Unicompartmental knee arthroplasty (UKA) is one surgical option for treating symptomatic medial osteoarthritis. Clinical studies have shown the functional benefits of UKA; however, the optimal alignment of the tibial component is still debated. The purpose of this study was to evaluate the effects of tibial coronal and sagittal plane alignment in UKA on knee kinematics and cruciate ligament tension, using a musculoskeletal computer simulation. The tibial component was first aligned perpendicular to the mechanical axis of the tibia, with a 7° posterior slope (basic model). Subsequently, coronal and sagittal plane alignments were changed in a simulation programme. Kinematics and cruciate ligament tensions were simulated during weight-bearing deep knee bend and gait motions. Translation was defined as the distance between the most medial and the most lateral femoral positions throughout the cycle.Objectives
Methods
One pattern of injury to the brachial plexus shows recovery of the fifth and sixth cervical nerves but little else. These patients have useful shoulders and functional elbow flexion, but elbow and wrist extension is weak or absent. Their hand function is negligible. We restored hand function in three such patients using free functioning muscle transfer for finger flexion and transfer of the sensory rami of the intercostal nerve to the ulnar nerve for sensation. Supplementary operations to restore elbow and wrist extension were necessary in one patient.
A case of the Jansen type of metaphysial dysostosis, followed for fifteen years from childhood to the age of nineteen, is reported. Radiographs taken at five years revealed the characteristic metaphysial changes in all the tubular bones, especially those of the hands and feet. The acetabular and glenoid areas, the costochondral junctions and the sternal ends of the clavicles were also involved. Radiographs taken at nineteen years, however, showed only marked deformities, which shows that the involvement of the metaphyses can regress by the end of growth. Biopsy of the lower end of radius at the age of twelve revealed changes in the growth plate or physis, especially in the zone of resting cartilage. This finding suggests that cellular function in this zone is disturbed by some unknown mechanism. Hence, the term physial dysostosis may be more accurate than metaphysial dysostosis.
