Standing radiological analysis with a low-dose biplanar imaging system (EOS system) of the position of the components in total hip arthroplasty using an anterior approach: a cohort study of 102 patients.

AIMS: The primary aim of this study was to analyse the position of the acetabular and femoral components in total hip arthroplasty undertaken using an anterior surgical approach. PATIENTS AND METHODS: In a prospective, single centre study, we used the EOS imaging system to analyse the position of components following THA performed via the anterior approach in 102 patients (103 hips) with a mean age of 64.7 years (sd 12.6). Images were taken with patients in the standing position, allowing measurement of both anatomical and functional anteversion of the acetabular component. RESULTS: The mean inclination of the acetabular component was 39° (standard deviation (sd) 6), the mean anatomical anteversion was 30° (sd 10), and the mean functional anteversion was 31° (sd 8) five days after surgery. The mean anteversion of the femoral component was 20° (sd 11). Anatomical and functional anteversion of the acetabular component differed by > 10° in 23 (22%) cases. Pelvic tilt was the only pre-operative predictive factor of this difference. CONCLUSION: Our study showed that anteversion of the acetabular component following THA using the anterior approach was greater than the recommended target value, and that substantial differences were observed in some patients when measured using two different measurement planes. If these results are confirmed by further studies, and considering that the anterior approach is intended to limit the incidence of dislocation, a new correlation study for each reference plane (anatomical and functional) will be necessary to define a 'safe zone' for use with the anterior approach. TAKE HOME MESSAGE: EOS imaging system is helpful in the pre-operative and post-operative radiological analysis of total hip arthroplasty.

Severe corrosion after malpositioning of a metallic head over the Morse taper of a cementless hip arthroplasty. A case report.

Morse tapers are frequently used in total hip replacement to achieve precise adjustment of lengths and femoral offset. Mechanically, they do not raise any specific problems so long as strict positioning requirements are observed and elements from different manufacturers are not mixed together. We report a case in which the implant induced unexplained pain at 2 years, in relation to a defective fit between the metallic head and the Morse taper. Asymmetric partial fit of the head onto the taper was detected on control X-ray and was implicated as causing metallosis due to excessive release of metal debris from the Morse taper. Revision required femoral stem exchange because of the damage to the Morse taper as well as replacing the cup with new metal-metal bearings. Evolution was favorable at 3 years' follow-up. Most hip replacements include a Morse taper; the present clinical case is a reminder that strict positioning rules are to be respected, without which corrosion and wear may lead to mechanical failure.

[Fracture of the distal radius associated with an articular comminutive fracture of the distal ulna: treatment in emergency by osteosynthesis of the radius by volar locking plate for the radius and a resection of the distal end of the ulna: report of one case]. / Fracture à bascule postérieure du radius distal associée à une fracture comminutive articulaire de l'ulna distal: traitement en urgence par ostéosynthèse du radius par plaque verrouillée antérieure et résection de l'extrémité distale de l'ulna: à propos d'un cas.

The authors present a case of a distal radius fracture associated with a comminutive fracture of the ulna head, treated by volar locking plate for the radius fracture and ulnar head resection. We obtain an early good objective and subjective functional result, whereas this type of fracture is classically associated with bad results in the series published with other treatments. This result needs to be confirmed by a more exhaustive series.

[Avascular necrosis of the capitate: a case report and a review of the literature]. / Ostéonécrose aseptique du grand os et traitement : à propos d'un cas et d'une revue de la littérature.

We report the rare case of a patient with an avascular necrosis of the proximal part of the capitate, with a review of the literature. The patient was treated by a resurfacing prosthesis of the proximal part of the capitate. At 22 month of follow up, the patient had a good functional result. Resurfacing prosthesis is a good therapeutic option in case of proximal capitate avascular necrosis when there is no more place for conservative surgery.

[Combined carpometacarpal dislocations, hand lesions and fractures of the two bones of the forearm: a report of two cases]. / Luxations spatulaires et lésions associées de la main et des deux os de l'avant-bras. A propos de deux cas.

The authors report two cases of complete dorsal carpometacarpal dislocations associated with lesions of the hand and the two bones of forearm. These dislocations are rare, and their clinical and radiological diagnosis is difficult. These cases are original through the association of carpometacarpal dislocation with lesions of the two bones of forearm. They demonstrate the need to stress the importance of a complete evaluation of the patient. Treatment must be immediate and begin with the osteosynthesis of the proximal lesions to avoid any irreducibility. These elements will determine the functional outcome.

Pagetic vertebral ankylosis and diffuse idiopathic skeletal hyperostosis.

STUDY DESIGN: A retrospective radiologic analysis of Paget's disease of the spine. OBJECTIVES: The prevalence, anatomic distribution, mechanisms of formation of Pagetic vertebral ankylosis (PVA) and the possibility of a relationship to diffuse idiopathic skeletal hyperostosis (DISH) were assessed in a large population of persons with Paget's disease. SUMMARY OF BACKGROUND DATA: Acquired vertebral ankylosis is not a common feature of the Paget's disease of the spine and its mechanisms of formation remain unknown. In some reports, PVA was associated with radiographic signs of DISH. METHODS: Of 337 Pagetic patients monitored in the Division of Rheumatology from 1961 to 1990, all 245 who had entire spine radiographs were selected for study. Radiographs were studied for signs of Pagetic vertebral lesions and for spinal lesions of DISH. RESULTS: The study group contained 156 men with a mean age of 68 years (range 37-92) and 89 women with a mean age of 71 years (range 50-89). Fourteen PVA were observed on the radiographs of 11 men (mean age 68 years; range 60-76). One PVA was cervical, eight were thoracic, one thoracolumbar, three lumbar, and one lumbosacral. Eighty of the two hundred forty-five patients (32.6%) had characteristic features of DISH. Eight out of the eleven patients with PVA also had evidence of spinal lesions of DISH and radiographic features of DISH were observed contiguous to ten of the fourteen PVA. CONCLUSIONS: The scarcity of PVA reported in the literature and in our study (4.4% of 245 patients) suggests that constant progression of the disease from one vertebra to another by invasion of intervertebral disc space is rare. However, the higher incidence of PVA in men, their preferential location at the thoracic spine and their association with lesions of DISH suggest that progression of Pagetic lesions by invasion of bridging osteophytes may be an important mechanism for the intervertebral spread of Paget's disease.

[Mechanisms of spinal block formation in Paget disease of bone. Radiographic study based on 14 cases]. / Mécanismes de formation des blocs vertébraux pagétiques. Etude radiographique à partir de 14 blocs.

Vertebral bridging occurs in approximately 10% of patients with spinal pagetic lesions. Diffuse idiopathic skeletal hyperostosis has been reported in patients with pagetic block vertebras and may facilitate vertebral fusion and extension of pagetic lesions. High prevalences of diffuse idiopathic skeletal hyperostosis have been found in patients with Paget's disease. To determine how pagetic block vertebras develop and to investigate relationships between Paget's disease and diffuse idiopathic skeletal hyperostosis, 244 patients with Paget's disease were studied retrospectively. Diagnostic criteria for diffuse idiopathic skeletal hyperostosis were the presence of flowing ossification along the anterolateral aspect of at least three contiguous vertebral bodies or presence of at least two anterolateral intervertebral bony bridges in the same spinal segment. Eight (33%) of the 244 patients had diffuse idiopathic skeletal hyperostosis. Two-thirds of patients with both conditions were male. There was no statistically significant association between presence of diffuse idiopathic skeletal hyperostosis and spinal involvement by Paget's disease. Fourteen pagetic block vertebras were identified in 11 male patients. Eight of these 11 patients had involvement of the fused vertebras or adjacent vertebras with diffuse idiopathic skeletal hyperostosis. Our findings confirm that diffuse idiopathic skeletal hyperostosis is common in patients with Paget's disease. The statistically significant association between diffuse idiopathic skeletal hyperostosis and pagetic vertebral fusion in the same site suggests that the former condition may be a risk factor for pagetic vertebral bridging.

[Bone complications during the treatment of osteoporosis with fluor]. / Complications osseuses au cours du traitement des ostéoporoses par le fluor.

Fourteen osteoporotic women who had been under treatment with fluoride (23 mg/day of fluorine ions) for 12 months on average developed periarticular pain in the lower limbs or pelvis, corresponding to 21 fractures due to bone insufficiency. Six of these fractures were revealed only by radionuclide uptake in the painful areas, whereas the remaining 15 fractures, including 2 of the sacrum, were visible at radiography. Four patients had a past history of hyperthyroidism or were in a state of active hyperthyroidism detected by hormonal assays and iliac bone biopsy when the fractures were diagnosed. The decalcification associated with hyperthyroidism facilitates the occurrence of bone insufficiency fractures, as do treatments with high doses of fluoride, inadequate calcium supplement intake (observed in 5 cases) or the presence before treatment of renal impairment or disorders of bone mineralization, sometimes detected only by iliac bone biopsy. Repeated measurements of blood and urinary fluoride levels during treatment make it possible to adjust fluoride dosage, and lower doses (14 mg/day of fluorine ions) might reduce the incidence of the adverse effects of fluoride on bone.

[Insufficiency fractures of the sacrum. 5 cases]. / Fractures de contrainte du sacrum. Cinq observations.

Five cases of insufficiency fracture of the sacrum in women aged over 60 are reported. The elements of diagnosis and causative factors are reviewed. In all cases the diagnosis was confirmed by technetium bone scintigraphy and computerized tomography of the sacrum. Bone tissue evaluation in search of a bone-wasting disease, the principal cause of this type of fracture, was conducted in all 5 patients, using photon absorptiometry and/or double energy computerized tomography and histomorphometry. These examinations provided detailed information on disorders of mineralization in the genesis of these insufficiency fractures.