Table 1 Backward English translation of Arabic Version of the Oxford Knee Score (OKS-Ar)

1. During the past four weeks …… How will you describe the pain your knee often have?

  □ None

  □ Very little

  □ Little

  □ Moderate

  □ Severe

2. During the past four weeks ….. Do you have any problems in washing or drying your entire body because of your knee pain?

  □ None at all

  □ Very little difficulty

  □ Moderate difficulty

  □ Severe difficulty

  □ Hard to do this

3. During the past four weeks …….. Do you have any problems in the entry and exit of your car or when using public transport because of your knee ?(Whichever is used)

  □ None at all

  □ Very little difficulty

  □ Moderate difficulty

  □ Severe difficulty

  □ Hard to do this

4. During the past four weeks … How long you can be able to walk before it becomes severe knee pain? (With or without a stick)

  □ No pain (For more than 30 min)

  □ No pain (for 16–30 min)

  □ No pain (for 5–15 min)

  □ No pain (Just around house only)

  □ There is no time at all without pain/severe pain when walking

5. During the past four weeks … After sitting on the table to eat, how much was the pain that you feel when getting up from the chair because of your knee?

  □ There is no pain at all

  □ Little Pain

  □ Moderate Pain

  □ Severe Pain

  □ Worst pain

6. During the past four weeks … Do you feel stumbling when walking because of your knee?

  □ Rarely/Never

  □ Sometimes, or just at the beginning

  □ Often, not only at the beginning

  □ Most of the time

  □ All times

7. During the past four weeks … Are you able to kneel down and after that getup from the kneel down position?

  □ Yes, easily

  □ Little difficulty

  □ Moderate difficulty

  □ Severe difficulty

  □ No, it is impossible to do so

8. During the past four weeks … Do you suffer from pain in your knee in bed during the night?

  □ No nights

  □ A night or two nights only

  □ Some nights

  □ Most nights

  □ Every night

9. During the past four weeks … How much was the amount of the impact of knee pain on your usual work (including housework)?

  □ No impact

  □ Little impact

  □ Moderate impact

  □ Considerable impact

  □ Total impact

10. During the past four weeks … Have you ever felt that perhaps your knees are unstable or may make you fall?

  □ Rarely/Never

  □ Sometimes, or just at the beginning

  □ Often, not only at the beginning

  □ Most of the time

  □ All times

11. During the past four weeks… Is it possible for you to do shopping for yourself?

  □ Yes, easily

  □ Little difficulty

  □ Difficulty Medium

  □ With great difficulty

  □ No, it is impossible to do so

12. During the past four weeks … Is it possible for you to descend the one step of stairs?

  □ Yes, easily

  □ Little difficulty

  □ Moderate Difficulty

  □ Severe Difficulty

  □ No, it is impossible to do so