Aims

The aim of this study was to determine whether the sequential application of povidone iodine-alcohol (PVI) followed by chlorhexidine gluconate-alcohol (CHG) would reduce surgical wound contamination to a greater extent than PVI applied twice in patients undergoing spinal surgery.

Introduction

Fractures of the distal radius are one of the most common extremity fractures encountered in A&E departments and general adult fracture clinics. Over the last 10 years the rate of operation for distal radial fractures has been steadily increasing. Staff within our unit felt that formal teaching, particularly of new medical staff, with regards to fracture reduction and appropriate cast application could result in a reduction in operation rates.

Background: Prader-Willi syndrome is associated with multiple musculoskeletal manifestations including scoliosis, joint laxity, hip dyplasia and lower limb deformity. Scoliosis is reported in almost half of patients with Prader-Willi; however, only a small proportion ever have surgery. The literature suggests that surgery in this group of patients is often difficult. Obesity and apnea cause anaesthetic concern. The surgical procedure is reported as being complicated by excessive intra-operative blood loss, and difficulty with instrumentation; possibly as a result of osteopenia, is described.

Purpose: To compare the experience of scoliosis surgery in Prader-Willi patients in our institution with that previously reported in the literature.

Methods: The notes and x-rays of 6 patients with Prader-Willi syndrome who had corrective scoliosis were reviewed.

Results: Six patients (4 female and 2male) underwent corrective scoliosis surgery. The mean age at which scoliosis was detected in the patients was 5 years (range 2–7years). The mean Cobb angle at time of initial referral was 30° (range 8°–86°). Indication for surgery in all cases was curve progression. The mean age at time of surgery was 11.8 years (range 10–13years). The mean pre-operative Cobb angle was 70° (range 40°–90°) and mean post-operative Cobb angle was 23° (range 10°–40°). Three patients had posterior surgery with instrumentation, one had anterior instrumentation only and two patients had combined anterior release with posterior instrumentation. The most proximal instrumentation levels ranged from T2–T6 and the most distal instrumentation levels ranged from T11-L5. Three patients had all pedicle screw fixation, 2 had hybrid fixation (with screws at curve apex) and one had anterior all screw fixation. The mean operative time was 335 mins (range 190–540 mins) and the mean blood loss was 29% of total blood volume (range 14–55%). Standard anaesthetic technique was used in each case and all patients were extubated immediately after surgery. Patients were discharged on average 8 days post surgery (range 6–14 days). One patient had a wound infection and a stitch granuloma requiring surgical debridement and one patient required trimming of proximal end of rod because it was prominent.

Conclusion: Scoliosis surgery in patients with Prader-Willi offers adequate deformity correction and in our experience is not associated with operative technical difficulty, major complications or a prolonged hospital stay.

Recent work has demonstrated that intra-operative contamination of spinal surgical wounds is relatively common. The most frequently isolated wound contaminants are Propionibacterium spp. and coagulase negative Staphylococcus spp. The aim of this study is to examine the efficacy of prophylactic antibiotics used for spinal surgery against bacterial contaminants isolated from intra-operative samples retrieved during spinal surgical procedures.

Intra-operative wound samples were taken from 94 patients undergoing spinal surgery. Samples including skin, subcutaneous tissue and wound washings were processed, inoculated onto agar and incubated under both aerobic and anaerobic conditions for a period of 2 weeks. Bacterial growth was identified using commercially available biochemical test galleries. Thirty-six bacterial isolates were identified. The predominant bacteria isolated included Propionibacterium spp. (n=21) and coagulase negative Staphylococcus spp. (n=15). Each bacterial isolate was tested for its susceptibility to antibiotics used as antimicrobial prophylaxis during spinal surgery. Antibiotic sensitivities were determined in accordance with National Committee for Clinical Laboratory Standards (NCCLS) guidelines.

The antibiotic that performed best against Staphylococcus spp. isolated was ciprofloxacin with 93% of isolates being susceptible to this antibiotic. Cefamandole and cefuroxime also performed well against Staphylococcus spp. isolates.

The antibiotic that performed best against Propioni-bacterium spp. isolates was cefamandole with 100% of isolates being susceptible. Cefuroxime and ciprofloxacin also performed well. The antibiotic that performed least well against bacterial isolates was erythromycin with only 76% of Propionibacterium spp. and 47% of Staphylococcus spp. exhibiting susceptibility.

The results of this study demonstrate that ciprofloxacin, cefuroxime and cefamandole are effective against the majority of Propionibacterium spp. and Staphylococcus spp. isolated from within the spinal wound during surgery. The use of erythromycin in the penicillin allergic patient is questioned and ciprofloxacin proposed as a possible alternative.

The first aim of the study was to investigate if bacteria were implicated in non-union of fractures of the tibia and femur, which had been treated with intramedullary nailing. The second aim was to evaluate the antimicrobial susceptibility of bacteria isolated from the retrieved intramedullary nails.

Forty intramedullary nails removed from tibial and femoral fractures were retrieved for the purpose of the study. Twenty of these nails were from fractures, which had successfully united and 20 were removed from fractures which had failed to unite prior to further operative intervention. There was no evidence of clinical infection in either of the two groups. The nails were subjected to ultrasound in the research laboratory to dislodge adherent bacteria formed as biofilm from the surface of the nail. Using both standard culture techniques and non-culture techniques (Immunofluorescence microscopy and PCR analysis) any dislodged bacteria were isolated and identified.

Isolated bacteria were tested for antimicrobial susceptibility to commonly used antibiotics in orthopaedic practice according to NCCLS guidelines.

Bacteria were detected in 15 out of 20 [75%] of the nails removed from fractures, which had developed a non-union, and in 5 out of 20 [25%] of fractures that had united, using both standard culture techniques and non-culture techniques. The bacterial isolates identified were mainly Staphylococcus epidermidis and the Gram-positive anaerobe Proprionibacterium acnes.

Vancomycin was the most effective antibiotic, with 2 out of 34 [6%] isolates being resistant. Erythromycin was the least effective, with 21 out of 34 [62%] isolates being resistant. Based on overall Minimum Bactericidal Concentrations at which 90% of all strains were killed, Vancomycin was the most active bactericidal agent tested followed in decreasing order by fucidic acid, ciprofloxacin, gentamicin, cefamandole and erythromycin.

Bacteria were detected more commonly in the fracture non-union group than in the union group [p< 0.01]. Of the antibiotic agents tested Vancomycin was the most effective and Erythromycin was the least effective.