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P Anract

Publications and source records attributed to P Anract.

At least 19 recordsLinked to original sources
PubMed2006

[Electromyographic study of stretch reflexes in the normal and prosthetic hip].

PURPOSE OF THE STUDY: Several studies have been devoted to the effect of proprioception on joint function. Modifications in feedback control from the cord have been observed in unstable joints due to capsule and ligament laxity. A few studies have examined the effect of knee and hip arthroplasty on proprioception, but none have established whether stretch reflexes affect function of a prosthetic joint. The purpose of the present study was to demonstrate the electromyographic characteristics of stretch reflexes of the normal hip joint and to compare them with those observed in the prosthetic hip. MATERIAL AND METHODS: Two groups of patients were studied. The first included eleven subjects free of neurological disorders whose studied limb was healthy. The second group included ten subjects with a total hip prosthesis who had undergone extensive capsulectomy during the arthroplasty. Voluntary muscle contraction was noted in each subject. In addition, electromyographic recordings were made to note response of the ipsilateral and contralateral quadriceps crural and tensor of the fascia lata during changes in joint position. Recordings were made with the subject in the supine position, the limb suspended, hip flexed at 45 degrees and knee extended. Three series of ten recordings were made in random order to measure the latency of muscle response to free fall of the limb, accelerated fall of the relaxed limb, and accelerated fall associated with calibrated contraction of the quadriceps. Mean latency of muscle response was calculated for each trial. RESULTS: In the conditions of this study, there was no statistically significant difference (p = 0.05) in the reflex time course between natural and prosthetic hips. DISCUSSION: Changes due to joint replacement and capsulectomy do not appear to affect the stretch reflexes of the hip joint.

Aged↗
PubMed2005

[Twenty nine shoulder reconstructions after resection of the proximal humerus for neoplasm with mean 7-year follow-up].

PURPOSE OF THE STUDY: Techniques available for shoulder reconstruction after resection of a tumor of the proximal humerus include scapulohumeral arthrodesis, humerus prosthesis with or without an allograft, inverted prostheses, and massive allografts. The purpose of this study was to review clinical and radiological outcomes in a series of 29 patients (20 men and 9 women) who underwent resection-reconstruction of the proximal humerus and to establish from these cases a decision making algorithm for therapeutic indications as a function of tumor invasion. MATERIAL AND METHODS: The tumors were 20 chondrosarcomas, five osteosarcomas, two Ewing sarcomas and one malignant hemangiopericytoma. In 17 patients epiphyso-metaphyseal or epiphyso-metaphyso-diaphyseal resection was performed with preservation of the abductor muscles (type S34A or S345A according to the Musculoskeletal Tumor Society classification). For 12 patients epiphyso-metaphyseal or epiphyso-metaphyso-diaphyseal resection was performed without preservation of the abductor muscles (type S34B or S345B). Reconstruction was achieved using a centromedullary cemented nail in one patient, scapulohumeral arthrodesis in three, a massive humerus prosthesis in 15, and composite humerus prosthesis in three and an inverted prosthesis in seven. The functional score of the Musculoskeletal Tumor Society (MSTS) and standard x-rays were used to assess outcome. RESULTS: Mean follow-up was 85 months (range 16-300). The mean MSTS score was 88% for inverted prostheses, 76% for composite prostheses, 72.6% for massive prostheses, 75% for scapulohumeral arthrodeses, 67% for massive prostheses, and 80% for cemented centromendullary nail. Five patients died from their malignant disease and one from another cause. Four patients are alive but with active disease after a mean follow-up of 108 months and 19 patients (65.5%) are alive and free of locoregional recurrence or metastasis after a mean 83.5 months. We had 28 complications. Glenohumeral instability was the most frequent (11 cases). DISCUSSION: Resection of the upper portion of the humerus should be performed to achieve cancerologically satisfactory tumor resection and enable shoulder resection, if possible, with preservation of a viable and functional abductor system. The functional outcome after such reconstruction depends on the type of bony resection, but also on the sacrifice of the rotator cuff and the deltoid muscle. In light of our experience and results in the literature, we advocate, despite the small number of cases for the different reconstructions, the following decision-making algorithm after resection of the proximal humerus without joint invasion: when the resection removes the rotator cuff and the deltoid (or the axillary nerve), there are two options: scapulohumeral arthrodesis or massive humerus prosthesis for patients who do not desire a complex therapy with a long postoperative period; when the resection preserves the rotator cuff and/or the deltoid muscle, reconstruction can be achieved with a composite (inverted or not) prosthesis with suture of the cuff tendons. We prefer the inverted composite prosthesis; if the deltoid muscle can be preserved but not the rotator cuff, the composite inverted prosthesis appears to be the most logical solution, but scapulohumeral arthrodesis can be proposed in selected cases.

Adolescent↗
PubMed2004

Effects of transforming growth factor-beta on aggrecanase production and proteoglycan degradation by human chondrocytes in vitro.

OBJECTIVE: Aggrecan is degraded by Aggrecanases (ADAMTS-4 and -5) and MMPs, which cleave its core protein at different sites. Transforming growth factor (TGF)beta is known to stimulate matrix formation in cartilage, and ADAMTS-4 production in synoviocytes. The aim of this in-vitro study was to examine the effects of TGFbeta on aggrecanase production in human cartilage. DESIGN: Expression of ADAMTS-4 and -5 in chondrocyte cultures from normal or osteoarthritic cartilage was studied at mRNA level by RT-PCR. Aggrecanase activity was examined by western blot of aggrecanase-generated neoepitope NITEGE, and by measure of proteoglycan degradation in cartilage explants. RESULTS: TGFbeta strongly increased mRNA levels of ADAMTS-4, while ADAMTS-5 was expressed in a constitutive way in chondrocytes from normal and osteoathritic cartilage. TGFbeta also increased NITEGE levels and proteoglycan degradation. Addition of an aggrecanase inhibitor blocked the increase of NITEGE, and partially inhibited proteoglycan degradation. CONCLUSIONS: TGFbeta stimulates ADAMTS-4 expression and aggrecan degradation in cartilage. This catabolic action seems to be partially mediated by aggrecanases. It is, therefore, proposed that the role of TGFbeta in cartilage matrix turnover is not limited to anabolic and anti-catabolic actions, but also extends to selective degradation of matrix components such as aggrecan.

ADAM Proteins↗
PubMed2004

[Trauma-induced tears of the quadriceps tendon: 47 cases].

PURPOSE OF THE STUDY: A torn quadriceps tendon is an exceptional finding generally observed after high-energy knee trauma in patients over 40 who present a sprain-like syndrome or after low-energy trauma in elderly subjects who experience knee instability. We reviewed a series of 47 cases of traumatic quadriceps tendon tears treated between 1976 and 1996 in order to evaluate outcome after surgical repair. MATERIAL AND METHODS: Clinical diagnosis was the rule. Forty-two patients, mean age 55 years (range 17-92) were treated for tears of one or both quadriceps tendons subsequent to low-energy trauma (40 tears) or high-energy trauma in younger subjects. The diagnosis was established early in all cases except eight (diagnosis at three weeks to one year). Surgical repair was performed in all cases except one. After surgery, the knee was either immobilized with a plaster cast or held in a removable splint to allow early mobilization. RESULTS: Average time to recovery compatible with daily life or occupational activities was four months. Recovery was not complete at this time. Long-term follow-up revealed that complete recovery with very good or good subjective results was achieved in 90% of the cases. Complete joint motion and normal quadriceps force was achieved in 80% of the cases. Patients who started rehabilitation exercises early generally achieved less satisfactory results although no significant correlation was identified with objective clinical variables. DISCUSSION: Quadriceps tendon tear is a clinical diagnosis which does not require complementary exploration for confirmation. Plain x-rays may be useful to identify associated bony lesions and specific signs of tendon tears. Early surgical repair followed by complete immobilization appears to be preferable for functional recovery allowing better recovery of muscle force without compromising flexion.

Activities of Daily Living↗
PubMed2004

DNA microarray allows molecular profiling of rheumatoid arthritis and identification of pathophysiological targets.

This study was undertaken to evaluate the possibility to obtain a molecular signature of rheumatoid arthritis (RA) comparatively osteoarthritis (OA), and to lay the bases to develop new diagnostic tools and identify new targets. Microarray technology was used for such an analysis. The gene expression profiles of synovial tissues from patients with confirmed RA, and patients with OA were established and compared. A set of 63 genes was selected, based, more specifically, on their overexpression or underexpression in RA samples compared to OA. Results for six of these genes have been verified by quantitative PCR using both samples identical to those used in the microarray experiments and entirely separate samples. Expression profile of the 48 known genes allowed the correct classification of additional RA and OA patients. Furthermore, the distinct expression of three of the selected genes was also studied by quantitative RT-PCR in cultured synovial cells. Detailed analysis of the expression profile of the selected genes provided evidence for dysregulated biological pathways, pointed out to chromosomal location and revealed novel genes potentially involved in RA. It is proposed that such an approach allows valuable diagnosis/prognostics tools in RA to be established and potential targets for combating the disease to be identified.

Adult↗
PubMed2003

Partial anterior trochanteric osteotomy in total hip arthroplasty: surgical technique and preliminary results of 127 cases.

The authors describe a new approach to the hip joint arthroplasty performed in 127 cases of total hip arthroplasty without major complication. A small anterior fragment of greater trochanter, maintaining the insertions of the gluteus minimus and vastus lateralis muscles, is detached. The whole insertion of the gluteus medius is preserved intact, providing good prosthetic stability and rapid recovery of abductor power and gait. Three months after surgery, 74% of patients had recovered good abductor strength with a Merle d'Aubigné and Postel score of 17 points. This surgical approach is technically easy to perform and provides good exposure of the hip. The osteotomized fragment is easily reattached using 2 cerclage wires, and upward displacement after operation was rarely seen.

Adult↗
PubMed2002

[Primary bone lymphoma. Retrospective immunohistochemical study of 22 cases].

PURPOSE OF THE STUDY: The clinical, biological, radiological, MRI, and histological features of 22 primary bone lymphomas were reviewed retrospectively. MATERIAL AND METHODS: The standard pathology slides were reexamined with an immunohistochemistry study. Results of two treatments, chemotherapy alone versus chemotherapy then radiotherapy, were compared in terms of local control and patient survival. RESULTS: Mean age of the patients was 53 years; male gender predominated (M/F=2/1). The most frequent clinical sign was pain and 32% of the patients had a pathological fracture. The long bones were generally involved. The typical radiographic image was a permeable bone defect. MRI demonstrated heterogeneous signals on the T2 images. Technetium scintigraphy (performed in all patients) was very sensitive. Histology generally described diffuse large centroblastic lymphoid cells, all with B phenotype. Twelve patients were treated with chemotherapy alone and eight with chemotherapy and radiotherapy. One patient was only given palliative treatment with corticosteroids due to major immunodepression. The last patient, a 79-year-old woman, developed a tumor of the femoral neck; at surgery section of the neck removed the entire tumor, but radiotherapy (30 Gy) centered on the femur was nevertheless performed. Only patients with fractures were operated. Mean follow-up in this series was 48 months (range 4-120). Mean 5-year Kaplan-Meier survival was 74.41% for the overall series, 83.33% for the chemotherapy group and 82.50% for the chemotherapy-radiotherapy group. DISCUSSION: We were unable to demonstrate any significant difference in survival between the two types of treatment. None of the patients experience local relapse. Our observations suggest that technetium scintigraphy is more sensitive than MRI and more specific for diagnosis. Radiography, together with clinical examination and is indicated to monitor these patients during and after treatment. Based on this series, patients with primary bone lymphoma should be given chemotherapy, either alone or combined with radiotherapy, rather than radiotherapy alone. Surgery is not indicated except to obtain a biopsy and to treat mechanical complications.

Antineoplastic Agents↗
PubMed2001

Complications and functional evaluation of 17 saddle prostheses for resection of periacetabular tumors.

Seventeen saddle prostheses were inserted between 1988 and 1997 after resection of periacetabular tumors. The tumors involved the zones II and III of Enneking classification in 13 patients, the zones I and II in 2 patients, and the zone II in 2 patients. The tumors included 11 chondrosarcomas, 3 Ewing sarcomas, 2 giant cells tumors, and 1 metastasis of renal carcinoma. The tumoral resection was wide "en bloc" in 14 cases, marginal in 2 cases, and intratumoral in 1 case. The mean follow-up period of the patients is 42 months ranging from 8 to 84 months. Local recurrences occurred in five cases and metastases in four cases. Five patients died of tumoral disease and one of intercurrent disease. Complications were observed in 11 cases (65%) including nerve damages (3 cases), deep infections (3 cases), upward migrations of the saddle (4 cases), saddle dislocations (3 cases), sacroiliac subluxations (2 cases), and mechanical failures (2 cases). The modified Musculoskeletal Tumor Society Score (MSTS) and the Toronto Extremity Salvage Score (TESS) were used for functional analysis. Functional results were available for only nine patients of the series with a mean MSTS of 17 points ranging from 11 to 23 points and a mean TESS of 58 points ranging from 39 to 95 points. The saddle prosthesis provided in all cases of this series an early painfree weight-bearing reconstruction with minimal limb shortening, but the functional results remained fair in most patients due to a limited range of motion and a poor abductor strength.

Acetabulum↗
PubMed2001

Long-term disability assessment after surgical treatment of low grade spondylolisthesis.

The aim of this study was to determine whether assessment of back surgery with disability scores is relevant. We also attempted to answer the question of whether this evaluation should be conducted by a surgeon or a medical doctor. This retrospective study analyzes the long-term outcome (average follow-up 7 years, range: 3-12) of 40 patients (mean age: 46.2 years) treated by posterior surgical decompression, posterolateral arthrodesis, with or without instrumentation, for symptomatic low-grade spondylolisthesis. All patients were interviewed postoperatively and examined the same day by an orthopedic surgeon, who was not involved in the patients' treatment, as well as by a medical doctor rehabilitation specialist. Impairment was assessed by a standardized clinical examination and by visual analog scales (VAS) of pain. Disability was assessed using two scales: the Quebec disability scale and the Beaujon scale. Anxiety and depression were assessed with a validated specific questionnaire (HAD). Patient's perceived handicap was assessed on a 100-mm VAS. Our results show that the scores of the two disability scales were highly correlated with the patient's overall satisfaction ( r = 0.73 and 0.77 for the Quebec scale and the Beaujon scale, respectively). The intraclass correlation coefficient showed very good or excellent correlation between the data collected by the surgeon and the rehabilitation specialist, ranging from 0.8 to 0.97. This finding clearly demonstrates that interview by a surgeon who is not involved in the patient's treatment does not influence the patient's assessment in terms of impairment, disability, or handicap. Moreover, our results suggest that disability scales are the most relevant outcome measures in the assessment of spine surgery.

Adult↗
PubMed2001

Knee reconstruction with prosthesis and muscle flap after total arthrectomy.

A massive prosthesis and medial gastrocnemius muscle transfer were used to reconstruct the knee after extracapsular en bloc excision for bone sarcoma. Magnetic resonance images showed intraarticular involvement. This technique was used in nine patients, six men and three women aged 18 to 51 years, with primary malignant bone tumors of the knee. Extraarticular resection of the knee, including the patella, was done in every case. A knee prosthesis was implanted, and the extensor mechanism was reconstructed by transfer of the medial gastrocnemius muscle and pes anserinus tendons. All resections had negative margins. There were no local recurrences, but metastases occurred in two patients. Infection was the only major complication and was seen in two patients. The mean postoperative Musculoskeletal Tumor Society score was 61% (range, 36%-100%). The mean postoperative range of flexion was 62 degrees (range, 30 degrees-90 degrees), and the mean extensor lag was 12 degrees (range, 0 degrees-40 degrees). Three patients required a crutch to walk. The functional outcome was poor in the two patients whose proximal tibia was removed with the joint, suggesting that arthrodesis may be best in this situation. In properly selected patients, prosthesis and muscle flap reconstruction provides acceptable function and a good cosmetic result.

Adolescent↗
PubMed2000

[Indications and limitations of surgery of common low back pain].

Surgical treatment of the low-back pain remains controversial in term of efficacy. Surgical treatment is advocated only when conservative management fails, a clearly identifiable cause of lumbar pain is identified, worker's compensations are detected, psychological disorders are treated and disability and pain are still present. In addition, we used a preoperative external diagnostic immobilisation with hip spica cast to select the patients. Posterior instrumented fusion is more often used, however several studies demonstrated the interest of interbody fusion when an inflammatory signal of the disc was detected on the MRI. Spinal fusion provide 50-93% of clinical success in the literature, spondylolisthesis remains the better indication. Only 30% returning to work were obtained.

Discitis↗
PubMed2000

Sensitivity of anulus fibrosus cells to interleukin 1 beta. Comparison with articular chondrocytes.

STUDY DESIGN: Anulus fibrosus cells from rabbits were grown in primary culture 1) to study their ability to produce prostaglandin E2 and Type II phospholipase A2, and to express stromelysin-1 messenger ribonucleic acid; and 2) to study the effect of interleukin 1 beta on this production and on proteoglycan aggregation. OBJECTIVES: To investigate the potency of anulus fibrosus cells to respond to interleukin 1 beta by producing degradative and inflammatory agents as compared with the potency of articular chondrocytes in the same animal. SUMMARY OF BACKGROUND DATA: Interleukin 1 beta has been implicated in the degradation of intervertebral discs. The way anulus fibrosus cells differ from articular chondrocytes in their responses to interleukin 1 beta remains to be established. METHODS: Anulus fibrosus cells and articular chondrocytes were obtained from young rabbits, grown in primary culture, and incubated with interleukin 1 beta. The newly synthesized proteoglycan was measured by labeling with [35S]-sulfate. Proteoglycan aggregation was analyzed by the elution profile on Sepharose 2B columns. The contents of collagen Type II and stromelysin-1 messenger ribonucleic acid were assessed by Northern blot analysis. The Type II phospholipase A2 activity was measured using a fluorometric substrate. Prostaglandin E2 production was evaluated by radioimmunoassay. RESULTS: Anulus fibrosus cells had 2.5-fold less Type II collagen messenger ribonucleic acid than articular chondrocytes, and interleukin 1 beta had no significant effect on this. Anulus fibrosus cells synthesized and secreted four-fold less proteoglycan than articular chondrocytes. Interleukin 1 beta reduced the anulus fibrosus content of total [35S]-sulfated proteoglycan by 35% (P < 0.01), and that of articular cells by 41% and decreased proteoglycan aggregation. Interleukin 1 beta induced the production of stromelysin-1 messenger ribonucleic acid in both cell types. The stromelysin-1 messenger ribonucleic acid content of anulus fibrosus cells was one half that of articular cells. Interleukin 1 beta increased the production of prostaglandin E2 and caused a dose-dependent secretion of Type II phospholipase A2 activity in both cell types. Its effect was 2.5-fold lower in anulus fibrosus cells than in articular chondrocytes. CONCLUSION: Anulus fibrosus cells can be stimulated by interleukin 1 beta to produce factors implicated in local degradative and inflammatory processes. This production is associated with decreased proteoglycan aggregation. Anulus fibrosus cells respond slightly less well to interleukin 1 beta in vitro than do articular cells.

Animals↗
PubMed2000

[Primary leiomyosarcoma of bone. Report of 5 anatomo-clinical cases and review of the literature].

INTRODUCTION: Leiomyosarcoma is a malignant smooth muscle tumor occurring most frequently in uterus or soft tissues and more rarely in bone. MATERIALS AND METHODS: We report the clinicopathologic, immunohistochemical and ultrastructural findings of five cases of primary leiomyosarcoma of bone treated in our Department between 1991 and 1994. The pertinent medical literature is discussed. RESULTS: The tumors were located respectively in the distal tibia (n=2), the distal femur, the sternum and the ilium (n=1). Four lesions were high-grade and one low-grade. All patients (3 women and 2 men) underwent wide surgical resection associated with polychemotherapy in four cases. Two patients died of metastatic disease, two had local recurrence and one is alive with no evidence of disease at the last follow-up. DISCUSSION: Excluding cases which involve the facial skeleton, there are to our knowledge 95 cases of primary leiomyosarcoma of bone reported in the literature. This tumor arises more commonly in adults (mean age: 49 years) with an equal gender distribution and involves predominantly the long bones near the knee. In the majority of cases, plain X-rays exhibit an osteolytic lesion with cortical penetration and indistinct margins. The diagnosis is based on microscopic features demonstrating fusiform tumor cells arranged in interwoven bundles, and the immunohistochemical results of widespread cytoplasmic positivity for smooth muscle actin. The best pronostic parameter is the histologic grade correlated with both the recurrence and metastatic rates as well as the survival rate. Surgery constitutes the main treatment since chemotherapy or radiotherapy did not provide an improved prognosis over a wide resection.

Adult↗
PubMed2000

[Proximal femoral reconstruction with megaprosthesis versus allograft prosthesis composite. A comparative study of functional results, complications and longevity in 41 cases].

PURPOSE OF THE STUDY: To compare femoral reconstruction using megaprosthesis versus allograft prosthesis composite. MATERIAL AND METHODS: Forty-one consecutive proximal femoral reconstructions with an allograft-prosthesis composite (21 cases) or a megaprosthesis (20 cases) after tumor resection were reviewed in a retrospective study. The following criteria were considered: functional outcome; long term survival; complications. Chi-square test and Wilcox tests were used to compare groups. The medium and long-term survival curves for these reconstructions were made using the Kaplan-Meier standard methods. The failure of prosthesis was defined as revision for mechanical failure (either aseptic loosening or dislocation), for infection or local recurrence. The comparison of the curves was performed using the Log-Rank test. RESULTS: Infection (10 p. 100) and instability, in both groups, and loosening, in the megaprosthesis group, were the common causes of failure. There was difference between functional results in the two groups (limping and crutches using was more lower in allograft-prosthesis composite group). Survival analysis showed a 5 and 10-year survival of 77 +/- 12 p. 100 for the patients with composites. Five and ten - year survival were 73 +/- 11 p. 100 and 0 p 100 respectevely for those with megaprostheses. No significant difference was noted between survival of these two groups but a tendancy (p =0.09). Radiological allograft resorption was noted for more than 50 p. 100 of allograft composite prosthesis without modification of functional result or symptomatic loosening. DISCUSSION: The functional results seem better in the composite group when compared to the megaprosthesis group. Reconstruction of the abductor mechanism is essential to stabilize the prosthesis and to decrease the limp. When the great trochanter cannot be preserved, we used suture of gluteus medius tendon to tensor of fascia lata, which is re-enforced using a piece of biceps femoris. The dislocation rate was approximately the same in our two groups. Several authors reported a lower dislocation rate with composite reconstructions than massive prosthesis. The rate of infection is similar to other reported series. In our study it has been possible to show a tendancy for superior survival of the composite reconstruction. When the review was later than 5 years the radiological appearance of the graft in our series was often concerning with resorption or fragmentation present in six of the eight cases. This radiological appearance is not as yet responsible for any revision or any change in the functional result however it does remain a worry. CONCLUSION: Composite reconstructions probably allow a better functional result when considering proximal reconstruction of the femur. The radiological appearance of these allografts in the long term is however worry some without any evidence so far of worsening functional level or any evidence of prosthetic loosening. It would seem to us that the current level of knowledge would advocate the use of massive allografts together with prosthesis. This does seem still to remain the best choice for proximal femoral reconstruction.

Adult↗
PubMed2000

[Bone allografts in orthopedic surgery: current concepts].

In the last decade, indications for bone allografting in orthopedic surgery have progressively increased, related to, on the one part, treatment of benign or malignant tumors, but, on another (major) part, to treatment of major bone defects due to loosening of hip or knee total prostheses. In France, legislation and control concerning donated human tissues, safety precautions, and the uses for human tissues have been greatly modified over the last few years. The authors describe the various obligations implicated by these activities and the consequences for tissue banks and surgeons; They describe different processes for bone inactivation and their action on allograft mechanical properties, or the biological capability for integration to the host bone. The authors then discuss different current techniques for bone stock reconstruction and the results in prosthetic or tumoral surgery, as well as their consequences on current surgical indications. In conclusion, they emphasize the optimal conditions for the success of allografts in orthopedic use: stability of the host bone-graft junction, vitality of the bone support, and a favourable mode of constraint of the graft, which have to be protected by osteosynthesis, but should not, however, miss partial bearing.

Bone Transplantation↗