Fietsen ROM Flex Crank Shortener

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After knee surgery, cycle without resistance can help with a speedy recovery. This is equally true for recovering from ligament surgery or a new knee prosthetic. The ROM-Flex fits on all home trainers and on every bicycle.

Attaching the ROM Flex to your home trainer allows you to rehabilitate at home. With a minimum knee or prosthetic bend of 70 degrees, you can already make a complete pedal rotation. The ROM-Flex is adjusted to your affected leg.  On top of being able to rehabilitate at home, the ROM Flex also gives you mobility on the (bi)cycle. Should there be any permanent range of motion limitation, the ROM-Flex can be permanently installed on your (electric) cycle.

With the ROM-Flex you can quickly start on your recovery after an operation using your home trainer. This solution has adjustable settings, from 70 to 110 degrees bend.  The principle of the ROM-Flex is that the leg extension remains normal, while the required knee bend is significantly reduced to complete the pedal rotation. This video clearly shows how it works.

The reduced knee bend allows you to maintain the correct cycling position and ensures your joints are not over exerted. More importantly, you can enjoy cycling in a relaxed manner while working on your recovery.


ROM-Flex demo & installation (


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