Pablo Cikutovic

Introduction: The prevalence of ossification of the posterior longitudinal ligament (OPLL) has been primarily studied in East Asian countries; its prevalence in Western populations remains to be elucidated. We aimed to determine the prevalence of OPLL in a Chilean population aged 60 years and older using fluorine-18 fluorodeoxyglucose positron emission tomography and CT (PET-CT) as screening tool. Methods: We evaluated patients between 60 and 73 years consecutively studied with PET-CT in a University Hospital. We assessed whole-body CT scans in both sagittal and axial views to detect the presence of OPLL. We used the Mann-Whitney test to analyze continuous variables, the Fisher test for categorical variables, and a logistic regression analysis to determine the independent effect of age and sex on the presence of OPLL. Results: We studied 1,009 patients (median age = 66 years); 597 were males (59.17%). Nineteen patients had OPLL, with a prevalence of 1.88% (1.04 to 2.72). OPLL was more prevalent in men (2.68%) than in women (0.73%; P = 0.02). All cases presented cervical involvement; only one had cervical and thoracic OPLL. The median age of patients with OPLL (64 years) and without OPLL (66 years) was not statistically different ( P = 0.09). Male sex independently influenced the presence of OPLL (odds ratio = 3.85 [1.11 to 13.33]), age did not (odds ratio = 0.89 [0.78 to 1.02]). Discussion: This is the first study evaluating the prevalence of OPLL in Latin America. It shows a prevalence alike that in non-Asian populations in the United States and lower than the prevalence described in Asian populations.

Conventional radiography of hands has been the imaging technique used for the early diagnosis of rheumatoid arthritis, considering its easy access and ability to reveal structural damage. However, it does not provide information about inflammatory activity or prognosis of this disease. On the other hand, magnetic resonance imaging is becoming the technique of choice for the early diagnosis of this disease and for the assessment of treatment response. It has a better sensitivity for the detection of inflammatory findings that cannot be identified with physical examination, analytical and conventional imaging techniques. This article reports the imaging protocol for magnetic resonance of the hands used at our institution for the diagnosis and follow-up of patients with rheumatoid arthritis. We also review the main imaging findings of the disease.