Chapter 92 - part 3 sesamoid fx and manica flexoria Flashcards
1
Q
What are the different types of sesamoid bone fracture?
A
2
Q
A
I Apex fractures
II Midbody fractures
III Base fractures
IV Abaxial fractures
V Axial fractures
VI Comminuted fractures
3
Q
A
Bones and joints: 1- Third metacarpal bone, 1a- body, 1b- distal metaphysis, 1c- condyle;
2- Fourth metacarpal bone (end); 3- Proximal phalanx, 3a- palmar eminence; 4- Lateral collateral ligament of the metacarpophalangeal joint, 4a- superficial layer, 4b- deep layer; 5- Collateral
sesamoidean ligament of the metacarpophalangeal joint; 6- Palmar (intersesamoidean) ligament,
6a- suprasesamoidean part, 6b- sesamoidean part, 6c - metacarpointersesamoidean ligament;
7- Lateral oblique sesamoidean ligament; 8- Proximopalmar recess of the metacarpophalangeal
joint; Tendons: 9- Dorsal digital extensor tendon; 10- Lateral digital extensor tendon (cut longitudinally),
10a- distal enthesis; 11- Third interosseous muscle (suspensory ligament), 11a- lateral
branch, 11b- lateral extensor branch (cut).
4
Q
A
Bones and joints: 1- Third metacarpal condyle (sagittal ridge); 2- Proximal phalanx (medial palmar
eminence); 3-Medial proximal sesamoid bone, 3a- apex, 3b- base; 4- Lateral proximal sesamoid
bone, 4a- interosseous surface, 4b- articular surface; 5- Medial palmar process of the distal
phalanx; 6- Lateral palmar process of the distal phalanx; 7- Metacarposesamoidean joint space;
8- Palmar (intersesamoidean) ligament (suprasesamoidean part); 9- Cruciate sesamoidean ligaments;
10- Straight sesamoidean ligament; 11- Lateral short sesamoidean ligament; 12- Medial
oblique sesamoidean ligament; 13- Lateral oblique sesamoidean ligament; 14- Proximopalmar
recess of the metacarpophalangeal joint; 15- Lateral collateropalmar recess of the MPJ;
Tendons and associated structures: 16- Third interosseous muscle (suspensory ligament),
16a- medial branch, 16b- medial extensor branch, 16c- lateral branch, 16d- lateral extensor
branch; 17- Deep digital flexor tendon, 17a- medial lobe, 17b- lateral lobe; 18- Superficial digital
flexor tendon, 18a- medial branch, 18b- lateral branch; 19- Proximal digital annular ligament,
19a- medial proximal attachment, 19b- lateral proximal attachment; 20- Distal digital annular
ligament; 21- Digital sheath cavity, 21a- transverse synovial plica;
5
Q
What type of bone is the proximal sesamoid bone (PSB) and how does it affect its function?
A
Dense cancellous bone; it is prone to fractures due to tension.
6
Q
What is a significant challenge in the healing of proximal sesamoid bone fractures?
A
The continual tension and poor blood supply.
7
Q
How do vascular channels within the PSB relate to fracture risk?
A
They act as “stress risers,” potentially predisposing the bone to fractures.
8
Q
What factor contributes to the failure of the PSB under maximal joint extension?
A
Bending and compressive forces experienced during maximal joint extension.
9
Q
What are some predisposing factors to PSB fractures mentioned in the text?
A
Musculotendinous fatigue, poor conformation, shoeing practices, and poor conditioning.
10
Q
In which breed of horses are apical fractures especially common?
A
Standardbreds
++ HL
Lateral
in THO is FL
11
Q
What often dictates the prognosis for horses with apical fractures?
A
The extent of loss of suspensory ligament insertion and preexisting desmitis
12
Q
What is the recommended treatment for apical fragments up to one-third of the proximal sesamoid bone?
A
Removal of apical fragmentsby arthroscopy
13
Q
describe surgical approach to apical fx of sesamoid
A
DR or LR with esmarch
In lateral recumbency the arthroscope is inserted through the proximal most aspect of the palmar pouch, whereas the instruments are inserted through a separate incision at the level of the fracture plane. Fracture line easy to see.
Dorsal recumbency allows the insertion of the arthroscope from the contralateral palmar pouch to facilitate better visualization
14
Q
How does the size of an apical fracture impact the approach to treatment?
A
Larger apical fractures may require internal fixation in proximal-distal oriented lag screw as mid-body fractures if is one third
15
Q
What is one advantage of arthroscopic removal of apical fractures?
A
It results in less-extensive dissection and secondary fibrosis
16
Q
Recovery the horse with normal bandage in apical fractures?
A
No, splint bandage in recovery
17
Q
Apical-abaxial fractures are often..
A
comminuted
18
Q
Proximal sesamoid bones in the forelimb are
A
larger and more elongated than in the hindlimb
19
Q
The proximal scutum is part of the suspensory apparatus, intercalated between the elastic _____________ ____________ proximally and the inelastic distal _________________ ____________distally
A
the elastic suspensory ligament
proximally and the inelastic distal sesamoidean ligaments
distally
20
Q
The distal sesamoidean ligaments are the functional
continuation of the
A
suspensory ligament to the proximal
and middle phalanges
21
Q
Name the distal sesamoidean ligaments from dorsal to palmar/plantar (and in corresponding ascending length),
A
medial and lateral short,
cruciate,
oblique, and the
unpaired straight distal sesamoidean ligaments.
The distal sesamoidean ligaments originate from the base of the proximal sesamoid bones and the ISL.
22
Q
cancellous bone is weakest in (tension or compression?)
A
tension
23
Q
proximal sesamoid bones are not fully mineralized until
A
3 months of age
24
Q
Apical fractures are articular?
A
yes they are almost always articular
25
Most apical fx can be ID in standard LM, DP, DLMP and DMLP oblique but was is the best view for apical?
20° proximal‐distal obliquity of standard lateromedial
and oblique projections
25
Dx and tx
Figure 21.5 Acute apical fracture of the medial proximal sesamoid bone, with multiple small proximally displaced comminuted
fragments. (A) Preoperative lateromedial radiograph. (B) Arthroscopic removal of the principal apical fragment of bone
26
The apical fragment is removed withwhat instrument?
Sharp dissection of the fragment is performed
with straight and curved arthroscopy knives and curved elevator and SL sectioned with arthroscopic scissors or electrocautery probe (to diminish bleeding)
26
tx
Figure 21.7 Repair of a large apical fracture of a medial proximal sesamoid bone. (A) Lateromedial and (B) dorsomedial‐palmarolateral
oblique (DMPLO) radiographic projections at presentation. (C) Lateromedial projection 10 weeks postsurgery;
note the screw trajectory.
27
ALL fracture sesamoidean fractures except _______ nonarticular fractures result in MCP/MTP effusion with moderate to severe lameness
abaxial
28
Prognosis for apical sesamoid fractures
64% surgically tx horses raced afterward
29
Apical-abaxial are mostly on the FL or HL?
FL
29
What is the radiograph indicated to see this type of fractures **apical abaxial?**
**Proximal 60º lateral-distomedial oblique, **proximal 60º medial-distolateral oblique along with standard views
30
What is the important complementary exam to perform?
US of SL
30
Acute, comminuted, and displaced apical‐abaxial fracture of a medial sesamoid bone suitable only for fragment removal.(A) Lateromedial, (B) dorsopalmar, (C) dorsolateral‐palmaromedial oblique (DLPMO), and (D) proximolateral‐distomedial obliquepreoperative radiographic projections defining the comminuted nature of the fracture. (E) Longitudinal ultrasound image demonstratingsignificant compromise to all but the most abaxial portion of the suspensory ligament branch and loss of ligament tension followingfracture displacement. (F, G) Contralateral arthroscopic views, at evaluation and following fragment removal and debridement of thesesamoid bone and disrupted suspensory ligament.
31
Dx and projection
Figure 92-21. Elevated 60-degree lateromedial radiographic projection (L60°Pr-DiMO) of the proximal sesamoid bones to evaluate the intraarticular component of an abaxial sesamoid fracture (arrow). This fragment enters the joint
31
What surgical technique is required for adequate union of **midbody proximal sesamoid fractures**?
Internal fixation, screws (single 4.5 or two 3.5mm)
32
Which screws are used for proximal to distal oriented screw insertion at the apex of the bone in **midbody prox sesa fx?**
A single 4.5-mm cortex screw or two 3.5-mm screws
32
From where is screw fixation in lag fashion performed for oblique fractures OF **MIBDOY fractures**?
From the base or the apex, depending on the fracture plane
33
Where should the screw head of the cortex screw be positioned when inserting from the base in the case of **midbody or basal fractures?**
Between the** oblique **and **straight distal sesamoidean ligaments** in a natural fossa at the base of the sesamoid bone
33
What is essential for maintaining interfragmentary compression during screw insertion?
Use of large pointed reduction forceps
33
****What percentage of Thoroughbred horses return to active racing after interfragmentary screw fixation in lag fashion of **midbody fx?**
Up to 60%
33
**Abaxial fractures** have 2 locations name them
Enter the joint (artho tx)
Located palmar/plantarly and is EXTRAARTICULAR (conservative tx)
34
Figure 21.10 Nonarticular abaxial fracture of a medial sesamoid bone in the forelimb. Surgery is unnecessary. Radiographs including the(A) dorsopalmar, (B) dorsomedial‐palmarolateral oblique (DMPLO), and (C) proximolateral‐distomedial skyline projections define thepalmar abaxial location (arrows), without joint involvement
34
In which breed of horses are midbody and basal fractures more prevalent?
Thoroughbreds
35
For which breed of horses has circumferential wiring largely been reserved?
Standardbreds
35
Figure 21.11 Large articular abaxial fracture of a forelimb medial sesamoid bone, suitable for arthroscopic removal. Radiographs define
the fracture, including (A) dorsopalmar, (B) dorsolateral‐palmaromedial oblique (DLPMO), and (C) proximolateral‐distomedial skyline
projections. Note the dorsal intraarticular position on the skyline. Arthroscopic images obtained from a contralateral palmarolateral portal
show (D) probe evaluation of the fragment displaced from the abaxial margin of the medial sesamoid bone; (E) dissection from the
suspensory ligament insertion with a fixed blade knife; (F) removal of disrupted ligament with a synovial resector; and (G) inspection of
the debrided fracture site.
36
Abaxial fractures require verification of which structure?
A. SDFT
B. SL
C. DDFT
D. Distal sesamoid ligaments
B. SL
37
Where is the most common site for abaxial fracture?
FL medial sesamoid bone
37
What is the prognosis of **abaxial fractures?**
Depends on teh SLB insertion damag, but article 1998 JAVMA 83% return racing post arthro removal
37
Are abaxial articular or non-articular fractures?
Both types are possible
38
How do you treat **non-articular abaxial fx?**
Conservatively and will heal via fibrous union in 3-6 m rest
38
**Articular abaxial sesamoid** are removed by arthroscopy. What is the preferred position?
DR preferrred contralateral scope and ipsilateeral instruments
38
If a large abaxial fragment is present what should be done?
LAg screw fixation with 3.5/2.7 mm length cortical screws stab incision in SL insertion arthro guided
39
How do you perform the recovery anesthesia from abaxial fracture?
Cast
39
Why the poor healing of uniaxial mid-body fractures?
fragment separation distracting forces of suspensory apparatus
39
**Uniaxial mid-body** fractures have a:
A. good healing
B. poor healing
B. poor healing
39
What is the treatment of choice for **uniaxial mid-body fractures?**
D. lag screw fixation ideally two 4.5 or 3.5mm arthroscopically guided use forceps
40
What are the ligaments who are in this region?
Short DSL, cruciate DSL, straight DSL, oblique DSL and annular ligament
40
What other technique could be used beside the placement of screws** uniaxial mid-body fractures**?
Wire technique
40
Figure 21.15 Acute basilar fracture of a forelimb medial proximal sesamoid bone with sagittal comminution of the distal fragmentstreated with hemicerclage wire. Radiographs useful in identifying the comminuted fragments include (A) dorsopalmar, (B) lateromedial,(C) dorsomedial‐palmarolateral oblique (DMPLO), and (D) dorsoproximomedial‐palmarodistolateral oblique projections. Althoughmeasuring just less than 25% of the proximodistal length of the bone, fractures of this size compromise the suspensory apparatus to thesame degree as mid‐body fractures. (E) Intraoperative dorsopalmar radiograph showing ipsilateral arthroscope position and hemicerclagewire in position; a marker needle has been inserted in the transverse fracture plane. (F) Dorsopalmar radiograph with hemicerclage wire atthe completion of surgery. (G) Dorsopalmar and (H) lateromedial radiographs with the limb immobilized in a cast 10 days post‐surgery.(I) Dorsopalmar and (J) lateromedial radiographs eight weeks post‐surgery; note the periarticular swelling (arrow), which is common withsesamoid wiring. (K, L) Radiographs 12 weeks post‐surgery, showing progressive healing.
41
Figure 21.13 An acute, transverse, mid‐body fracture of a forelimb medial sesamoid bone repaired with a single 4.5 mm cortical screw.Radiographs show the transverse distracted fracture, including (A) lateromedial, (B) dorsomedial‐palmarolateral oblique (DMPLO), and(C) dorsopalmar projections. Measurements of the proximodistal lengths of the basilar fragment and the contralateral sesamoid bone arecalculated on the dorsopalmar view. (D–G) Determination of drill site and trajectory for distal to proximal repair using needle placementand subsequent lateral and dorsopalmar radiographs.
41
Figure 21.13 An acute, transverse, mid‐body fracture of a forelimb medial sesamoid bone repaired with a single 4.5 mm cortical screw.Radiographs show the transverse distracted fracture, including (H) “Surgeon’s‐eye” view of drill trajectory and (I) arthroscopically guided reduction.(J, K) Radiographic evaluation of the glide and thread holes, respectively
41
Interfragmentary screw fixation in lag fashion returns up to % of Thoroughbred horses to active racing for **mid body fx**
60% whereas circumferential wiring has largely been reserved for Standardbreds
42
what is the prognosis for horses with **basal slab fractures** involving the origin of all distal sesamoidean ligaments?
Unfavorable, because it is the orgin of** ALL distal sesamoidean ligaments**
thin fragment is a challenge to insert a screw
43
What is the preferred method of lag screw fixation for thin basal slab fractures?
Two 3.5-mm cortex screws
43
What is the return to racing rate for horses with basal osteochondral fragments that do not extend to the palmar/plantar surface?
Approximately 59%
43
In basal sesamoidean fractures there is an inverse relation between the dorsopalmar/dorsoplantar fragment lenght and
the likehood to return to race
44
Can you remove the basal sesamoidean fragment by arthroscopy?
yes you can when there is synovial tissue obscuring the fragment
LR or DR and esmarch
Ipsilateral scope and instrument portals vs ipsi/contralateral if dorsal instrument portal just distal to collateral sesamoidean ligament trajectory alongside parallel to base of PSB
44
How common are sagittal fractures in sesamoid bones?
Rare
45
With which other injury do sagittal fractures typically occur?
Condylar fractures
45
Figure 21.18 Axial sagittal fracture of the (A) (B)
lateral proximal sesamoid bone (arrow
heads) associated with a long displaced
fracture of the lateral condyle of a third
metatarsal bone. (A) Dorsoplantar
radiographic projection; (B) arthroscopic
visualization of the fracture (small arrows)
via an ipsilateral arthroscopic portal. Note
the radiologically undetected distal
comminution (large arrow) with minimal
disruption of the articular cartilage
proximally. ISL, intersesamoidean
ligament; LS, lateral sesamoid.
46
What is a possible repair method for isolated sagittal fractures?
Lag screw fixation, 3.5-mm cortex screws with radiographic monitoring in lateral to medial orientation
ESSENTIAL to have radio control to prevent GLIDE HOLE extending into narrow fracture fragment
46
Why is important to have radiographic control in the sagital sesamoidean fractures repair?
screw placed in lateral to medial orientation
ESSENTIAL to have radio control to prevent GLIDE HOLE extending into narrow fracture fragment
46
After how many weeks is the cast typically exchanged for a bandage in sagittal fractures?
2 to 3 weeks
46
What is the likely outcome for horses with sagittal fractures occurring with displaced lateral condylar fractures?
Unlikely return to racing
47
In what situation might MCP/MTP arthrodesis be necessary?
When there is injury to the intersesamoidean ligaments
47
What is the typical prognosis for horses with sagittal fractures and associated injuries?
Retirement from racing is inevitable
48
Labbe et al 2022 EVE Radiographic technique to improve diagnosis of sagittal axial sesamoid fracture in racing Thoroughbreds with lateral condylar fracture - What is the most sensitive radiographic view to identify sagittal axial fractures of the lateral proximal sesamoid bone?
A) Flexed lateral view
B) Standard mediolateral view
C) 20-degree dorsomedial-palmarolateral oblique (DMPLO) viewD) Palmarodorsal view
C) 20-degree dorsomedial-palmarolateral oblique (DMPLO) viewD) Palmarodorsal view
48
Why is the identification of axial sesamoid fracture critical in cases of lateral condylar fractures?
It provides the most accurate prognosis for return to racing.
49
Figure 21.19 Fetlock breakdown injurywith comminuted, displaced, biaxialfractures of the forelimb proximal sesamoidbones in a three‐year‐old Thoroughbred.(A) Lateromedial and (B) dorsopalmarprojections show the numerous largefragments of the shattered sesamoids, andsmall comminuted fragments scatteredthroughout the region indicative of thegross soft tissue disruption that isassociated with such injuries. Although theanimal was unwilling to load the leg, notethe hyperextended metacarpophalangealjoint produced by limb weight only.
50
Fetlock breakdown injury with comminuted, displaced, biaxial fractures of the forelimb proximal sesamoid bones - arthrodesis of the fetlock is required for salvage
51
Biaxial fratures of the mid-body what is the treatment?
Salvage MCP/MTP arthrodesis - laceration of neurovascular bundle is the key for prognosis high risk of ischemia
52
Proximal sesamoid fractures in foals are common in up 2 months, what is the treatment?
Restricted exercise weak firm ground
53
What has been observed in the proximal sesamoid bones associated with injury or avulsion of the intersesamoidean ligaments?
Axial lysis with occasional fragmentation
53
Figure 92-22. (A) Lateromedial radiographic projection of the MCP region depicting bilateral transverse midbody fractures of the proximal sesamoid bones resulting in a breakdown of the suspensory apparatus. (B) Repair was achieved through an MCP arthrodesis using a dynamic compression plate (DCP) applied to the dorsal surface of the limb and a tension band wire for palmar support.
53
Figure 92-23. Axial osteitis of the proximal sesamoid bone. (A) Radiographs show lysis along the axial perimeter of the medial sesamoid bone. (B) T1-weighted MRI better defines the bone lesion and intersesamoidean ligament involvement.
53
53
In which breed of horses is axial osteitis of the proximal sesamoid bones most frequent?
Warmbloods, especially Friesians
54
What was the initial belief about the origin of axial osteitis in the proximal sesamoid bones?
Septic origin
55
Which limb is predominantly affected by axial osteitis of the proximal sesamoid bones?
Hindlimb
55
What treatment has shown better results for axial osteitis of the proximal sesamoid bones?
Arthroscopic surgical débridement and stem cell grafting
55
Figure 92-25. (A) Lateromedial radiographic view showing dorsal sagittal ridge OCD (arrow) that involved the adjacent condyle. (B) Arthroscopic examination shows the sagittal ridge (SR) distal to the fragment (arrows), the metacarpal condyle (MC), and villonodular pad (VP).
55
What is often the cause of soft-tissue masses in the dorsal aspect of the MCP joint?
Chronic fibrosing synovitis, secondary to proximodorsal fragments that are nt immediately removed
56
Which condition is most frequently associated with the development of chronic proliferative masses?
Proximodorsal osteochondral fractures untreated by fragment removal
56
what type of horses are predisposed to chronic proliferative synovitis?
Horses with long pasterns
56
What radiographic sign might indicate chronic proliferative synovitis?
What radiographic sign might indicate chronic proliferative synovitis?
56
What radiographic sign might indicate chronic proliferative synovitis?
What radiographic sign might indicate chronic proliferative synovitis?
56
What radiographic sign might indicate chronic proliferative synovitis?
What radiographic sign might indicate chronic proliferative synovitis?
57
Most chronic proliferative synovitis are what size in mm?
7 to 10 mm in diameter
57
What radiographic sign might indicate chronic proliferative synovitis?
What radiographic sign might indicate chronic proliferative synovitis?
58
What radiographic sign might indicate chronic proliferative synovitis?
What radiographic sign might indicate chronic proliferative synovitis?
59
What radiographic sign might indicate chronic proliferative synovitis?
What radiographic sign might indicate chronic proliferative synovitis?
59
describe what is the cause of this 8mm mass in the MCP joint
Figure 92-24. Arthroscopic removal of an 8-mm chronic proliferative (villonodular) mass from the MCP joint using a biopsy punch rongeur.
60
what is the prognosis of horses after arthroscopy and removal of vilonodular synovitis in horses?
It s very painful but the horses respond very well
61
what happened?
Figure 92-28. Luxation of the metacarpophalangeal joint. (A) Standing dorsopalmar radiographic projection shows normal MCP alignment. (B) Bending stress luxates the joint, confirming complete medial collateral ligament rupture.
61
What is a common cause of lateral or medial complete luxation of the MCP and MTP joints in horses?
Entrapment of the distal limb in ground holes or cattle grates.
61
What is the initial treatment for closed luxations of the MCP/MTP joints?
Cast fixation for 6 weeks.
62
What composes each collateral ligament of the MCP/MTP joint?
A superficial part (long) that originates in the epicondylar fossa of MCIII/MTIII and a deep (short) part that courses distopalmarly/-plantarly.
63
Is imbrication or repair of the collateral ligament usually necessary in closed luxations?
No, it is not usually necessary.
64
How are open luxations of the MCP/MTP joints treated?
With wound débridement, soft-tissue closure, and extensive antibiotic lavage.
65
What long-term complications did the most recent case series identify in horses treated conservatively for MCP luxation?
Osteoarthritis in the affected fetlock joint and occasionally in the PIP.
66
What percentage of horses returned to use as pleasure riding horses after conservative treatment for MCP luxation?
67% returned to use as pleasure riding horses
67
What is the prognosis after the development of infection in the MCP joint following luxation?
The prognosis is guarded, with chronic lameness often expected.
68
OCD and SCB lesions are common at what age?
12 to 24 months olda
69
OCD dorsal is from sagittal ridge and parasagittal condylar but what about the palmar?
Palmar MCIII and plantar MTIII lesions are relatively inaccessible, and surgical therapy is not possible unless the lesion is located unusually far caudad on the condyles or sagittal ridge.
70
Saggital ridge fragments are removed with classica arthroscopic portal on the proximolateral quadrante under DR, but what if it is more distally on the SR?
For lesions located more distally on the sagittal ridge of MCIII/MTIII, this technique is modified by positioning the arthroscope portal just distal to the center of the outpouching
71
Narrow cysts and wider channels cysts tx
Narrow cysts can be tx with injection of HA but it may take 1 to 2 years to heal
wider channels require debridement with arthroscopy or transcortical cyst
71
Dorsal and Palmar cysts are also approachable with arthroscopy?
Surgical débridement of the cysts can be accomplished via dorsal arthroscopy with the MCP joint flexed
HOWEVER proximal phalanx can be débrided with difficulty from the articular surface, particularly in MTP joints where the joint separates with flexion and palmar cysts are rare and best approached transosseously through drilling, or for application of a transcystic cortical screw
72
Figure 92-26. Dorsopalmar radiographic views of the MCP joint. (A) Subchondral cystic lesion with small communication into the joint generally respond well to conservative therapy, such as intraarticular hyaluronan or intralesional corticosteroid injections. (B) SCLs with wide canals (arrows) often need surgical débridement.
72
dx and tx
Figure 92-27. Subchondral cystic lesion originating from the sagittal groove in the proximal phalanx.
(A) T2-weighted frontal plane MRI and (B) STIR images, show the cyst distal to the sagittal groove and the proximal phalanx. (C) Dorsoplantar radiographic projection 7 days after insertion of a 4.5-mm cortical screw across the sagittal groove cyst, and a 3.5-mm screw inserted further dorsal to treat a second cyst.
73
distal physis of the MCIII or MTIII develop relatively often in foals; most are______ deformities
distal physis of the MCIII or MTIII develop relatively often in foals; most are varus deformities
74
concurrent to a varus deformity in the MCIII and MTIII the foal develops a
concurrent valgus of the carpus or tarsus
75
flexural deformities if bilateral, the foal can have difficulty in
rising and tends to knuckle over at MCP joint
76
what are the causes of flexural deformities in foals?
tension is apparent in both the DDFT and SDFT; in others, the common digital extensor tendon is ruptured.
77
what is teh cause of an acquired flexural deformitie?
The pathogenesis of the acquired form of flexural deformity is thought to involve pain-induced reflex loops in the ipsilateral limb, often precipitated by other skeletal disease
78
How does untreated tenosynovitis lead to complex tenosynovitis?
By resulting in DFTS fibrosis, repeat tearing, and annular ligament thickening.
79
What are the common symptoms of annular ligament constriction in animals?
Chronic lameness, exacerbated by fetlock flexion, DFTS effusion, and thickening.
79
How can ultrasound be useful in evaluating tendon lesions and synovial tendon sheath thickness?
It helps in measuring the thickness of the synovial tendon sheath.
80
What is the preferred method for treating tenosynovial masses in animals?
Endoscopic examination (tenoscopy).
81
Where is the entry portal for routine tenoscopy of the DFTS?
Palmarolateral or plantarolateral surface distal to the palmar/plantar annular ligament.
82
How is hemorrhage controlled during extensive synovial resection?
By applying a tourniquet proximal to the DFTS.
83
What are the advantages of tenoscopic annular ligament release compared to traditional surgical methods?
It allows better wound healing and earlier postoperative exercise.
84
What can be injected into the tendon sheath during postoperative management, and when is it typically administered?
Hyaluronan (20–40 mg) can be injected into the tendon sheath at the time of wound closure or later at suture removal.
85
Describe in detail the annular ligament transection after the portals are made
The slotted cannula with obturator in place is inserted under direct arthroscopic visualization. The insertion path must be external to the manica flexoria, or this ring of the SDF will be divided along with the annular ligament. As the obturator nears the distal portal, the arthroscope is removed, and the obturator and cannula are exteriorized through the vacant portal. The unsheathed arthroscope is inserted to view and verify the flexor tendons, sesamoid surface, and annular ligament. The slot is oriented to open directly toward the annular ligament, and the 90-degree angle sharp blade is drawn across the fibers of the annular ligament to sever the full thickness of this structure.
86
The insertion path of the slotted cannula must be oriented toward what and must be external to what?
The insertion path must be external to the manica flexoria and the slot is oriented to open directly toward the annular ligament, and the 90-degree angle sharp blade is drawn across the fibers of the annular ligament to sever the full thickness of this structure.
87
How can tissue plasminogen activator (tPA) be used postoperatively to reduce fibrin deposition and adhesion reformation?
Sequential injection of tPA for 3 days after surgery, using 500 μg injected daily, may reduce fibrin deposition and adhesion reformation.
88
How long is the limb usually bandaged after surgery for tendon-related conditions?
The limb is usually bandaged for 3 to 4 weeks after surgery.
89
When should hand walking be initiated post-surgery, and why is it particularly helpful?
Hand walking should be instituted after 5 days, and it is particularly helpful if tendon adhesions were present at surgery.
90
Noguera 2020 In a case series of 130 horses that had tenoscopic surgery for nonseptic tenosynovitis of the DFTS associated with longitudinal tendon tears, what % of horses returned to an equal or higher level of work after surgery?
Only 38% of these horses returned to an equal or higher level of work after surgery.
91
Examples of contrast radiographs demonstrating diagnostic criteria usedfor assessment: a) the two parallel lines which delineate the manica flexoria (MF)just proximal to the proximal sesamoid bones (PSB), at the dorsal border of thedeep digital flexor tendon (DDFT), are not visible (arrow). The most dorsal line isnot evident; b) the most dorsal of the parallel lines does not extend distally tothe proximal border of the PSB (arrow), it tapers further proximal in the digitalflexor tendon sheath (DFTS) than at the level of the PSB; c) isolated area ofcontrast overlying the dorsal border of the DDFT at the level of the MF (arrow);d) thin line of contrast extending proximally and obliquely from the outpouchingof the DFTS distal to the PSB, within the outline of the DDFT (arrow); e) unequaldistribution of contrast in the DFTS, proximal and distal to the PSB (arrow); f)Irregular soft tissue contour of the palmar/plantar aspect of the limb at the levelof the PSB (arrow).
92
FIGURE 8 Tenoscopic visualisation of the digital flexor tendon
sheath of a typical lesion seen at the plantar aspect of the superficial
digital flexor tendon (SDFT) in a case with a concurrent plantar
annular ligament (PAL) constriction; the tenoscope is inserted at the
level of the base of the lateral proximal sesamoid bone and directed
to proximal. The PAL has been transected using a hook knife. Left in
the image the plantar surface of the SDFT can be seen; note the
marked superficial fibrillation and hyperemic surface of the tendon in
the area in contact with the PAL
92
FIGURE 1 (A) Tenoscopic view of the digital flexor tendon sheath (DFTS); the tenoscope is inserted at the level of the base of the lateral
proximal sesamoid bone and directed to the proximal pouch of the tendon sheath. View of a minor fibrillation seen at the distal margin of the
manica flexoria (MF); this lesion was classified as mild. (B) Tenoscopic view of a case with complete rupture of the MF, categorised as severe.
Note the complete separation of the MF (arrow) from its medial attachment. DDFT, deep digital flexor tendon. (C) Contrast tenogram of the
DFTS corresponding with the case shown above with a rupture of the MF. Note the manica flexoria is not present (only one line, instead of two,
at the level of the MF proximal to the proximal sesamoid bones) (arrow)
93
FIGURE 4 Contrast radiography of the digital flexor tendon
sheath of a horse with a longitudinal tear at the deep digital flexor
tendon (DDFT). See the linear contrast accumulation within the
outline of the DDFT (arrows)
94
FIGURE 9 (A) Ultrasonographic image
of a longitudinal lesion at the lateral
border of the deep digital flexor tendon
(DDFT) at the level of the manica flexoria
(MF). Note the irregular appearance of the
lateral DDFT margin with an area of
decreased echogenicity (arrow).
(B) Tenoscopic view of the same DDFT
lesion. The tenoscope is inserted at the
level of the base of the lateral proximal
sesamoid bone and directed to proximal.
Note the significant tendon fibrillation
along the lateral edge of the tendon, the
case was classified as severe
95
Figure 1. Transverse ultrasound image (lateral is to the left) of the proximal portion of the DFTS distended by anechoic fluid. There is a lesion at the lateral border of the DDFT, evident as a slightly irregular outline of the tendon surface (arrow) with a hypoechoic area within the lateral aspect of the DDFT. Also note the thickening of the subcutaneous tissues (vertical white line) and the wall of the digital flexor tendon sheath. DFTS= digital flexor tendon sheath; DDFT= deep digital flexor tendon; SDFT= superficial flexor tendon.
96
Figure 2. Transverse ultrasound image, proximal to the fetlock at the level of the MF. Complete rupture of the MF with a complete lateral dislocation (arrow). Note the distention of the DFTS with anechoic fluid. DDFT= deep digital flexor tendon; SDFT= superficial digital flexor tendon; MF= manica flexori
97
Figure 3. Contrast radiography of the DFTS. A. Normal DFTS with intact MF, visible as two parallel lines (arrow).
The dorsal line is the MF and the palmar/plantar line is the dorsal limitation of the DDFT. B. Rupture of the MF. The
MF is not visible, i.e. there is no double line visible (arrow), only the line at the dorsal aspect DDFT is visible. DFTS =
digital flexor tendon sheath; MF = manica flexoria.
98
(C) Irregular
soft tissue contour at the plantar aspect
of the limb at the level of the proximal
sesamoid bones (red arrow), unequal
distribution of contrast in the DFTS
proximal and distal to the proximal
sesamoid bones (yellow asterisk) and at
the level of the fetlock canal (red
asterisk) consistent with moderate PAL
constriction. (D) Unequal distribution of
contrast in the DFTS proximal and distal
to the proximal sesamoid bones (yellow
asterisk) and at the level of the fetlock
canal (red asterisk), consistent with
marked PAL constriction.
98
FIGURE 2 Contrast tenograms of
the digital flexor tendon sheath (DFTS)
depicting various degrees of palmar/
plantar annular ligament (PAL)
constriction. (A) normal contrast
tenogram. (B) Irregular soft tissue
contour at the plantar aspect of the limb
at the level of the proximal sesamoid
bones consistent with mild PAL
constriction (red arrow).
99
Figure 1 Gross appearance of the manica flexoria with the associated
superficial and deep digital flexor tendons. a) The view from the dorsal
aspect of the manica flexoria showing the portion which apposes the
palmar/plantar wall of the digital flexor tendon sheath. b) Lateral view of the
manica flexoria with the probe inserted between the manica flexoria and the
deep digital flexor tendon, extending beyond the proximal areolar portion.
The opening through the areolar portion of the manica flexoria occurs at the
site of dissection from the dorsal digital flexor tendon sheath wall. c) Palmar
surface of the manica flexoria. The superficial digital flexor tendon has been
split to demonstrate the complete manica flexoria and its attachments.
MF = manica flexoria; SDFT = superficial digital flexor tendon; DDFT = deep
digital flexor tendon.
100
Within the proximal aspect of the digital
flexor tendon sheath, the manica flexoria
and the superficial digital flexor tendon
create a ring through which the _______________ passes.
Within the proximal aspect of the digital
flexor tendon sheath, the manica flexoria
and the superficial digital flexor tendon
create a ring through which the deep digital
flexor tendon passes.
101
What animals are more prone to manica flexoria tear?
Injury is more prevalent in the** hindlimbs, with cob and pony breeds**over-represented
Manica flexoria tears can occur at the medial or lateral attachment to the superficial digital flexor
tendon; however, the medial border appears
to be affected more commonly than
the lateral border
102
waht is the gold standard tx for dx of manica flexoria tear?
The gold standard technique for
diagnosis of manica flexoria tears is
tenoscopic examination, although ultra -
sonography and contrast radiography contribute
to the diagnosis in some cases
103
Douglas Wood guided palmar/plantar annular ligament (PAL) desmotomy to treat PAL constriction without concurrent intrathecal soft-tissue injury what was the surgical acess?
LR with limb uppermost and tourniquet applied in the proximal MC MTIII and the DFTS distended with sterile fluid
using a number
11 blade, was created into the distended pouch of the
DFTS on the lateral (upper limb) or medial (lower limb)
aspect of the limb between the PAL and proximal digital annular ligament. A cannula/obturator unit was introduced into the DFTS before the obturator was replaced with a 4 mm 30 degree forward oblique rigid endoscope.
In each case PAL constriction was confirmed to be present when there was difficulty maneuvering the cannula/obturator unit or the cannula/endoscope unit into or through the fetlock canal. Attempted passage of the endoscopic cannula/obturator unit or the cannula/rigid endoscope unit was repeated on several occasions and in several locations including dorsal to the DDFT, between the DDFT and the SDFT, and palmar/plantar to the SDFT prior to
making the diagnosis. An ipsilateral instrument portal
was created, with a number 11 scalpel blade, into the
proximal DFTS under tenoscopic guidance where
the rigid endoscope could pass through the fetlock canal and could be maneuvered to visualize the sheath wall, or blindly where visualization of the sheath wall could not be performed. If the rigid endoscope could be positioned in the fetlock canal but not advanced proximad, and the PAL could be visualized, an instrument portal was created through the PAL under tenoscopic visualization.
The PAL desmotomy was performed in each case under tenoscopic guidance with a hooked knife or number 12 blade on a number 7 handle transecting the ligament from its distal border proximad. In cases where the
instrument portal was created through the PAL, the distal segment was transected in similar fashion, before the hooked knife, number 12 blade, or a number 11 blade was directed proximad and used to transect the proximal segment of the PAL in sequential short incisions followed by advancement of the endoscope until the PAL was transected completely.
104
What is the normal value in mm for PAL thickness
and/or a skin-SDFT thickness
reported normal measurements of less than 2 mm
PAL and less than 5 mm skin-SDFT thickness
104
Douglas Wood VS 2024 What percentage of owners expressed satisfaction with the surgical outcomes?
Approximately 82% (50 out of 61 horses with follow-up).
There was an excellent prognosis for a return
to some form of exercise (90%), in horses without any lesions beside PAL
105
Douglas Wood VS 2024 What steps were included in the postoperative rehabilitation program?
Box rest for 4–8 weeks, small paddock turnout for 4–8 weeks, and gradual return to exercise with in-hand walking beginning two weeks postoperatively.
106
What are the % of horses retunring to work with concurrent DDFT tears of SDFT tears?
Horses with injury to the digital flexor
tendons have lower rates of return to previous levels of
exercise than the horses in this study (61% with SDFT
tears and 37%–42% with DDFT tears
manica flexoria tears have similar
results with 56 to 79% returning to preinjury exercise
107
What most common?
A. PAL constriction>MF tear> DDFT tear
B. PAL constriction>DDF tear> MF tear
C. MF tear >Palmar constriction> DDFT tea
108
F I G U R E 1 Transverse ultrasound (US) images of the plantar metatarsal region, obtained proximal to the proximal sesamoid bones in
a non–weight-
bearing
position showing images acquired from patients with a MF tear (medial is to the left of the images). (a) US image
showing the torn edges of the MF floating within the synovial fluid on the side of the MF tear (arrow). (b) US image showing the recoiling of
the MF on the side contralateral to the tear (arrowhead). (c) US image showing the increased distance between medial borders of the SDFT
and DDFT on the side where MF is torn (*). 1 Skin and subcutaneous tissue, 2 SDFT, 3 DDFT, 4 MF. DDFT, Deep digital flexor tendon; MF,
Manica flexoria; SDFT, Superficial digital flexor tendon
108
Fonseca et al 2019 VRU What was the most common ultrasonographic finding at the static weight-bearing examination in horses with a partial manica flexoria tear?
a) Asymmetrical appearance of the superficial digital flexor tendon.
b) Reduced sliding of the deep digital flexor tendon.
c) An incomplete visualization of the manica flexoria.
a) Asymmetrical appearance of the superficial digital flexor tendon at the junction with the lateral border of the superficial digital flexor tendon.
109
FIGURE 2 Transverse ultrasound images of the plantar
metatarsal region obtained proximal to the proximal sesamoid
bones in a non–weight-
bearing
position (medial is to the left of the
images). The image was acquired from a patient with a complete
MF tear. Note the increased distance between medial borders of
the SDFT and DDFT on the side where the MF is torn (*). Also note
the increased gap between MF and DDFT (arrowhead). 1 Skin and
subcutaneous tissue, 2 SDFT, 3 DDFT, 4 MF. DDFT, Deep digital
flexor tendon; MF, Manica flexoria; SDFT, Superficial digital flexor
tendon
110
FIGURE 3 Transverse ultrasound images of the plantar
metatarsal region, obtained proximal to the proximal sesamoid
bones in a non–weight-bearing position (medial is to the left of the
images). This US image was acquired from a patient that presented
with an acute MF tear. Note the torn edges of the MF floating
within the synovial fluid on the side of the MF tear (arrowhead). 1
subcutaneous tissue, 2 SDFT, 3 DDFT, 4 MF. DDFT, Deep digital
flexor tendon; MF, Manica flexoria; SDFT, Superficial digital flexor
tendon
111
Hibner 2022 US can be used to predict location of manica flexoria tears The location of the MF tear was correctly predicted in:
A. 40%
B. 72 %
C. 84%
D. 91%
91%
112
Tenoscopy is to the date the preferable treatment. Waht do you have to do in case of tear? how do you perform?
All tears → complete resection (debridement assoc. with poor outcome, Findley 2012)
*PAL desmotomy can be performed first (via standard proximal instrument portal)
*If lateral recumbency
-All portals created ipsilaterally § Second instrument portal: lateral at level of distal end of MF, between DDFT and SDFT
-Transect lateral MF border using a #12 blade or 14G needle
-3rd instrument portal in proximal part ofthe DFTS → rongeur to grasp distal and lateral edge of MF → apply tension →SDFT rolls medially § Resection of medial border, dorsal to DDFT using arthro scissors, 14G needle, hook knife, or biopsy punch
113
Which type of DDFT tears are described as "long (>7 cm)"?
a) Longitudinal DDFT tears
b) Lateral DDFT tears
c) Medial attachment MF tears
a) Longitudinal DDFT tears
114
What is the characteristic feature of "Medial attachment MF tears"?
a) Tears involving the deep layers of the DDFT
b) Tears extending laterally along the DDFT
c) Tears at the medial attachment of the SDTF
c) Tears at the medial attachment of the SDTF
115
Cender et al 2022 Which structure within the DFTS was most commonly diagnosed with lesions in this study?
a) Deep digital flexor tendons (DDFT).
b) Superficial digital flexor tendons (SDFT).
c) Manica flexoria (MF).
a) Deep digital flexor tendons (DDFT).
116
Cender et al 2022 Which diagnostic imaging technique showed higher sensitivity for diagnosing MF and DDFT tears?
a) Ultrasonography.
b) Contrast tenography.
c) Both had the same sensitivity
b) Contrast tenography
117
Cender et al 2022 What percentage of horses were able to return to the same or higher level of exercise following tenoscopic surgery for nonseptic tenosynovitis of the DFTS?
a) 15.3%
b) 33.8%
c) 50.8%
c) 50.8%
118
Cender et al 2022 What was the outcome for horses with DDFT lesions in terms of returning to the same or higher level of exercise?
a) 15.3%
b) 36.6%
c) 50.8%
b) 36.6%
119
Cender et al 2022 How were the contrast tenography evaluated in the article?
Briefly, contrast accumulation dorsal to the DDFT at the levelof the MF and/or the presence of one instead of two radiopaque linesat the level of the MF and/or the dorsal of the two parallel lines notextending distally to meet the proximal border of the proximal sesamoidbones was indicative of a MF tear. Longitudinal DDFT tearswere suspected if a longitudinally oriented accumulation of contrastwas present within the outline of the DDFT, at the level of or distal tothe proximal sesamoid bones
120
Cender et all VS 2020 Ex vivo evaluation of an alternative technique for resectionof the proximal manica flexoria in horses Where is the landmarks for the portals?
A stab incision was made with a No 11 bladeinto the distended pouch between the palmar/plantar annularligament and the proximal digital annular ligament at the baseof the proximal sesamoid bone, 3 to 6 mm palmar/plantar tothe digital neurovascular bundle.
2 portals for instruments one ipsilateral and 1 contralateral in the proximal aspect
121
Cender et all VS 2020 How many steps were involved in the MF resection procedure described in the study?a) Four steps.b) Six steps.c) Twelve steps
b) Six steps.
122
Cender et all VS 2020 What was the median time required for MF resection in the study?a) 6 minutes 42 seconds.b) 14 minutes 54 seconds.c) 43 minutes 33 seconds.
b) 14 minutes 54 seconds.
123
Cender et all VS 2020 describe the 6 steps
1. Resection of the first longitudinal lateral/medial MF border.
2. Resection of the proximal border.
3. The micro scalpel was removed, and a curved Halsted-Mosquito forceps was introduced through the proximal
instrument portal and used to grasp the free longitudinal margin of the MF to maintain tension on the tissue.
4. An additional portal was created for the arthroscope at the base of the sesamoid bone on the contralateral side.
5. The second longitudinal lateral/medial MF border was resected with a hook knife under endoscopic guidance
by using the same technique described in step
1 (Figure 4).
6. The resected MF was removed through the first instrument
portal by using the Halsted-Mosquito forceps
placed in step 3.
124
125
126
Diekstall 2020 Tenoscopic resection of the manica flexoria in 21 horses using a two-portal unilateral techniqueWhat is the primary advantage of the two-portal technique for manica flexoria resection compared to the multiple portal approaches?
a) It provides a higher success rate.
b) It requires fewer portals, reducing invasiveness.
c) It reduces the need for surgical instruments
b) It requires fewer portals, reducing invasiveness.
127
What percentage of the operated horses in the clinical study were able to return to their pre-injury level using the two-portal technique for manica flexoria resection?
a) 21%
b) 71%
c) 100%
b) 71%
128
Figure 92-31. Illustration of tenoscopic annular ligament release, using a slotted cannula inserted from proximal, and an arthroscope inserted from distal to the base of the sesamoid to visualize a 90 degree–angled blade used to sever the fibers of the annular ligament. Inset shows the position of the blade adjacent to the sesamoid abaxial perimeter.
129
Figure 92-34. Torn manica flexoria of the SDF tendon (SDFT). (A) Ultrasonographic appearance showing the retracted mass (arrow) alongside the DDF tendon (DDFT). (B) Tear along the medial side of the manica (arrows). (C) Free portion of manica (MF) tear.
