Nelson originally suffered his hamstring injury during practice leading up to Green Bay's Week 8 contest against the Jacksonville Jaguars. The official NFL injury report and official Packers blog tell the rest of the story:
- Week 8: out (hamstring)
- Week 9: out (hamstring)
- Week 10: bye
- Week 11: active (hamstring, probable)
- Week 12: active
- Week 13: active, left game after trying to play through pregame discomfort (hamstring)
- Week 14: out (hamstring)
- Week 15: out (hamstring)
- Week 16: out (hamstring), according to Packers beat writer Tyler Dunne
Hamstring injuries are infamous for lingering, and Nelson's case is no exception.
The term "hamstring" describes any of three muscles in the back of the thigh—the semimembranosus, semitendinosus and biceps femoris muscles—that serve to bend the knee. In other words, a player uses them during every single step he takes.
Unfortunately, hamstrings are also extremely fragile.
If a tackle forcefully straightens a bent knee, a hamstring strain occurs. Sprinting without warming up a cold, tight hamstring can also lead to injury.
A "hamstring strain" diagnosis implies one of three types of injuries. A grade-one strain occurs when an athlete over-stretches the muscle without it tearing. In a grade-two strain, the muscle partially tears, while a grade-three strain means a muscle has completely torn and may require surgery for repair.
Grade-one and grade-two strains heal on their own. However, they take time to do so, and during the healing process, the muscle is significantly weaker than normal and, as a result, more susceptible to injury.
In other words, attempting to return from a strain too soon can cause further injury, and that may be what occurred in Nelson's case.
Exact medical details are unavailable; however, some educated speculation suggests that Nelson's injury saga progressed as follows:
- Grade-two strain suffered during Week 8 practice, holding him out until Week 11
- Healing but weakened hamstring holds up through Week 12 game
- Nearly fully healed strain mildly re-injured during Week 13 warm-ups
- Attempt to play through re-injury results in significant further injury, holding Nelson out through Week 16 (so far)
The Packers should not be blamed for trying to get Nelson back out there.
No. 1 receiver Greg Jennings missed significant time this year due to midseason surgery, and while Randall Cobb and James Jones have filled in tremendously in his stead, the Green Bay offense does not look quite the same this season.
Nevertheless, the Packers (10-4) clinched the NFC North last week. Given the stellar performance of Cobb and Jones, Green Bay would be wise to make sure Nelson is absolutely, undoubtedly 100 percent healthy before he takes the field once again.
If they are not careful, the Packers run the risk of this injury nagging at Nelson throughout the remainder of the 2012 regular season and postseason alike.
However, if and when Nelson's hamstring does heal, he will represent yet another weapon for Aaron Rodgers' already loaded offense.
Hopefully for the Packers, that happens in time for the playoffs.
And if that is the case, watch out, NFC.
Dave Siebert is a medical/injury Featured Columnist for Bleacher Report who will graduate from medical school in June, 2013. He plans to specialize in both Family Medicine and Primary Care (non-operative) Sports Medicine, and injury information discussed above is based on his own knowledge.