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Updated: Jun 20, 2026
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Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity
Published on: September 16, 2022
A metabolic cause of spinal deformity
Nora M Effelsberg1, Thomas Hügle, Ulrich A Walker
1Department of Rheumatology, Basel University, Burgfelderstr. 55, CH 4012 Basel, Switzerland.
Metabolism: Clinical and Experimental
|September 22, 2009
Summary
Alkaptonuria is a rare cause of chronic low back pain due to homogentisic acid (HGA) buildup. Early diagnosis and potential treatments like nitisinone show promise for managing this degenerative condition.
Area of Science:
- Biochemistry
- Genetics
- Orthopedics
Background:
- Alkaptonuria (ochronosis) is a rare inherited metabolic disorder.
- It results from mutations in the homogentisate 1,2-dioxygenase gene, affecting tyrosine metabolism.
- Characterized by the accumulation of homogentisic acid (HGA) in the body.
Observation:
- A 38-year-old male presented with a 6-year history of chronic low back pain.
- Clinical findings included limited spine mobility, narrowed disc spaces, and calcifications on radiographs.
- MRI revealed Modic type II changes indicative of chronic disc degeneration.
Findings:
- Massively elevated urinary excretion of homogentisic acid (HGA) confirmed alkaptonuria.
- HGA polymers deposit in connective tissues, leading to cartilage degeneration and ochronosis.
- This underlies the patient's chronic back pain and spinal degeneration.
Implications:
- Alkaptonuria is an uncommon but significant cause of chronic backache.
- Awareness among musculoskeletal clinicians is crucial for timely diagnosis.
- Emerging therapies, including nitisinone (an HGA formation inhibitor), are under investigation and show promising results for joint mobility.
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