Multiple Insufficiency Fractures Caused by Tumor-induced Osteomalacia:A Case Report
10.14193/jkfas.2025.29.4.177
- Author:
Youngkwan MOON
1
;
Youngrak CHOI
Author Information
1. Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Publication Type:Case Report
- From:Journal of Korean Foot and Ankle Society
2025;29(4):177-180
- CountryRepublic of Korea
- Language:English
-
Abstract:
Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by excess fibroblast growth factor-23 (FGF-23), leading to renal phosphate wasting, hypophosphatemia, osteomalacia, and multiple insufficiency fractures. TIO is often mistaken for stress fractures, osteoporotic fractures, and overuse injuries because of the nonspecific symptoms, such as bone pain, decreased muscle strength, and fatigue, leading to delayed diagnosis. This paper reports a patient with years of ankle pain in whom hypophosphatemia on a laboratory test led to the suspicion of TIO; the causative lesion was identified and excised, resulting in clinical improvement. Therefore, checking the serum phosphate level is essential in patients with recurrent, nonspecific, and multiple fractures. Hypophosphatemia is the most specific finding suggestive of TIO and, when present, should prompt an evaluation and treatment of the underlying lesion. Although uncommon, TIO can be recognized with basic blood tests, reducing diagnostic delay and improving patient outcomes.
