Knee Traction Therapy for Osteoarthritis: Manual & Mechanical Physiotherapy Guide

Manual Traction for Knee Osteoarthritis: Evidence and Protocol

Knee osteoarthritis (OA) is characterized by progressive cartilage degradation, subchondral bone sclerosis, osteophyte formation, and synovial inflammation. In advanced OA, the joint space narrows — bringing bone surfaces closer together, compressing pain-sensitive structures, and impairing synovial fluid distribution to the remaining cartilage.

The Mechanism of Traction in Knee OA

When a physiotherapist applies manual traction to the knee — grasping the tibia and applying a gentle longitudinal pulling force — several therapeutic effects occur simultaneously:

1. Joint Distraction: The tibia separates slightly from the femur, temporarily increasing joint space
2. Synovial Fluid Redistribution: The negative pressure created draws synovial fluid into the joint, lubricating cartilage surfaces
3. Pain Gate Modulation: Large-diameter mechanoreceptors activated by the traction force inhibit pain signal transmission at the spinal cord level (Gate Control Theory)
4. Capsular Stretching: Gentle stretch of the posterior knee capsule reduces flexion contracture

Clinical Evidence

A 2021 systematic review in the Journal of Orthopaedic & Sports Physical Therapy found that manual joint traction combined with exercise therapy produced significantly better short-term pain and function outcomes than exercise alone for knee OA patients.

Physiotherapy Traction Protocol

Manual Traction Technique

Patient position: Supine with knee in 30° flexion (open-packed, most comfortable position for OA). Therapist grips the distal tibia with both hands. Apply a gentle sustained longitudinal distraction force for 30–60 seconds. 3–5 repetitions per session.

Mechanical Traction

A motorized traction unit with knee attachment applies computer-controlled distraction force (typically 10–15% of body weight) in intermittent 30-second hold / 10-second release cycles for 15–20 minutes.

Adjunct Therapies in the Same Session

• Patellar mobilization (glide medially/laterally and tilt)
• Infrared heat (10 minutes) before traction to warm joint
• TECAR or PEMF post-traction for anti-inflammatory effect
• Quad sets and straight-leg raises immediately post-traction