Doctor Tells Us His Dire Warning For Christian McCaffrey After Latest Injury

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During the snowy December 1 NFL game between the Buffalo Bills and San Francisco 49ers, both teams tackled the elements as best they could. Buffalo, with the icy home advantage, skated away with a demanding 35-10 win over San Francisco. Usually a dominant team in the NFC West, the 49ers have been swamped with injuries all season, leading to consistent underperformance for the 2024-2025 season. One of the star players battling constant injuries is Christian McCaffrey, who left Sunday's game early due to a posterior cruciate ligament (PCL) injury impacting his right knee.

Kyle Shanahan, coach for the 49ers, told Fox News that McCaffrey could be out for a while. "I think PCL is usually a couple weeks, but I'm not exactly sure yet," he said. Fellow 49ers teammate Brock "Mr. Irrelevant" Purdy also bemoaned the loss to Fox, saying, "He's one of the best running backs in the league. When you lose him like that, I think it takes away just sort of how we do some things in the offense."

Medical expert Jason Singh, MD, spoke exclusively with Nicki Swift about the next steps for McCaffrey, and his advice is full of warning. As Chief Medical Officer at One Oak Medical, Singh recommends McCaffrey take rest and rehabilitation seriously, or else be at risk of losing more than just a season of play — he could lose his whole career.

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The transformation of Christian McCaffrey, who won Offensive Player of the Year in 2023, has included being pummeled by injuries for most of 2024. During the 49ers' November 10 matchup against the Tampa Bay Buccaneers, he struggled in his first appearance on the field after dealing with Achilles tendonitis in both his feet. Determined to have a good game and get back on track in Buffalo, McCaffrey posted 53 yards and seven carries before crushing his knee trying to make a touchdown. It was landing while his knee was still flexed that caused the PCL injury, and these injuries vary in how long rehabilitation will take.

According to physician Jason Singh, MD, "PCL injuries generally occur from direct trauma to the anterior tibia while the knee is flexed. We grade the severity to help determine its recovery." Meaning, depending on how severe the tear is to the ligament, the recovery time could be anywhere from four weeks to six months. On December 2, Niners coach Kyle Shanahan told ESPN that McCaffrey would be out for about six weeks but would thankfully not require surgery. However, according to Singh, if McCaffrey doesn't take these injuries seriously and fully recover, it could spell danger for the running back's future performance.

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As devastating as the loss of Christian McCaffrey is to the 49ers' potential success for the season, McCaffrey will need to take it easy to be able to get back into top shape for upcoming seasons. Dr. Jason Singh says, "You need the PCL for knee stability during deceleration and cutting movements which is essential for a running back's performance." This, coupled with the string of other injuries McCaffrey has suffered — Achilles tendinitis in both feet, a calf strain, and now the PCL tear — means if McCaffrey doesn't properly recover, he will be prone to more injuries in the future.

"Interestingly, his recent injury history suggests a concerning pattern of lower extremity issues ... These injuries, while individually manageable, create a cumulative effect," Singh says. Like the old song goes, "head, shoulders, knees, and toes," everything is connected. And if McCaffrey doesn't fully treat each injury, it could mean his body might compensate in other ways, possibly spurring more problems down the line. Singh continues, "Rehabilitation is crucial and for him to maintain high-level performance, careful load management will be crucial." Hopefully this will give McCaffrey's fiancee Olivia Culpo plenty of time to care for him in the offseason.