CT-guided percutaneous radiofrequency ablation in osteoid osteoma: re-assessments of results with optimized technique and possible pain patterns in mid-term follow-up.

PURPOSE

To re-assess radiofrequency ablation (RFA) of osteoid osteoma (OO) with an optimized technique and to evaluate patterns of post-interventional pain important for the detection of recurrence.

MATERIALS AND METHODS

44 consecutive patients with OO treated with precise inclusion criteria by RFA were examined retrospectively. RFA was performed with an optimized technique. Technical success (TS), primary and secondary clinical success (PCS/SCS) and minor and major complications (MIC/MAC) were evaluated. Pain patterns defined as "osteoid osteoma-specific pain" (OOSP) and "unspecific pain" (UP), "limitations in daily activity" (LDA) and "patient satisfaction" (PS) were evaluated using a numeric rating scale (0 - 10; 0 = no pain, 0 = no limitation, 10 = fully satisfied). The pain intensity before and after RFA was compared. The mean follow-up time was 35 months (n = 40, range 2 - 60 months).

RESULTS

TS was 100 % (n = 44), PCS 98 % (n = 44), and SCS 100 % (n = 40). MIC and MAC were 0 % (n = 44). OOSP was 0 after RFA in all 44 patients. UP was 0 in 24 of 40 patients (60 %), 1 in 11 patients (28 %) for up to 7 days and 1 - 4 in 5 patients (13 %) for 30 - 180 days. LDA was 0 in 39 of 40 patients (98 %), and 1 in 1 patient. PS was 10 in all patients. The pain after RFA was significantly less than before RFA (p < 0.0001).

CONCLUSION

Using an optimized technique primary clinical success rates in the high nineties have to be expected. Unspecific pain of low intensity is not unusual after RFA and has to be distinguished from pain caused by recurrent disease.