The Buffalo Bills have a bit of a unique situation brewing at the offensive tackle position as they enter the 2016 offseason. To varying degrees, three players in which they've invested draft picks and development time have significant medical issues to explore.
Cordy Glenn is past his, actually, which is excellent news; the team awarded him the Ed Block Courage Award less after re-establishing himself as a quality starting left tackle despite having a kidney removed prior to the 2014 season. The kidney issue is now in the rearview mirror as the 26-year-old tackle, coming off of arguably his best season as a pro, hits free agency. The Bills have made it clear that they want to re-sign Glenn; given the state of the rest of his position, it might be downright imperative that they do so.
Seantrel Henderson, meanwhile, was reportedly diagnosed with Crohn's disease this year, and missed the final five games of the season as he was in and out of the hospital dealing with the symptoms. Per The Buffalo News, Henderson lost 20 pounds during the ordeal. It's an ailment that could affect Henderson for the rest of his playing career - it could be particularly difficult for him to keep weight on - and while there haven't been any indications that he won't return as the starting right tackle next summer, this should absolutely be in the back of the minds of the Bills' decision-makers as the roster is tweaked this spring.
One of the reasons that Cyrus Kouandjio fell to the second round of the 2014 NFL Draft (he was widely anticipated to be a first-round pick) was a chronic knee issue that teams were concerned about. At his year-end press conference on Monday, GM Doug Whaley confirmed that Kouandjio still has a "maintenance issue" with the same knee, which might explain why the Bills plucked Jordan Mills off of a practice squad and plugged him into the starting lineup at right tackle when Henderson went down rather than Kouandjio.
Mills, by the way, is a restricted free agent. That will make him easy enough to retain, but there's no guarantee that he'll be considered a concrete part of the team's future up front.
All four of those players played at least 200 snaps for the Bills this season, mostly due to Henderson's illness and unrelated minor injuries creating openings at right tackle. Buffalo still led the league in rushing, but quarterback Tyrod Taylor did have to deal with too much pressure at times. The Bills ran a successful offense in 2015 despite their revolving door at tackle, but to continue that progress in 2016, they'll need to make a lot of careful considerations about their current personnel.