I said I wanted to hear from a doctor about Paul Pierce's knee.  

So I called one.

Surgeon Nick DiNubile is Orthopaedic Consultant to the Philadelphia 76ers, and an expert on sports injuries to knees.

Of course, he has not examined Paul Pierce's knee, so he can't make any real diagnosis.

But he did see the highlights of Pierce being dragged off the court in agony, and his gut reaction was: "He wasn't faking. I don't see any reason a player would fake that." 

So, what kind of injury might Paul Pierce be dealing with? Here are the clues Dr. DiNubile had to work with:

• Pierce has said he heard a pop at the time of the injury.
• Treatments have included Advil, ice, electronic stimulation, and laser therapy.
• He has not had an MRI.
• The team has said there was "no structural damage."
• Pierce has talked of swelling and stiffness.
• Pierce says he can walk and bend, but has sharp pain on the inside of his knee.
• Pierce says he does not have any history of knee problems.
• After being in excrutiating pain, Pierce returned to action quickly and appeared to be more or less fine.
  

Dr. DuNubile can hear those clues and make some educated guesses.

• Strained MCL ligament. The best-case scenario for Pierce, to explain sudden pain to the inside (medial side) of the knee is a minor sprain of the Medial Collateral Ligamentm (MCL). Such a sprain would normally keep a player out for a week or so, says Dr. DiNubile, but would likely heal of its own accord. 
• Meniscal tear. Another possibility, he says, is a small tear in the meniscus: "Not all meniscal tears require surgery. It's the NBA Finals, and the doctors and player might look at this differently than if it was a preseason game. This might be something that you play on now, but then when the season is over you stick a scope in there to clean it up."
• Partial ACL tear. A partial tear of the Anterior Cruciate Ligament (ACL) could fit these symptoms. "People sometimes think that if they hear a pop that means a torn ACL. But that's not strictly true," says Dr. DiNubile. "There are several things that can cause a pop. There's no way he came back and played with a torn ACL. But sometimes you can have just a little, partial tear of an ACL. That would worry me. If you have a partial tear, you are at high risk for a complete tear. When they say there is no structural damage to the knee, that's something that would be hard to say with certainty without conducting an MRI, which is why I would strongly recommend the MRI."
• Arthritis-related pain. Some mild arthritis in the knee, which is common among basketball players, can cause rough surfaces where a healthy knee would be smooth. "Years in the NBA are like dog years for knees," explains Dr. DiNubile. "A lot of players have some rough surfaces. A bit of that roughness can rub briefly in a way that would be very painful, but then subside such that you could return to action. Also, you can get a loose chip, which can float into a spot where it causes extraordinary pain for a short time, and then float off somewhere else and leave you able to play."

Three things that Dr. DiNubile finds worrying are the amount of pain Pierce was apparently in, reports of swelling, and the lack of a real diagnosis via MRI. He explains:

When we hear that there is swelling, it's important to figure out if there is fluid actually in the knee joint. If there is, then it's very hard to perform at 100%. You can play, but it will feel squishy and tentative. You'll be very aware of the knee.

The news that there is swelling is a strong indication that something really happened to that knee. 

If he didn't bump knees with someone else -- which can give you swelling on the surface but not really in the joint -- I'd assume the swelling is fluid in the joint, and that can be serious. If there's fluid in that knee, I'd think you'd really want an MRI to figure out what it is from, and then you might decide to drain some of the fluid, and examine it for clues, and possibly decide to inject something like novacaine to help cool it down.

You're going to have to make a decision, but the beauty of having this happen today, instead of in the old days, is that you can make an informed decision.

There's no reason not to get an MRI, unless he's just hell-bent on playing. In the Finals, you might take a risk of a bigger injury, because in the Finals it's a risk for a bigger prize.

One advantage they have with Paul Pierce is his game. He's not like Allen Iverson where he has to be all over the floor. They can get Pierce to certain spots on the floor and then he can shoot it.

But they're going to have to switch things around on defense. He can't be guarding Kobe Bryant all over the place. Swelling on the knee is like a blister. If you just leave it alone, it'll go away. But if you pound on it, it swells more.

(Photo by Jim Rogash/Getty Images)