Burst Frx of Spine : Wheeless' Textbook of Orthopaedics

- Discussion:
- fall from a height, landing on one's feet, is typical of this fracture;
- burst frx involve only compressive failure of vertebral body both anteriorly & posteriorly, w/ failure of both anterior & middle columns;
- axial loading applied to intravertebral disc results in increased nuclear pressure and hoop stresses in the annulus;
- this results in a high shear stress on the vertebral end plate at inner border of the annulus, away from center of disc;
- a large central posterior-superior fragment occurs as a result of these forces;

- Burst Frx Location:
- Cervical Burst Frx
- Lumbar Burst Frx:
- Thoracic Burst Frx:
- Thoracolumbar Burst Frx:

- Classification: (stable or unstable)
- stable frx:
- neurologically intact;
- posterior arch remains intact: pedicle widening implies post arch disruption w/ instability;
- less than 50% anterior body height collapse:
- compression fractures:
- unstable frx:
- neurologic deficit;
- loss of 50% of vertebral body height;
- fracture dislocation:
- thoracolumbar burst frx:
- angulation of the thoracolumbar junction > 20 deg
- canal comprimise > 30 percent

- Examination:
- inaddition to the orthopaedic examination, the patient should be evaluated for an ileus;

- Radiographs and Classification
- in thoracolumbar burst frx, look for comminution of the postero-superior corner of vertebral body;
- good quality AP radiographs are necessary to visualize the posterior elements;
- ensure that appropriate radiographs have been taken to rule out other concomitant injuries (such as pelvic frx);

- CT scan:
- allows assessment of canal comprimise and better visualization of posterior element injury;

- Initial Managment:
- see: management of spine injured patient
- w/ neurologic injury steroids may be indicated;
- its essential that the patient be log roled off the trauma board as soon as possible (inorder to avoid devastating pressure ulceration);
- ileus (common associated condition);
- in some cases an NG tube is required for severe ileus;
- if bowel sounds and flatus are not present then patient should be made NPO, and should receive IV fluids;

- Non Operative Treatment:
- most stable burst fractures and most lumbar burst fractures can be treated non operatively;
- w/ non operative treatment, significant remodeling and reabsorption (about 50%) of retro-pulsed fragments can be expected to occur;
- relative contra-indications:
- unstable burst frx;
- morbid obesity
- presence of associatted conditions which would preclude brace wear;
- total contact orthosis (w/ or w/o hyperextension) is worn for 4-6 months;
- leg extension must be added for fractures below L3;
- typically patients are allowed out of bed 3 to 14 days after injury, unless there are other concomitant injuries such as pelvic frx;
- whereas initial radiographs are taken supine, w/ long term follow up, radiographs need to be taken standing to evaluate for kyphosis;
- reference:
- Conservative treatment of fractures of the thoracic and lumbar spine.
- Nonoperative treatment of thoracic and lumbar spine fractures: a prospective randomized study of different treatment options.

- Operative Treatment:
- Posterolateral Decompression
- most indicated for unstable burst frx w/ cord impingement along w/ dural tear and nerve root entrapment from frx of posterior elements;
- Posterior Distraction Systems:
- Pedical Screw Implants:
- Anterior Decompression and Fusion
- most indicated for unstable burst frxs w/ cord impingement caused by bone fragments off the postero-superior vertebral body