sorry to hear about this. it's hard to tell what's going on here without doing a physical examination. depending on the size of the wound that lump could be a normal part of the healing process. or it could be an infection or hematoma (collection of blood in the tissue). if your brother-in-law develops a fever over 101f (as measured by a thermometer not just by feeling a forehead or guessing) he should get checked out by a medical professional as this may be a sign of an infection developing. also if the wound continues to swell turns hot to the touch or oozes a green foul-smelling discharge those would all be reasons to head for urgent care. i'm wondering if your brother-in-law is up-to-date on his tetanus shot. every adult needs a booster injection every 10 years. if your brother-in-law doesn't know if his tetanus immunization is current he should be alert for symptoms of tetanus that could develop within 2 weeks of this accident including: headache trouble opening his mouth (lockjaw) trouble swallowing stiff neck back and shoulders again i'm sorry to hear about this accident. it's a good reminder to be careful using sharp objects and also for everyone to keep their tetanus shot current!
my brother in law accidentlty poked his hand with a jack knife. it bled and now he has a lump where he got poked.