The B.A.C.H. system is a new classification for long bone osteomyelitis. It uses the four key inter-disciplinary components of osteomyelitis, namely, bone involvement, anti-microbial options, soft tissue status and host status. This study aims to assess the inter-user reliability of using the B.A.C.H. classification system. We identified 20 patients who had a diagnosis of long bone osteomyelitis using a previously validated composite protocol. For each patient, osteomyelitis history, past-medical history, clinical imaging (including radiology report), photographs of the affected limb and microbiology were presented to clinical observers on an online form. Thirty observers, varying in clinical experience (training grades and consultants, with a variety of exposure to osteomyelitis) and specialty (orthopaedic surgery, infectious diseases and plastic surgery) were asked to rate the twenty cases of osteomyelitis. Before rating, an explanation of how to use the classification system was given to the observers, in a structured ‘user key’. The responses were assessed by accuracy against a reference value and Fleiss' kappa value (Fκ).Aim
Method
We have reviewed the published classifications of long-bone osteomyelitis. This review demonstrated the limitations and poor recognition of existing classifications. We have designed a new system which includes four easily identifiable variables which are Bone involvement, Antimicrobial availability, Soft tissue coverage and Host status. This is called the B.A.C.H. classification system. In this study, we aim to retrospectively validate this classification in a cohort of osteomyelitis cases. We identified 100 patients who had received surgery for osteomyelitis between 2013–2015 in a single specialist centre. Each patient was classified retrospectively by two assessors who were not involved in the initial patient care. Osteomyelitis was confirmed in each patient by a validated composite protocol.Aims
Methods