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Publications (5)6.15 Total impact

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    ABSTRACT: We measured bone texture parameters of excised human femurs with a new device (BMA™). We also measured bone mineral density by DXA and investigated the performance of these parameters in the prediction of failure load. Our results suggest that bone texture parameters improve failure load prediction when added to bone mineral density. Bone mineral density (BMD) is a strong determinant of bone strength. However, nearly half of the fractures occur in patients with BMD which does not reach the osteoporotic threshold. In order to assess fracture risk properly, other factors are important to be taken into account such as clinical risk factors as well as macro- and microarchitecture of bone. Bone microarchitecture is usually assessed by high-resolution QCT, but this cannot be applied in routine clinical settings due to irradiation, cost and availability concerns. Texture analysis of bone has shown to be correlated to bone strength. We used a new device to get digitized X-rays of 12 excised human femurs in order to measure bone texture parameters in three different regions of interest (ROIs). We investigated the performance of these parameters in the prediction of the failure load using biomechanical tests. Texture parameters measured were the fractal dimension (Hmean), the co-occurrence matrix, and the run length matrix. We also measured bone mineral density by DXA in the same ROIs as well as in standard DXA hip regions. The Spearman correlation coefficient between BMD and texture parameters measured in the same ROIs ranged from -0.05 (nonsignificant (NS)) to 0.57 (p = 0.003). There was no correlation between Hmean and co-occurrence matrix nor Hmean and run length matrix in the same ROI (r = -0.04 to 0.52, NS). Co-occurrence matrix and run length matrix in the same ROI were highly correlated (r = 0.90 to 0.99, p < 0.0001). Univariate analysis with the failure load revealed significant correlation only with BMD results, not texture parameters. Multiple regression analysis showed that the best predictors of failure load were BMD, Hmean, and run length matrix at the femoral neck, as well as age and sex, with an adjusted r (2) = 0.88. Added to femoral neck BMD, Hmean and run length matrix at the femoral neck (without the effect of age and sex) improved failure load prediction (compared to femoral neck BMD alone) from adjusted r (2) = 0.67 to adjusted r (2) = 0.84. Our results suggest that bone texture measurement improves failure load prediction when added to BMD.
    Osteoporosis International 06/2011; 23(4):1311-6. · 4.04 Impact Factor
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    ABSTRACT: L’objectif de ce travail était d’étudier les résultats de l’arthroplastie totale du genou dans les raideurs de la flexion dans les gonarthroses post-traumatiques et décrire les particularités techniques de leur prise en charge. Une série multicentrique de 40 patients, avec une flexion de genou inférieure ou égale à 90°, a été sélectionnée à partir de 152 gonarthroses post-traumatiques sur cal vicieux. L’hypothèse est que le taux de complications de l’arthroplastie est plus élevé que dans les autres étiologies de raideur et nécessite une prise en charge spécifique. Patients Dans 23 cas, il y avait un cal vicieux intra-articulaire, dans 15 cas extra-articulaire et dans deux cas mixte. La flexion moyenne était de 72 ± 23°, l’extension de 6 ± 6° et l’amplitude de 66 ± 23°. Huit raideurs étaient sévères (flexion inférieure à 50°), six moyennes (flexion de 50 à 70°) et 26 modérées. Dans 14 cas, la tubérosité tibiale antérieure a été levée (43 % des cals intra-articulaires et 26 % des cals extra-articulaires). Cinq ostéotomies de réaxation simultanées ont été nécessaires. Dans les raideurs sévères, cinq libérations du quadriceps ont été associées. Résultats Quatre mobilisations sous anesthésie générale (AG) ont été pratiquées. Dans les raideurs sévères, on notait trois avulsions du tendon patellaire, deux nécroses cutanées dont une avec une infection profonde, et une autre infection profonde. Dans les raideurs modérées, on notait une pseudarthrose de la tubérosité tibiale et deux reprises pour descellement, l’un aseptique, l’autre septique. Avec un recul moyen de 5 ± 4 ans, la flexion moyenne était de 99,4 ± 23° soit un gain de 26,7± 20°. La flexion finale et le gain de flexion étaient corrélés à la flexion préopératoire (r = 0,62 et r = –0,47). L’amplitude finale était de 99 ± 27°, soit un gain moyen de 33 ± 21°. Les gains de flexion étaient comparables quel que soit le type du cal vicieux, intra- ou extra-articulaires. Discussion L’arthroplastie a permis un gain de flexion substantiel. Le soulèvement de la tubérosité tibiale et les ostéotomies de réaxation doivent être pratiqués si nécessaire, sans risque d’obérer le résultat. Des gains supérieurs peuvent être recherchés dans les raideurs sévères en libérant l’appareil extenseur, en l’absence de rétractions cutanées cicatricielles et d’antécédents infectieux récents. Niveau d’évidence Étude rétrospective non comparative de niveau 4.
    Revue de Chirurgie Orthopédique et Traumatologique 02/2011; 97(1):31–36.
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    ABSTRACT: Mycetoma is a chronic granulomatous infection caused by environmental fungi or bacteria. It affects dermal and subcutaneous tissues, with putative contiguous extension to muscles or bones. While common in tropical and subtropical areas, mycetoma is rare in Europe. We describe a case of Actinomadura meyerae osteitis in a 49-year-old Caucasian woman who suffered a tibia open fracture contaminated with hay; to the best of our knowledge the first case of autochthonous A. meyerae infection reported in France. The bacterium was cultivated from a bone biopsy. Following surgical osteosynthesis and six months of treatment with cotrimoxazole, our patient made a full recovery. Our case report suggests that A. meyerae is a potential agent of wound infection in farm workers in contact with hay.
    Journal of Medical Case Reports 01/2011; 5:32.
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    ABSTRACT: The objective of this study is to investigate the results of total knee arthroplasty (TKA) in traumatic osteoarthritis cases with flexion restriction and to describe the technical details of their management. A multicentre series comprising 40 patients with limitation of flexion less than or equal to 90° was selected from 152 cases of post-traumatic knee arthritis with malunion. We hypothesized that the arthroplasty complication rate would be higher than in other etiologies of limitation of flexion and would require specific management strategies. In 23 cases, intra-articular malunion was present, in 15 cases extra-articular, and in two cases combined. The mean flexion was 72±23°, extension was 6±6°, and total range of motion (ROM) 66±23°. Eight cases of flexion restriction were severe (flexion<50°), six intermediate (flexion, 50-70°) and 26 moderate. In 14 cases, the anterior tibial tuberosity was osteotomized (43% intra-articular malunion and 6% extra-articular malunion). Five simultaneous realignment osteotomies were necessary. In severe cases of limitation of flexion, five extensive quadriceps releases were associated. Four mobilizations under general anesthesia were performed. In the cases of severe limitation of flexion, we noted three avulsions of the patellar tendon, two cases of cutaneous necrosis, one of which was associated with deep infection, and another case of deep infection. In the cases of moderate limitation of flexion, we noted one case of nonunion of the tibial tuberosity and two cases were revised for loosening, one aseptic and the other septic. With a mean follow-up of 5±4 years, the mean flexion was 99.4°±23 for a gain of 26.7±20°. The final flexion and the gain in flexion were correlated with preoperative flexion (r=0.62 and r=-0.47, respectively). The final amplitude was 99±27° for a gain of 33±21°. The flexion gains were comparable for both types of malunion, whether they were intra- or extra-articular. Arthroplasty provided a substantial gain in flexion. Osteotomy of the tibial tuberosity and the realignment osteotomies should be performed if necessary, with no risk of compromising the result. Superior gains can be sought in severe cases of limitation of flexion by releasing the extensor apparatus, in absence of cutaneous scar tissue retractions and recent infection. Level 4. Noncomparative retrospective study.
    Orthopaedics & Traumatology Surgery & Research 12/2010; 97(1):28-33. · 1.06 Impact Factor
  • Orthopedics 10/2004; 27(9):967-8. · 1.05 Impact Factor