Hypokalemia mimicking a herniated vertebral disc

• Published in: The spine journal Vol. 15; no. 6; pp. e53 - e56
• Main Authors: Delhey, Patrick Roman, MD, Holzapfel, Boris Michael, MD, Kanz, Karl-Georg, MD, Mayer-Wagner, Susanne, MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.06.2015
• Subjects: Adult; Back Pain - etiology; Diagnosis, Differential; Female; Herniated vertebral disc; Humans; Hypokalemia; Hypokalemia - complications; Hypokalemia - diagnosis; Intervertebral Disc Displacement - diagnosis; Life-threatening; Muscle weakness; Muscle Weakness - etiology; Neurologic Examination; Orthopedics; Herniated vertebral disc; Life-threatening; Hypokalemia; Muscle weakness
• ISSN: 1529-9430; 1878-1632
• DOI: 10.1016/j.spinee.2013.08.021

Abstract Background context A herniated vertebral disc is a common cause of paralysis. Other causes include infections, tumors, and neurologic diseases. A rare and dangerous but in most cases easily treatable cause is hypokalemia. Clinically, the acute symptoms may resemble a herniated vertebral disc, but hypokalemia per se is life-threatening by causing heart arrest through ventricular tachycardia or fibrillation. Purpose A patient with back pain and neurologic deficit in the lower extremities after a history of a herniated vertebral disc presented, who finally receives the diagnosis of hypokalemia. Study design Case report. Methods A 25-year-old female patient presenting after a fall with muscle weakness in both legs was followed clinically and radiographically. Results Neurological examination showed a lower extremity muscle weakness with three-fifths muscular strength of the quadriceps and tibialis anterior muscle on both sides. Reflexes were diminished bilaterally, anal sphincter tone was normal. Plain radiography suggested a posterior rim fracture of L5, but computed tomography did not confirm this diagnosis. The laboratory investigation revealed a hypokalemia of 1.7 mEq/L. On electrolyte replacement, the patient recovered immediately. Conclusion This report describes a misleading diagnostic case of back pain and neurologic deficit after a trauma and sensitizes for the possible life-threatening diagnosis hypokalemia, which is rare but easily treatable.