If someone has a knee reconstruction is it possible for them to play sports that they did before?

Yes, but depends on. Final outcome of surgery will depend upon the degree and nature of the problem, and as determined by ortho. Ligament reconstruction 2-8 wks. Amount and intensity of weight bearing, returning to work, kind & intensity of activity/sports, may be few weeks. If cartilage gone, full recovery-never. May have to avoid spec sport, limit to low impact, change lifestyle. Follow-up with ortho will determine.

Related Questions

After a knee reconstruction on my ACL & meniscus. How long will it take for me to be able to play sports?

About 6 months. You should expect to get back to full activity around 6 months if all goes well. Many patients will take a year to fully recover.
8-9 months. Return to cutting sports after acl reconstruction is currently a controversial topic. It takes 7-8 months after reconstruction for a autograft (your own tendon) to reincorporate, and it takes 8-9 months after an allograft (donor tendon) to reincorporate. Retear rates after early return to sports is higher, so a conservative 8-9 months is recommended.