Multilevel calcium pyrophosphate dihydrate deposition in cervical ligamentum flavum: clinical characteristics and imaging features

Yueh-Hsiu Lu,Shih-Tien Wang,Po-Hsin Chou,Ming-Chau Chang,Hsi-Hsien Lin,Hsuan-Ying Chen,Chien-Lin Liu

doi:10.1186/s12891-021-04812-6

Abstract

BackgroundInvolvement in cervical ligamentum flavum is a rare manifestation of the calcium pyrophosphate dihydrate deposition disease. Only few cases of this condition have been reported. We revealed eighteen cases of CPPD in cervical ligamentum flavum that diagnosed at a single medical center. In our case series, clinical characteristics and magnetic resonance imaging findings of patients are described.MethodsWe retrospectively reviewed the medical charts and imaging studies of the eighteen patients with pseudogout attack of the cervical ligamentum flavum. In addition, we discussed the differences between this disease and ossification of ligamentum flavum in image manifestations.ResultsThere were fourteen men and four women aged between 59 and 87 years. Diabetes mellitus and hypertension were the most common comorbidities. Myelopathy and neck pain were presented in most patients. C4–5 and C5–6 were attacked most frequently, and multiple- rather than single-level involvement could be observed in our series. “Acute on chronic phenomenon” was a specific magnetic resonance image finding in patients whose symptom durations were between 2 to 5 months. Compared to ossification of ligamentum flavum, calcium pyrophosphate dihydrate crystal deposition had different image signs, including morphology, side of the involved ligament, no continuity with the lamina, acute on chronic phenomenon, and presence of retro-odontoid mass.ConclusionsNodular calcifications in cervical ligamentum flavum raise highly suspicion for calcium pyrophosphate dihydrate deposition and must be diagnosed by histological examination and polarized light microscopy. This disease is different from ossification of ligamentum flavum, and it could be recognized by specific image features.

Highlights

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, known as pseudogout, was first described by Zinan and Sitaj in 1958 [1]
In the presented case series, we report 18 patients with calcification of cervical ligamentum flavum who required surgical treatment and were confirmed to suffer from CPPD deposition disease by pathologic diagnosis
Compared with previous reports which discussed the findings of pathophysiology, laboratory tests, clinical manifestation, computed tomography (CT) scan, and various pathological studies, our report showed magnetic resonance imaging (MRI) findings and other clinical characteristics

Summary

Introduction

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, known as pseudogout, was first described by Zinan and Sitaj in 1958 [1]. In the presented case series, we report 18 patients with calcification of cervical ligamentum flavum who required surgical treatment and were confirmed to suffer from CPPD deposition disease by pathologic diagnosis. Compared with previous reports which discussed the findings of pathophysiology, laboratory tests, clinical manifestation, computed tomography (CT) scan, and various pathological studies, our report showed magnetic resonance imaging (MRI) findings and other clinical characteristics. Involvement in cervical ligamentum flavum is a rare manifestation of the calcium pyrophosphate dihy‐ drate deposition disease. Clinical characteristics and magnetic resonance imaging findings of patients are described

Methods

Results

Discussion

Conclusion