Reconstruction of the anterior cruciate ligament: association of graft choice with increased risk of early revision.

We examined the association of graft type with the risk of early revision of primary anterior cruciate ligament reconstruction (ACLR) in a community-based sample. A retrospective analysis of a cohort of 9817 ACLRs recorded in an ACLR Registry was performed. Patients were included if they underwent primary ACLR with bone-patellar tendon-bone autograft, hamstring tendon autograft or allograft tissue. Aseptic failure was the main endpoint of the study. After adjusting for age, gender, ethnicity, and body mass index, allografts had a 3.02 times (95% confidence interval (CI) 1.93 to 4.72) higher risk of aseptic revision than bone-patellar tendon-bone autografts (p < 0.001). Hamstring tendon autografts had a 1.82 times (95% CI 1.10 to 3.00) higher risk of revision compared with bone-patellar tendon-bone autografts (p = 0.019). For each year increase in age, the risk of revision decreased by 7% (95% CI 5 to 9). In gender-specific analyses a 2.26 times (95% CI 1.15 to 4.44) increased risk of hamstring tendon autograft revision in females was observed compared with bone-patellar tendon-bone autograft. We conclude that allograft tissue, hamstring tendon autografts, and younger age may all increase the risk of early revision surgery after ACLR.

Anterior cruciate ligament graft rotation. Reproduction of normal graft rotation.

The purpose of this study was to determine normal rotation of the anterior cruciate ligament and to provide a technique for reproduction of this rotation. Ten fresh-frozen knees were dissected of all soft tissue except for the anterior cruciate ligament. Specimens were secured in a vise in 60 degrees of flexion. Each tibia was allowed to spin freely on the femur, and rotation was recorded. Anterior cruciate ligament reconstructions, using bone-patellar tendon-bone grafts, were then performed on all specimens using four graft rotations. Each specimen was then tested to assess how the graft twist affected tibial rotation. The average tibial rotation of the normal anterior cruciate ligaments was 55 degrees internally. Previous descriptions of anterior cruciate ligament reconstructions have advocated medial or internal rotation of the graft to reproduce normal anatomic rotation of the anterior cruciate ligament. Our cadaveric dissections have demonstrated that the anterior cruciate ligament normally produces internal rotation of the tibia in relation to the femur. Reproduction of this anatomic rotation is accomplished with 90 degrees of lateral rotation of the tibial plug toward the fibula.

Windshield-wiper loosening: a complication of in situ screw fixation of slipped capital femoral epiphysis.

A retrospective review of patients treated for slipped capital femoral epiphysis (SCFE) by in situ screw fixation with a cannulated titanium screw was performed. Of the 18 hips with at least 1-year follow-up, windshield-wiper loosening of the cannulated screw in the femoral head had occurred in three. In all three cases, the screw had been left protruding > 1.5 cm from the anterolateral cortex of the femur. We postulate that with hip motion the protruding screw is toggled by the anterolateral soft tissues, causing a windshield-wiper effect in the femoral head, leading to eventual screw loosening. We believe that leaving the screw protruding from the fascia lata is a potential source of screw loosening by the windshield-wiper mechanism and now routinely place the screw head within 1.5 cm of the anterolateral cortex of the femur.

Compartment syndrome. A complication of intravenous regional anesthesia in the reduction of lower leg shaft fractures.

Forty-one consecutive patients who had closed reduction of closed lower leg shaft fractures under an intravenous regional anesthetic are reviewed for the complication of compartment syndrome. Four patients were graded as having mild compartment syndrome, two as moderate, and five as severe, giving an overall rate of 27%. This was compared with a control group of 39 consecutive patients who also underwent closed reduction of closed lower leg shaft fractures, but under general anesthesia or intravenous analgesia alone rather than an intravenous regional anesthetic. In the control group, three patients were graded as having mild compartment syndrome, and two as severe, giving an overall complication rate of 13%. The authors feel that the use of the thigh tourniquet with the intravenous regional anesthetic technique increases the frequency of compartment syndrome as a complication in lower leg fractures.

Three-dimensional cinematographic analysis of water polo throwing in elite performers.

Thirteen members of the United States Men's Water Polo Team were filmed using two synchronized cameras while shooting at a goal. Three-dimensional (3D) coordinates of the throwers' shoulder, elbow, wrist, and the ball were used to estimate elbow angle, elbow angular velocity, and ball velocity at release. Ball release velocities ranged from 14.5 to 25.8 m/sec, with peak elbow angular velocities averaging 1137 degrees/sec. Peak elbow angular velocity typically was reached just prior (x = 28 msec) to release as the elbow approached full extension. Results are significant in establishing the efficacy of 3D techniques in evaluating throwing mechanics and may prove useful in: identifying characteristics of superior performers, assessing differences in throwing technique between injured and non-injured populations, and providing a kinematic data base for further studies of throwing kinetics and potential injury mechanisms.