For 30 years, uncemented anatomic hip stems have been implanted with documented clinical results[1,2]. Their geometry can be linked back to the geometry of the PCA and ABG stems. Modifications to date include stem length, body geometry, material, and reduction in distal geometry. New tools have been developed allowing anatomical measurements and analysis of three-dimensional digital femora geometry through CT scans[3]. The purpose of this study is to analyze three-dimensional contact of various anatomic hip stem designs using this technique. Six femora (57–87 yrs, 72–88 kg), were selected from a CT scan database (SOMA™) of 604 Caucasian bones. They were selected based on femoral anteversion (average +/−1.5 * std. dev.) with three measuring[4] 8–10° and three 31–33° of anteversion. The CT scans were segmented into cancellous/cortical bone and converted into CAD models in PRO/Engineer Wildfire (v.5). A/P views of the bones were scaled to a 120% magnification to allow three surgeons to surgically template and choose the stem size and location (maximizing fill (n = 1); restoring the head center (n = 2)) with two implant designs (1-Citation TMZF and 2-ABG II Monolithic, Stryker Orthopaedics, Mahwah). Measurements from templating were used to virtually implant CAD models of the implants into the bones (n = 36 bone/stem assemblies). The assemblies were imported into Geomagic Qualify 2012 for 3D deviation analysis comparing the coated region of the implant to the cortical-cancellous boundary. The analysis generated color map profiles based on the following categories: Contact (−2.0 to 0.5 mm), Conformity (0.5 to 2.0 mm), Proximity (2.0 to 5.0 mm), and Gap (5.0 to 12 mm) and the percent of the surface that was within each of these categories. These results were compared for patterns within and across the anatomic families.Introduction:
Methods:
1. The tibialis posterior tendon was transferred in twenty-eight congenital club feet to maintain the correction obtained by serial wedge plasters. 2. There has been no relapse in twenty-seven of the twenty-eight feet in the period under review–namely, one to three years from operation. 3. The technique of the operation is described. 4. It appears that this operation should not be attempted when a soft-tissue correction has been done previously.
1. The results of seventy-six transfers of the tibialis anterior tendon to the outer side of the foot to prevent relapse of congenital club foot are reviewed. 2. There were relapses in fifty-two of the seventy-six feet on which the operation had been performed. 3. The equinus component of the deformity is the dominant feature in all the relapses. 4. A test for occult equinus is described. 5. The factors contributing to the high relapse rate are discussed.
1. Five patients with seven fatigue fractures of the lower third of the tibia are described; two had bilateral fractures. There is a striking similarity in the site and appearance of these fractures. 2. All occurred in middle-aged or elderly people without a history of unusual activity or illness. 3. The fractures are so nearly identical as to constitute an entity which, as far as we are aware, has not been described before.
1. A case of Fanconi's syndrome, with evidence of renal tubular dysfunction, is reported. 2. Healing of the rachitic lesions followed massive doses of calciferol. There was simultaneous improvement in the biochemical state. This case is probably unique in that the amino-aciduria disappeared. 3. Two-stage osteotomies were undertaken for the correction of severe bowing of the tibiae. 4. No toxic symptoms have developed so far from the calciferol therapy.