Lumbar Artery Pseudoaneurysm in Traumatic Spinal Cord Injury: A Case Report Kwai-Tung Chan, MD, Naveen Korivi, DO ABSTRACT. Chan K-T, Korivi N. Lumbar artery pseudoaneurysm in traumatic spinal cord injury: a case report. Arch Phys Med Rehabil 2003;84:455-7. Lumbar artery pseudoaneurysm is a rare vascular complication of trauma. This case report concerns a 24-year-old man with a lumbar-level spinal cord injury (SCI) secondary to a gunshot wound who developed severe exacerbation of low back and flank pain during inpatient rehabilitation. Diagnostic investigations at an acute care hospital revealed a left lumbar artery pseudoaneurysm. This was treated by transcatheter embolization, which resulted in a marked reduction in pain. The patient resumed inpatient rehabilitation without further complications. This case report highlights the importance of early diagnosis of lumbar artery pseudoaneurysm, a potentially fatal complication that can occur in patients with traumatic lumbosacral SCI. Physiatrists should include lumbar artery pseudoaneurysm in the differential diagnosis for back, flank, or abdominal pain in this patient population. Key Words: Case report; Lumbar region; Pseudoaneurysm; Rehabilitation; Spinal cord injuries; Trauma. © 2003 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation ATIENTS WITH TRAUMATIC lumbosacral spinal cord injury (SCI) may report low back, flank, or abdominal pain P while undergoing inpatient rehabilitation. The differential diagnosis of such pain in this population is extensive and includes pathology within the abdomen and pelvis and the abdominal or pelvic wall, recent surgery, and nerve root or peripheral nerve injuries. Lumbar artery pseudoaneurysm is an uncommon intra-abdominal complication that can result in back, flank, or abdominal pain. Lumbar artery pseudoaneurysm has been described in patients with blunt abdominal trauma, gunshot and stab wounds, lumbopelvic fractures, and bleeding disorders.1-6 It has been reported as a complication of renal biopsy and chiropractic manipulation7-9 and has occurred without any known predisposing factors.10 Lumbar artery pseudoaneurysm can result in potentially fatal hemorrhage if not diagnosed and treated promptly.1,10 This report describes its occurrence in a patient with traumatic lumbar-level SCI and discusses its clinical presentation, diagnosis, and treatment.
From the Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, TX. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated. Correspondence to Kwai-Tung Chan, MD, Dept of Physical Medicine and Rehabilitation, Quentin Mease Hospital, 3601 N MacGregor Way, Ste 202, Houston, TX 77004, e-mail: [email protected]
Reprints are not available. 0003-9993/03/8403-7275$30.00/0 doi:10.1053/apmr.2003.50029
CASE DESCRIPTION A 24-year-old man sustained a single gunshot injury to the left lumbar region that resulted in paraplegia. He was diagnosed with a L1 American Spinal Injury Association (ASIA) Impairment Scale class C SCI on admission to a level I trauma center. Computed tomography (CT) imaging of the lumbar spine revealed a bullet at the L3-4 intervertebral disk space, with multiple bony fragments within the spinal canal and a fracture of the anterior-inferior aspect of the L3 vertebral body. There was also a small left psoas hematoma. An abdominal aortogram showed no acute injuries to that aorta or to major branch vessels. The patient was conservatively managed with prophylactic intravenous antibiotics and a thoracic lumbar sacral orthosis for activities out of bed. The patient was transferred to an inpatient rehabilitation facility after 5 days in the trauma hospital. The patient’s SCI status remained as L1 ASIA class C on his admission to the rehabilitation unit. His only complaint was of mild left low back pain, with occasional radiation of pain down the left leg. His symptoms were initially attributed to musculoskeletal injury from the gunshot, with possible involvement of the lumbosacral nerve roots. He was treated with analgesic medications, which gave him adequate relief. The patient participated in physical and occupational therapies without difficulty and reported only intermittent exacerbations of pain during transfers. On day 9 of inpatient rehabilitation, he complained of a severe exacerbation of the low back and flank pain and the onset of pain in the left groin. He also developed diarrhea and fever (40°C). Physical examination was significant for tenderness of the left lumbar paraspinal muscles and left lower abdominal quadrant. The abdominal pain was exacerbated by passive range of motion of the left hip. White blood count was 35,000/mm3, and his hemoglobin level was stable at 14.7g/dL. Urine analysis and blood cultures were normal. Because of the worsening back and groin pain, fever, leucocytosis, and a recent history of penetrating gunshot wound to the lumbar region, clinical suspicion was high for an intra-abdominal abscess. After transfer back to the trauma hospital, the patient was believed to have a retroperitoneal infection or Clostridium difficile colitis. Empiric treatment with metronidazole was started. CT imaging of the abdomen showed an enlargement of the left psoas muscle, with extension into the pelvis (fig 1). An abdominal angiogram revealed a left third lumbar artery pseudoaneurysm (fig 2). The pseudoaneurysm was treated with transcatheter placement, under fluoroscopic guidance, of microcoils into the left third lumbar artery. Subsequent digital subtraction angiography confirmed complete occlusion of the pseudoaneurysm. The patient’s back and groin pain decreased significantly after the coil embolization procedure. Results of other procedures, such as blood cultures, stool cultures, and clostridium toxin assays, were negative. After a short stay in the acute care hospital, the patient was readmitted to the inpatient rehabilitation unit, resumed his rehabilitation without further complications, and was discharged home. Arch Phys Med Rehabil Vol 84, March 2003
LUMBAR ARTERY PSEUDOANEURYSM IN SCI, Chan
Fig 1. Axial CT of the abdomen with contrast shows a well-defined contrast collection in the left paraspinal soft tissue at the level of the L3 vertebral body. Note the enlargement of the left psoas muscle (arrows).
DISCUSSION Pseudoaneurysms are pulsatile hematomas that are in communication with an arterial lumen.3,11,12 In contrast to bleeding from other intra-abdominal vascular structures, bleeding from the lumbar arteries is often initially contained by the surrounding retroperitoneal tissues, which act as a tamponade to form a pseudoaneurysm.2-5 The lumbar arteries of L1 to L4 are small paired vessels that originate from the dorsal aspect of the abdominal aorta at the level of the transverse processes. The lower lumbar arteries can occasionally originate from a common trunk near the midline of the posterior aorta. The fifth lumbar artery may branch off the lateral sacral artery, iliolumbar artery, or median sacral artery. These vessels run laterally along the bodies of the lumbar vertebrae and divide into anterior and posterior branches at the medial border of the psoas muscle. There is a complicated network of lumbar arterial collaterals within the muscles of the back and on the outside and inside of the vertebral canal. Lumbar arteries also communicate with the superior and inferior epigastric arteries, the lowest intercostal and subcostal arteries, and the iliolumbar and lateral sacral branches of the internal iliac artery.1,10,13,14 The lumbar arteries and their collateral vessels provide circulation to the back musculature, the lower spinal cord, the lumbar vertebrae and their supporting structures, and to the dorsal root ganglia and nerve roots of the cauda equina. The lumbar plexus arises within the psoas muscle, and any of its branches, or the plexus itself, can be affected by an expanding mass within the muscle.15 This can cause pain and neurologic deficits in the distribution of the affected nerves. Lumbar artery pseudoaneurysms can remain asymptomatic or can present with variable signs and symptoms. Pain is the most common symptom and is believed to result from the stretching of surrounding nerves or from rupture of the pseudoaneurysm.2 Pain can be felt in the back, flank, or abdomen, depending on the location and extension of the lumbar artery pseudoaneurysm. The time between injury and onset of symptoms is variable, with delays of up to 18 months having been reported.3 Lumbar artery pseudoaneurysm can also present as a pulsatile mass with an audible bruit and a palpable thrill.3 Arch Phys Med Rehabil Vol 84, March 2003
Early diagnosis of lumbar artery pseudoaneurysm is important because complications such as aneurysmal expansion, rupture, hemorrhage, thrombosis, embolization, and ischemia can occur.1-10 Bleeding from the lumbar arteries can occasionally lead to life-threatening retroperitoneal hemorrhage. Unfortunately, diagnosis of lumbar artery pseudoaneurysm can be difficult for many reasons. These include nonspecific symptomatology and signs, an unawareness of this condition, delayed presentation, and neglecting the condition in the extensive differential diagnosis. There are also unique challenges in the diagnosis of abdominal pathology in patients with SCI.16,17 Retroperitoneal bleeding can result from injuries to other abdominal vascular structures, such as the abdominal aorta and inferior vena cava and their branches, as well as to the lumbar arteries. Bleeding can also occur from injuries to retroperitoneal gastrointestinal, genitourinary, or musculoskeletal structures.2 Inflammatory, neoplastic, or infectious lesions of the psoas muscle and other retroperitoneal pathology can present with pain locations similar to those found in lumbar artery pseudoaneurysm.3 The deep retroperitoneal location of lumbar artery pseudoaneurysm may result in poorly localized and nonspecific symptoms. As reported here, the clinical presentation of lumbar artery pseudoaneurysm can be delayed; conse-
Fig 2. Angiogram of the aorta, iliac vessels, and lumbar arteries. Note the left third lumbar artery pseudoaneurysm (arrows).
LUMBAR ARTERY PSEUDOANEURYSM IN SCI, Chan
quently, the condition should be considered in the differential diagnosis even if initial angiography does not show active bleeding. The response of an SCI patient to abdominal pathology will vary, depending on the neurologic level and degree of the injury and on whether reflexes distal to the lesion are intact.17 Abdominal pain, if present, may be dull and poorly localized. Pain may be referred from visceral structures to other sites with the same embryonic origin or neurologic segment as the involved organ.16 Symptoms from common complications such as urinary tract infections or constipation can be confused with symptoms resulting from other intra-abdominal pathology. Intra-abdominal disease may result in increased abdominal wall spasticity that can make tactile examination of the abdomen difficult. Inflammatory responses such as fever and leucocytosis may be absent or may develop late.17 Patients with SCIs above the T6 neurologic level are more likely to have atypical presentations of abdominal pathology.17 Plain radiographs can reveal fractures of the pelvis, lumbar vertebrae, or lower ribs and suggest an associated retroperitoneal hematoma.2 Suspicion of lumbar artery pseudoaneurysm should be heightened in symptomatic patients with these fractures. CT contrast imaging is useful in diagnosing retroperitoneal bleeding in stable patients with abdominal or pelvic injuries and suspected vascular injuries.1-10 A homogenous high-density mass on CT imaging is suggestive of a blood collection. Arteriography is useful for detecting active bleeding in the stable patient. It can often diagnose a pseudoaneurysm without need for a laparotomy, and it can result in immediate treatment by transcatheter embolization once the diagnosis has been made. The indications for abdominal arteriography in patients with lumbar spine and pelvic fractures include large retroperitoneal hematoma seen on CT imaging or discovered during laparotomy, persistent hypotension after fluid challenge associated with a negative peritoneal lavage, and massive hemorrhage requiring transfusion of more than 4 to 6 units of blood in 24 hours with a negative peritoneal lavage.1 After blunt abdominal trauma, selective visceral arteriography has been recommended to detect active bleeding in stable patients with retroperitoneal hematoma on CT imaging or when an active source of retroperitoneal bleeding cannot be identified during emergency laparotomy.2 Lumbar artery pseudoaneurysm should be treated as soon as it is detected because of its tendency to expand and bleed. Traditionally, surgical exploration and treatment has been advocated, but this can be technically difficult.3,4,10 Transcatheter embolization of the lumbar artery pseudoaneurysm under radiographic guidance may be a preferred treatment because it avoids morbidity from open surgical repair and the need for general anesthesia, and it is a safe and effective procedure for controlling the hemorrhage.1,2,4,5,7,8,10 CONCLUSION Lumbar artery pseudoaneurysm is a rare intra-abdominal complication of trauma; it presents with low back, flank, or abdominal pain. Physiatrists should include this condition in
the differential diagnosis of persistent or worsening back, flank, or abdominal pain in patients with traumatic lumbosacral SCI or recent trauma to the abdomen, flank, or pelvis. Abdominal CT of the abdomen and pelvis should be considered to investigate the source of symptoms in these patients. When retroperitoneal bleeding is detected by imaging studies, arteriography can confirm the diagnosis of lumbar artery pseudoaneurysm. Early diagnosis and treatment of this condition may prevent the development of potentially life-threatening complications. References 1. Sclafani SJ, Florence LO, Phillips TF, et al. Lumbar arterial injury: radiologic diagnosis and management. Radiology 1987; 165:709-14. 2. Kalangos A, Walder B, Faidutti B. Ruptured lumbar artery pseudoaneurysm: a diagnostic dilemma in retroperitoneal hemorrhage after abdominal trauma. J Trauma 1998;45:829-32. 3. Hulnick DH, Naidich DP, Balthazar EJ, Megibow AJ, Bosniak MA. Lumbar artery pseudoaneurysm: CT demonstration. J Comput Assist Tomogr 1984;8:570-2. 4. Haydu P, Chang J, Knox G, Nealon TF. Transcatheter arterial embolization of a traumatic lumbar artery false aneurysm. Surgery 1978;84:288-91. 5. Ikubo A, Komura M, Matoba N, et al. Lumbar artery pseudoaneurysm: an unusual cause of a retroperitoneal hematoma—report of a case. Surg Today 1993;23:635-8. 6. Peters M, Henny CP, ten Cate JW, Marsman JW, Breederveld C. Lumbar arterial rupture secondary to iliopsoas hemorrhage in a hemophiliac patient. Acta Haematol 1984;71:128-9. 7. Wall B, Keller FS, Spalding DM, Reif MC. Massive hemorrhage from a lumbar artery following percutaneous renal biopsy. Am J Kidney Dis 1986;7:250-3. 8. Kim KT, Kim BS, Park YH, Cho KJ, Shinn KS, Bahk YW. Embolic control of lumbar artery hemorrhage complicating percutaneous renal biopsy with a 3-F coaxial catheter system: case report. Cardiovasc Intervent Radiol 1991;14:175-8. 9. Kornberg E. Lumbar artery aneurysm with acute aortic occlusion resulting from chiropractic manipulation: a case report. Surgery 1988;103:122-4. 10. Marty B, Sanchez LA, Wain RA, et al. Endovascular treatment of a ruptured lumbar artery aneurysm: case report and review of the literature. Ann Vasc Surg 1998;12:379-83. 11. Rich NM, Hobson RW, Collins GJ. Traumatic arteriovenous fistulas and false aneurysms: a review of 558 lesions. Surgery 1975;78:817-28. 12. Bole PV, Munda R, Purdy RT, et al. Traumatic pseudoaneurysms: a review of 32 cases. J Trauma 1976;16:63-70. 13. Tveten L. Spinal cord vascularity. Extraspinal sources of spinal cord arteries in man. Acta Radiol Diagn 1976;17:1-6. 14. Ratcliffe JF. The anatomy of the fourth and fifth lumbar arteries in humans: an arteriographic study in one hundred live subjects. J Anat 1982;135:753-61. 15. Dumitru D, Zwarts MJ. Lumbosacral plexopathies and proximal mononeuropathies. In: Dumitru D, Amato AA, Zwarts MJ, editors. Electrodiagnostic medicine. 2nd ed. Philadelphia: Hanley & Belfus; 2002. p 861-2. 16. Ingersoll GL. Abdominal pathology in spinal cord injured persons. J Neurosurg Nurs 1985;17:343-8. 17. Bar-On Z, Ohry A. The acute abdomen in spinal cord injury individuals. Paraplegia 1995;33:704-6.
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