Development of in vitro biocompatibility assays for surgical material.

This work reports the development of a test to evaluate the biologic effects of implant material used in orthopaedics and traumatology based on the examination of inflammation and allergic reactions at the cellular level. The variation in arachidonic acid metabolite production by murine peritoneal macrophage cultures was studied using different powders of implant material. Macrophage activation by zymosan served as a control. Mouse peritoneal macrophages were labeled with 14C-arachidonic acid, and the synthesis of cyclooxygenase products (6-keto-prostaglandin F1 alpha; prostaglandins F2 alpha, E2, D2; and thromboxane B2) and lipoxygenase products (hydroxyeicosatetraenoic acids) was analyzed and quantified by chromatography. Results obtained through these assays support the reported clinical data that chrome and nickel increase the production of hydroxyeicosatetraenoic acids by mouse peritoneal macrophages. HXPATRI, titan oxide, and monoclinic zircon also increase the production of hydroxyeicosatetraenoic acids in contrast to other powders tested (alumina, HXPBL, chrome cobalt alloy, stainless steel 316L, titan, quadratic zircon), which have little effect on the production of arachidonic acid metabolites by the lipoxygenase pathway. It is concluded that determination of arachidonic acid metabolite production by murine peritoneal macrophage cultures is appropriate for evaluating implant material.

Blood-brain barrier permeability, cerebral edema, and neurologic function after closed head injury in rats.

We previously described the time course of changes in neurologic status (as indicated by neurologic severity score [NSS]) and cerebral edema (as indicated by brain tissue specific gravity and water content) after closed head trauma in rats. The present study was designed to determine whether head trauma alters the integrity of the blood-brain barrier (BBB), the role of the BBB in edema formation and neurologic outcome, and the effect of MK-801 (a noncompetitive N-methyl-D-aspartate receptor antagonist) on BBB permeability. Rats in which cranial impact was delivered during ether anesthesia (n = 106) were killed at 15 min, 1, 2, 4, 10, and 24 h, and 2, 4, and 7 days. Control rats (n = 12) received no cranial impact. Subsets of head-injured rats killed at 4 and 24 h received MK-801 (3 mg/kg intraperitoneally) 1 h after injury. BBB permeability was assessed with intravenous injection of Evans Blue dye, cerebral edema was assessed by determining brain tissue specific gravity and water content, and neurologic status was assessed using NSS. Tissue extravasation of Evans Blue was maximal in the injured hemisphere 4 h after injury, but a residual BBB permeability defect was still evident as long as 4 days after the insult. In MK-801-treated rats, extravasation of Evans Blue in the injured hemisphere was not significantly different from that in the noninjured hemisphere.(ABSTRACT TRUNCATED AT 250 WORDS)

[Epidermoid carcinoma arising in femoral osteitis. A case]. / Carcinome épidermoïde sur ostéite du fémur: un cas.

The authors report a case of malignant degeneration arising from a fistula in a patient with chronic osteomyelitis of the femur. This rare complication (0.2 per cent-1.6 per cent) most frequently involves the lower limb. A review of the literature reveals that it is associated with long-standing osteomyelitis (30 years), is most frequently a squamous cell carcinoma or rarely a sarcoma, and is principally treated by surgical amputation. The frequency of metastatic spread is low (30 per cent). Malignant degeneration appears to be a local phenomenon, and if diagnosed early, has a rather favorable outcome following complete excision.

[Paralysis of the radial nerve and supracondylar fractures of the humerus in children. A study of a series of 11 cases]. / Paralysie du nerf radial et fractures supracondyliennes de l'humérus chez l'enfant. Etude d'une série de 11 cas.

Eleven radial nerve paralyses, associated with supracondylar fractures of the humerus in children, are reported: 2 incomplete motor, 5 complete motor, 2 complete motor and partial sensory and 2 complete motor and total sensory. The palsy was noticed before any treatment in 8 cases. In the 3 other cases, the palsy was secondary to difficult and repetitive closed reduction manoeuvers. The fractures were all of the extension type, grade III in 2 cases and IV in 9 cases. The displacement of the distal fragment was posterior and medial in 8 cases. Initial treatment of the fracture was conservative in 5 cases with 2 failures and surgical in 6 cases. Nerve function recovery always followed the same sequence: extensor muscles of the wrist, then extensor muscles of the fingers and at last, extensor muscles of the thumb. Time required for full recovery varied from 4 to 6 months. Open reduction and nerve control did not seem to be better than closed reduction with regard to the required time for neurological recovery and its quality. The indications depend on the extension of the paralysis. If radial palsy is incomplete, the first therapeutic step is closed reduction, followed by surgical reduction if not possible. A primary surgical approach is proposed in cases of complete sensory and motor paralysis because of the operative findings of contusion and incarceration of the nerve which may be aggravated by blind manoeuvers.

[Infection of an open fracture caused by Aeromonas hydrophila. A case report]. / L'infection des fractures ouvertes par Aeromonas hydrophila. A propos d'un cas.

With regard to a case report and the review of literature the authors point out that this uncommon but severe infection due to an aero-anaerobia bacteria, existing preferentially in stagnant or running water. This seriousness leads to the use of appropriate antibiotics instead of those usually prescribed in compound fractures, and most of the time, to the use of irrigation-stucking drainage of the wounds.