key: cord-0700968-yal0ty0r
authors: Demyttenaere, Joachim; Martyn, Oisin; Delaney, Ruth
title: The Impact of the COVID-19 Pandemic on Frozen Shoulder Incidence Rates & Severity
date: 2022-02-12
journal: J Shoulder Elbow Surg
DOI: 10.1016/j.jse.2022.01.123
sha: e23ac061620232966895e62156538cbae3c325b5
doc_id: 700968
cord_uid: yal0ty0r

Background While there is evidence that the COVID-19 pandemic has profound physiological and psychological effects, there is no research aimed at understanding if the pandemic has had an impact on the incidence or severity of frozen shoulder (FS). The aim of this study is to compare the incidence and severity of idiopathic FS before and during the pandemic. Methods This is a retrospective cohort study to establish the incidence of FS during the pandemic, from March 2020 to January 2021 (pandemic study period), compared to the same time period one year earlier, before the pandemic (control group). All patients who were diagnosed with idiopathic FS were included. To assess the severity of the condition, Visual Analog Scale (VAS) for pain and Subjective Shoulder Value (SSV) upon presentation were recorded and the patients were categorized into 5 different treatment groups (0 injections, 1 injection, 2 injections, 3 injections or capsular release). As the pandemic and public health restrictions could have influenced the availability of appointments, the waiting time between referral and first appointment was calculated as a possible confounding factor. Statistical analysis was performed using the chi-square and student t-test for categorical and continuous variables respectively. Results There were 847 new patient consultations during the pandemic study period, of these 232 were for idiopathic FS. One year earlier, there were 898 initial consultations for a new shoulder problem, of these 176 were for idiopathic FS. This represents a relative increase of 39.8% (p<0.001) in the incidence of patients with FS. The mean SSV in the control group was 50 % ± 20 versus 45% ± 18 in the pandemic group, statistically significant (p=0.013) but unlikely to be clinically significant. The VAS pain scale was similar in both groups, mean 6 ± 2 and 7± 2, p = 0.06. There was no significant difference between the control group and pandemic group in the distribution of patients per treatment group (p=0.94). The mean waiting time from referral to appointment was not significantly different between the control and the pandemic group, 58 days ± 30 versus 55 days ± 27, p=0.30. Conclusion During the COVID-19 pandemic, there was a significant increase in the incidence of patients with FS. No significant difference in severity was observed. Further research is needed to evaluate a causal relationship between the COVID-19 pandemic and FS.

shoulder problem, of these 176 were for idiopathic FS. This represents a relative increase of 21 39.8% (p<0.001) in the incidence of patients with FS. The mean SSV in the control group was 22 50 % ± 20 versus 45% ± 18 in the pandemic group, statistically significant (p=0.013) but 23 unlikely to be clinically significant. The VAS pain scale was similar in both groups, mean 6 ± 24 2 and 7± 2, p = 0.06. There was no significant difference between the control group and 25 pandemic group in the distribution of patients per treatment group (p=0.94). The mean 26 waiting time from referral to appointment was not significantly different between the control 27 and the pandemic group, 58 days ± 30 versus 55 days ± 27, p=0.30. influenced the incidence and severity of idiopathic FS. Our hypothesis is that since the 62 beginning of the pandemic an increased number of patients are presenting with FS to our 63 single surgeon practice compared with prior to the pandemic.

This study was approved by our institution's Clinical Audit Committee.

All consultations by the senior author from March 2020 to January 2021, the pandemic period 68 and from March 2019 to January 2020, the control period, before the pandemic hit Ireland, 69 were manually reviewed in the electronic medical record. All patients aged 18 years or older, for FS such as diabetes were considered as primary frozen shoulders and frozen shoulders 76 with typical minor age-related degenerative changes such as non-traumatic partial thickness 77 rotator cuff tears, biceps degeneration, calcific tendonitis and minor radiological arthritis signs 78 were also included.

Exclusion criteria were secondary FS due to significant underlying primary pathology or structural damage (full thickness rotator cuff tears, fractures, dislocations) and patients with 81 FS with a first consultation outside the pre-defined time periods. All the patients in this single 82 surgeon practice were seen, examined and diagnosed with frozen shoulder by the senior 83 author.

Demographic data, risk factors and clinical characteristics were also recorded to assess for 85 homogeneity between both groups (age, gender, dominant side, manual work, diabetes, other 86 risk factors). weeks, if pain is persisting. In very painful cases this is supplemented with an oral course of 95 NSAID and/or a short, tapered course of an oral corticosteroid. In recalcitrant cases, an 96 arthroscopic circumferential capsular release is offered to the patient, followed by intensive 97 physiotherapy. As repeat injections and ultimately capsular release are reserved for cases with 98 persisting pain and/or stiffness, these treatments were recorded as a reflection of the severity 99 of the condition and of its responsiveness to treatment. The patients were categorized into 5 100 different treatment groups (0 injections, 1 injection, 2 injections, 3 injections or capsular release) where every "injection" stands for a set of injections into the subacromial and 102 glenohumeral spaces.

The pandemic and public health restrictions may also have influenced the incidence of other 104 shoulder pathologies, for example traumatic and sports injuries. It was possible that this could 105 have led to a falsely elevated incidence of FS. To assess this, the waiting time between 106 referral and first appointment was recorded as a possible confounding factor. Finally to 107 evaluate if due to the pandemic patients waited longer before seeking specialized care, the 108 duration from onset of symptoms to presentation was also determined.

As this was a retrospective review no immunologic data were available regarding COVID 110 infection or vaccination status.

Statistical analysis to assess for differences and associations between the two groups was 112 performed using the chi-square test for categorical variables and the student t-test for 113 continuous variables. Continuous variables are represented as a mean +-standard deviation. A 114 P-value < 0.05 was considered significant. The mean presenting SSV in the control group was 50% ± 20 versus 45% ± 18 in the 129 pandemic group, statistically significant (p=0.013) but unlikely to be clinically significant.

The VAS pain scale was similar in both groups, mean 6 ± 2 and 7± 2, p = 0.06. There was no 131 significant difference between the control group and pandemic group in the distribution of 132 patients per treatment group (p=0.94). The mean waiting time from referral to appointment was not significantly different between 135 the control and the pandemic group, 58 days ± 30 versus 55 days ± 27, p=0.30. At the time of 136 presentation to specialist care, there was no significant difference in the duration of the 137 symptoms between both groups, 258 days +-205 and 251 days ± 158, p=0.69.

The main finding of this retrospective cohort study is the significant increase in the incidence 141 of FS in the pandemic group. As the exact etiology and pathophysiology of FS remains 142 unclear it is not possible to give a definitive explanation for this association, however 143 identifying this association can help to a better understanding of the disease.

A state of low grade inflammation is probably an important factor predisposing to FS 11 . This 145 is commonly encountered in patients with DM, cardiovascular disease and thyroid disorders, 146 but is present in depression too 9 . It is a concern that the COVID-19 pandemic could have an traumatic injuries presenting to clinic, fear of presenting to clinics due to 197 temporary closures of public health services, travel restrictions, etc. While these factors can 198 affect the incidence of FS to some degree, it is very unlikely that a relative increase of 39.8% 199 could be attributed to this. The waiting time for an appointment between both groups was 200 similar, as well as the time since the onset of the symptoms, therefore logistical issues do not 201 explain the observed increased incidence of FS during the pandemic period. 1) Values are presented as a mean +-SD, n (%). 1) Values are presented as a number (%).

J o u r n a l P r e -p r o o f J o u r n a l P r e -p r o o f

Can 210 adhesive capsulitis of the shoulder be a consequence of COVID-19? Case series of 12 211 patients

Saudi Arabia Mental Health Surveillance System (MHSS): mental health 214 trends amid COVID-19 and comparison with pre-COVID-19 trends

The relationship between the 217 incidence of adhesive capsulitis and hemoglobin A1c

Post-vaccination frozen shoulder syndrome

Autoimmune and inflammatory diseases following COVID-19

The pathology of frozen shoulder

Musculoskeletal involvement of COVID-19: review of imaging

Treatment of Adhesive Capsulitis of the Shoulder

Onset of Frozen Shoulder Following Pneumococcal 257 and Influenza Vaccinations

Risk factors in 260 idiopathic adhesive capsulitis: a case control study