Goniometry: Knee Flexion

Original Editor - Claire Knott Top Contributors - Nupur Smit Shah, Claire Knott, Lucinda hampton, Ruchi Desai, Vidya Acharya and Jess Bell

Introduction

Goniometer

The knee joint's range of motion (ROM) is an important clinical parameter used in knee assessment. Knee flexion can be measured with a goniometer. The goniometer can simply measure the joint angles. It has some limitations not allowing the clinician to analyse the ROM and track the knee joint during eg walking or maximum squat. Motion capture devices are mainly used to analyse the patient's gait and assess the condition of the joints and bones.

Anatomical Movement

Knee flexion

Axis and Plane for Motion

• Frontal axis

• Sagittal plane

Testing position

Subject in supine, with the knee in extension. Hip at 0° of extension, abduction, and adduction. A towel roll should be kept under the ankle to allow the knee to extend as much as possible.

Stabilization

Stabilize the femur to prevent rotation, abduction and adduction

Goniometer Placement

LOCATION OF AXIS/FULCRUM	STATIONARY ARM	MOVEMENT ARM
lateral epicondyle of the femur	along the femur to the greater trochanter	along the fibula to lateral malleolus

Technique

Passive ROM: The therapist holds the ankle in one hand and the posterior thigh in the other hand. Move the patient's thigh to 90° of hip flexion and flex the knee, bringing the heel towards the buttocks.

Active ROM: The therapist instructs the patient to bend the knee and pull the heel towards the buttock as much as possible.

Expected Findings

Expected range of motion in prone is 135 degrees

Functional Range Of Motion for Knee Flexion

Minimum requirement of knee flexion for activities of daily living is 90 degrees. 67 degrees is necessary in swing phase, 83 degrees is necessary in stair climbing, 90 degrees in descending stairs and 93 degrees while rising from a chair.