Does the induced membrane have antibacterial properties? An experimental rat model of a chronic infected nonunion

Abstract

Introduction The Masquelet procedure proved its efficiency in treating infected nonunion filling bony gaps up to 25 cm. Yet the use of local antibiotics is still questionable in the daily practice with lack of evidence regarding its usefulness in controlling infection. An experimental rat model is put in place to study the antibacterial properties of the induced membrane produced during the first stage of Masquelet. Method Twenty-three-month-old wistar male rats are inoculated with a 0.5 mL solution of 10^8 CFU/mL MRSA over a critical fracture done on the right femur. Six weeks later, remaining 11 rats exhibiting signs of a chronic infection with a sinus tract and oozing pus along with radiological nonunion are used for a first stage Masquelet procedure. They are randomly divided into two groups with six rats having no local antibiotic in the cement mixture and five rats having 3 g of vancomycin mixed with gentamycin loaded cement. Six weeks later (twelve weeks from baseline), all eleven rats are euthanized and blood samples for C-reactive protein are withdrawn. The induced membrane is identified and resected along with bone fragments and sent for cultures and pathology. Results MRSA is isolated in the cultures of all six rats in the first group where no local antibiotic was added. Altered polymorphonuclears with abscess and pus are noted on four of six pathology samples. However in the second group where local antibiotics were added, three out of five rats exhibited eradication of MRSA (p = 0.034) and all samples did not exhibit clear infection signs on pathology. A pyo-epithelioid over a foreign body reaction is seen predominantly in this group demonstrating a regenerative process. Discussion The induced membrane does not have antimicrobial properties capable of overcoming an infected nonunion on its own. When local antibiotics were added during the first stage of the Masquelet procedure, new bone formation occurred indicating the need to control an infection in order for bone union to occur. Conclusion Local antibiotics use in adjunction to extensive debridement is advisable during the first stage of a Masquelet procedure for an infected nonunion.

Novel Piston Technique Versus Ilizarov Technique for The Repair of Bone Defect After Lower Limb Infection

“…Removal of the entire bone segment and continuous antibiotic release with bone cement can effectively remove the dead bone and bio lm, and so will offer a better chance of eliminating infection compared with the Ilizarov technology. Though none infection recurrence occurred in presented both groups, Sami Roukoz, et al (40) and Sarita R Shah, et al (41) reported that antibiotic loaded bone cement could achieve a better anti-infectious effect. A narrative review (42) showed the rate of infectious recurrence in patients with infected or noninfected critical-sized tibial bone defects treated by Ilizarov methods was 4.58%.…”

Histological Analysis of Induced Membranes in Patients Whose Bone Defects Were Treated With the Masquelet Technique to Identify Factors Affecting the Vascularity of Induced Membranes

“…Their results can be interpreted to indicate that the addition of antibiotics to the cement does not impair the vascularity of IM. Recently, Roukoz et al have shown that the addition of antibiotics to the cement was effective in controlling infection, and did not alter the membrane's activity in a rat infected nonunion model [21]. Impregnation of antibiotics to the cement spacer is usually performed by the surgeon to treat infection at the rst stage of the Masquelet reconstruction surgery for patients with osteomyelitis or infected nonunion, which is similar to our method.…”

Novel piston technique versus Ilizarov technique for the repair of bone defect after lower limb infection

“…Removal of the entire bone segment and continuous antibiotic release with bone cement can effectively remove the dead bone and biofilm, thus offering a better chance of eliminating infection compared to the Ilizarov technique. Although no infection recurrence was noted in either group, Roukoz et al [ 33 ] and Shah et al [ 34 ] have reported that antibiotic-loaded bone cement can achieve a better anti-infection effect. A narrative review [ 35 ] showed that the rate of infection recurrences in patients with infected or non-infected critical-sized tibial bone defects treated using the Ilizarov method was 4.58%.…”