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Biomedical subjects

J C Mulier

Publications and source records attributed to J C Mulier.

At least 37 records · Page 2Linked to original sources
PubMed1982

Patellar tendinitis: pathology and results of treatment.

Patellar tendinitis can be considered as an overload lesion in athletes. Anatomical pathology reveals focal degeneration and microtearing at predisposed areas near the insertion of the quadriceps or patellar tendon. Thie prognosis and treatment are dependent on the stage of the affection. A program of conservative treatment is effective in the early stages of the disease but it fails in a high proportion (16/38) of cases in the later stages. Surgery directed towards the tendon, rather than a bony procedure, yielded favourable results in 27 out of 29 patients.

Adolescent↗
PubMed1981

The effect of the combined use of a clean air system and one day prophylactic administration of cefamandole in total hip replacement.

238 patients undergoing primary total hip replacement had on a routine basis both "clean air system" prophylactic conditions and a one day lasting prophylactic Cefamandole treatment on the day of surgery. All patients had a follow-up during at least one year; the follow-up in some patients was up to 25 months. Deep infections were not seen in any of the patients and E.S.R. returned to normal values one year after the intervention in all patients. Superficial wound infections were seen in 2% of the patients. One fifth of the patients had significant bacteriuria on the day of the intervention. This did not seem to have any implication. In our series both laminar air flow and prophylactic administration of Cefamandole on the day of intervention give an adequate prophylactic coverage to prevent the dangerous deep infection as a complication in total hip surgery.

Aged↗
PubMed1981

Fracture hip prostheses due to welding defects.

Two retrieved Moore type hip prostheses of cast Co-Cr-Mo-alloy were examined after metallic failure. The first case concerns a fatigue fracture in the stem of the prosthesis due to an abrupt change in the cross-sectional area and the presence of inappropriate welding beads in the stem. The abrupt change occurring at a transition from an I-beam into a rectangular profile gives rise to stress concentrations thus increasing change of fatigue crack initiation. The second case is a fracture of the hollow head of the prosthesis through a weld. The two parts of the cast femoral head were incompletely welded. Comparison with similar welds in other femoral heads of prostheses of the same type reveals a poor welding uniformity. Hence, both fractures are associated with the welding process. A critical investigation is needed to find optimal welding conditions for Co-Cr-Mo-alloy prostheses.

Biomechanical Phenomena↗
PubMed1981

Anterior subluxation of the lateral tibial plateau. A new clinical test and the morbidity of this type of knee instability.

A new clinical test is presented for the diagnosis of anterolateral knee instability. The advantages of the test are obviation of apprehension- and muscle spasm avoiding false negative results and also the recognition by the patient of his sensation of "collapsing at the knee". This allows for differentiation between "giving away" due to a torn meniscus alone and concomitant anterolateral knee instability. It implies important consequences for prognosis and treatment of the knee problem of the athlete. Underlying pathology consists of a torn anterior cruciate ligament and primary or secondary stretching of the soft tissues at the lateral and posterolateral capsule. These lesions and a positive test for anterolateral knee instability does not inevitably result in a disability for sports activity. The dynamic muscular control protects the knee in many instances from collapsing at cross over cutting.

Diagnosis, Differential↗
PubMed1981

The geometrical properties of human femur and tibia and their importance for the mechanical behaviour of these bone structures.

A series of non pathological human tibial and femoral bones have been tested in torsional loading at high strain rates. Elastic (torsional stiffness) and ultimate properties (Tmax) have been determined. A geometrical description of the individual bone structures has been performed by determination of the polar moment of inertia (assuming axial symmetry), variation of this parameter along the long axis of the bone and length of the specimen between the grips. A fairly accurate prediction of mechanical behaviour of bone structures could be obtained using these geometrical parameters. The high variation of elastic and ultimate properties of whole bone structures in torsional loading is primarily the result of the high variation of polar moment of inertia for the different bone specimens.

Adult↗
PubMed1980

Effect of hydroxyapatite impregnation on skeletal bonding of porous coated implants.

Skeletal fixation of permanent implants by new methods such as fixation by mechanical interlocking of bone with porous prosthetic coatings or chemical bonding with bioactive materials shows growing potential. This paper reports on the resulting skeletal fixation of a combined porous and bioactive material. Metal plugs with a porous metal fiber coating impregnated with hydroxyapatite were implanted for 2, 4, and 12 weeks and were compared to the parent porous, nonbioactive, metal fiber material. Statistical analysis of the interfacial failure shear stress, as obtained by mechanical testing, shows there is a marked influence of hydroxyapatite impregnation on the rate of bone ingrowth and the strength of the interfacial bond the few weeks following surgery. Microscopical examination reveals that the apparent stimulation of bone ingrowth into the surface pores of the implant is the reason for the increased rate of bond formation. The results are of particular clinical interest: with an increased rate of bone ingrowth, weight bearing might be allowed much earlier, thus reducing the recuperation period.

Animals↗
PubMed1980

Out-patient treatment of surgically resistant non-unions by induced pulsing current - clinical results.

The results of treatment by induced pulsing current of 19 cases of non-union, all of which had previously been subjected to surgical procedures in an attempt to correct the non-union are presented. The method used, was developed by A. Bassett at the University of Columbia. Eleven cases proceeded to a definable result; in seven of these functional union occurred. Of the 8 cases still under treatment, 6 show a definite evidence of progress. This method proves to be effective in the treatment of difficult non-unions, which have failed to respond to operative procedures.

Adult↗
PubMed1980

Long term follow-up results of a femoral megaprosthesis. A review of thirteen patients.

A total of 16 patients were treated with a femoral megaprosthesis at the University Hospital of Pellenberg. Their charts were reviewed and 13 patients were seen for a follow-up study. The indications for this procedure were revisions of a total hip arthroplasty and primary bone tumors. The aspects of the operative technique and postoperative management are discussed. A careful reconstruction of the abduction apparatus and a post-operative immobilisation for a period of 3 months seems to be important to prevent post-operative dislocation and to obtain an adequate functional result. The operation seems to be successful regarding the absence of pain and a restored function.

Adult↗
PubMed1980

Operative treatment of adolescent idiopathic scoliosis with follow-up study of the postoperative physical and social status.

The results of 64 posterior fusions for scoliosis are presented. Also the first detection of the curves and the preoperative treatment is discussed. Details are given about the immediate and late postoperative complications and about the correction loss. Interesting too, is an investigation of more subjective information, concerning the postoperative physical and social status. These last problems are not very often discussed in studies of scoliosis.

Adolescent↗
PubMed1980

Skeletal fixation of implants by bone ingrowth into surface pores.

An alternative skeletal fixation by bone ingrowth into porous coatings has been studied. Stainless steel fiber coatings using different fiber diameters (50-100 micrometer) and different pore sizes have been tested. Plugs, intramedullary rods and various types of knee prostheses have been implanted in dogs in non functional and also in functional loading conditions. Histological and mechanical evaluation of the bone implant interface has been performed. Consistent bone ingrowth was observed for implants in non functional conditions if the pore size exceeded 70 micrometer. Ingrowth in functional loading conditions requires rigid initial stability of the implant and intimate contact of implantcoating and surrounding bone tissue.

Animals↗
PubMed1980

Triple arthrodesis and Lambrinudi arthrodesis. Literature review and follow-up study.

A literature review is presented about triple arthrodesis and Lambrinudi arthrodesis including indications, techniques, complications, and a more extensive review of some specific indications. Forty-eight patients were operated on between 1961 and 1977, 25 of whom were reviewed at follow-up. Our follow-up study shows a rather high rate of pseudarthrosis, with however a normal failure rate. According to these findings transfixation of the bones with K-wires is to be considered.

Adolescent↗
PubMed1979

Short term bonding behaviour of bioglass coatings on metal substrate.

Bioglass specimens were implanted in 11 dogs for periods ranging between two and twelve weeks in order to study the short term bonding behaviour of bioglass coated on metal. Metal fibre porous coated specimens without bone growth inducive microlayer were implanted as controls. The conclusions reached pertain to the validity of push out test results, bioglass short term bonding and the effect of the dipping procedure to coat bioglass on metal: 1. It is impossible to compare the bonding effectiveness of bonding materials tested under slightly differing circumstances, and a fortiori at different laboratories, 2. there is no sufficient evidence to establish a difference in bone bonding strength with regard to trabecular bone of bioglass and metal fibre porous coated specimens at 2 and 4 weeks; at 12 weeks, however, a higher interfacial failure shear strength is obtained with the control porous specimens, 3. bone bonding may be hampered by compositional differences arising as a result of the processing of a bioglass on metal coating. Technologically it is, however, possible to exclude this problem.

Animals↗
PubMed1979

Clinical study on internal fixation of femoral neck fractures.

A clinical study on the results of internal fixation of femoral neck fractures treated by multiple Knowles pinning was undertaken and correlated with the results of an experimental study. Experimentally, failures were produced by downwards migration of the Knowles pins. This phenomenon accounts for the settling of the femoral head on the neck and the frequency of non-union or malunion in patients with subcapital fractures. The type of fracture, type of reduction and age correlate with failure rate. This has to be explained by biomechanical considerations based upon the mode of failure of the internal fixation. A Garden stage III and IV, a varus or anatomical reduction of the fracture and an old age predispose to failure of the internal fixation and consequent non-union.

Age Factors↗
PubMed1979

Experimental study on internal fixation of femoral neck fractures.

The relative strength and the failure mode of internal fixation by multiple pinning and nailing was investigated on 35 specimens. Internal fixation consisted of 3, 5 and 7 Knowles pins, a Smith-Petersen nail or a sliding nail plate. The strength of a specimen with a triflanged nail is only half of that with multiple Knowles pins. There is no significant difference in strength of 3, 5, or 7 pin specimens. The strength of an internal fixation with a sliding nail plate is not superior to the strength of multiple pinning. The mode of failure for the different types of internal fixation is primarily a crush fracture of the supporting trabecular bone at the femoral neck with downward and outward migration of the pins or nail. Except with the fixation with 3 pins where an initial bending could be observed, failure is not a plastic deformation of the internal fixation device.

Bone Nails↗
PubMed1978

In vitro cultivation of human tumor tissues. II. Morphological and virological characterization of three cell lines.

Nineteen human tumors, mostly of sarcomatous nature, were cultured in vitro. Three cell lines were isolated and further characterized: MG-57 derived from a giant cell tumor, MG-63 derived from an osteosarcoma and MG-72 derived from a xanthohistiocytoma. The cell lines varied in morphology and growth pattern. An abnormal karyotype with marker chromosomes was present in Mg-63 and MG-72. None of the cell lines spontaneously produced detectable C-type virus particles. Stimulation with IUDR and dexamethasone also failed to induce detectable particle release.

Animals↗