Myles Jack Injury: Updates on NFL Prospect's Recovery from Knee Surgery

As the 2016 NFL draft approaches, former UCLA Bruins linebacker and once-projected first-round pick Myles Jack is recovering from knee surgery.
Continue for updates.
Jack to Avoid Microfracture Surgery
Friday, April 29
ESPN's Adam Schefter reported Dr. James Andrews told Jack he won't need microfracture surgery.
Jack Says He'll Be Ready for Rookie Camp
Thursday, April 28
Jack "insists" he won't need surgery on his knee and will be available for rookie minicamp, according to Dave Birkett of the Detroit Free Press.
Teams Reportedly Want Jack to Sign Injury Waiver
Wednesday, April 27
Tony Pauline of DraftInsider.net reported teams are considering asking Jack to sign an injury waiver prior to drafting him.
Jack Reportedly Off Giants' Big Board Due to Injury Concerns
Wednesday, April 27
The New York Giants have removed Jack from consideration for the 10th overall pick, according to Jordan Raanan of NJ.com.
Details of Jack's Knee Condition Revealed
Tuesday, April 26
Albert Breer of NFL Network, citing sources, reported on Sunday that Jack has a "chondral defect in his right knee," adding that it's "up for debate" how much of a problem it will be for him.
Stanford Health Care explained what a chondral defect is:
A chondral defect refers to a focal area of damage to the articular cartilage (the cartilage that lines the end of the bones). An osteochondral defect refers to a focal area of damage that involves both the cartilage and a piece of underlying bone. These can occur from an acute traumatic injury to the knee or an underlying disorder of the bone.
This is distinctly different than arthritis and should be thought of differently as the treatments are significantly different as well. Unfortunately, an isolated cartilage defect, without any underlying bone attached to the fragment, is not commonly repairable. The cartilage is often not viable when it is separated from the bone and therefore must be removed which can be done with an arthroscopic procedure. However, the now exposed bone should be treated, if possible, to attempt to stimulate growth of new cartilage. Some healthy flaps of cartilage can be repaired by special techniques.
Ian Rapoport provided additional insight into the severity of Jack's injury Tuesday on NFL.com:
The repair of the lateral meniscus that tore off the bone when he suffered the injury in September is not the issue, according to several sources with direct knowledge of Jack's situation. Instead, the cartilage and bone have begun to separate, creating what is referred to by medical professionals as an osteochondral defect.
If or when the bone and cartilage fully separate, Jack will need to undergo another procedure and it will keep him out for a prolonged period of time.
Breer also noted that the defect "may or may not be a result of his September injury. He can play with it. Whether it'll affect career length is the question." Regardless of the severity of the ailment, Breer noted that teams outside the top 10 in the draft are doing "more background on [Jack]" because he may fall down the draft board.
Jack to Be Picked in Top 15
Monday, April 25
Bleacher Report's Jason Cole reported that Jack is still expected to be selected within the first half of the first round despite questions about his knee:
Cowboys Reportedly Worried About Jack's Knee
Sunday, April 24
Charles Robinson of Yahoo Sports reported the Dallas Cowboys flagged Jack's knee and put him onto their "sub board" after the linebacker's medical update.
Video of Jack's Workout Emerges
Monday, April 18
John Thornton, Jack's agent, shared video of his client going through drills:
Long-Term Stability of Jack's Knee Reportedly a Worry
Monday, April 18
Les Bowen of the Philadelphia Daily News spoke to an NFL source who called Jack's knee a "time bomb," adding that it could give him "several good years or not." Bowen's source told him that there is "bone and cartilage starting to break away."
Latest Updates on Jack's Recovery
Friday, April 15
Rapoport reported that teams had "differing opinions" on Jack's status following Friday's medical recheck. "The teams that believe in Myles Jack likely won't be deterred by today's medicals," Rapoport said. "Others view his knee as a potential issue."
Dane Brugler of CBS Sports confirmed the concerns by many teams, adding there are "long-term question marks."
Jack Discusses Medical Recheck
Friday, April 15
Jack told Stephania Bell of ESPN that his medical recheck went great. "No one had any concerns," Jack said.
Jack Sets Visits with NFL Teams
Friday, April 8
Cole reported that Jack will visit the San Francisco 49ers this weekend after recent visits with the Atlanta Falcons and Baltimore Ravens.
Jack Wasn't 100 Percent at Pro Day
Friday, April 8
Matt Miller of Bleacher Report reported, per a source, that Jack was 85 percent at his pro day and is currently working on accelerating and decelerating.
Miller reported on March 15 that Jack had a 40-inch vertical jump and is "about 80 [percent] working back from [his] meniscus injury."
Jack's Agent Posts Video of LB Doing Agility Drills
Wednesday, March 30
Jack Won't Have Personal Pro Day
Tuesday, March 29
Jack, who was expected to have a personal pro day on April 1, will no longer hold the event and is unlikely to run the 40-yard dash prior to the NFL draft, per Michael Silver of NFL Network.
On March 15, Rob Rang of CBS reported Jack, who did not participate in shuttles or the 40-yard dash at UCLA's pro day, was expected to participate in the events at his personal pro day.
Jack Meets with Surgeon
Thursday, March 10
Rapoport reported Jack will ramp up training after being "fully cleared by the UCLA surgeon."
On Feb. 26, Jack said he felt "100 percent" going into the meeting ahead of his pro day on March 15, per Chase Goodbread of NFL Network.
Jack Wasn't Cleared for Combine
Tuesday, Feb. 16
Jack told Josh Weinfuss of ESPN.com on Tuesday the only physical drill he would do is the bench press. He will also attend team interviews, meet with the press and undergo medical testing. Miller added Jack is "healthy" but "not ready" for a combine workout.
"Personally, I feel great," Jack said, per Weinfuss. "The knee, I can do whatever I can do with the knee, running, cutting. It feels great. It feels like a new knee."
Jack Top Defensive Talent Despite Injury
Jack, 20, tore his lateral meniscus during a practice session on Sept. 22. The injury limited him to only three games in a junior campaign that was widely expected to establish him as perhaps the best defensive player in the 2016 class.
As it stands, Jack is still widely expected to be a high-first-round pick despite the injury. ESPN.com's Todd McShay has him going No. 17 to the Atlanta Falcons in his most recent mock draft, while CBS Sports has him as the fourth-ranked prospect overall.
Jack has maintained the injury hasn't affected his athleticism, which was strong enough that he played running back in spurts at UCLA.
"I feel stronger, faster, I've gotten a lot of work in," Jack told Weinfuss. "Just working combine drills and stuff like that...drops, working pass rush and everything. I've been working on all that."
If Jack winds up proving himself healthy before the draft, it's not out of the question that he'll leap back into the fringes of top-five consideration.
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