Desmoplastic fibroma of the ilium

The desmoplastic fibroma is a rare locally invasive bone tumour. Surgical resection with minimal margins is recommended.

A 15 year-old boy was referred with chronic left thigh pain. MRI revealed a bone lesion within the cavity of the inner table of the left iliac wing without invasion of the underlying bone marrow. A surgical biopsy revealed a desmoplastic bone fibroma. A partial resection of the inner table of the iliac wing sparing the outer table was performed. At the latest follow-up the initially spared iliac wing had needed further resection. The reason proposed for this is devascularisation by substantial periosteal stripping causing partial resorption initially, then necrosis and ultimately ulceration through the skin necessitating further surgical resection.

The technique of resection of a pelvic desmoplastic fibroma sparing the outer table of the iliac wing has not previously been reported. The objective of a limited resection was to minimize the risk of a postsurgical limp caused by weakness of the gluteus medius muscle. However we report that this technique did not work in this case. A wider resection of the iliac wing as it is recommended for a malignant tumour would have yielded a similar final outcome.

A partial resection of the iliac wing seemed an appealing technique for a benign tumour of the inner table of the iliac wing. However, considering the complications encountered, the authors advise a simple "en bloc" resection of the iliac wing for this type of tumour in this location.