Chondromyxoid fibromas (CMFs) are rare tumours that comprise less than 2% of benign bone tumours; approximately 5-7.9% occur in the ribs. We report a 28-year-old female patient with CMF in the 4th rib that presented to a tertiary care hospital in Muscat, Oman, in 2023. She complained of pain in the right posterior chest wall for 6 months. A chest computed tomography showed posterior 4th rib expansile lesion measuring 3×2 cm without soft tissue involvement. A percutaneous biopsy suggested a diagnosis of chondomyxoid fibroma. The tumour was resected with a free-margin and assistance of video-assisted thoracic surgery approach. The diagnosis of CMF was confirmed postoperatively by histopathological studies. In terms of radiological feature, histopathological findings, and the treatment options, this data and the data of 11 other cases can contribute to guide the advancement of clinical decisions.

Case: A 20-year-old man carried a 33-cm diaphyseal femoral defect after childhood osteosarcoma and three failed reconstructions — distraction osteogenesis, autografting and the induced-membrane (Masquelet) technique. As a final limb-salvage attempt, a patient-specific 3D-printed polycaprolactone–tricalcium phosphate (PCL-TCP) scaffold was implanted over an intramedullary nail and bioactivated with iliac-crest bone marrow aspirate, followed at nine months by reamer-irrigator-aspirator autograft. Biopsy at that second procedure confirmed new osteoid and thick-walled vessels at the scaffold interface, yet radiographic consolidation never followed. Four weeks later Staphylococcus haemolyticus infection supervened, and after serial debridement the scaffold was explanted. At four years the limb is preserved and the patient walks independently with a mild limp and a radiographically fused knee. Conclusion: Histological osteogenesis without radiographic union indicates a construct that was biologically alive but biologically outpaced. Three determinants — a defect roughly twice the length at which scaffold-guided regeneration has succeeded, a scarred and hypovascular host bed, and a staged bioactivation protocol whose repeated open re-entries were themselves the infective exposure — argue that defect length, host vascularity and cumulative infection risk, rather than scaffold chemistry alone, should govern candidate selection for this technology.