Arthroscopic posterior cruciate ligament reconstruction.

Operative treatment of posterior cruciate ligament (PCL) injury is becoming more common as understanding of the natural history of the untreated PCL-deficient knee increases and the surgical techniques improve. The current recommendations for surgical reconstruction include patients with multiple ligament injuries and patients with isolated grade III PCL injuries. An understanding of the anatomy and biomechanics of the PCL is essential for successful reconstruction. This article presents a reproducible surgical technique for arthroscopically assisted PCL reconstruction.

Meniscal repair using the inside-to-outside technique.

The frequent occurrence of degenerative joint disease following complete or partial meniscectomy is well recognized. Meniscal repair has been shown to lead to a lower prevalence of degenerative changes in the knee. Arthroscopically assisted inside-to-outside meniscal repair is a safe, reproducible technique for for salvaging the torn meniscus.

Anterior cruciate ligament surgery 1996. State of the art?

During the past 20 years, numerous basic science and clinical studies have improved the treatment of the anterior cruciate ligament deficient knee. As our understanding of the short term and long term morbidity caused by the torn anterior cruciate ligament has improved, and the morbidity of surgical reconstruction has decreased, the indications for anterior cruciate ligament reconstruction have widened. Anatomic placement of the anterior cruciate ligament graft has improved the outcome of surgery, although various techniques are used to achieve that goal. The patellar tendon autograft has been established as the gold standard graft choice, but several graft choices are available, and have given similar results in early followup. One of the major advances in anterior cruciate ligament reconstruction has been the acceptance of early range of motion and controlled endurance and strength training during the postoperative period.

Uncommon causes of shoulder pain in the athlete.

Injuries to the shoulder are very common in athletes. In addition to common causes of shoulder pain in the athlete, such as instability, it is important to consider less common causes. Familiarity with these uncommon entities will lead to appropriate diagnosis and treatment in a timely fashion.

Cervical spinal stenosis and stingers in collegiate football players.

We evaluated the relationship of cervical spinal stenosis with the occurrence of "stingers" in collegiate football players who participated at our institution from 1987 through 1991. Preparticipation cervical spine radiographs of 266 players were used to measure Torg ratio. Forty players with stingers were identified: 34 had an extension-compression mechanism; 6 had a brachial plexus stretch mechanism. Time-loss neck injuries occurred in 31 players; the remaining 195 players were asymptomatic. The mean Torg ratio was significantly smaller for the stinger group (P = 0.02). The Torg ratio was less than 0.8 at 1 or more levels in 47.5% of the stinger group, 32.3% of the time-loss neck pain group, and 25.1% of the asymptomatic group. No player with a brachial plexus stretch mechanism had a mean Torg ratio less than 0.8, but 20.6% of the players with an extension-compression mechanism had a mean Torg ratio less than 0.8. Players with a Torg ratio less than 0.8 had 3 times the risk of incurring stingers. We conclude that cervical spinal stenosis increases the risk for having stingers with complicated clinical courses.

The outcome of Charnley total hip arthroplasty with cement after a minimum twenty-year follow-up. The results of one surgeon.

We evaluated the results of 330 total hip arthroplasties that were performed with use of the Charnley prosthesis and cement in 262 patients by the senior one of us between July 1970 and April 1972. All hips had been thoroughly assessed preoperatively to document the patient's functional level. All patients had been disabled because of pain in the hip or a fracture of the hip, and 212 patients (81 per cent) had used walking aids. At a minimum of twenty years after the index operation, eighty-three patients (ninety-eight hips) were still living, 174 patients (224 hips) had died, and five patients (eight hips) had been lost to follow-up. The outcome of the arthroplasty was determined for all except the five latter patients. Thus, the outcome of 322 (98 per cent) of the 330 arthroplasties was known at the latest follow-up evaluation. Radiographs were available for sixty-three of the eighty-three patients (seventy-six [78 per cent] of the ninety-eight hips) who were alive for the entire follow-up period. Of the ninety-eight hips in the living patients, eighty-three (85 per cent) caused no pain, fourteen (14 per cent) caused mild pain, and one (1 per cent) caused moderate pain. Fifty-two hips (53 per cent) were in patients who did not use walking aids, and only seven (7 per cent) were in patients who used support for walking because of the hip. At the minimum twenty-year follow-up, thirty-two (10 per cent) of the 322 hips that had been followed had been revised: eight (2 per cent), because of loosening with infection; twenty-one (7 per cent), because of aseptic loosening; and three (1 per cent), because of dislocation. Of the ninety-eight hips of the patients who were still alive, fifteen (15 per cent) had been revised: three (3 per cent), because of loosening with infection; eleven (11 per cent), because of aseptic loosening; and one (1 per cent), because of dislocation. The rate of revision due to aseptic loosening of the acetabular component in all 322 hips was 6 per cent (eighteen hips), while in the ninety-eight hips of the patients who were alive at least twenty years after the arthroplasty, it was 10 per cent (ten hips). The rate of revision because of aseptic loosening of the femoral component in all 322 hips was 2 per cent (eight hips), while in the ninety-eight hips of the living patients, it was 3 per cent (three hips).(ABSTRACT TRUNCATED AT 400 WORDS)

Ligamentous laxity across C0-C1-C2 complex. Axial torque-rotation characteristics until failure.

The axial torque until failure of the ligamentous occipito-atlanto-axial complex (C0-C1-C2) subjected to axial angular rotation (theta) was characterized using a biaxial MTS system. A special fixture and gearbox that permitted right axial rotation of the specimen until failure without imposing any additional constraints were designed to obtain the data. The average values for the axial rotation and torque at the point of maximum resistance were, respectively, 68.1 degrees and 13.6 N-m. The specimens offered minimal resistance (approximately 0.5 N-m), up to an average axial rotation of 21 degrees across the complex. The torque-angular rotation (T-theta) curve can be divided into four regions: regions of least and steadily increasing resistances, a transition zone that connects these two regions, and the increasing resistance region to the point of maximum resistance. The regions of least and steadily increasing resistances may be represented by two straight lines with average slopes of 0.028 and 0.383 N-m/degree, respectively. Post-test dissection of the specimens disclosed the following. The point of maximum resistance corresponded roughly to the value of axial rotation at which complete bilateral rotary dislocation of the C1-C2 facets occurred. The types of injuries observed were related to the magnitude of axial rotation imposed on a specimen during testing. Soft-tissue injuries alone (like stretch/rupture of the capsular ligaments, subluxation of the C1-C2 facets, etc.) were confined to specimens rotated up to or close to the point of maximum resistance. The specimens that were subjected to rotations up to the point of maximum resistance of the curve spontaneously reduced completely on removal from the testing apparatus. Spontaneous reduction was not possible for specimens tested slightly beyond their points of maximum resistance.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of effectiveness of a facet wiring technique: an in vitro biomechanical investigation.

The effects of facet wiring procedure commonly used for stabilizing cervical spines after laminectomy or bilateral facet dislocation on the motion behavior of whole cervical spines are investigated using a Selspot II system. A fresh human ligamentous intact specimen was potted at T1/T2 vertebra and clinically relevant loads applied to the topmost vertebra (C2) of the specimen. The resulting three rotational components of each of the five vertebral bodies (C3-C7) were recorded. Specimen was injured to mimic total laminectomies at C5 and C6 vertebral levels and tested again. The injured specimen was stabilized, using a facet wiring construct, across C4-C7 segment before testing for the final time. The injured specimens, compared to the intact specimens, demonstrated an increase in flexion-extension of about 10%. Facet wiring imparted stability to the cervical spine by stiffening segments up to roughly four times intact values.

Kinematics of the cervical spine: effects of multiple total laminectomy and facet wiring.

The effect of multiple-level total laminectomies followed by stabilization on the load-deformation behavior of the cervical spine is described. Fresh human ligamentous cervical spines (C2-T2) were potted and clinically relevant load types applied via a loading frame attached to the C-2 vertebra of the specimen. A set of three infrared light-emitting diodes (LEDs) were attached rigidly to each of five vertebrae (C3-7) to record their spatial locations after each load step application, using a Selspot II system. The specimen was tested again after total laminectomy performed on C5. The supraspinous, interspinous, and flavum ligaments between the C4-5 and C5-6 motion segments were cut; thereafter, the vertebral arch was removed. The specimen testing was resumed after inducing injury at C-6 in a similar fashion. The specimen was stabilized, using a facet wiring construct, across the C4-7 segment before testing for the final time. The load-deformation data of the injured and stabilized tests were normalized with regard to the corresponding results of the intact test. In flexion-extension mode, an increase in motion of about 10% after laminectomies was observed. Facet wiring was found to be an effective technique to stabilize injured cervical spines (approximately equal to 80% reduction in motion, compared with intact spines, was observed.

Comparison of the Quantum II Bacterial Identification System and the AutoMicrobic System for the identification of gram-negative bacilli.

The Quantum II Bacterial Identification System (BID; Abbott Laboratories) is a microprocessor-based spectrophotometric system for identification within 4 to 5 h of both enteric and nonenteric gram-negative bacilli. We compared the BID with the AutoMicrobic System (AMS; Vitek Systems, Inc.), using the most recent gram-negative identification card and software (AMS-GNI), for the identification of 501 clinical isolates of gram-negative bacilli, including 382 belonging to the Enterobacteriaceae and 119 nonenteric organisms. The API 20E (Analytab Products) was used as the reference system. The BID correctly identified 375 (98.2%) of the Enterobacteriaceae isolates and 111 (93.2%) of the nonenteric isolates; the AMS-GNI correctly identified 374 (97.9%) and 115 (96.6%) isolates, respectively. The BID identified all isolates within 5 h, whereas the AMS-GNI identified only 35% within this time period. The BID performed comparably to the AMS-GNI for the identification of most gram-negative bacilli. Simplicity, speed, and relatively low reagent cost make the BID a competitive system for many clinical laboratories.