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P Delincé

Publications and source records attributed to P Delincé.

13 recordsLinked to original sources
PubMed2002

Anatomical and radiological correlation of Lequesne's "false profile".

Lequesne introduced a radiological projection, which is an oblique view of the edge of the acetabulum, to diagnose arthrosis affecting the anterior part of the joint and to measure the anterior coverage of the femoral head. In this study, we attempted to determine the anatomical correlation of his technique. Fifteen in vitro hemipelvises underwent radiography according to Lequesne's description, using metallic markers and wires to mark physical landmarks. According to geometric laws, the points used by Lequesne do not correlate anatomically. Although Lequesne's technique allows a diagnosis of acetabular dysplasia, measurements are on average 5.5 degrees less than those made anatomically.

Acetabulum↗
PubMed2001

[Shock absorption by intermediate hip prostheses].

PURPOSE OF THE STUDY: The bipolar prosthesis was developed in an attempt to alleviate acetabular wear of conventional metallic endoprostheses. The prosthesis was designed to achieve low-friction metal-on-polyethylene inner bearing motion while decreasing shear stress across the acetabular cartilage. Although good clinical results were obtained, the principle of a persistent inner mobility was contested and some authors have assigned the delay of cartilage erosion to the shock absorption capacity of the polyethylene. The present study was focused on assessing the vibration and shock damping effect of metal monoblock and bipolar head prostheses. MATERIAL AND METHODS: The transmission of the shock wave through these two types of prostheses was studied in vitro. The two heads were first tested in a rigid environment to eliminate all external parasite frequencies. The impact excitation was applied with a hammer connected to an oscillometer. A second accelerometer was connected to the prosthesis stem. Shock wave transmission was analyzed. Secondly, the head was tested with a system vibrating in the same order of frequencies as the skeleton, with and without pre-constraint. The frequency response functions were analyzed. RESULTS: For the metallic prosthesis, the frequency of vibration recorded on the femoral stems was in a large frequency range from 0 Hz to 10 KHz. For the bipolar prosthesis, all the high frequencies of the shock wave were eliminated and only shock wave frequencies from 0 to 500 Hz were recorded. In an environmental system vibrating below 100 Hz, the metallic head did not express high frequencies of vibration. The coefficient of shock absorption was not significantly different for the two heads. DISCUSSION: In the first rigid environment, the metallic head did not filter the high frequency components of the shock wave and the bipolar head tended to eliminate high frequency components due to the flattening effect of the impulse load by the polymer. But, the lower leg is not a rigid structure and the musculo-skeletal system vibrates in frequencies below 100 Hz. In similar conditions, the increased shock-absorbing effect of the polyethylene is far more difficult to observe. For the metallic prosthesis, the recorded frequency of vibration also belongs to a small domain of frequency, from 0 Hz to 100 Hz. The range of frequency is similar for the two types of prostheses. CONCLUSION: Even though polyethylene is characterized by a more pronounced damping capacity than metallic materials, in experimental conditions simulating the vibratory characteristics of the human body, the introduction of a high-density polyethylene liner does not afford any additional shock-absorbing effect compared with a metallic head. It cannot explain cartilaginous sparing.

Equipment Failure Analysis↗
PubMed2001

Biomechanical evaluation of Hackethal's intramedullary bundle pin fixation of humeral neck fractures.

Humeral neck fractures can be stabilized using a bundle of intramedullary pins as described by Hackethal. In order to decrease the risk of pin migration, packing of the medullary cavity with as many pins as possible is sometimes recommended, but others believe that stability can be decreased by destruction of cancellous bone in the humeral head by a large bundle of pins. A surgical neck fracture was created with a saw in 30 frozen cadaveric humeri. Bone quality was evaluated by radiography and densitometry. Fractures were stabilized using Hackethal's technique of retrograde intramedullary pinning with varying numbers of 2.5-mm diameter pins; increasing torsion or bending moments of force were then applied to the bones studied. Stability was found to improve with an increasing number of pins and with higher humeral head density. Based upon these findings, the use of a large number of pins is recommended to reduce the risk of pin migration. Up to eight pins, the risk of destruction of cancellous bone in the humeral head appears very low.

Biomechanical Phenomena↗
PubMed2001

Localized pigmented villonodular synovitis of the knee with bone involvement mimicking a benign bone tumor: CT and MR findings.

The localized form of pigmented villonodular synovitis is characterized by a limited involvement of synovium. Although the knee is the joint that is commonly affected, bone changes in this location are not usual. We report the case of a histologically proven localized form of this entity in the knee, which mimicked a benign bone tumor on the basis of an MR pattern, CT findings, and scintigraphic results. Bone changes which may cause a pitfall in the diagnosis of the disorder are discussed.

Adult↗
PubMed1999

[Analysis of the acetabulum anterior cover].

PURPOSE: The false profile X-Ray view as described by Lequesne, allowing the measurement of the anterior cover of the acetabulum, is a slantwise view obtained by a 65 degrees inclination of the pelvis on the radiographic plate. The errors introduced by this radiological measurement of the anterior cover are evaluated. MATERIALS AND METHODS: An anatomical and radiological analysis is conducted on 20 acetabula. The anterior cover is measured on the bone and the A point, the anterior extremity of the acetabular roof, is plumbed. Each pelvis is imaged following the Lequesne method. The VCA angle is measured with the radiological point A described by Lequesne and with the metallic point A as reference. RESULTS: The difference between the anatomical and radiological values of the anterior cover is an average by 11 degrees and undervalues the anatomical value. The deviation is reduced by the application of a trigonometrical formula. A difference between the radiological localisation of A point described by Lequesne and the metallic marker is pointed out. This difference increases when the acetabulum becomes dysplasic. CONCLUSION: The acetabular anterior cover measured with the radiological incidence described by Lequesne undervalues the real value. Moreover, the error increases when the acetabulum is dysplasic.

Acetabulum↗
PubMed1999

A method to measure acetabular cup anteversion after total hip replacement.

The authors propose a simple and practical method to measure radiologically the angle of ante- or retroversion of the acetabular cup using a goniometer. It only necessitates an anteroposterior radiograph centered on the femoral head and another one centered on the public symphysis. Special x ray equipment, compass, conversion table, mathematical formulas, or a pocket calculator are not required. The opening of the prosthetic cup is projected on the film as an ellipse. According to the rules of descriptive geometry, the true size of the angle of anteversion is easily obtained. The geometric constructions consist in drawing four lines. The adequate positioning on a hip radiograph of the protractor, drawn on the goniometer, permits the direct reading of the true and planar anteversion angles of the cup.

Acetabulum↗
PubMed1998

[Study of cotyloid anteversion by coxometric measurement].

A coxometric evaluation is helpful for the diagnosis and the prognosis of hip dysplasia. These measurements also given an intrinsic guide to the surgeon for total hip arthroplasty. A coxometric protractor is drawn on the majority of the goniometers and allows the measurement of the angle of internal and external roof, the angle of the acetabular roof obliquity and the femoral neck-shaft angle on a hip AP X-ray. The purpose of this report is to demonstrate that on the same X-ray, the adequate placement of the coxometric protractor allows to calculate the inclination angle, the acetabular anteversion angles and the anterior roof angle.

Acetabulum↗
PubMed1998

The femoral supracondylar nail: preliminary experience.

The treatment of supracondylar fractures of the femur with an intramedullary nail presents some theoretical advantages. Compared to plate osteosynthesis, intramedullary fixation requires less extensive dissection and is biomechanically more favorable. In the elderly patient, these characteristics seem important since bone quality, extensive procedures and bone grafting remain problematic. Since August 1994 we have treated 16 consecutive closed fractures of the distal femur (A.O. type: 7 A.1, 2 A.3, 4 C.1, and 3 C.2) with the Green-Seligson-Henry intramedullary retrograde supracondylar nail. Twelve elderly and osteoporotic patients had suffered low-energy trauma, three young patients had been involved in a traffic accident and one other young patient had attempted suicide. The operative technique, complications and results are described. All fractures healed within a few months (2 to 7) without bone grafting. No failure of the fixation material and no deep infection were encountered. With most elderly patients the functional result was judged satisfactory, considering the population studied. Intraoperative determination of alignment and avoiding shortening were the major difficulties, especially with long oblique or comminuted fractures. Two major complications were encountered in the young population. In one instance nail protrusion in the intercondylar notch caused a deep patellar cartilage erosion and sympathetic distrophy leading to a 15 degrees flexion deformity. Another young patient needed a quadriceps release at the fracture site and subsequently a femoral valgus osteotomy in order to achieve an acceptable final result. In elderly osteoporotic patients presenting an isolated supracondylar fracture, antegrade nailing remains the "safest" technique by avoiding an unnecessary arthrotomy. When previous hip or knee surgery precludes the use of antegrade nailing techniques or when the fracture extends into the intercondylar region, retrograde supracondylar nailing offers some advantages compared to conservative treatment or plate osteosynthesis. On the other hand in young patients, anatomic reduction and alignment should be the goal, and open reduction with plate osteosynthesis, supplemented by bone grafting if needed, should remain the gold standard. When this seems technically impossible, the antegrade or retrograde insertion of an intramedullary nail with intraoperative assessment of length and fracture alignment is an interesting alternative.

Adult↗
PubMed1976

Direct method for estimating the total gastrin cell number in the stomach of rats.

An original and simple method for counting the total G cell number in the stomach of small rodents is described. Staining the G cells with the peroxidase-antibody technique and counterstaining the nucleus make it possible to correct the nuclear overestimation. Counting directly the total number of G cells in sections from the entire stomach avoids errors due to tissue retraction and to unprecise delineation of the antro-fundic limit.

Animals↗
PubMedDate not supplied

Different aspects of the cyclops lesion following anterior cruciate ligament reconstruction: a multifactorial etiopathogenesis.

After anterior cruciate ligament (ACL) reconstruction using a patellar-tendon autograft, 65 patients underwent second-look arthroscopy in conjunction with hardware removal. In 23 patients, hypertrophic tissue was found in the anterior part of the knee. This tissue presented different aspects, from a well-synovialized nodule to a more disorganized fibrous tissue according to patients' complaints. Endoscopic resection of this offending tissue was generally sufficient to obtain a satisfactory result. In patients presenting a loss of extension, the notch frequently had to be enlarged. We have found a multifactorial pathogenesis to be likely: the nodule is a natural fibroproliferative tissue process originating either from drilling debris from the tibial tunnel or from remnants of the ACL stump and, more rarely, from broken graft fibers. Sometimes, when the graft is malpositioned, the scar tissue can result from repeated graft impingement on the notch at terminal extension. Formation of this aberrant tissue should be prevented by proper positioning of the graft, by enlargement of the narrowed notch in chronic cases, by using drills of increasing diameters to avoid production of osteocartilaginous fragments, by meticulous resection of all drilling debris and ACL remnants around the tibial tunnel, and by enlarging the notch roof if any contact with the graft is present when the knee is fully extended intraoperatively.

Adult↗
PubMedDate not supplied

[Long-term results of the surgical treatment of hiatal hernia using the Boerema technic].

The authors analyse the results of the surgical treatment of "symptomatic hiatus hernia" by the Boerema anterior gastropexy, in 69 patients. As compared to other techniques, the observed mortality and morbidity rates are similar. The postoperative delay is greater than 2 years in 95% of the patients and 83% of them are satisfied with the treatment. Better results are actually obtained with other techniques. Nevertheless, anterior gastropexy which remains the easiest and fastest technique, may still be used in elderly or high risk patients. The Nissen fundoplication is recommended for the majority of the patients suffering from "symptomatic hiatus hernia", especially when ulcerative reflux esophagitis is present.

Adult↗