March 18, 2005
Under The Knife
Barry Bonds' Knees
With apologies to Joe Mauer and Jason Kubel, the most famous knees this offseason belong to Barry Bonds. Yesterday's announcement that Bonds had undergone a second procedure on his right knee is the latest in a litany of health updates that have been flooding Bay Area papers and newscasts for the past six months.
Bonds suffers from chronic osteoarthritis. The cartilage in his knee joints is slowly wearing away, and the fibrocartilage tissue that evenly distributes weight inside the joint, known as the meniscus, is softening and becoming fragile. This type of degenerative joint disease usually affects individuals who are well into their 50s and 60s, but it is not unheard of for a younger person to have problems as severe as Bonds has. A genetic predisposition to osteoarthritis, or some sort of knee trauma, can lead to early onset.
Barry's recent knee problems were first addressed in 1999 when had a relatively simple operation on his right knee. Surgeons went in and debrided the damage that had developed in his cartilaginous tissues as a result of arthritis and wear and tear, and also performed a partial menisectomy to the medial meniscus. The doctors shaved down the tissue in places where it had become rough or unevenly worn, and removed the damaged patch of his torn mensicus. The surgery was a success, and Bonds had no problems more serious than typical arthritic achiness and swelling...at least until this off-season.
Last October 4, the day after the last game of the season, Bonds felt a "discomfort" in his left knee. After diagnostic testing and a visit with his knee specialist, Dr. Art Ting, Bonds underwent another "minor arthritis cleanup." This time he just had a debridement of damage to the tissue where it had become frayed. The surgery was a success and his off-season rehabilitation proceeded without complication.
At the end of January, Bonds felt pain in his right knee. After an MRI examination and consultation with his doctor, Bonds again elected to have surgery. In addition to the debriding and "cleanup" of the joint, this procedure also included another partial menisectomy of of the medial mensicus. At the time, Giants trainer Stan Conte said, "this was a minor cleanup procedure and in fact, the arthritis under Barry's knee cap was not as bad as we expected." It should be noted that this type of meniscus repair is entirely different than the menisectomy performed on Joe Mauer. Mauer's meniscus was so shredded that partial removal was impossible and the entire meniscus had to be excised. Mauer's knee is bone on bone at this point.
The surgery was a success; however, five days after the procedure, Bonds accidently bumped his knee against a table at SBC Park. The accident tore some of the sutures used to close the incision site and Bonds had to have the wound re-stitched. Rehabilitation began on schedule, and at times proceeded quicker than expected; Bonds began his outfield running and live batting practice before the team had planned for him to do so.
Two days ago, on March 16, Bonds returned to San Francisco for a checkup with his surgeon. It was originally reported that the checkup was scheduled as part of the normal course of rehabilitation, and not because of any concerns or setbacks. Rumors started flying when Conte spent the afternoon in an extended meeting with GM Brian Sabean, rather than updating the press on the outcome of the Bonds' visit. It now appears that an MRI examination performed by Dr. Ting showed new tears to both the medial and lateral menisci, for which Bonds went under the knife yesterday morning. The damage to the lateral meniscus was the more serious tear. It bears noting that even after multiple menisectomies Bonds still has an intact peripheral rim to his right medial meniscus. This is the important structure that prevents bone-on-bone contact, which would of course be incredibly serious for a major-league ballplayer.
How did Bonds develop the tears in the last month? It's hard to say; everyone on the Giants medical staff was surprised to hear the results of the MRI Wednesday. Osteoarthritis causes a substantial weakening of the menisci and it is not uncommon for older sufferers to tear their meniscus doing something as simple as bending down to pick up a dropped set of keys. Obviously Bonds' knees are not nearly so fragile, but there is really no way to tell whether the new tears were caused by that accidental table bump, some injury in his rehab, or simply by walking up a flight of stairs.
There is no reason to think that Bonds should have to miss more than a small part of the season. Conte has said that he expects Bonds to be "competitive" in six weeks, though it is imaginable that he would have to ease his way back into play with regular rest days. That schedule would put Bonds on pace to rejoin the team at the end of April. If Bonds missed even 20 games, the damage to the Giants would still be substantial. Using PECOTA's conservative prediction of Bonds' performance level for 2005 ("conservative" considering the last four years, not compared with every other baseball player in history), the Giants could expect to lose some 14 runs off their offensive potential. If he replicates last season's performance level, they could be down as much as 19 runs, or almost two wins.
Bonds no longer relies on a speed game so this knee problem should not cause any substantial degradation of performance in 2005. His defense will still be sketchy and for the sake of keeping his bat in the lineup it would be best that he not put his knee into any extraordinarily stressful situations. It is likely that Bonds will deal with some moderate swelling, stiffness, tenderness and discomfort, but it shouldn't be any worse than the arthritic pain that he has been suffering through for the last few years. As long as Bonds successfully rehabs his knee back to playing strength he should have no significant lingering problems. Remember that Bonds spent all of 2004 dealing with a serious case of painful back spasms, while producing one of the most prolific offensive seasons in baseball history.