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Frequency, presentation and postintervention prognosis of chondroblastoma.

OBJECTIVE
To evaluate the frequency of clinico-radiological presentation and the prognosis after treatment of chondroblastoma.


DESIGN
A descriptive, observational study.


PLACE AND DURATION OF STUDY
The study was carried out at the Department of Orthopaedic Surgery, JPMC, Karachi over the period of 16 years, January 1986 to June 2002.


METHODOLOGY
Patients in teenage, presenting with signs and symptoms of a primary bone tumours, were included by retrospectively reviewing the tumour registry record. Detailed scrutiny of clinical record was carried out to analyze the clinico-radiological presentation and posttreatment prognosis criteria of healing was symptom-free centripetal and homogeneous ossification.


RESULTS
Seven (1.24%) out of 563 primary bone tumour cases were chondroblastoma. The clinico-radiological presentation in the 2 out of 7 (28.57%) cases was classical, 2 simulated osteomyelitis and other 3 as chondromyxoid fibroma, aneurysmal bone cyst and giant cell tumour. Lesions were treated with curettage and bone grafting. One patient (14.28%) developed recurrence within 2 years after curettage and healed after re-curettage and bone grafting. Five out of 7 (71.42%) tumours showed good response and 2 out of 7 (28.57%) showed satisfactory response.


CONCLUSION
Chondroblastoma is very rare benign primary bone tumour with high local recurrence rate. The lesions confined to epiphysis of weight-bearing bone present early with symptoms of mild arthritis. Lesions in non-weight-bearing bones often present late and simulates epiphysio-metaphyseal tumours. Lesions heals with centripetal healing and need more than 2 years follow-up to achieve recurrence-free healing.