Limited knee Mobility - need to pedal an ellipse

[Gar]

Hi, I have had two full knee replacements, the right one has a limited bend no more than 85 degrees, since the last operation I have been unable to ride my bike. (although I have attempted to on several occasions and resulted in falling off) I believe there is a crank manufactured with an attachment that enables one to pedal in a elliptical arc instead of a circular one. Can anybody give me any guidance on sourcing a crank of this nature. Thank You; Gareth

[Graham]

I am not a user of such, but am aware of swing cranks from Highpath Engineering :
https://highpath.co.uk/

EDIT :
Be not afraid. This is not the Gar of old . . . . (probably) . . . .

[rualexander]

Also http://www.uni-cam.com/page/Home_Use%3A_Retroflex/

[thirdcrank]

There's an illustrated explanation of swing cranks here on the late Chris Bell's website

http://www.cornant.uk/eng/swingcrank.html

That link also points to Highpath to which Graham has already linked