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Understanding Giannis Antetokounmpo’s Knee Capsule Sprain

Led by Giannis Antetokounmpo, the Milwaukee Bucks have been the NBA’s top team for the majority of the 2019-20 season. However, the Bucks will be forced to traverse the immediate future without Antetokounmpo after the reigning MVP suffered a knee injury. The injury occurred during his matchup with LeBron James and the Los Angeles Lakers when he awkwardly landed following a dunk attempt. Subsequent testing was performed the following day. According to a recent press release, the MRI revealed Antetokounmpo suffered a “minor joint capsule sprain” that is expected to keep him out at least two games.

Joint capsule injuries have occurred in the NBA before and have been previously discussed on InStreetClothes.com when Jimmy Butler and Rudy Gay each suffered comparable injuries.

The joint capsule of the knee is a complex covering that surrounds the knee joint. It includes the patella, both menisci, multiple bursa sacs, and the assorted stabilizing ligaments of the knee. The joint capsule is involved in both active and passive stabilization of the knee while playing a key role in motion. The capsule is divided into two layers, the outer fibrous layer compromised of connective tissue and the synovial membrane.

The majority of capsule injuries involve the lateral or outer portion of the knee. This area is particularly complex and includes the iliotibial tract (IT band), lateral meniscus, as well as multiple tendons and ligaments. One of these tendons belongs to the popliteus, a muscle active in unlocking the knee and rotating the lower leg. Unfortunately, by allowing the popliteus tendon to enter at this point, the lateral capsule sacrifices a bit of its integrity and can be susceptible to injury. Multiple players including Gay, Jerryd Bayless, and Shaquille O’Neal have suffered injuries to this area.

Isolated capsule injuries are relatively uncommon. Most noted cases in the NBA have involved additional injuries like lateral collateral ligament (LCL) sprains or bone-related issues. These cases generally require significant time off. However, Gay’s absence due to his isolated joint capsule sprain lasted just one game. This could be an encouraging precedent for Antetokounmpo and the Bucks as the team described the injury as “minor” and did not mention any other involved structures. The Bucks medical team will continue to monitor the injury and plan on providing an update on Giannis’ status prior to the team’s game against the Celtics on March 12.

For now it appears as though Antetokounmpo avoided a significant injury. Nevertheless, the team’s positioning in the standings could allow the Bucks to take a conservative approach with his recovery and it wouldn’t be shocking to see Giannis miss additional time to ensure his long-term health and readiness for the postseason.