Table 1

Baseline characteristics of the study patients*

Exercise therapy group (n=55)Control group (n=54)
Age (years)58.4±10.057.2±9.8
Female sex, no. (%)31 (56.4)28 (51.9)
Body mass index (kg/m2)24.6±3.224.9±3.8
Minimum joint space in target joint† (mm)2.1±1.01.9±1.1
Pain duration (months)47.3±53.349.5±50.9
Harris Hip Score‡79.6±7.776.9±8.2
Bilateral radiographic hip OA, no. (%)38 (69.1)38 (70.3)
THR in contralateral hip at inclusion, no. (%)4 (7.3)2 (3.7)
Hereditary OA/known OA in family, no. (%)17 (33.3)21 (38.9)
>12 years of education, no. (%)43 (78.2)35 (67.3)
Work status
 Employed, no. (%)35 (63.6)36 (66.7)
 Sick leave, no. (%)8 (14.5)5 (9.3)
 Retired, no. (%)12 (21.8)9 (16.7)
WOMAC score§
 Pain subscale26.0±16.127.3±17.9
 Stiffness subscale34.8±23.734.3±20.5
 Physical function subscale21.1±15.323.6±15.7
  • *Plus-minus values are mean±SD. The body mass index is the weight in kilograms divided by the square of the height in metres.

  • †The minimum joint space in the hip joint was assessed according to Danielsson's criterion.15 For patients older than 70 years, a minimum joint space below 3 mm was characterised as radiographic hip OA. For patients younger than 70 years, a minimum joint space below 4 mm was characterised as radiographic hip OA.

  • ‡The Harris Hip Score is a clinician-administered tool to evaluate hip pain, hip function and hip range of motion.16 An overall score is calculated ranging from 0 to 100, with a lower score indicating more severe disease.

  • §The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) comprise three subscales (pain, stiffness and physical function) composed of 24 questions. Scores range from 0 to 100, with a higher score indicating more severe disease.19

  • OA, osteoarthritis; THR, total hip replacement.