Extension Assist KITS
The Certified Extension Assist Kits can be fit/retrofit to virtually any off the shelf Knee Orthoses or Knee Joints, or utilized in Custom Knee Orthoses and KAFO’s. The Extension Assist Kits offer a unique system providing significant extension assist at the knee joint. Kits are offered with the extension assist components only to be utilized with any knee joint, or with Certified’s Polycentric Knee Joints. Tension is adjusted/set by length of the tubing or with optional Extension Assist Ratchet that can be purchased as an accessory to provide easy assist/resist tension adjustment.
Extension Assist Kit Standard

CRK-700
Extension Assist Kit w/Polycentric Joints

CRK-710
Features, Benefits, & Options:
- Utilize/Incorporate with off the shelf knee orthoses, knee joints, or in custom Knee Orthoses and KAFO’s.
- Provides Significant Extension Assist at Knee Joint
- Strength of extension assist can be varied by simply adjusting the length of the tubing, or through utilizing the optional ratchet buckle to adjust tension
- Midsection channel allows complete tension relief for
sitting, or progression through the therapy/rehab process - Kit Includes all Extension Assist Components as shown
Features, Benefits, & Options:
- Provides Significant Extension Assist at Knee Joint
- High quality, low profile polycentric knee joints
- Strength of extension assist can be varied by simply adjusting the length of the tubing, or through utilizing the optional ratchet buckle to adjust tension
- Midsection channel allows complete tension relief for sitting, or progression through the therapy/rehab process
- Kit Includes all Extension Assist Components and Certified’s Polycentric Knee Joints as shown
Optional Extension Assist Adjustable Tension Ratchet Buckle

CRK-7RB
- Strength of extension assist can be varied by simply adjusting the tension on the tubing through the ratchet buckle as shown
Certified offers a Pre-Sized and Custom Extension Assist Knee Orthosis.
Certified offers full custom adult and pediatric fabrication services for the Extension Assist Kits, please see the Custom Orhotics section for more information.
Extension Assist Kit Ordering Information
Extension Assist Kits
Product# |
Description |
Unit |
---|---|---|
CRK-700 |
Extension Assist Kit Standard |
Kit |
CRK-710 |
Extension Assist Kit with Polycentric Knee Joints |
Kit |
CRK-7RB |
Extension Assist Adjustable Tension Ratchet Buckle |
Ea. |
Extension Assist Kit Individual Units
Product# |
Description |
Unit |
---|---|---|
CRK-4347 |
Extension Assist Tension Relief Midsection |
Each |
CKJ-2435 |
Certified Polycentric Knee Joint |
Pair |
CRK-7RB |
Extension Assist Adjustable Tension Ratchet Buckle |
Each |
CRK-4340 |
Extension Assist Condyle Pad |
Each |
CRK-4350 |
Extension Assist Tubing |
Foot |
CRK-4352 |
Extension Assist Tubing Attachments |
Each |
CRK-4354 |
Zip Tie |
Each |