Improper performance of a lumbar CT myelogram

by Olga Maystruk, Designer and Brand Strategist, and 
Karen Werth, Senior Risk Management Representative
 

Presentation

On March 1, a 55-year-old man consulted Neurosurgeon A about low back pain extending to the left buttock, hip, inguinal area, and anterior thigh just above the knee. The pain worsened with walking. The patient also experienced numbness to the lateral calf of the left leg and to the bilateral toe. 

The patient had a long, extensive history of procedures: lumbar laminectomy at L4-5; lumbar fusion at L2-3; and multiple epidural steroid injections of the lumbar spine. His history also included a 30-year diagnosis of polymyalgia; hypothyroidism; hypertension; depression; and anxiety. His medications included prednisone for polymyalgia rheumatica.

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Physician action

Neurosurgeon A ordered an MRI of the patient’s spine, which showed notable L3-4 and L4-5 stenosis with prominent disc extrusion on the left at L3-4. A CT scan revealed remote lumbar surgeries and degenerative changes. 

One month after the visit, Neurosurgeon A performed an L3-4 laminectomy and fusion. However, the disc was not removed.

Three weeks after the procedure, the patient experienced sudden left leg pain and numbness while walking. An MRI revealed a seroma in the operative site. The L3-4 disc was also noted as being more prominent than before the surgery. Neurosurgeon A ordered a CT myelogram with contrast.

On May 20, Radiologist A performed the myelogram procedure by injecting the site with an anesthetic; placing a 25-gauge high-flow pencil point spinal needle at the right oblique L1-2 level; advancing it into the spinal canal; injecting the contrast; and taking fluoroscopic images. 

The dye appeared to opacify the thecal sac and the flow exhibited no resistance. Shortly before completion of the injection of 10 cc of contrast, the patient reported intense pain in his right leg and was rolling on the table. Radiologist A stopped the injection immediately and took a spot fluoroscopy image.

The image showed contrast in the conus at the L1 vertebral level. Some contrast in the conus medullaris extended cephalad toward T12 in a decreasing irregular cone shape. Radiologist A calculated that there was 0.825 cc of contrast present in the conus. 

The new CT revealed a large recurrent disc herniation at L3-4 with extruded disc fragment extending inferiorly behind the left L4 vertebral body with severe impingement on the left lateral recess at the takeoff of the left L4 nerve root with vacuum disc changes seen within this extruded disc fragment as well as vacuum disc changes within the disc space itself. 

There was marked loss of disc height at the L4-5 level with 3 mm diffuse disc bulge and facet joint changes somewhat asymmetric to the left with moderate to severe canal stenosis of 5 mm and moderate to severe left L4 neural foraminal stenosis. There were severe L5-S1 degenerative disc changes with disc level osteophytes prominent laterally, with associated facet joint degeneration resulting in severe left L5 neural foraminal stenosis and moderate to severe right L5 neural foraminal stenosis. At the L1-2 level, there was a moderate canal stenosis of 6 mm secondary to 4 mm diffuse disc bulge, degenerative facet joint changes, and ligamentum flavum hypertrophy with minimal retrolisthesis. At the T12-L1 level, there was a mild to moderate canal stenosis of 8 mm secondary to a 3 mm diffuse disc bulge with degenerative facet joint changes, and ligamentum flavum hypertrophy. In addition, there was a possible 7 mm left lateral disc herniation with extruded disc fragment extending inferiorly behind the far left lateral L1 vertebral body.

The patient was admitted to a hospital where he exhibited lower leg pain, left-sided foot drop, significant back pain, and neurogenic urinary and bowel dysfunction. He was diagnosed with cauda equina syndrome. 

On June 1, the patient underwent an open bilateral posterolateral arthrodesis of L3-4 and L4-5, L3-4 laminotomy and discectomy, left L4-5 hemilaminectomy for decompression of the nerve root, and posterior segmental instrumentation and fusion at L3-5.

After being discharged from the hospital, the patient participated in physical therapy. The strength in his hips and right lower leg improved; however, there was minimal improvement in his left leg. 

Since the procedure, the patient has a spinal cord dysfunction that causes him to need a wheelchair and assistance at home. He continues to remain under the care of a pain management specialist due to severe neuropathic pain. He is now considered disabled.

Allegations

A lawsuit was filed against Radiologist A, alleging improper puncture site for the myelogram.  The plaintiff also alleged that the radiologist pierced and injected contrast into the conus medullaris of the spinal cord during the procedure.
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Legal implications

Consulting radiologists were split on whether the standard of care was met during the myelogram procedure. Experts unsupportive of the radiologist’s actions noted deviation from reasonable treatment by insertion of the spinal needle at an unsafe level (T12-L1) and the resulting injury to the spinal cord. The consultants for the defense did note the patient’s extensive list of pre-existing conditions which complicated the procedure and its outcome. 

Disposition

The case was settled on behalf of Radiologist A.
 

More on improper performance.
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