Skip to content

Range of motion

Hip, Knee, and Ankle ROM

Lower extremity ROM is transfer math. Rising from a chair takes roughly 90 to 110 degrees of knee flexion and about 85 degrees of hip flexion; stairs take more knee flexion plus ankle dorsiflexion. When a resident cannot clear a standard toilet or car seat, these numbers say why, and they justify the raised seat or cushion in the recommendation.

Normal values

Hip, normal values (AAOS)verify before clinical use
MotionDegrees
Flexion0-120
Extension0-20
Abduction0-40
Adduction0-20
Internal rotation0-45
External rotation0-45

Degrees from anatomical neutral. Confirm against the AAOS booklet or Norkin & White before clinical use.

Source: AAOS Joint Motion (1965)

Knee and ankle, normal values (AAOS)verify before clinical use
MotionDegrees
Knee flexion0-135
Knee extension0 (full extension)
Ankle dorsiflexion0-20
Ankle plantarflexion0-50

Degrees from anatomical neutral. Confirm against the AAOS booklet or Norkin & White before clinical use.

Source: AAOS Joint Motion (1965)

Clinical notes

  • Hip flexion norms matter double after hip replacement: the posterior-precaution limit of 90 degrees sits well below the normal 120, which is exactly why low chairs and standard toilets become hazards.
  • Measure hip extension prone or in Thomas test position; measuring supine lets the lumbar spine fake the motion.
  • Knee flexion of about 90 degrees clears most chairs; about 105 or more makes standard stairs comfortable; dressing tasks like donning socks want combined hip flexion and external rotation more than raw knee range.
  • Ankle dorsiflexion of about 10 degrees is the practical floor for normal gait and stairs; measure with the knee flexed and again extended to separate soleus from gastrocnemius tightness.

References

  1. American Academy of Orthopaedic Surgeons. Joint Motion: Method of Measuring and Recording. Chicago: AAOS; 1965. Values as commonly reproduced in goniometry references (e.g., Norkin & White, Measurement of Joint Motion).