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Biomedical subjects

F Canovas

Publications and source records attributed to F Canovas.

At least 37 records · Page 2Linked to original sources
PubMed1998

Biometry of the capsular ligaments of the wrist.

The aim of our study was to measure the length, width and inclination in the coronal plane of the capsular ligaments, and to express these measurements as a ratio in order to determine the correlation between these parameters and the bone index. The capsular ligaments were studied from 15 cadaveric upper limbs. We identified 11 volar and 2 dorsal intracapsular ligaments. For each ligament, we measured the length to its middle and to its proximal and distal edge, the width at its average portion, and the inclination in the frontal plane. There was a difference between the proximal or distal length and the middle length for four ligaments. In these cases, however, there was a significant correlation between the proximal or distal length and the middle length. The length of capitate, the length of the third metacarpal bone, and the carpal height were significantly correlated with four ligaments. There were correlations between the length of one ligament and that of all others. There was no correlation between the inclination of the radius and the inclination of ligaments in the coronal plane. Nevertheless, there were six significant correlations between the inclination of one ligament and that of all others.

Aged↗
PubMed1998

Interleukin-4 and interleukin-10 are chondroprotective and decrease mononuclear cell recruitment in human rheumatoid synovium in vivo.

We used the severe combined immunodeficient (SCID) mouse model to assess the effect of interleukin-4 (IL-4) or IL-10 injection on cartilage degradation and mononuclear cell (MNC) recruitment to human rheumatoid synovium in vivo. Human rheumatoid synovium and cartilage from five rheumatoid arthritis patients, obtained after joint replacement surgery, were engrafted subcutaneously to 6-8-week-old SCID CB17 mice. Synovial tissues were injected with recombinant human IL-4 (rhIL-4, 100 ng; rhIL-10, 100 ng), both cytokines, or tumour necrosis factor-alpha (TNF-alpha) (1000 U), or phosphate-buffered saline twice a week for 4 weeks. The graft was removed and immunochemical analysis was carried out to assess intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin expression. Moreover, cartilage degradation was assessed through the quantification of the erosion surface on a computerized image of the engrafted cartilage at high power view. MNC recruitment in the synovial tissue was determined by labelling blood MNC with indium-111 before their intraperitoneal injection. The activity obtained in the region of the graft were determined with a gamma camera 72 hr postinjection. The results are expressed as a percentage of initial injected activity. After 4 weeks we observed a decrease of cartilage area in controls (77 +/- 8%), inhibited after injection of IL-4, IL-10, or both cytokines (90 +/- 3%, 89.1 +/- 4%, 89.2 +/- 5% respectively), and 57 +/- 17% after TNF-alpha injection. The % MNC activity in the graft decreased to 77 +/- 81% (NS), 9 +/- 4% (P < 0.003) and 19 +/- 6% (P < 0.007) compared with untreated synovial tissue after treatment with IL-4, IL-10, or both cytokines, respectively. Moreover, IL-10 but not IL-4 decreased the expression of ICAM-1 but not VCAM-1 or E-selectin by synovial cells. These results suggest that IL-10 and IL-4 could have chondroprotective properties, and that IL-10 but not IL-4 inhibits MNC traffic towards the synovial tissue efficiently.

Animals↗
PubMed1998

Tophaceous gout of the navicular bone as a cause of medial inflammatory tumor of the foot.

A case of tophaceous gout of the navicular bone in a 24-year-old woman is reported. Emphasis is placed on the conditions that might have been precipitating, i.e., anorexia nervosa and alcoholism, and the mechanisms by which increased uric acid level may be explained. The main radiographic patterns of tophaceous gout of the foot are recalled to avoid unnecessary surgery in future cases.

Adult↗
PubMed1998

[Apropos of a case of epidermoid carcinoma of the nail bed with intraneural metastasis to the median nerve].

The authors report a case of squamous cell carcinoma of the nail bed with multiple metastases including a metastasis of the median nerve. This particular site raises the problem of the mechanism of dissemination and the aggressiveness of this squamous cell carcinoma of the nail bed contrasts with the data reported in the literature. The initial treatment of this tumour must consist of amputation of the distal phalanx.

Amputation, Surgical↗
PubMed1998

[Radiographic analysis of the orientation of the distal articular surface of the first metatarsal in the horizontal plane].

PURPOSE OF THE STUDY: The lateral obliquity of the distal metatarsal articular surface is a predominant anatomical factor in hallux valgus pathology. It is important to know its normal angular value. MATERIAL-METHODS: The study included 105 feet without any pathology (48 females and 57 males; 53 left and 52 right between 15 and 72 year old). Weight-bearing, anteroposterior X-rays of the foot was made. We measured the distal metatarsal articular angulation (DMAA), the intermetatarsal angle, the metatarsophalangeal angle, the obliquity of the metatarsocuneiform joint and the length of the first and second metatarsal, and the length of the hallux. RESULTS: The main value of the DMAA was 5.78 degrees in our study, 6.79 degrees for women and 4.92 degrees for men. There was no difference between left and right side, no correlation between intermetatarsal angle and DMAA, neither between biometrics parameters and DMAA. DISCUSSION: Our results confirm the Richardson study on cadaver with a main value of 6 degrees for the DMAA. The DMAA value increases in women and it does not increase proportionaly to the intermetatarsal angle; it increases with the value of the metatarsophalangeal angle. All these points have to be taken in consideration in hallux valgus evaluation. CONCLUSION: The distal metatarsal articular surface has a lateral obliquity of 5.78 degrees. It must be evaluated before surgical correction of hallux valgus, in order to decrease recurrence rate of this pathology and iatrogenic deformity.

Adolescent↗
PubMed1997

[Surgical treatment of rheumatoid polyarthritis].

Surgical treatment of rheumatoid arthritis aims to suppress pain, correct deformities, and restore function. This treatment should be adapted to each patient on the basis of clinical and radiographic criteria, with priority given to surgical treatment of the lower limbs. In the early stages, conservative surgery is called for (tenosynovectomy, joint synovectomy) and in later stages, palliative surgery (arthrodesis, prosthesis).

Adult↗
PubMed1997

The relationships of the bile duct and the retroduodenal arteries and their importance in the surgical treatment of hemorrhagic duodenal ulcer.

The anatomic relationships of the gastroduodenal artery (GDA) and the posterior superior pancreaticoduodenal artery (PSPD) with the bile duct in their retroduodenal courses were studied in 35 bloc specimens from normal cadavers, injected after removal. The distances between the GDA, the pylorus, and the bile duct were measured in the sagittal plane. The origin and course of the PSPD in relation to the bile duct were studied. The relation of the GDA and the bile duct were divisable into four types: in Type 1 (n = 22) the two structures separated progressively, the artery being on the left of the bile ducts; in Type 2: (n = 7) the structures approached each other without crossing, Type 3: (n = 5) the GDA crossed in front of the bile duct at the level of the first part of the duodenum (D1), Type 4: (n = 1) the GDA crossed the bile duct below D1 and ran along its right border. The PSPD originated at the posterior face of D1 in 20% of cases (n = 7) and crossed the anterior surface of the bile duct at the posterior surface of D1. In four cases there was no pancreatic tissue between the PSPD and the bile ducs. It follows that the risk of injury to the bile duct when securing hemostasis by transfixing a bleeding duodenal ulcer in the D1 segment is great when the arterial structures (GDA and PSPD) cross the bile duct. This risk is increased when there is no pancreatic tissue between them.

Arteries↗
PubMed1997

Carpal bone maturation during childhood and adolescence: assessment by quantitative computed tomography. Preliminary results.

The aim of our study was to measure the volume of each carpal bone during childhood and adolescence by image processing from computed tomography (CT) scans, and to analyze the relationship between the eight carpal bones. Thirteen CT scans were performed in nine normal prepubertal, peripubertal and post-pubertal children, six boys and three girls, aged 5-14 years. Each scan was processed in order to extract the carpal bones. The volume was computed for each bone. There was a significant correlation between carpal bone volume and age (0.55 < r < 0.79), and a very strong correlation between the volume of a given carpal bone and the volume of all the others, whatever the age (0.87 < r < 0.99, p < 0.01). Image processing is a potentially useful method for assessing bone maturation. The constant ratio between carpal bone volumes indicates that these bones interact with each other in wrist bone maturation.

Adolescent↗
PubMed1996

Circular arterial supply of the pisiform bone.

The arterial vascularization of the pisiform bone was studied from 15 cadavers to assess the possibility of pedicled pisiform transfer in Kienböck's disease. The arterial vascularization of the pisiform bone comes from three pedicles: an upper pedicle arising from the dorsal carpal artery, a lateral pedicle arising from the ulnar artery, and a lower pedicle arising from the deep palmar branch of the ulnar artery. The pisiform bone is well vascularized and, whatever the distribution of the pedicles within the bone itself, we always found an arterial circle around it. The lengths of the upper and lower pedicles expressed as ratios of the length or width of the pisiform bone were variable, as indicated by the coefficient of variation that was greater than 36%. There was no significant correlation between the length of the upper or lower pedicle and the length or width of the pisiform bone. The length of the upper pedicle, which was greater than the distance between the origin of the dorsal carpal artery and the center of the lunate, allows a pedicled pisiform transfer in Kienböck's disease. Nevertheless, it is difficult to assert definitively that the upper pedicle is sufficient to avoid a partial necrosis of the pedicled pisiform bone.

Aged↗
PubMed1996

In vivo migration of tonsil lymphocytes in rheumatoid synovial tissue engrafted in SCID mice: involvement of LFA-1.

Integrin-adressin binding is a critical step in lymphocte attachment to target tissues. The mucosal recognition systems (alpha E beta 7, alpha 4 beta 7, MADcam-1) have been implicated in the autoimmune process in rheumatoid arthritis. We developed a model for in vivo study of radio-labelled lymphocyte circulation and their attachment to human rheumatoid synovium. We studied the homing of tonsil lymphocytes, considered as mucosal lymphocytes, and the involvement of alpha E beta 7 integrin and LFA1 in the homing of tonsil lymphocytes. We engrafted human rheumatoid synovium subcutaneously in 6 week old SCID CB17 mice. Three weeks later, we injected intraperitoneally 20 IO6 human peripheral blood or tonsil mononuclear cells, previously labelled with 3 mCFi HMPAO-99mTc. A mouse total body scintigram was obtained 20 h postinjection. The same protocol was performed after treatment of the MNC and mAb against LFA-1 (CD11a) or alpha E beta 7 (CD103). Tonsil MNC retention in the rheumatoid synovial graft 20 h post-injection was enhanced compared to blood MNC (12731 +/- 8297cpm/200 pixel) versus 5982 +/- 4713cpm/200 pixel, p < 0.05). A monoclonal antibody against LFA 1 decreased the activity in the graft (4152 +/- 1287 cpm/200 pixel), p < 0.05. No significant difference in tonsil MNC attachment to rheumatoid synovial tissue was observed with a mAb against alpha E beta 7 (8057 +/- 5009 cpm/200 pixel). Our results showed an increase in radiolabelled mucosal MNC migration in synovial tissue engrafted in SCID mice compared with blood MNC. Moreover, the date suggest that LFA-1 but not the alpha E beta 7 integrin is involved in tonsil MNC binding to synovial tissue in RA.

Animals↗
PubMed1996

In vivo migration of radiolabelled lymphocytes in rheumatoid synovial tissue engrafted in SCID mice: implication of beta 2 and beta 7-integrin.

OBJECTIVE: Integrin-adressin binding is a critical step in lymphocyte attachment to target tissues. The lymphocyte function associated antigen (LFA-1)/intercellular adhesion molecule-1 (ICAM-1) pathway has been shown to be involved in the homing of lymphocytes to arthritic joints in animal models. The mucosal recognition system [alpha E beta 7/E-cadherin, alpha 4 beta 7/mucosal vascular adressin cellular adhesion molecule 1 (MADCAM-1)] has been implicated in the autoimmune process of nonobese diabetic mice and in rheumatoid arthritis (RA). We developed a model for in vivo study of radiolabelled lymphocyte circulation and attachment to human engrafted rheumatoid synovium, and studied the involvement of LFA-1 and alpha E beta 7 integrin. METHODS: We engrafted human RA or osteoarthritis (OA) synovium subcutaneously in 6-week-old SCID/CB17 mice. Three weeks later, we injected intraperitoneally 20 x 10(6) human peripheral blood lymphocytes (PBL) labelled with 3 mCi 99mtechnetium hexamethyl propylenamine oxime. A mouse total body scintigraphy was obtained 20 h postinjection. The same protocol was performed after pretreatment of the PBL with monoclonal antibodies (Mab) against CD11a (25-3) or against alpha E beta 7 human mucosyl lymphocyte marker 1. RESULTS: PBL migrated in the rheumatoid synovial graft 20 h postinjection (activity in the region of interest of the graft: 7699 +/- 4383 cpm/200 pixel or 4.43 +/- 2.65% of initial activity) versus OA engrafted synovial tissue (1453 +/- 1137 or 0.74 +/- 0.6% of initial activity), p = 0.007. The homing to the engrafted rheumatoid synovial tissue of PBL from healthy subjects was not significantly different from the migration of PBL from patients with RA. A Mab against alpha E beta 7 significantly decreased lymphocyte attachment to rheumatoid synovial tissue (3094 +/- 3808 cpm/200 pixel or 2.65 +/- 2.4% of injected activity), p < 0.03. The same results were obtained with Mab against CD11a (5007 +/- 4190 cpm/200 pixel or 2.27 +/- 1.2%), p < 0.01. Our results show increased blood lymphocytes homing to rheumatoid synovial tissue engrafted in SCID mice versus OA tissue. CONCLUSION: The data suggest that both LFA-1 and mucosal recognition integrin alpha E beta 7 are involved in lymphocyte binding to target tissues in RA.

Animals↗
PubMed1996

Mononuclear cell retention in rheumatoid synovial tissue engrafted in severe combined immunodeficient (SCID) mice is up-regulated by tumour necrosis factor-alpha (TNF-alpha) and mediated through intercellular adhesion molecule-1 (ICAM-1).

The aim of this study was to assess regulation of mononuclear cell (MNC) traffic to human synovial tissue by TNF-alpha and IL-1 and the involvement of ICAM-1 in MNC retention in rheumatoid synovial tissue. Human rheumatoid arthritis synovium was engrafted subcutaneously in 6-8 week-old SCID/CB17 mice. Three weeks later, we injected 20 x 10(6) human peripheral blood mononuclear cells (PBMC) previously labelled with 111indium intraperitoneally into mice containing control or cytokine-injected grafts. Total body scintigraphy was performed 72 h postinjection. The graft was removed and immunochemical analysis carried out to assess ICAM-1, vascular cell adhesion molecule-1 (VCAM-1) and E-selectin expression. In some experiments, mice were treated intravenously with 500 micrograms MoAb anti-ICAM-1 (BIRR-1) or an isotype-matched control MoAb before introduction of MNC. TNF-alpha, but not IL-1 alpha, enhanced MNC retention in the rheumatoid synovial graft 72 h post-injection (graft activity 989 +/- 1227 ct/min per 200 pixels or 3.36 +/- 4.16% of initial injected activity versus 411 +/- 157 ct/min per 200 pixels or 1.13 +/- 0.45% in controls; P < 0.03). TNF-alpha enhanced ICAM-1 expression by synovial cells and endothelial cells, whereas VCAM-1 or E-selectin expression was not enhanced on either cell type. After MoAb treatment of ICAM-1, synovial lymphocyte recruitment of TNF-alpha-treated mice decreased significantly to levels below that of control mice (160 +/- 97 ct/min per 200 pixels, 0.54 +/- 0.33%; P < 0.01). Mononuclear cell retention in rheumatoid synovial tissue engrafted into SCID mice was up-regulated by TNF-alpha and blocked by MoAb to ICAM-1. These results suggest that ICAM-1 is involved in mononuclear cell retention in rheumatoid synovium.

Animals↗
PubMed1996

The superficial peroneal nerve at the foot. Organisation, surgical applications.

The authors report the results of the dissection of the superficial peroneal nerves of 30 adult cadavers, from its emergence through the deep sural fascia up to its terminal branches. Its emergence was located, on average, 11 cm from the lower end of the lateral malleolus (min: 9 cm, max: 11.5 cm). The division of the nerve into the medial dorsal cutaneous n. and the intermediate dorsal cutaneous n. was found in 29 cases after its emergence from the sural fascia and before its passage on the proximal edge of the extensor retinaculum. The distance between the medial dorsal cutaneous n. and the medial malleolus was more than 2 cm. This nerve divided into three branches at a level varying from 5 to 20 cm in relation to the first interdigital space (average 9 cm). The intermediate dorsal cutaneous n. was found in 27 cases. It divided into two branches at a variable distance from the fourth interdigital space (4 to 6 cm). According to Kosinski's classification, we found 24 cases of type I (80%), three cases of type II (10%) and three cases of type IV (10%). The authors stress the numerous topographic variations and the multiple anatomical types.

Aged↗
PubMed1994

Methotrexate concentrations in synovial membrane and trabecular and cortical bone in rheumatoid arthritis patients.

OBJECTIVE: To determine methotrexate (MTX) concentrations in the synovial membrane (SM) and cortical and trabecular bone of rheumatoid arthritis (RA) patients. METHODS: Ten RA patients (9 women, 1 man; mean +/- SD age 49.2 +/- 10.6, mean disease duration 13.2 +/- 9.9 years) undergoing surgical procedures for rheumatoid articular lesions participated in this study. Mean +/- SD MTX treatment duration was 26.4 +/- 21.3 months. The day preceding surgery, 10 mg of MTX was administered intramuscularly. During surgery, a mean +/- SD of 19.7 +/- 2.6 hours after MTX administration, SM, bone fragments, and blood were collected simultaneously. MTX was assayed by fluorescence polarization immunoassay in plasma and tissues. RESULTS: The mean +/- SD plasma concentration was 0.0252 +/- 0.01 nmoles/ml at the time of tissue sampling. The mean MTX concentration in SM was 0.285 +/- 0.159 nmoles/gm. The mean MTX concentrations in trabecular and cortical bone were 0.292 +/- 0.164 and 0.286 +/- 0.126 nmoles/gm, respectively. CONCLUSION: After intramuscular administration, high MTX concentrations are found in SM and cortical and trabecular bone of RA patients.

Adult↗
PubMed1993

[Tenosynovectomy of the flexors in rheumatoid polyarthritis. Analytic study of short term and long term mobility of the fingers].

Between 1970 and 1988, 115 patients with rheumatoid arthritis underwent flexor tenosynovectomy. Fifty patients were reviewed (64 hands). The diagnosis of flexor tenosynovitis remains a clinical diagnosis. Three main groups can be distinguished: isolated carpal tenosynovitis (20%), palmodigital tenosynovitis (50%), diffuse tenosynovitis (30%). Standard surgical techniques were used, particularly in terms of the incisions. All patients underwent rehabilitation in the same rehabilitation centre. The authors analyse their results by comparing overall preoperative and postoperative mobility of the fingers (TAM: Total Active Motion, TPM: Total Passive Motion) and the angular gain in each joint (MCP, PIP, DIP). They report the results obtained at 4 months to eliminate the bias related to progression of the disease. The long-term results (8 years of follow-up) are also analysed. Statistical analysis compares two groups depending on whether flexor tenosynovectomy was isolated (44%) or combined with a dorsal surgical procedure at the same operation (extensor synovectomy, articular synovectomy, stabilisation-realignment of the dorsal aspect of the wrist, resection of the ulnar head) (56%). Ninety percent of patients declared themselves to be subjectively improved. Objectively, mobility was always improved at 4 months then deteriorated to return to its preoperative level at 8 years. Only three patients were reoperated for recurrence. Flexor tenosynovectomy in rheumatoid arthritis is an excellent operation. Its analgesic effect is maintained in time and, when performed early, it appears to protect the patient from the risk of subsequent tendon rupture.

Adult↗
PubMed1993

Influence of methotrexate on the frequency of postoperative infectious complications in patients with rheumatoid arthritis.

OBJECTIVE: To evaluate the influence of methotrexate (MTX) on the frequency of postoperative complications in patients with rheumatoid arthritis (RA). METHODS: We conducted a randomized unblinded prospective study in 64 patients with RA treated with MTX and who underwent orthopedic surgery. Two groups of patients were constituted: in Group A (32 patients), MTX was interrupted 7 days before the surgery; in Group B (32 patients), MTX was not discontinued. RESULTS: Fifty surgical procedures were performed in Group A and 39 procedures in Group B. No postoperative infection was observed in any group. A prolonged wound healing was noticed in 6 cases in Group A and in 4 cases in Group B (not significant). CONCLUSION: We suggest that the interruption of MTX is not required in patients with RA when an orthopedic surgical treatment is planned. However a large prospective study is needed to make a definitive conclusion.

Adult↗
PubMed1991

[Role of scapho-trapezo-trapezoidal arthrodesis in the treatment of Kienbock disease. 11 cases].

11 patients with Decoulx stage III Kienböck's disease with rotatory subluxation of the scaphoid were treated with scapho-trapezo-trapezoid arthrodesis. The associated procedures were lunate implant resection arthroplasty in 6 cases, lunate resection in 3 cases, shortening of the radius in 1 case. The average follow-up was 40 months (12 to 84 months). There was no complication of the arthrodesis. Relief of pain is satisfactory in 7 of the 11 patients. The average grip strength is 66% of that observed on the affected side. The range of movement was decreased especially for radial deviation. There was a positive correlation between, the exact scaphoid reduction, a wrist without preoperative degenerative arthritis and the good clinical results. No differences were observed in the results between the associated lunate procedures. STT fusion seems to be a useful procedure in the treatment of stage III Kienböck's disease with carpal malalignment as it removes compressive stress from the diseased lunate and treats, the accompanying rotatory subluxation of the scaphoid.

Adult↗