Case Studies

Broken Lower Back

Broken Lower Back Case Study Radiograph 1

A 3 year old, 73 lb German Shepherd Cross presented with rear leg paralysis with deep pain on one side on admission. Patient was losing deep pain perception pre-operatively. Radiographs (lateral only) show slight crack in L1 and fracture of L6 with severe displacement. Solumedrol was administered pre-operatively. Owner understands guarded prognosis but wants to go ahead with surgery. This case was operated on at midnight since waiting any longer would have created potentially irreversible damage to the spinal cord.

Emphasis

Spinal injuries and associated neurologic dysfunction are encountered frequently in small animal practice. Such injuries are most often the result of automobile trauma, or less commonly gunshot injuries, fall from heights, or animal abuse. Ligamentous failures result in spinal luxations, which may occur without associated fractures. 12% of cases also have concomitant disc prolapse at the injury site or elsewhere. Thorough, serial neurologic examinations are a critical component of patient care and prognosticating so that you and the owner can make informed decisions regarding medical treatment, surgical treatment, or euthanasia. Many patients with subluxations and severe spinal cord trauma can have very normal looking radiographs, especially if only a lateral view is taken.

Axiom

Broken Lower Back Case Study Radiograph 2

All car accident patients should be considered to have thoracic trauma, cardiac trauma, and a ruptured urinary system until proven otherwise. 38% of pelvic fracture patients have concomitant neurologic or urinary system damage. Urinary catheters should be placed in all patients (male and female). If needed, double contrast dye studies of the bladder should be performed. Use a Foley catheter placed distally in the urethra or vaginal vestibule to perform a urethrogram as well as a cystogram. 2-view thoracic and abdominal radiographs are essential for all trauma cases. ECG evaluation often will show myocardial injury with resultant cardiac arrhythmias as well as elevated liver enzymes from traumatic hepatopathy. Always move this type of patient on a board or a suitable support to prevent additional spinal cord damage.

Broken Lower Back Case Study Radiograph 3
Broken Lower Back Case Study Radiograph 4

Post operative films show the reduction and stabilization accomplished utilizing a large plastic lubra plate (Sontec). Unlike the old stainless steel spinal plates, these plates are flexible and hold the dorsal process by friction. Note the bolts are placed between the processes instead of through them. Pressure necrosis is eliminated by utilizing this technique as well as spinal column flexibility side to side. The transilial threaded rod adds additional stability by tying in the plate to the ilial wings as the L7 and sacral processes are smaller and do not afford a lot of stability to the distal plate. This patient was walking in eight days and two months post-operatively is doing very well with no neurological deficits or pain.

Spinal Fracture Luxation

A 1 year old, 78 lb Chocolate Lab with rear leg paresis and good deep pain on both legs on admission was seen. Radiographs show fracture/luxation of L6-L7 with ventral displacement of both in shape of "V". Caudal end plate of L6 has chip fracture. Dorsal processes of L6 and L7 fractured off body and dorsal roof of L6 is included with process. Solumedrol administered pre-operatively. Owner understands the surgery is exploratory in nature without a CT or MRI pre-operatively to evaluate the cord. In addition, surgical manipulation and reduction can cause his neurological condition to deteriorate.

Spinal Fracture Luxation Radiograph 1
Spinal Fracture Luxation Radiograph 1
Spinal Fracture Luxation Radiograph 1

This repair was similar to case 1 but I elected to use cross pins instead of the threaded transilial rod as the holes did not line up well and I was concerned about weakening the plate by drilling a new hole close to the existing one. The patient was standing three days after surgery and walking by two weeks. By two months he was doing very well with no neurological deficits or pain.


Sacroiliac Luxation Bilateral With Pelvic Fracture

A 1 year old, 10lb Jack Russell Terrier was run over by his owner and suffered bilateral SI joint luxations and a left ilial fracture. Urethrogram/cystogram was normal as were neurologic reflexes.

Axiom

A significant percent of SI luxations will heal without surgery but be aware that if a large callous forms it can entrap the sciatic nerve and cause irreparable chronic pain that usually necessitates euthanasia. If there is minimal displacement, take another radiograph in five days to see if the pelvis has shifted before continuing conservative treatment. Similarly, since the sciatic nerve traverses directly under the medial aspect of the ilial body, large callous formation can entrap the nerve here as well. Sharp bone edges can damage or sever the nerve with over activity. Additionally, early ambulation can push the ilial segment medially creating a narrow pelvic canal that can cause dysuria and obstipation. Patients treated surgically heal faster, ambulate faster, and pain diminishes much faster.

Sacroiliac Luxation Bilateral With Pelvic Fracture Radiograph 1
Sacroiliac Luxation Bilateral With Pelvic Fracture Radiograph 2

Most people use the transilial rod as an adjunct to a sacral compression screw. I have found that if you place a small k-wire or IM pin across the wings to provide a second point of fixation, the compression created from this apparatus is more than adequate to stabilize these fracture/separations. If there is a sacral fracture, I will run an additional small pin or k-wire across the sacrum with an aiming device. You do not need perfect reduction for these patients to do well. You are just trying to prevent movement and exuberant callous formation.

You do not need any special equipment to place this rod and I would gladly send you further information if you want to attempt to use this rod on a surgery.