Table 1.
Characteristics of the Frozen Shoulder Cohort, the General Population Comparison Cohort, and the Back Pain Comparison Cohort
| Frozen Shoulder Cohort | General Population Cohort | Back Pain Cohort | |
|---|---|---|---|
| No. of observations | 37,041 (100.0) | 370,410 (100.0) | 111.101 (100.0) |
| Sex | |||
| Male | 15,991 (43.2) | 159,910 (43.2) | 47,962 (43.2) |
| Female | 21,050 (56.8) | 210,500 (56.8) | 63,139 (56.8) |
| Age in years | |||
| 0–39 | 973 (0.3) | 317 (0.3) | |
| 40–59 | 25,311 (68.3) | 252,003 (68.0) | 75,580 (68.0) |
| 60–69 | 7,700 (20.8) | 77,070 (20.8) | 23,130 (20.8) |
| 70–79 | 2995 (8.1) | 29,959 (8.1) | 8983 (8.1) |
| 80 + | 1035 (2.8) | 10,405 (2.8) | 3091 (2.8) |
| Index year | |||
| 1995–2004 | 9403 (25.4) | 94,030 (25.4) | 28,196 (25.4) |
| 2005–2013 | 18,884 (51.0) | 188,840 (51.0) | 56,646 (51.0) |
| 2014–2016 | 8754 (23.6) | 87,540 (23.6) | 26,259 (23.6) |
| Type of hospital diagnosis of frozen shoulder | |||
| Primary diagnosis | 33,237 (89.7) | – | – |
| Secondary diagnosis | 3804 (10.3) | – | – |
| Inpatient | 2765 (7.5) | – | – |
| Outpatient | 34,173 (92.3) | – | – |
| Half day patient | 103 (0.3) | – | – |
| Comorbidities | |||
| Chronic obstructive pulmonary disease | 2368 (6.4) | 17,633 (4.8) | 10,953 (9.9) |
| Myocardial infarction | 1108 (3.0) | 7875 (2.1) | 3665 (3.3) |
| Stroke | 1481 (4.0) | 10,906 (2.9) | 5249 (4.7) |
| Thyroid disease | 1091 (2.9) | 7878 (2.1) | 3632 (3.3) |
| Shoulder trauma | 10,696 (28.9) | 17,076 (4.6) | 11,300 (10.2) |
| Shoulder surgery | 5794 (15.6) | 8935 (2.4) | 5747 (5.2) |
| Autoimmune disease | 4238 (11.4) | 28,803 (7.8) | 18,583 (16.7) |
| Dementia | 108 (0.3) | 1403 (0.4) | 697 (0.6) |
| Diabetes | 3987 (10.8) | 13,592 (3.7) | 6908 (6.2) |
| Congestive heart failure | 649 (1.8) | 4623 (1.2) | 2721 (2.4) |
| Peripheral vascular disease | 949 (2.6) | 6248 (1.7) | 4225 (3.8) |
| Cerebrovascular disease | 1752 (4.7) | 13,079 (3.5) | 6496 (5.8) |
| Ulcer disease | 880 (2.4) | 6141 (1.7) | 4439 (4.0) |
| Mild liver disease | 295 (0.8) | 3020 (0.8) | 1886 (1.7) |
| Hemiplegia | 75 (0.2) | 591 (0.2) | 384 (0.3) |
| Moderate to severe renal disease | 400 (1.1) | 2908 (0.8) | 1790 (1.6) |
| Any tumor | 2040 (5.5) | 18,629 (5.0) | 7057 (6.4) |
| Leukemia | 62 (0.2) | 432 (0.1) | 209 (0.2) |
| Lymphoma | 118 (0.3) | 1174 (0.3) | 719 (0.6) |
| Moderate to severe liver disease | 63 (0.2) | 657 (0.2) | 414 (0.4) |
| Metastatic solid tumor | 181 (0.5) | 1695 (0.5) | 1104 (1.0) |
| AIDS | 26 (0.1) | 337 (0.1) | 94 (0.1) |