Current Concepts in Joint Replacement (CCJR)
BY JOHN CHOPACK, JUNE 7, 2004
Current Concepts in Joint Replacement (CCJR) is the best conference for hip, knee and shoulder reconstruction. The meeting allows for surgeons to present new data, debate topics and demonstrate new techniques via live surgery. Our major take-away is that surgeons will never agree on one product or technique. This leaves room for many players and many investment opportunities. More specifically, the conference also demonstrated that veteran surgeons can be set in their ways and reluctant to change products or techniques within the large joint reconstruction sector.
Many new and old topics were presented and debated including fixation techniques, alternate bearings and MIS solutions for hips, knees and shoulder procedures.
Here were some topics we found most interesting:
Unicompartmental knee procedures
The major take-away was that unicompartmental knee prosthesis had a place in the orthopedic marketplace. Attending surgeons debated about the number of patients to qualify for such a product as well as who should be performing the procedures. Some believe that the lack of good instrumentation and visibility makes the procedure extremely difficult for the typical surgeon; only the most qualified knee surgeons should be performing the procedure, while others disagree. It was agreed upon that 5-10% of patients suffering from arthritis of the knee are candidates for a unicompartmental prosthesis.
UniSpacer
The prosthesis and procedure had no support among members of the faculty. Surgeons cited that metal on cartilage articulations have had poor clinical results regardless of the location of the prosthesis. Others pointed out that the prosthesis is worse than the first generation interpositional spacer, the McKeever/Macintosh. When asked what he thought of the 'UniSpacer,' Dr. Bob Booth commented that he tried to 'think' about it as little as possible and that a colleague of his performed 16 of them and had to revise 13 at a very early stage.
Cross-linked Polyethylene
Faculty members were able to agree that cross-linked pollyethylene was certainly applicable for hip articulation. However, surgeons disagree on the use of the product as a tibial insert. Some site that under high contact stresses the highly cross-linked poly has a tendency for massive failure via cracking and delamination propagation.
Cartilage Repair - Osteochondral Defects
Surgeons pointed out the benefits of allograft osteochondral defects but stated the outcomes really depended on how fresh the grafts were. Dr. Allen Gross pointed out that the best outcomes were with a graft which was 72 hrs old or less and from a patient who was less than 30 years old. This indicates that there is significant variability in allograft products.
Live Surgeries
Several surgeons performed live surgeries, observed by the physicians in attendance. We were able to view both Dr. Aaron Hoffman's Quad-Sparing MIS Knee Replacement utilizing Ortho-SOFT's Surgical Navigation as well as Dr. Douglas Dennis's Knee Replacement using a DePuy Sigma Posterior Stabilized Mobile Bearing Knee.
It was our first opportunity to see in detail how surgeons utilize surgical navigation during an operating room setting. Dr. Hoffman did a great job of pointing out how his 'eye-balling' ability differed from the actual readings of the software. If an elite surgeon like Dr. Hoffman has trouble eye-balling angles for implanting orthopedic devices, one can only imagine how well a less astute surgeon may estimate degrees of rotation and varus/valgus deformities.
