Hyperparathyroidism¶

Definition¶

Hyperparathyroidism causes excessive parathyroid hormone (PTH) secretion, leading to increased osteoclastic bone resorption. In the spine, it produces osteopenia, subchondral resorption, brown tumors, and in secondary hyperparathyroidism (from renal disease), the characteristic "rugger jersey" spine.

Types¶

Primary — Parathyroid adenoma or hyperplasia; causes hypercalcemia with increased bone resorption
Secondary — Response to chronic hypocalcemia (chronic kidney disease); causes rugger jersey spine and osteosclerosis
Tertiary — Autonomous PTH secretion after prolonged secondary hyperparathyroidism

Spine Imaging Findings¶

Osteopenia — Generalized decreased bone density
Subchondral resorption — Erosion of the vertebral endplates
Brown tumors — Expansile lytic lesions containing hemorrhagic tissue and giant cells; rare in the spine
Rugger jersey spine — In secondary hyperparathyroidism (see Renal Osteodystrophy)
Compression fractures — From weakened bone

Clinical Pearl

Primary hyperparathyroidism produces diffuse osteopenia and subchondral resorption, while secondary hyperparathyroidism (renal) produces the rugger jersey spine with osteosclerosis. This distinction reflects the different pathophysiology — primary causes net bone loss, while secondary produces a mixture of resorption and reactive new bone formation.

Key Points¶

Primary hyperparathyroidism causes osteopenia and subchondral resorption
Secondary hyperparathyroidism causes rugger jersey spine and osteosclerosis
Brown tumors are expansile lytic lesions — rare in the spine
Compression fractures occur from weakened bone
Check serum calcium, phosphate, and PTH levels

References¶

Vilanilam GK, Nikpanah M, Vo CD, Kearns C. Osteitis Fibrosa Cystica: Brown Tumors of Hyperparathyroidism and End-Stage Renal Disease. RadioGraphics. 2023;43(5):e220211. https://pubmed.ncbi.nlm.nih.gov/37079460/
Chang CY, Rosenthal DI, Mitchell DM, Handa A, Kattapuram SV, Huang AJ. Imaging Findings of Metabolic Bone Disease. RadioGraphics. 2016;36(6):1871-1887. https://pubmed.ncbi.nlm.nih.gov/27726750/
Bennett J, Suliburk JW, Morón FE. Osseous Manifestations of Primary Hyperparathyroidism: Imaging Findings. Int J Endocrinol. 2020;2020:3146535. https://pmc.ncbi.nlm.nih.gov/articles/PMC7054819/
Wittenberg A. The rugger jersey spine sign. Radiology. 2004;230(2):491-492. https://pubmed.ncbi.nlm.nih.gov/14752190/
Helbing A, Leslie SW, Levine SN. Primary Hyperparathyroidism. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated 2026 Jan 31. https://www.ncbi.nlm.nih.gov/books/NBK441895/
Muppidi V, Meegada SR, Rehman A. Secondary Hyperparathyroidism. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated 2023 Aug 28. https://www.ncbi.nlm.nih.gov/books/NBK557822/
Rugger jersey spine (hyperparathyroidism). Radiopaedia.org. https://radiopaedia.org/articles/rugger-jersey-spine-hyperparathyroidism-1
Zander D, Bunch PM, Policeni B, et al. ACR Appropriateness Criteria® Parathyroid Adenoma. J Am Coll Radiol. 2021;18(11S):S406-S422. https://pubmed.ncbi.nlm.nih.gov/34794597/