Study of the efficacy of coated Vicryl plus antibacterial suture in an animal model of orthopedic surgery

PURPOSE

To evaluate the efficacy in vitro and in vivo of a new antibacterial suture, polyglactin 910 suture with triclosan, compared with a traditional braided suture, polyglactin (Vicryl), in a validated animal model of orthopedic infection. Our primary goal was to compare the microbiologic effectiveness of the two sutures. The secondary goal was to evaluate histopathologic signs of an inflammatory response.

METHODS

We used 20 Sprague-Dawley rats. Samples of Staphylococcus epidermidis were diluted to a 0.5 McFarland concentration (100,000 colony-forming units/mL). A surgical steel suture was placed in the spinous process of the rats, and the deep zone of the incision was contaminated bilaterally. Wounds were closed with one of the sutures. After 16 days, the animals were sacrificed, and the surgical wounds were reopened, with cultures being performed of both the zone adjacent to the implant and the deep region of the wound. We also studied the histopathologic features of the tissue adjacent to the implant.

RESULTS

No clinical signs of infection were observed. The culture of the zone adjacent to the implant was positive in nine animals in the polyglactin group vs. three in the polyglactin 910 with triclosan group (p = 0.005). Culture of the deep zone of the wound was positive in ten animals in the polyglactin group vs. six in the polyglactin 910 with triclosan group (p = 0.03). We found predominant polymorphonuclear neutrophil populations in four samples in the polyglactin group vs. two in the polyglactin 910 with triclosan group.

CONCLUSIONS

Under simulated conditions of severe intraoperative contamination, the antibacterial suture reduced the number of positive cultures after surgery by 66.6%. Judging from the available clinical information, its use might contribute to reducing the number of infected implants by 25.8%. Human studies are needed to determine the clinical implications of these results.

Bilateral sacroiliac dislocation with intrapelvic intrusion of the lumbosacral spine. A case report

A patient sustained bilateral sacroiliac dislocation in which the proximal part of the sacrum was displaced 10 cm anteriorly and 6 cm inferiorly into the pelvis. Stabilisation was initially obtained with an external fixator. Operation was carried out later: reduction was achieved by overhead skeletal traction using sublaminar wires; two screws were inserted through each sacroiliac joint and the two fragments of the sacrum were wired in place.

Osteochondral allografts for osteochondritis dissecans and osteonecrosis of the femoral condyles

Osteochondral allografts were used in 11 patients with osteochondritis dissecans and 4 with osteonecrosis of the femoral condyles. The lesions were mainly in the medial condyle in 13 cases, and in the weightbearing area in 10. The grafts had a mean size of 6 cm2; 8 were kept in hypothermia at 4 degrees C for less than 24 h and 7 were stored at -80 degrees C with cryoprotection. After an average follow up of 3.2 years, only 2 patients needed a further operation, one for nonunion and the other for a fracture of the graft. The others had improved clinically and showed radiological union of the graft with preservation of the joint space.

Osseous hydatidosis

Nineteen patients with osseous hydatidosis were treated over a period of thirteen years. There were four deaths. Ten patients became asymptomatic. The treatment used was either curetage or resection, often repeatedly, and protracted lavage of the wound with ethacridine. Five patients received a desensitization treatment (hydatin), but the results in these cases were indeterminate as far as the action of the drug was concerned.