Ac joint separation: will the bump cause any physical problems when doing sports?

Nope: As long as the clavicle is not dislocated posteriorly should be fine to participate in sports when healed.

Not likely.: As long as the injury is relatively minor, and once the ac separation has healed and matured, it is less likely that there will be any physical problems during sports. These injuries are usually very well tolerated. There are exceptions to this of course...Especially if the ac separation is severe (grade 3 or higher). In those situations, sometimes surgical correction is needed.

It shouldn't: Almost all these separations heal themselves, and leave a bump. You should be able to participate in all activities without discomfort, once fully healed.

AC SEPARATION: Typically an AC JOINT separation can be treated conservatively when it is only a type 2 or 3. Treatment consists of therapy to regain motion after a short period in a sling. If pain persists or you have pain with activities then sometimes surgical intervention is warranted. Consult an Orthopaedic surgeon for a complete work up. Hope this information is helpful. Take care. Wilsonshoulder.com