# Vertebral Pain in Acute COVID-19--Cases Report
## 1 Introduction  
Novel coronavirus infections were first documented in December 2019 in Wuhan (China) and spread rapidly worldwide, leading to the declaration of a global pandemic by the World Health Organization on 11 March 2020 [1]. The infection has been diagnosed in 179,261,894 individuals, caused 3,884,666 deaths worldwide ([2], accessed on 23 June 2021), considerably affected all areas of everyday life, and caused large economic burdens.  
Various manifestations of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been increasingly presented in the literature [3; 4; 5]. First, respiratory tract infection with lung involvement and severe respiratory distress syndrome was described [3; 4; 5; 6]. As the pandemic spread, the diagnostic tools became widely available and the number of infected patients rose, with a wide variety of symptoms described.  
From the data now available, it is known that the virus can invade different tissues and infection can exhibit numerous symptoms [7]. Primarily the respiratory tract is infected (nasal congestion, sore throat, cough, shortness of breath) [7; 8]. The virus also has the ability to invade the neural system (headache, dizziness, cognitive disorders, various forms of psychic deterioration) [7; 8; 9; 10; 11], digestive tract (vomiting, diarrhea, abdominal pain) [5; 7; 8; 9; 10], cardiovascular system (chest pain, cardiac injury, thromboembolism) [8; 10; 12], musculoskeletal system (joint pain, myalgia) [7; 8; 9; 10; 12], and also other body organs [9; 10; 12] and cause different pain manifestations [7; 8; 10; 12; 13]. The fever accompanying the infection might not be presented in mild, oligosymptomatic, or asymptomatic cases [7; 8; 9; 12].  
Nevertheless, a majority of patients infected with SARS-CoV-2 are asymptomatic or have only mild symptoms [7,8,12]. Some of the symptoms are unusual or even bizarre--e.g., loss of taste and smell [7,8,14], burning pain of skin [15], chest pain not corresponding to the site of lung involvement [16], various skin lesions [17]. There are still many unknowns regarding the relationships or processes of symptom development and their predictive value for the severity and outcome of the course of this disease [6,9,18].  
Pain is a commonly present non-specific symptom of viral infections, SARS-CoV-2 infection included. Muscle aches and pain are experienced by 15-59% of patients with coronavirus disease 2019 (COVID-19, the disease caused by SARS-CoV-2) [7,8,12,13,19]. However, the precise, direct, and indirect mechanisms of tissue damage and pain genesis in COVID-19 are not known and are the subject of worldwide research [19,20]. The mechanism of COVID-19-induced pain remains unclear. Neuroinvasivity in human coronaviruses is known; the axonal transport is possibly used for propagation in neural involvement [11,14,21,22]. Pain occurs approximately 2 days before seeking medical attention [12,16] and is a more common sign (69.3%) [12] than loss of smell (43.5%) [12] and taste (33.9%) [14].  
Among symptoms associated with COVID-19, less attention has been paid to vertebral pain. Low back pain or neck pain could be presented as nonspecific constitutional symptoms with other symptoms such as headache, fatigue, sore throat, cough, etc. [7,12] or, based on our experience, also as the only or early sign in oligosymptomatic COVID-19.  
Here we describe the cases of four patients presenting with vertebral agic syndrome with/without radicular or pseudoradicular irradiation in later PCR-confirmed SARS-CoV-2 infection. We highlight the pressing need for vigilance in the examination of patients with new onset of back pain during the pandemic. On the basis of case reports, we sought to lessen the gap in currently available literature by adding another mosaic stone to the knowledge of COVID-19 manifestation and provide a helping hand to other colleagues in the first line.