Solitary Calcified Nodules as the Cause of Carpal Tunnel Syndrome: Two Case Reports and Literature Reviews

Abstract

Solitary calcified nodule-related carpal tunnel syndrome (CTS) is rare and easy to be misdiagnosed owing to the high incidence of primary CTS. Release of the transverse carpal ligament without removal of the mass leads to persistence of the symptoms and subsequent complications like wasting of the thenar muscles. Here, we report two cases of solitary calcified nodule-related CTS and discuss the role of ultrasound in preventing misdiagnosis. Both patients reported persistent numbness over the lateral side of their palm and weakness of the right wrist with thenar muscle atrophy. One patient had undergone transverse carpal ligament release 2 years previously, and the other had received a local injection of lidocaine at the clinic. Neither patient experienced symptom relief. X-ray revealed a similar finding of nodule lesions in front of the capitate–hamate region. Solitary calcified nodule-related CTS was diagnosed, and the patients underwent nodule removal with/without transverse ligament release. The first patient was a typical case of misdiagnosed solitary calcified nodule-related CTS. The second patient had a definitive clinical sonographic diagnosis before surgery. The accurate diagnosis of secondary CTS is paramount for performing effective surgery. Thus, ultrasonography is an easy, convenient, safe, and effective method in screening for secondary CTS.

Ultrasound Findings in Less Frequent Causes of Carpal Tunnel Syndrome

“…Solitary calcified nodules are calcific masses located inside the CT that induce a mass effect on the MN with resultant CTS. 5,[49][50][51] The exact origin of these calcium deposits is unknown. Although solitary calcified nodules are often revealed on standard radiographs, US can accurately compare the relationship of the nodules with the MN as well as assess for associated neural changes (Figure 8).…”

“…Although solitary calcified nodules are often revealed on standard radiographs, US can accurately compare the relationship of the nodules with the MN as well as assess for associated neural changes (Figure 8). 50 Urate and Calcium Pyrophosphate Deposition Disease Tophaceous gout 3,52-54 and calcium pyrophosphate deposition disease (CPPD) 55 can present as masses inside the CT and cause CTS. The US appearance of a tophus is heterogeneous and can appear as a hypoechoic, hyperechoic, or mixed echogenic mass often surrounded by a hypoechoic halo.…”

“…Solitary calcified nodules are calcific masses located inside the CT that induce a mass effect on the MN with resultant CTS 5,49‐51 . The exact origin of these calcium deposits is unknown.…”

“…Although solitary calcified nodules are often revealed on standard radiographs, US can accurately compare the relationship of the nodules with the MN as well as assess for associated neural changes (Figure 8). 50 …”

Rare Tumors Causing Median Nerve Compression in Adults—A Narrative Review

“…Chronic trauma, rheumatoid arthritis, menopause, pregnancy, hypothyroidism, diabetes mellitus, acromegaly, and amyloidosis are also associated with the development of CTS. 1,2 Median nerve compression due to a benign or malign tumor is rare. A lipofibromatous hamartoma (LFH) is the most common histological type of tumor, but also lipomas, ganglion cysts, and fibromas are rarely found in the trajectory of the median nerve.…”