Transverse Process Fractures¶

Definition¶

Transverse process fractures are fractures of the lateral bony projections of the vertebrae. They are most common in the lumbar spine and are generally considered stable, isolated injuries. However, they serve as important markers of significant trauma energy and are frequently associated with other injuries that require careful evaluation.

Mechanism of Injury¶

Transverse process fractures result from:

Direct trauma — A blow to the flank or paraspinal region
Forceful lateral flexion — Lateral bending of the spine beyond the normal range
Avulsion — Forceful contraction of the psoas major (lumbar) or paraspinal muscles

In the lumbar spine, the L1–L3 transverse processes serve as attachment sites for the psoas major, quadratus lumborum, and intertransverse muscles. Violent muscle contraction during trauma can avulse the transverse process.

Imaging Findings¶

CT¶

Fracture lines through the transverse process, often best seen on coronal and axial images
May be unilateral or bilateral, and may involve multiple contiguous levels
Displacement is variable — from non-displaced to significantly separated fragments
Evaluate for associated vertebral body fractures, pedicle fractures, and posterior element injuries

Radiography¶

Transverse process fractures are frequently missed on radiographs due to overlying bowel gas and soft tissues
When visible, they appear as lucencies through the transverse processes on AP view

Clinical Pearl

Isolated transverse process fractures are stable injuries, but they indicate that significant force was applied to the abdomen and flank. Lumbar transverse process fractures are strongly associated with renal injuries, retroperitoneal hemorrhage, and vascular injuries — particularly when L1–L3 transverse processes are involved on the left side (proximity to the kidney and spleen). CT of the abdomen and pelvis with contrast should be obtained when multiple lumbar transverse process fractures are present.

Classification¶

In the AO Spine system, isolated transverse process fractures are classified as A0 — minor, non-structural fractures that do not affect spinal stability.

Associated Injuries¶

Renal contusion, laceration, or pedicle injury (especially left-sided L1–L3 fractures)
Splenic or hepatic injury
Retroperitoneal hemorrhage (psoas hematoma)
Brachial plexus injury (cervical transverse process fractures)
Vertebral artery injury (cervical transverse process fractures involving the transverse foramina)
Other spinal fractures

Management¶

Isolated transverse process fractures are treated conservatively with analgesics, rest, and gradual return to activity. No bracing or surgical intervention is needed. Pain typically resolves within 4–6 weeks.

The primary clinical significance lies in identifying associated injuries that may require intervention.

Key Points¶

Transverse process fractures are stable, AO Type A0 injuries
Most common in the lumbar spine from direct trauma or lateral flexion
Frequently missed on radiographs — CT is much more sensitive
Multiple lumbar transverse process fractures should prompt evaluation for renal and retroperitoneal injuries
Cervical transverse process fractures may be associated with vertebral artery injury
Treatment is conservative for isolated injuries

References¶

Miller CD, Blyth P, Civil ID. Lumbar transverse process fractures — a sentinel marker of abdominal organ injuries. Injury. 2000;31(10):773–776. https://pubmed.ncbi.nlm.nih.gov/11154746/
Patten RM, Gunberg SR, Brandenburger DK. Frequency and importance of transverse process fractures in the lumbar vertebrae at helical abdominal CT in patients with trauma. Radiology. 2000;215(3):831–834. https://pubmed.ncbi.nlm.nih.gov/10831706/
Krueger MA, Green DA, Hoyt D, Garfin SR. Overlooked spine injuries associated with lumbar transverse process fractures. Clin Orthop Relat Res. 1996;(327):191–195. https://pubmed.ncbi.nlm.nih.gov/8641063/
Woodring JH, Lee C, Duncan V. Transverse process fractures of the cervical vertebrae: are they insignificant? J Trauma. 1993;34(6):797–802. https://pubmed.ncbi.nlm.nih.gov/8315673/
Peterson A, Behrens J, Salari P, Place H. Isolated thoracic and lumbar transverse process fractures: Do they need spine surgeon evaluation? A high volume level I trauma center experience with cost analysis. N Am Spine Soc J. 2023. https://pmc.ncbi.nlm.nih.gov/articles/PMC10407537/
Agrawal A, Srivastava S, Kakani A. Isolated transverse process fracture of the lumbar vertebrae. J Emerg Trauma Shock. 2009;2(3):217–218. https://pmc.ncbi.nlm.nih.gov/articles/PMC2776377/
Transverse process fracture. Radiopaedia.org. https://radiopaedia.org/articles/transverse-process-fracture