Biomedical subjects

G Randelli

Publications and source records attributed to G Randelli.

At least 19 recordsLinked to original sources

PubMed1997

Periprosthetic bone density around fully hydroxyapatite coated femoral stem.

In this study, periprosthetic bone mineral density was measured at scheduled time intervals after surgery by dual energy x-ray absorptiometry in 21 patients to assess the history of bone density redistribution after femoral stem insertion. Measurements of changes in bone density with time were obtained for the regions of the greater trochanter, the lateral cortex, the tip, the medial cortex, and the calcar. In all regions, bone density decreased during the first 3 months after surgery; this was followed by a prolonged period of 18 to 30 months of bone gain, a subsequent period of steady state, and the final resumption of bone aging processes after the third postoperative year. The greatest loss was observed in the calcar region after 6 months (greater than 50%). The characteristic pattern of time related bone density changes obtained in this study may make it possible to compare other pathologic, design, or stiffness related patterns. This could have clinical relevance in the early diagnosis of pathologic processes and as a means of evaluating prosthetic designs.

Absorptiometry, Photon↗

PubMed1996

Analysis of the gait of adults who had residua of congenital dysplasia of the hip.

Twenty-one adult subjects who had symptomatic residua of unilateral congenital dysplasia of the hip, with various degrees of degenerative changes, were studied with respect to the physical and radiographic findings and gait performance. Three-dimensional body reconstruction; the Trendelenburg sign; spatiotemporal parameters of stride; ground-reaction forces; kinematics of the hip, knee, and ankle; moments of forces; and joint powers were evaluated bilaterally. The kinematic and kinetic parameters of the affected limb were compared with those of the unaffected limb and with those of the limbs of normal control subjects. Correlations between changes in selected gait parameters and the clinical and radiographic signs of impairment of the hip were demonstrated. The results are discussed in relation to the possible mechanisms underlying the observed alterations and in view of possible operative interventions.

Adult↗

PubMed1993

Dual X-ray absorptiometry for the evaluation of bone density from the proximal femur after total hip arthroplasty: analysis protocols and reproducibility.

Dual X-ray absorptiometry (DXA) instruments are now able to evaluate bone mineral density (BMD) of bone surrounding metal implants. The assessment of BMD around prosthetic components could provide additional information for the follow-up of total hip arthroplasty (THA). In this study, we evaluated the potential application of DXA in the field of THA. BMD was measured in the proximal femur of both THA and THA-free sides in 14 postmenopausal women 6-18 months after THA. The explored segment was divided into seven zones as proposed by Gruen et al. [18]. The precision error of BMD measurements ranged from 1.8 to 6.8% on the THA side and from 1.1 to 2% to the THA-free side. The reduction of BMD of the THA versus the THA-free side was significant in all seven zones (P < 0.01, t-test for paired data). These results showed significant differences in BMD around femoral components of THA with respect to contralateral healthy side, and demonstrate the sensitivity of DXA for detecting these changes.

Absorptiometry, Photon↗

PubMed1992

Prophylaxis with indomethacin for heterotopic ossification after Chiari osteotomy of the pelvis.

One hundred patients who had painful dysplasia of the hip were treated with a Chiari osteotomy of the pelvis, and the postoperative radiographs were reviewed for the development of heterotopic ossification. Sixty patients did not receive indomethacin postoperatively, and eighteen (30 per cent) had heterotopic ossification of at least class 1; forty patients received indomethacin for two weeks postoperatively, and only three (8 per cent) of them had heterotopic ossification. This difference was significant (p < 0.025). No class-3 or 4 heterotopic ossification was seen in the patients who were given indomethacin. The prevalence of side-effects was relatively low, and no delayed union of the osteotomy was observed in any patient. We concluded that indomethacin, in the dosage schedule and regimen that we used, provides effective prophylaxis for heterotopic ossification after a Chiari pelvic osteotomy.

Female↗

PubMed1971