The present study was a prospective, single-center cross-sectional analysis conducted on 128 PCR positive symptomatic patients who were followed up in our COVID-19 clinic between August 1st and November 30th 2020. There was no lockdown in the country at the time of our study.
Prior to the evaluation, patients were given verbal and written information on the nature of the study. Informed consent forms were signed upon admission to the study. All procedures were conducted according to the relevant principles of the Helsinki Declaration. The study was approved by the Ethics and Research Committee of the Ankara City Hospital (Protocol E1-20-1121). All patients enrolled in the study signed a consent form.
In accordance with the principles of the local committee, all PCR positive symptomatic patients were hospitalized until their tests showed negative and their symptoms had been resolved by the time of the study.
Inclusion criteria required that patients were aged between 18 and 65 years, not bedridden, cognitively intact, cooperative, not on a mechanical ventilator, and ambulatory with or without support.
Since back pain symptoms were extremely common among many COVID-19 patients prior to the study, we excluded any patients with a history of chronic back pain (more than 3 months), pre-diagnosed (clinical record review) cervical/thoracal disc herniation / spondylosis / osteoarthritis, scoliosis, kyphosis, being either bedridden or using a wheelchair, patients using a mechanical ventilator, dependent, unable to cooperate, with known progressive / non-progressive neurological disease, with previously diagnosed pulmonary disease, previous surgery and a trauma history of the lower extremities and vertebrae, as well as those with a history of malignancy and inflammatory disease.
All symptomatic patients who tested positive and hospitalized in a COVID-19 clinic were asked an open question about their acute symptoms on their first day in the clinic. Answers were only considered positive if the patient was currently experiencing the acute symptom.
The demographic characteristics of the patients including their age, gender, body mass index (BMI), presence of comorbidity, smoking status and occupation were all recorded. In addition, pre-illness activity levels were scored using the Nord-Trøndelag Health Study Physical Activity Level for Work (HUNT) (9).
The HUNT staging scale scores an individual’s physical activity level at work. According to this, patients were grouped according to their work status and physical activity level. The stages were defined as; Level 1: sedentary workers, Level 2: work involving walking but no heavy lifting, Level 3: work predominantly involving walking, Level 4: work involving heavy lifting and especially tasks requiring heavy physical activity.
The type of treatments used, the presence of pneumonia (all patients were screened with CT on the first day and repeated if necessary), whether oxygen was required at any time, and the pattern and stage of pneumonia findings in computerized chest tomography (CT) were all recorded during the hospitalization period.
As suggested by a partnership between the Radiological Society of North America, the Society of Thoracic Radiology and the American College of Radiology (10–12), the pneumonia pattern was grouped as negative, typical, indeterminate and atypical (10–11).
The 6-minute walking test (6MWT) was conducted with two cones placed 30 meters apart on a flat hard walking surface to assess the patients’ current aerobic capacity on the first or second day of hospitalization according to the work schedule. After the patient had had 2 trial walks and rested for 30 minutes, the longest distance he had covered was recorded in meters.
After all the patients had been questioned about their symptoms, the patients were divided into two groups as patients with and without back pain, and their demographic and disease characteristics were compared. In addition, we investigated whether back pain was related to these demographic and disease characteristics.
Demographic data and disease characteristics were collected by the same physician for all patients included in the study. 6MWT was applied by another physician and CT findings were evaluated by an infectious diseases specialist. All three physicians were blinded to group assignments and to all other patient information.
Statistical Analysis
All statistical analyses were carried out using SPSS 20.0 for windows statistical package. The variables were investigated using Kolmogorov‑Smirnov test to assess whether or not they were normally distributed. Descriptive statistics were demonstrated as mean ± standard deviation (SD) for continuous variables and as a percentage (%) for nominal variables. T test and 𝜒2 test were performed for any comparison between the groups. Pearson’s correlation test and univariate regression analysis were performed for the relationship between back pain and their demographic and disease characteristics. For statistical significant correlations, multivariate logistic regression analysis was used. A p value of < 0.05 was considered significant.