The treatment of infected exposed implants which have been used for internal fixation usually involves debridement and removal of the implant. This can result in an unstable fracture or spinal column. Muscle flaps may be used to salvage these implants since they provide soft-tissue cover and fresh vascularity. However, there have been few reports concerning their use and these have concentrated on the eradication of the infection and successful soft-tissue cover as the endpoint. There is no information on the factors which may influence the successful salvage of the implant using muscle flaps.

We studied the results and factors affecting outcome in nine pedicled muscle flaps used in the treatment of exposed metal internal fixation with salvage of the implant as the primary endpoint. This was achieved in four cases. Factors predicting success were age < 30 years, the absence of comorbid conditions and a favourable microbiological profile. The growth of multiple organisms, a history of smoking and the presence of methicillin-resistant Staphylococcus aureus on wound cultures indicated a poor outcome. The use of antibiotic beads, vacuum-assisted closure and dressing, the surgical site, the type of flap performed and the time from primary surgery to flap cover were not predictive of outcome.

Introduction: The natural history of idiopathic scoliosis is not well understood. Previous reports focused on characteristics of curve progression pre-defined at 5–6 degrees. However, the absolute curve magnitude at skeletal maturity is more predictive of long-term curve behavior rather than progression of defined magnitude over shorter periods of growth. It is generally agreed that curves < 30 degrees are unlikely to progress after skeletal maturity. Hence, defining factors that influence curve progression to an absolute magnitude of ≥30 degrees at skeletal maturity significantly aids clinical decision-making.

Methods: Of 279 patients with idiopathic scoliosis detected by school screening of 72,699 adolescents, 186 fulfilled the study criteria and were followed up to skeletal maturity. Initial age, gender, pubertal status and initial curve magnitude were used as predictive factors for curve progression to ≥30 degrees at skeletal maturity. Uni and multivariate, logistic regression and receiver operating characteristic (ROC) analysis was performed.

Results: Curve magnitude at first presentation was the most important predictive factor for curve progression to ≥30 degrees at skeletal maturity. An initial curve of 25 degrees had the best ROC of 0.8 with a positive predictive value of 68% and a negative predictive value of 92% for progression to ≥30 degrees at skeletal maturity. The highest risk was a pre-pubertal female < 12 years of age with a Cobb of ≥25 degrees at presentation; with an 82% chance of progression to a Cobb of ≥30 degrees. Probability of progression to ≥30 degrees was defined by 1/(1 + exp (−z)). [z = −3.709 + 0.931(Gender) + 0.825(Puberty) + 3.314(Cobb) + 0.171(Age)].

Conclusions: Initial curve magnitude is the most important independent predictor of long-term curve progression past skeletal maturity. An initial Cobb of 25 degrees is an important threshold. Combined with other factors, we identify patient profiles with high or low risk for progression.

Early operative debridement is a major determinant of mortality in necrotizing fasciitis. However, early recognition is difficult. The aim of our study is to develop a novel scoring system for distinguishing necrotizing fascitis from other soft tissue infections based on routine laboratory findings on admission.

The developmental cohort consisted of 89 consecutive patients with necrotizing fasciitis treated between January 1997 and August 2002. Control patients (n=225) were randomly selected from patients admitted with the diagnosis of cellulitis or abscesses during the same period. Their haematological and biochemical results done on admission were analyzed.

Total white cell count, haemoglobin, sodium, glucose, creatinine and C-reactive protein were selected as predictors. The final constructed model was reliable and discriminated well between patients with necrotizing fascitis from those with other benign soft tissue infections (Area under the receiver-operating characteristic (ROC) curve, 0.98). The LRINEC score was derived from this model and was validated in a separate cohort of patients from a different hospital (56 patients with necrotizing fasciitis and 84 control patients). Based on the calculated probability we stratified patients with soft tissue infections into 3 risks categories: high (LRINEC score _8), intermediate (LRINEC score 6–7) and low (LRINEC score _ 5) risks groups.

The LRINEC score is a robust score capable of detecting even clinically early cases of necrotizing fasciitis. On admission, patients in the intermediate and especially the high risks groups should be subjected to a frozen section biopsy or MRI scans with an aim of early diagnosis, debridement and ultimately

Staphylococcus aureus is the bacterial pathogen which is responsible for approximately 80% of all cases of human osteomyelitis. It can invade and remain within osteoblasts. The fate of intracellular Staph. aureus after the death of the osteoblast has not been documented.

We exposed human osteoblasts to Staph. aureus. After infection, the osteoblasts were either lysed with Triton X-100 or trypsinised. The bacteria released from both the trypsinised and lysed osteoblasts were cultured and counted. Colonies of the recovered bacteria were then introduced to additional cultures of human osteoblasts.

The number of intracellular Staph. aureus recovered from the two techniques was equivalent. Staph. aureus recovered from time zero and 24 hours after infection, followed by lysis/trypsinisation, were capable of invading a second culture of human osteoblasts.

Our findings indicate that dead or dying osteoblasts are capable of releasing viable Staph. aureus and that Staph. aureus released from dying or dead osteoblasts is capable of reinfecting human osteoblasts in culture.