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J J Larkin

Publications and source records attributed to J J Larkin.

7 recordsLinked to original sources
PubMed1996

In vitro study of knee stability after posterior cruciate ligament reconstruction.

The effect of reconstructing the posterior cruciate ligament on anteroposterior laxity of the knee was evaluated in 7 cadaveric knees. A bone-patellar tendon-bone graft was used. Femoral pilot holes were drilled to locate the most isometric sites for attachment of the graft to the femur using an isometer. A tension of 89 N was set in the graft using a tensiometer with the knee in 90 degree flexion while applying an anterior drawer force of 156 N to the tibia. Posterior displacement of the knee was measured in 15 degree increments from O degree to 90 degrees in the intact knee, in the knee with the posterior cruciate ligament transected, and after reconstruction of the posterior cruciate ligament in response to 100 N of posteriorly applied force. Graft tension was nearly constant between 0 degrees and 90 degrees flexion, indicating the grafts to be isometric. The reconstruction reduced posterior translation of the tibia in the posterior cruciate ligament excised knee at all angles of flexion; the differences were statistically significant. The reconstruction returned posterior translation to levels not significantly different from those of the intact knee between 0 degrees and 45 degrees flexion but not in the greater angles of flexion tested.

Adult↗
PubMed1995

Digital chest radiography: comparison of unprocessed and processed images in the detection of solitary pulmonary nodules.

PURPOSE: To compare the accuracy with which simulated solitary pulmonary nodules can be identified on digital images of the chest that are unprocessed, processed with adaptive spatial filtering, or processed with global filtering. MATERIALS AND METHODS: Six experienced chest radiologists evaluated 408 test radiographs (136 from each of the three types, half with simulated nodules) and judged whether a nodule was present. Data from the 2,448 observations were evaluated by means of a receiver operating characteristic curve with location methods. RESULTS: Accuracy was significantly better with the adaptive filter technique than with the global technique (P < .05), and it was better with adaptive filtering than with no processing in the detection of pulmonary nodules in the mediastinal-subdiaphragmatic areas (P < .05). No significant difference was found between no processing and global filtering. CONCLUSION: Adaptive filtration is superior to global filtration in the identification of solitary pulmonary nodules and is superior to no processing in nodules projected over the radiopaque areas of the thorax on digital images.

Algorithms↗
PubMed1992

Assessment of the posterior malleolus as a restraint to posterior subluxation of the ankle.

We assessed the function of the posterior malleolus, the anterior tibiofibular ligament, and the fibula with regard to posterior stability of the talus in ten ankles of cadavera. Posteriorly directed loads of as much as 200 newtons were applied. Two groups of ankles were tested; in the first group, three ankles in which the ligamentous and osseous structures were intact were tested after transection of the posterior capsule and after removal of 10, 20, 30, and 40 per cent of the articular surface of the distal end of the tibia from the posterolateral corner. In the second group, seven ankles were tested in the same sequence, but the anterior tibiofibular ligament and the fibula were transected before sectioning of the articular surface. Compared with the results for the intact ankle, the experiments on the first group demonstrated less than one millimeter of additional posterior translation of the talus after removal of as much as 40 per cent of the articular surface. In the second group, in which the anterior tibiofibular ligament and the fibula had been transected, significant posterior translation of the talus (more than three millimeters) occurred after removal of 30 per cent of the articular surface (p < 0.01). This represented a 160 per cent increase in translation compared with that in the intact ankle.

Aged↗
PubMedDate not supplied

Human immunodeficiency virus infection in children.

The incidence of Acquired Immune Deficiency Syndrome (AIDS) in the pediatric population is increasing. Estimates are that in 1993 AIDS will be among the five leading causes of death in children. AIDS progresses more rapidly in children than in adults. It also has features that are unique to children, such as recurrent bacterial infections, bronchus-associated lymphoid tissue (BALT), and basal ganglia calcification. This review is written with emphasis on aspects of AIDS unique to children. Features of AIDS that are similar in adults are not discussed.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

The effect of injury chronicity and progressive rehabilitation on single-incision arthroscopic anterior cruciate ligament reconstruction.

We conducted a prospective study on 50 consecutive patients who received a single-incision arthroscopic patellar tendon autograft reconstruction for anterior cruciate ligament (ACL) rupture. The purposes were to determine if differences existed in results between patients with acute and chronic ACL ruptures, and if a progressive rehabilitation program could safely return patients to sports activities early without compromising knee stability. Forty-two patients (84%) returned for follow-up a mean of 31 months postoperatively. Twenty-one patients had acute ruptures, and 21, chronic ruptures. A progressive rehabilitation program was used by 28 patients (67%) who met strict criteria, which allowed early return to running and sports activities. The results were rated with the Cincinnati Knee Rating System. We found no effect of either injury chronicity or time to return to activity for 21 factors, including anterior-posterior displacement, patellofemoral crepitus, range of knee motion, quadriceps muscle strength, symptoms, functional limitations, or the patient rating of outcome. Using arthrometer and pivot-shift test data, 30 knees (71%) had a functional reconstruction; 8 knees (19%) had partial function; and 4 knees (10%) failed. Patients expressed satisfaction with the operation as follows: 23 (55%) rated their overall knee condition as normal; 16 (38%), very good; and 3 (7%), good. No patients rated their knee condition as fair or poor.

Acute Disease↗