Chapter 53 - Vertebral column thorax coccygeal

Question 1

What type of vertebral injuries is more common in adult horses than in foals?

Answer 1

Thoracolumbar

Question 2

1.

In horses, life-threatening vertebral fractures are most often seen in what activity?

Answer 2

Jumping

Question 3

Which parts of the thoracolumbar spine are typically involved in fractures?

Answer 3

Vertebral body and dorsal spinous processes

Question 4

Where do the most common vertebral body fractures occur in horses?

Answer 4

First three thoracic vertebrae followed by T12

Question 5

What is the recommended course of action for horses with severe disruption of the thoracolumbar spinal cord?

Answer 5

Euthanasia

Question 6

Where do dorsal spinous process fractures tend to occur?

Answer 6

Thoracic vertebrae

Question 7

What therapeutic approaches can be attempted when the spinal cord is intact?

Answer 7

Conservative therapy or stabilization with pins/plates

Question 8

Fracture of the thoracic dorsal spinal processes in horses is often associated with what behavior?

Answer 8

Rearing and falling backward

Question 9

In a report of 22 cases of thoracolumbar vertebral fractures, how many involved the vertebral body or neural arch?

Answer 9

15

Question 10

What are common clinical signs of fractures of the dorsal spinous processes?

Answer 10

Local pain, swelling, and stiffness

Question 11

What surgical procedure is performed for fractures of the dorsal spinous processes?

Answer 11

Subtotal ostectomy

Question 12

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What is the preferred technique for the subtotal ostectomy of the dorsal spinous processes?

Answer 12

In the standing horse

Question 13

For what reasons might surgery be required for dorsal spinous process fractures?

Answer 13

Sequestered bone fragments or position precluding saddle use

Question 14

How long postoperatively is healing adequate to permit riding?

Answer 14

8-12 weeks

Question 15

What does consist the conservative tx of thoracic and lumbar spinous processes fracture?

Answer 15

systemic and intralesional cortico +
shockwave/radial pressure wave therapy,
bisphosphonates
+ acupuncture careffully inserted

Question 16

How do you perform the surgical intervention?

Answer 16

Surgical tx: sedation + local anesthesia nea incisionbut LR is preferred by most surgeons
Metalic markers forradio control ofexactly the sites of the DSPs to be resectedvLongitudinal inicision is made betweenthe most cranial and caudal of the affected DSPs
Supraspinous ligaments diveded sharply and longitudinally and retracted abaxially with Gelpi retractors
The dorsal part of DSP of 1 or morevertebra is resected àoscillating saw, osteotome, gigli wire
Gigli wire with custom-made wire guide is used hasess exposure and dissection is necessary which is why this is the preferredtechnique 2 types of procedure:
1.Resection of the entire DSP
2.Subtotal (cranial wedge) ostectomy(+ recent)
mandatory minimum of 5 mm between remaining bodies of each process resected

Question 17

describe partial resection

Answer 17

Partial resection of the thoracic and lumbar dorsal spinousprocesses
Thedorsal 4 to 5 cm of the DSPs are dissected free of the supraspinous ligament +interspinous ligaments + adjacent muscle tissue

For the cranial wedge osteoctomy: 1stinterspinous ligament cranial to each affected DSP is sharply incised
With oscillation saw onlythe cranial portion of affected DSPs is removed in a caudodorsal-cranioventraldirection
The ventral extent of the resectionshould emerge ventral to the site of impingement
Once the** resection is complete à supraspinous ligament issutured in simple continous pattern** – skin with staples

Question 18

In addition to radiography, which imaging modality is advised due to frequent oversight of fractures?

Answer 18

CT

Question 19

What is used to document the extent of spinal cord compression in foals, small horses, ponies, and donkeys?

Answer 19

Myelography

Question 20

What is the initial treatment for horses with little or no displacement of vertebral fragments?

Answer 20

Conservative management

Question 21

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When is implant fixation indicated in vertebral body fractures?

Answer 21

When needed to provide stability

Question 22

What position is the horse placed in for implant fixation surgery?

Answer 22

Sternal recumbency

Question 23

How are the Steinmann pins inserted for stabilizing a fracture?

Answer 23

At an angle to the vertebra

Question 24

What is critical to avoid when inserting the caudal pins?

Answer 24

Injuring the aorta and vena cava

Question 25

What provides final rigidity in the stabilization process?

Answer 25

Cold-curing PMMA

Question 26

Which diagnostic methods are used to examine back pain in horses?

Answer 26

Physical and complete orthopedic examination, including diagnostic analgesia, radiology, and scintigraphy

Question 26

What conditions have been associated with back pain in horses?

Answer 26

Overriding DSPs, osteoarthritis, spondylosis

Question 27

What is the common treatment for most horses with back pain?

Answer 27

Intralesional treatment with corticosteroids and agents like Sarapin

Question 28

What surgical technique is used for the resection of the dorsal part of the DSP in horses?

Answer 28

esection using an oscillating saw, osteotome, gigli wire, or bone-cutting shears

Question 29

Brown et al VS 2020 Long-term outcome and effect of diagnostic analgesia in horses undergoing interspinous ligament desmotomy for overriding dorsal spinous processe. Performance comparison of 159 Thoroughbred racehorses and matched cohorts before and after desmotomy of the interspinous ligamen- What was compared to determine the influence on long-term outcome? A) The type of ISLD performed B) The use of preoperative diagnostic analgesia C) The age of the horses D) The breed of the horses

Answer 29

B) The use of preoperative diagnostic analgesia

Question 30

What was the conclusion of the study regarding preoperative diagnostic analgesia? A) It has no effect on the long-term outcome B) It is detrimental to the long-term outcome C) It is likely to improve the long-term outcome D) It should be avoided as it complicates the surgery

Answer 30

C) It is likely to improve the long-term outcome

Question 31

Which recent complication has been reported following desmotomy of the interspinous ligament? A) Infection at the surgical site B) Hemorrhage during surgery C) Neurogenic atrophy of the contralateral epaxial muscle D) Complete recovery without side effects

Answer 31

C) Neurogenic atrophy of the contralateral epaxial muscle

Question 31

EVJ 2021 Derham et al Implications of the neuroanatomy of the equine thoracolumbar vertebral column with regional anaesthesia and complications following desmotomy of the interspinous ligament What are impinging/overriding dorsal spinous processes (DSPs) of the thoracolumbar vertebrae known to cause in horses? A) Improved performance B) Poor performance C) Increased flexibility D) Better balance

Answer 31

B) Poor performance

Question 32

What do the authors suggest as the cause of this complication? A) An allergic reaction to medication B) A more lateral approach than previously described, possibly transecting a nerve C) Poor surgical technique D) Inadequate postoperative care

Answer 32

B) A more lateral approach than previously described, possibly transecting a nerve

Question 33

What is hypothesised to be the cause of post-operative neurogenic atrophy? A) Transection of an intermediate branch of the dorsal spinal nerve supplying the m. longissimus B) Genetic predisposition to muscle atrophy C) The horse's activity level post-surgery D) Age-related muscle degeneration

Answer 33

A) Transection of an intermediate branch of the dorsal spinal nerve supplying the m. longissimus

Question 33

What does the review article highlight regarding the equine thoracolumbar region? A) There is an abundance of detailed knowledge about neural anatomy B) Surgical techniques in this area are well-standardized C) There is a lack of anatomical knowledge in the literature D) Local anaesthesia is always effective in localising pain in the equine back

Answer 33

C) There is a lack of anatomical knowledge in the literature

Question 34

Prisk et al VS 2019 Long-term prognosis for return to athletic function after interspinous ligament desmotomy for treatment of impinging and overriding dorsal spinous processes in horses: 71 cases (2012-2017) - What percentage of horses returned to some level of performance post-ISLD? A) 37.5% B) 52.9% C) 78.6% D) 91.1%

Answer 34

D) 91.1%

Question 35

Prisk et al VS 2019 What did the study conclude about the influence of radiographic and scintigraphic grades on the return to performance? A) They are strong predictors of return to performance B) They have no influence on the return to performance C) Only radiographic grades are influential D) Only scintigraphic grades are influential

Answer 35

B) They have no influence on the return to performance

Question 36

de Souza et al. 2021 (Vet Surg) - Minimallyinvasive cranial ostectomy for the treatment of impinging dorsal spinousprocesses in 102 standing horses- Main important factor is the rongeur. What are themeasurements?

Answer 36

Cranial ostectomy of theCAUDAL DSP with Stille Lueror Leksell-Stille bone rongeurs ●4-8 bites, ensure >5mm gap achieved, 4 cm depth● ●Dimensions of rongeurs CRUCIAL 20-24cm length, jaw length 20-30mm, jaw width 10-15mm

Question 36

Prisk et al VS 2019 What was the satisfaction level among owners regarding their horses' postoperative performance levels? A) 37.5% B) 52.9% C) 78.6% D) 82.1%

Answer 36

C) 78.6%

Question 37

What percentage of horses had complete resolution of clinical signs and returned to intended work after the procedure? A) 69% B) 80% C) 93% D) 100%

Answer 37

B) 80%

Question 38

What typically causes trauma to the sacral area in horses?

Answer 38

Suddenly dog-sitting or falling over backward

Question 38

What are the symptoms of compressive lesions of the sacrum in horses?

Answer 38

Pain and swelling over the croup and tail head, tail weakness or paralysis, decreased anal tone, retention of feces, bladder distention, and urine dribbling

Question 39

# ``` How are sacral area injuries in horses initially treated?

Answer 39

With antiinflammatory drugs and observation for up to 10 days

Question 40

What is the recommended action if there is no improvement in the horse's condition after 10 days of an acute sacral injury?

Answer 40

Consider surgical intervention or euthanasia

Question 41

What surgical procedure can be performed for decompression of the sacrum in horses?

Answer 41

Surgical decompression by removing the spinous processes and dorsal laminae of the sacral vertebrae

Question 42

How many coccygeal vertebrae do horses typically have?A) 10B) 16C) 18D) 20

Answer 42

C) 18

Question 43

What is a common consequence of trauma to the base of the tail in horses?

Answer 43

Vertebral fracture, soft tissue injury, and neurapraxia of the motor nerves

Question 44

What diagnostic tool is useful for evaluating tail fractures in horses?

Answer 44

Radiographs

Question 44

Answer 44

Figure 53-24. Horse that sustained multiple fractures of the dorsal spinous processes and was treated conservatively. Note the flat contour of the withers.

Question 45

Answer 45

Figure 53-25. Laterolateral radiographic view showing fracture (arrows) of the dorsal spinous processes.

Question 46

Answer 46

Figure 53-27. Three dimensional–computed tomography reconstruction of a comminuted fracture (arrow) of the second thoracic vertebra in a horse that ran into a tree and was paralyzed immediately after the injury.

Question 47

Answer 47

Figure 53-28. (A) Laterolateral radiographic view showing impingement of the thoracic dorsal spinous processes in a sport horse (arrow). (B) Laterolateral radiographic view during preparation for surgery (spinal needles were inserted between the dorsal spinous processes, and skin staples were used to assist in the identification of the involved spinous processes. (C) Laterolateral radiographic view taken immediately after surgery. (D) Laterolateral radiographic view taken 1 year postoperatively showing excellent healing without complication; no bony reactions are noted at the insertion point of the interspinous ligament.

Question 47

How do you manage a worse with cocygeal fracture?

Answer 47

Most horses with fractures of the coccygeal vertebrae are managed conservatively with stall rest and the use of antiinflammatory drugs

Question 47

What are the options for coccygeal fractures treatment?

Answer 47

1. Closed fracture is conservative 2. open fracture = debridement with longitudinal incision dorsal or ventral 3. Tail amputation

Question 48

Answer 48

Figure 53-29. (A) Intraoperative view of fixation of a comminuted fracture of the sacrum using a narrow 6-hole 4.5/5.0-mm locking compression plate. (B) Laterolateral radiographic view of the horse shown in Figure 53-45 taken immediately postoperatively.

Question 49

Describe the tail amputation

Answer 49

Epidural and local anesthesia Standing under sedation A penrose drain or Esmarch bandage is placed tightly around the most cranial aspect of the tail to reduce hemorrhage during surgery. Two flaps are created from the dorsal and ventral ends of the skin. The points of these flaps are facing caudally and should be located caudal to the site of amputation to allow enough soft tissue for wound closure. A scalpel is used to transect between two coccygeal vertebrae at the site of the amputation. Disc material and cartilage is removed with a curette to expose a vascularized bony surface that supports healing. The subcutaneous tissues and skin are closed in routine fashion. A stent bandage is applied to the incision and covered with an adhesive barrier drape to keep the area clean and dry during recovery from anesthesia

Question 50

Answer 50

Question 51

Which spinal cord segments are suggested to be intact if a mare has normal micturition and defecation without hind limb ataxia?

Answer 51

S1-S4

Question 52

Injury to which spinal cord segments can result in abnormal micturition and defecation in horses?

Answer 52

Sacral segments S1-S4

Question 53

The mare's lack of sensation to the perineum and initial absence of anal tone suggest damage to which nerve?

Answer 53

Caudal rectal nerve

Question 53

The lack of sensation and motor function to the tail are likely due to damage to which nerve?

Answer 53

Coccygeal nerve

Question 53

What is a major concern following the complete amputation of a horse's tail?

Answer 53

Lack of insect control.

Question 54

What type of trauma does the presence of a hematoma in the tail suggest?

Answer 54

Tension-induced trauma to blood vessels

Question 55

What is used for fixation in the treatment of cranial coccygeal fractures?

Answer 55

Locking compression plates (LCPs) and/or pins

Question 56

Which of the following are examples of malformational abnormalities?

Answer 56

Hemivertebrae, butterfly vertebrae, and block vertebrae.

Question 57

What may asymmetric fusion between the atlas and the occipital bones lead to?

Answer 57

The development of scoliosi

Question 58

The dens of the axis in horses with OAAM is typically what?

Answer 58

Hypoplastic.

Question 58

In which breed is OAAM most frequently reported?

Answer 58

Arabian foals.

Question 59

What clinical sign may be elicited by manipulating the head of a horse with OAAM?

Answer 59

A clicking sound.

Question 60

How do clinical signs of OAAM progress over time?

Answer 60

They worsen due to repetitive or persistent spinal cord compression

Question 61

What is required for a definitive diagnosis of OAAM?

Answer 61

A systematic neurological examination and two orthogonal radiographic views.

Question 62

Which imaging modalities are best for evaluating OAAM?

Answer 62

CT and MRI.

Question 63

When is OAAM typically detected?

Answer 63

At birth or within the first few weeks of life.