Table 1 Site, surgeon, participant and care characteristics

Site & surgeon characteristics

Sites

Public

10 (54%)

Private

9 (46%)

Number surgeons

118

Number participants

Per surgeon [(Median (IQR))

58 (31, 101)

Per site (Median (IQR))

70 (42.5, 127)

Length of stay (days)

Median (IQR)

5 (1.22, 1.95)

Participant characteristics

Joint (all surgeries)

Hip

801 (43.6%)

Knee

1037 (56.4%)

Bilateral joint arthroplasty

91 5.0%)

Public hospital

Yes

841 (45.8%)

Duration of surgery (hours)

(N = 1837)

Median (IQR)

1.6 (1.2, 1.0)

Length of stay (s = days)

Median (IQR)

5.0(4.0, 7.0)

Age (years)

Median (IQR)

67.6 (61.0, 73.9)

Sex

Female

1001 (54.5%)

Insurance status

Public

801 (43.6%)

Private health insurance

965 (52.5%)

Self-funded (private)

29 (1.6%)

Other insurance / compensation

16 (0.9%)

Department of Veterans Affairs

27 (1.5%)

Post-school education status (N = 1866)

Up to school completion

874 (45.5%)

Post school qualification

958 (54.5%)

BMI

Median (IQR)

29.7 (26.3, 34.2)

Current smoker (N = 1828)

Yes

150 (8.2%)

Comorbid conditions

Heart disease

459 (25.0%)

History stroke

111 (6.0%)

Bleeding disorder

19 (1.0%)

Previous VTE (N = 1873)

146 (8.0%)

Diabetes

298 (16.2%)

Hypertension

1118 (60.8%)

High cholesterol

685 (37.3%)

Kidney disease

56 (3.0%)

Liver disease

46 (2.7%)

Current cancer (any type)

37 (2.0%)

History of any type of cancer (N = 1873)

214 (11.7%)

Respiratory disease

333 (18.1%)

Anxiety or depression

342 (18.6%)

Mental health disorder

22 (1.2%)

Gastro-intestinal Reflux Disorder (GORD)

473 (25.7%)

Sleep apnoea

129 (7.0%)

Neurological conditions

51 (2.8%)

Any other musculoskeletal condition (N = 1873)

886 (48.2%)

Any other comorbid conditions not yet specified

712 (38.7%)

Previous total joint arthroplasty

Hip

238 (12.9%)

Knee

301 (16.4%)

Medications taken for Osteoarthritis*

Any

1438 (78.3%)

Paracetamol

1064 (57.9%)

Non-steroidal anti-inflammatories (NSAIDS)

511 (27.8%)

Opioids

378 (20.6%)

Antidepressant / antiepileptics, e.g. amitriptyline

35 (1.9%)

Steroids

5 (0.3%)

Any indications or contraindication for antibiotics

249 (13.7%)

History of antibiotic resistant infection or swab

MRSA

83 (4.5%)

Gram negative infection

1 (0.05%)

Self-reported allergy to penicillin, cephalosporin or all beta-lactam Abs

220 (12.0%)

Hospital admission with LOS > 5 days within three months of THA or TKA

13 (0.7%)

American Association Anaesthetists (ASA) score (N = 1798)

1 or 2

1225 (68.1%)

3 or 4

573 (31.9%)

Acute processes of care

Routine doppler performed (N = 1847)

146 (8.0%)

Cement fixation used (N = 1837)

1178 (64.1%)

Antibiotic cement

1117 (61.0%)

Tranexamic acid used (N = 1831)

1105 (60.3%)

Neuraxial anaesthesia (N = 1837)

1163 (63.3%)

Intra-articular Drain (N = 18)

803 (43.8%)

Tourniquet (only used for TKA)

886 (48.2%)

Blood transfusion (N = 1831)

326 (17.8%)

Indwelling catheter

1435 (78.1%)

Antibiotic prophylaxis

Cephazolin

1668 (90.8%)

Flucloxacillin

82 (4.5%)

Vancomycin

133 (7.2%)

Other cephalosporins (excluding cephazolin)

236 (12.8%)

Mechanical prophylaxis

SCD, calf compressors / foot pumps (N = 1810)

1657 (90.2%)

Graduated compression stockings (GCS) (N = 1835)

1385 (76.5%)

Wore any mechanical prophylaxis device (SCD/GCS)

1811 (98.5%)

Duration of any mechanical prophylaxis (days) (N = 1809)

Median (IQR)

27 (15,38)

Mobilisation post-surgery

First mobilised day 0 or 1

1368 (74.8%)

Low molecular weight heparins (LMWH)

13 (0.7%)

1446 (78.7%)

Aspirin (N = 1836)

458 (24.9%)

861 (46.8%)

Warfarin

66 (3.6%)

75 (4.1%)

Rivaroxaban

13 (0.7%)

158 (86.6%)

Dabigatran etexilate

9 (0.5%)

11 (0.6%)

Unfractionated heparin

4 (0.2%)

73 (4.0%)

Apixaban

2 (0.1%)

10 (0.54%)

Duration of VTE chemical prophylaxis (days)(N = 1831)

Median (IQR)

22 (12, 36)