Understanding Jabari Parker’s ACL Injury and Where He Goes From Here

• Post By: Jeff Stotts
• Date: December 18, 2014
• Category: NBA, Understanding...

The Milwaukee Bucks had been one of the early surprises of the 2014-15 season and are already within two wins of matching last year’s total. However the excitement and promise took a hit Monday when rookie forward Jabari Parker tumbled to the floor after his left leg awkwardly buckled. The team initially ruled the injury a sprain and further testing confirmed the damage was extreme. The Bucks confirmed that Parker suffered a torn an anterior cruciate ligament (ACL) with others reporting a true “Unhappy Triad” injury. The so-called Triad includes damage to the anterior cruciate ligament (ACL), the medial collateral ligament (MCL), and the medial meniscus.

It’s official now — Jabari Parker sprained both the ACL and MCL. (Triad for those in the know.) Surgery, season over.

— Will Carroll (@injuryexpert) December 17, 2014

The ACL and MCL are two of the four primary stabilizing ligaments in the knee. These ligaments, along with the fibrocartilage discs known as the menisci, stabilize the knee joint and prevent excessive movement of the knee. They also work synergistically to absorb the various stress placed on and through the joint. However if the external force applied to the knee is excessive, the ligaments may be pushed beyond their yield point and tear or rupture. An injury to the MCL often includes medial meniscus damage, as fibers of the ligament are attached to the disc.

The extent of Parker’s injury will be determined during surgery. At that time, a repair or a removal will be performed to address any meniscus damage discovered. His season is over and he now begins a long and tedious recovery process.

The injury is a setback for the second overall pick but by no means a career-ending one. ACL tears are fairly common in the NBA as roughly four players a year have suffered the injury since the 2005-06 season, the year in which the NBA adopted the daily inactive list. Two players, Josh Howard and Michael Redd, have been unfortunate to suffer multiple ACL injuries. The average time of recovery from the date of an ACL tear to the individual’s return to professional basketball is 327 days (roughly 11 months). However that number includes the recoveries of Nerlens Noel and Derrick Rose, two ACL cases that were handled very conservatively. Quick recoveries have occurred including Denver forward JJ Hickson’s recent return that occured just 211 days (nearly 7 months) following his ligament tear. However these cases are the exceptions and not the rule.

There is a silver lining in Parker’s injury, as he should be available for the start of the 2015-16 season. Over the last nine seasons, 72 percent of players that tore their ACL prior to the All-Star break were back by the start of following season. Of the eight players that did not make it back, three had their returns delayed due to being free agents. Summer league seems unlikely but it’s very possible we see Parker on Opening Night of his sophomore season.

While the injury won’t end his career, it will likely stunt his growth. As ESPN Insider Kevin Pelton detailed following Derrick Rose’s ACL tear, it does appear that players can anticipate a dip in projected effectiveness on a per-minute basis in the season following ACL surgery. Looking further at the data, I discovered that 22 of the 30 players to suffer ACL injuries (excluding those that occurred in college like Noel and those players with multiple ACL tears) saw their Player Efficiency Rating (PER) regress in the first season following surgery. 14 of these players saw their PER rebound in the second season after surgery and 12 players would go on to have career highs in PER following surgery.

Like Pelton, my findings suggest age plays a major role. 12 of the cases I examined involved players that were 23 or younger at the time of the injury. Nine of these players went on to have their career-best PER in a season after their surgery. The four exceptions were Derrick Rose, Nenad Krstic, Adam Morrison and Robert Swift. Morrison and Swift were out of the league two years following their respective injuries and the jury is still out on Rose, who even healthy would have a hard time matching the PER of his MVP season. It should also be noted that these figures do not incorporate ACL injuries prior to 2005-06. As a result the success of players like Jamal Crawford and Al Harrington were not included.

Parker has a long, mentally grinding few months ahead of him. However history suggests he is more than likely to bounce back, even if it takes a few seasons to regain his traction. His youth should aid in his recovery and this injury could be nothing more than a minor setback in what should be a promising career.