
describe clinical signs of total rupture of gastrocnemius
In total ruptures involving gastrocnemius and superficial digital flexor muscles, the reciprocal apparatus is dysfunctional and the animal cannot bear weight on the affected limb.
190
diagnosis
Figure 85-10. Three-week-old Quarter Horse foal with an avulsion of the gastrocnemius muscle.
(A) Weight-bearing results in marked flexion of the tarsus and hyperextension of the stifle. (B) Application of a tube cast over the tarsus allows the foal to bear weight.
191
How do you diagnose rupture of gastrocnemius
US and radiographic exam of the stifle should be done to rule out avulsion fractures from the supracondylar region of the femur
192
61% of the foals had concurrent disease beside gastrocnemius rupture. Name them
enterocolitis,
flexural limb deformities,
encephalopathy,
pneumonia,
rib fractures,
sepsis,
spinal cord trauma,
superficial digital flexor tendon rupture
193
what is the treatment of rupture gastrocnemius?
Management involves stall rest alone or in combination with stabilization of the affected limb in the presence of significant disruption of the reciprocal apparatus.
Stabilization can be achieved using custom-made splints or sleeve casts applied to the dorsal or plantar aspect of the tarsus, keeping it in a normal weight-bearing position.45,47 A tube cast over the tarsal region can also be used (see Figure 85-10, B). region should not be incorporated into the splint or cast to avoid tendon laxity. The splint or cast should be changed at regular intervals and be left in place for 4 to 5 weeks, followed by a Robert Jones bandage for an additional 2 to 4 weeks.
194
what is the prognosis for foals and for adults for gastrocnemius rupture
Adults complete = poor
Adults partial = favorable
Foals = favorable for partial + complete
195
What are the types of fracture in distal tibia?
Adults
***Lateral and medial malleoli**
***DIRT**
Larger incl. more tibia Other articular tibial #
*Foals
- Salter Harris
-->**Types III, IV **Combinations
196
Figure 99-10. Lateromedial radiograph showing a large fracture fragment including the distal intermediate ridge of the tibia (A). This fracture was fixed with two cortical lag screws across the fracture
plain (B).
197
what to do?
Figure 35.1 (A) Craniocaudal and (B) lateromedial radiographs
depicting highly comminuted diaphyseal fracture of the tibia in an adult horse. Attempts at repair are futile.
198
Figure 35.2 (A) Craniocaudal and (B) lateromedial radiographs
depicting simple spiral diaphyseal fracture of the tibia in a foal.
Double plate repair can be successful in most foals.
199
What is the most common tibial fracture in foals?
Proximal tibial physis - type II salter harris
Methods of fixation include the use of transverse pins
in the configuration of a Charnley apparatus, cross‐pin
fixation, lag screw fixation, and use of medial bone
plates.
200
Figure 35.11 Repair of type II fracture of the proximal tibial physis
shown in Figure 35.3, using two narrow 4.5 mm dynamic compression
plates. Craniocaudal radiographs (A) immediately postoperatively and
(B) four months postoperatively showing healed fracture
201
Tibial tuberosity fractures how to repair?
Conservative crosstying to prevent recumbency or if displaced (figure) open reduction and internal fixation. Figure 35.14 Large distracted intraarticular tibial crest fracture in a nine‐year‐old Thoroughbred. (A) Preoperative lateromedial radiograph
showing effects of tension from the patellar ligament insertions on the fractured tibial crest. (B, C) Repair of the fracture using three
6.5 mm partially threaded lag screws, and supplemented with two broad 4.5 mm locking compression plates attached with a combination
of cortical screws and locked screws.
202
Figure 35.12 The 4.5 mm locking compression T‐plate suitable for
repair of proximal tibial physeal fractures in foals.
203
Figure 35.15 Smaller nonarticular tibial crest fracture in a 13‐year‐old Warmblood repaired using tension band screws and wire.
(A) preoperative lateromedial radiographs showing the tibial crest fracture (arrows). (B, C) Lateromedial and craniocaudal radiographs
seven days after repair using 5.5 and 4.5 mm screws, washers, and tension band wires. Note that the screws have already deformed,
indicating marginal stability. Healing was uneventful.
204
Diaphyseal tibial fractures describe them
are high energy, catastrophic injuries caractherized y extensive comminution abd ioe(fall or kick)
In foals is rare to be comminuted it is usually oblique or spiral configuration
205
can repair of diaphyseal tibial fractures be performed?
Not in adults, only in small breeds of horse such as ponies and miniature horses
206
Incomplete tibial fractures how do you manage?
it is always a dilemma because this fractures can progress to complete catastrophic disruption of the bone and overlying soft tissues
Most are managed conservatively i(cross tied or sling) f the incidence of fracture is less than 50%
207
how do you manage stress fracture?
Four to six months of rest are recommended,
with a return to training being contingent on
follow‐up evaluation revealing radiographic healing and
inactivity of the periosteal response. If available, scintigraphic
examination with 99mTc‐MDP is performed to
determine whether the bony response is quiescent.
208
prognosis for diaphyseal fracture repair in foals
good prognosis for survival and reasonable for athletic soundness
209
prongosis for all types of tibial fracture
salter harris type II=good
tibial tuberosity=good
diaphyseal= good
incomplete tivial = good
tibial stress = excellent
210
describe surgery according to Lambert 2018
MIPO or open approach
LR with affected limb down for unila arthod
**Needle** inserted in the **medial aspect of PIT, DIT and TMT** confirmed via fluoro
**3.2 mm drill** bit in **fanning tx removed articular cartilage of DIT and TMT **and drill holes packed with **synthetic bone putty**
MIPO using LCP plate at the level of central tarsal **bone make incision 5 cm distal** to **TMT **and place subcut the plate in distal-to-proximal direction
Screw through stab incisions
**LCPT, a 5-hole, 4.5mm plate** was used and once plate positioning confimed via fluoroscopy, plate was contoured using plate benders and with **push-pull device** the plate was affixed to the MTIII through the second most distal combi-hole in longitudinal axis of the plate
**3.2 mm thread hole drilled** in the **central tarsal bone** in the central hole of the transverse axis of the plate
**Measurement** with **depth gauge**
Hand tap using **4.5mm tap** and i**nsertion of 4.5 mm cortical screw** of appropriate length
**Cortical screw in LOAD position **in the **third hole from the top**
**Locking drill guid** affixed to the** threaded portion of the stacked hole** at the **dorsal aspect of transverse segment** of the plate
**4.3mm drill bit** used to drill through **central tarsal bone**.
The hole was **measured** using depth gauge and a** 5.0mm LHS inserted**
The remainder of the plate holes were secured with LHS
211
The distal shaft of the LCP T‐plate
is manufactured in 4‐, 6‐, 8‐, and 10‐hole lengths, providing
different sizes to accommodate varying configurations
of the proximal fracture and increased‐sized
foals
