49ers’ DE Nick Bosa is dealing with a groin strain, according to head coach Kyle Shanahan. The injury occurred at some point during San Francisco’s 37-15 win over the Panthers on Sunday.
Groin strains can be tricky to diagnose because we often see similar symptoms across a variety of causes. Adductor strains and osteitis pubis are the two most common causes of groin pain in football players, and are difficult to distinguish.
Osteitis pubis is a chronic injury that causes inflammation in the center of the pelvis, but it also affects the symphysis pubis (a small joint in between the left and right pelvis), adductor and abdominal muscles, and surrounding connective tissue. If misdiagnosed or mismanaged, osteitis pubis can last for the rest of someone’s life, causing severe damage.
In contrast, adductor strains (which are more common than osteitis pubis) are easily treatable and less severe long term. The adductors of the hip are the: adductor longus, magnus and brevis, gracilis, obturator externus, and pectineus. Together, these six muscles allow us to raise our knees to our midline, and provide stabilization when we walk or run.

Other common causes of groin pain include sports hernia, groin disruption, nerve compression, and snapping hip syndrome. In Bosa’s case, it’s safest to assume it’s an adductor strain, but there is the potential there for something much more serious.
Shanahan said the team will reevaluate Bosa ahead of Wednesday’s practice to get a better idea of where he’s at. Groin strains don’t heal overnight, and Bosa has a history of muscular strains in his legs, so he could miss a week or two if it is mild. In the case it is more severe, he could miss up to six weeks.