No abstract

This study was undertaken to determine the contribution of various structures in the posterior cruciate ligament-deficient knee in resisting posterior tibial translation. With "isolated" injuries to the posterior cruciate ligament, the amount of posterior translation will decrease with the posterior drawer test as the knee is taken from neutral to internal tibial rotation. The present study was performed to conclusively determine the anatomic structure responsible for this clinical observation. The TestStar device was used to perform single-plane posterior drawer tests in 14 cadaveric knee specimens. The tests were performed with the knee in neutral tibial rotation and in 20 degrees of internal tibial rotation. The intact knee was tested and then the knee was tested after sequential sectioning of the meniscofemoral ligaments, the posterior cruciate ligament, the posteromedial capsule, and the superficial medial collateral ligament. With the knee in neutral rotation, posterior translation continued to increase as each structure was sectioned. With the knee in internal tibial rotation, posterior displacement was significantly less than in neutral rotation for each state until the superficial medial collateral ligament was sectioned; posterior translation was increased after its sectioning. Our data demonstrate that the superficial medial collateral ligament is the structure responsible for a decrease in posterior tibial translation in the posterior cruciate ligament-deficient knee.

No abstract

No abstract

We evaluated the effect of adjunctive healing measures on central tears of the adult goat medial meniscus and the role of magnetic resonance arthrography in the assessment of menisci that have undergone a repair. Peripheral tears were made unilaterally in the medial menisci of seven goats in Group I and repaired with nonabsorbable suture. Six Group II goats had central medial meniscal tears repaired as in Group I plus an exogenous fibrin clot. Eight Group III goats had central tears plus abrasion of the parameniscal synovium and tear edges. Six months after surgery, a magnetic resonance imaging scan and a magnetic resonance arthrogram were obtained and the menisci were examined grossly. Group I goats showed healing in all seven knees. Central tears repaired with a fibrin clot (Group II) showed healing in one of six knees (17%). Central tears repaired with abrasion (Group III) showed healing in seven of eight knees (87.5%). Magnetic resonance arthrography was 100% accurate in detecting the presence or absence of complete residual tears. This study supports the current trend of using adjunctive measures for repair of central tears. Furthermore, abrasion of the parameniscal synovium and the tear edges appears to be more effective than the use of an exogenous fibrin clot. Magnetic resonance arthrography is useful in the evaluation of menisci that have undergone repair.