ABSTRACT
PURPOSE: To compare the accuracy of four wear measurement methods using 17 retrieved polyethylene liners previously used in revision hip arthroplasty. MATERIAL AND METHOD: Direct measurement was done using a point contact micrometer. Three manual measurement methods and Devane's three dimensional computerized method were compared. RESULT: Dorr's method underestimated wear by 26.2% with a mean error of 0.39 mm. Livermore's method estimated wear to within 22.4%, with a mean error of 0.21 mm, Devane's method estimated wear to within 12.1%, with a mean error of 0.14 mm. The new method (with correction factor adjustment by the Dorr method) estimated wear to within 13.4%, with a mean error of 0.17 mm. CONCLUSION: The new method can more accurately estimate average acetabular cup wear.
Subject(s)
Acetabulum , Arthroplasty , Arthroplasty, Replacement, Hip , Hip , PolyethyleneABSTRACT
A 60-year-old man visited our hospital complaining of an inability to actively extend his left knee beyond 45 degrees for seven months after a slip down injury. Twenty years earlier he had sustained a falling down injury to the left knee and had undergone a patellectomy due to comminuted patellar fracture. In the operating room, a defect in the patellar tendon was demonstrated. As the knee was flexed, the medial and lateral portions of the defect in the patellar tendon separated and moved posterioly over the femoral condyles, producing a boutonniere effect. The scarred lateral retinacula and vastus lateralis were released, allowing the medial and lateral portions of the patellar tendon to be brought together. These were then reefed and sutured together, forming a cord that rode in the intercondylar notch. Twelve months postoperatively the knee had an active range of motion from 0 degrees through 120 degrees.
Subject(s)
Humans , Middle Aged , Cicatrix , Congenital Abnormalities , Knee , Operating Rooms , Patellar Ligament , Quadriceps Muscle , Range of Motion, ArticularABSTRACT
A 33-year-old female visited to our hospital complaining of severe painful swelling in her right buttock. Ten hours previously, she had fallen down stairs. Motor power of her ankle and foot were zero to trace and the intracompartment pressure of the gluteal region was 50 mmHg. MRI showed diffuse intramuscular edema of right gluteal muscle. Emergency fasciotomy of the gluteal compartment was per-formed and her neurologic signs gradually improved at a postoperative 24 hours. She recovered completely at postoperative 14 days without further sequelae.
Subject(s)
Adult , Female , Humans , Ankle , Buttocks , Compartment Syndromes , Edema , Emergencies , Foot , Magnetic Resonance Imaging , Neurologic Manifestations , Sciatic NeuropathyABSTRACT
The medial collateral ligament(MCL) of the knee is the well established secondary restraint to the anterior displacement of the knee joint. However, there has been no report about the estimation of the anterior displacement in combined ACL(anterior collateral ligament) and MCL injures according to period when they were treated with conservative measures. This prospective study evaluated the changes of anterior displacement over time in combined ACL/MCL injury as the MCL injury heals after initial conservative measures. 19 patients who had combined ACL/MCL injury were followed during twelve months after injury. All patient had a positive Lachman test and were evaluated the side to side differences on KT-2000 knee arthrometer(Medmetric, San Diego, California) testing under 20 Ibs anterior tibial loading at 30 degree knee flexion. The stability of the knee was assessed using KT-2000 knee arthrometer every 8 weeks with clinical examination prospectively. They were treated with CI (Combined instability) brace (Smith & Nephew, Carlsbad, California) as conservative measures. Overall, Initial side to side difference of the anterior displacement was averaged 5.21mm (range,4.0-7.0mm) and 3.30mm (range,2.0-5.5mm) finally. According to the classification of MCL injury, in Grade III groups, they had the greatest initial anterior displacement about 6.4mm, but tight- ened the most to 3.08mm finally. In Grade II and Grade I groups they showed 2.97mm and 2.13mm side to side difference (p>0.01). However in Grade I, the anterior displacement were decreased by 4 months after injury but, it were increased at 6 months after injury. In Grade II and III, the decrement of the anterior displacement were continued by 6 months after injury, but they were not changed after that. The data was analyzed by General Linear Model Procedure method. Conclusively, the anterior displacement of knee in patients with combined ACL/MCL injury was diminished with the time in the majority of patients as the MCL healed. It means that the MCL was the stabilizer to the anterior displacement of the knee under the anterior tibial loading.