Jamaal Charles’ potential ACL tear headlines Week 5 NFL injury report

Yesterday's NFL action featured a relatively short list of key injuries. There was, however, a devastating one for fans of the Kansas City Chiefs, what appears to be a serious injury to Jamaal Charles' right knee. SB Nation Medical Expert Dr. Ali Mohamadi offers some insight into the Week 5 injury situation in his Monday morning injury update.

With the Chiefs driving to extend their lead midway through the third quarter, Charles took a handoff. After making a cut at the line of scrimmage, he buckled, a dreaded non-contact injury to his right knee. According to head coach Andy Reid, preliminary tests were suspicious for an anterior cruciate ligament (ACL) tear. The extent of the injury will be revealed following an MRI scheduled for Monday. If indeed Charles has torn his ACL, he would undergo surgery and lose the rest of his 2015 campaign.

The knee is a hinge joint between the femur (thighbone) and tibia (shinbone), with ligaments running along the sides and front to connect the bones. The ACL and posterior cruciate ligament (PCL) run along the front and rear of the knee, respectively, with the medial collateral ligament (MCL) spanning the inside and the lateral collateral ligament (LCL) spanning the outside. An injury to any of these ligaments can cause instability of the joint, but the ACL is of paramount importance.

ACL injuries most frequently take place without any physical contact being made to the knee (a non-contact injury). When it takes place, the signs tend not to be subtle: athletes sometimes describe a "popping" sound or sensation, followed by severe pain, swelling and difficulty bearing weight on the affected leg. A complete tear typically requires six to nine months of recovery following surgery, and that depends on whether other structures were involved.

Of note, Charles suffered a left ACL tear in Week 2 of 2011, underwent surgery and returned to his old form the next season. If he has indeed torn the right ACL this time, there is no reason to believe he won't have a similar outcome in 2016.

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Giants WR Odell Beckham suffered a hamstring injury following a touchdown reception in the third quarter of New York's thrilling victory over San Francisco. After sitting out a series he returned for his team's final, game-winning drive. While it is a positive sign that he was able to take the field again after the injury, it bears noting that the second-year receiver missed the first four games of his rookie campaign due to a hamstring strain, which are notoriously slow to heal and even more notorious for being prone to re-injury if tested before an athlete has fully recovered.

Don't be surprised if Beckham is limited in practice this week -- perhaps as much a precautionary measure as anything else -- prior to the Giants' matchup with Philadelphia next Monday night.

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It was a worrisome sight for Broncos fans yesterday when LB DeMarcus Ware was carted off the field in the first half of Denver's win at Oakland. It was later announced as a back injury. Following the game, Ware said his back "locked up" on him when he had a misstep on the Oakland Coliseum turf.

Early signs are positive for a speedy recovery. From his description, Ware will undergo further tests this week to confirm whether the injury was a muscle spasm or similar type of strain, which sounds likely given his description. If that's the case, it would require rest and possibly anti-inflammatory medications to help relieve any pain or discomfort that are likely to follow in the coming days.