Outcomes of a single dose of injection polidocanol application in aneurysmal bone cyst.

Background: Aneurysmal bone cysts are common osteolytic tumours that have ability to expand and produce pathological fractures. Recurrence is a major issue in such tumours posing a treatment dilemma to clinicians. Injection polidocanol has shown promising results, but the number of injections still remains a topic of debate. Methodology: A prospective interventional study done on 13 patients of biopsy-proven aneurysmal bone cysts. Patient related outcome measures(PROM's) seen using VAS score, SF-12 score and ROM of the involved extremity. Radiologically volume of tumour and cortico-medullary ratio were calculated. All patients received single dose of injection polidocanol and were followed up to 6 months. Results: The mean age of patients was 9.5 years, with slight female predominance. Most cases had Campana grade 1. Mean VAS score improved from 9/10 to 1/10, ROM of the proximal and distal joints of the involved bone improved from 60 % (± 20 %) to 100 %. Mean SF12 score increased from 41 (±7): 47 (±3) to 54 (±2): 58 (±2) at the end of 6 months(p < 0.05).Mean volume of the lesion decreased from 6.30 cc (± 1.30) to 2.86 cc (±1.34) (p < 0.0005) with a reduction of MCR from 4.8 (±0.6) to 3.6 (±0.5) on a similar time span (p < 0.0005) at end of 6 months. 2 patients showed recurrence with none of the patients showing any complication. Conclusion: Single dose of Injection Polidocanol for Aneurysmal Bone Cysts is a unique study, not described in literature before. The smaller lesion in initial staging can be treated effectively with single dose of polidocanol reducing morbidity and treatment cost to the patient. It is as good as giving multiple doses of Polidocanol as per as functionality of the limb is concerned.Also, we propose a new parameter "Medullary-cortical ratio", which is an effective way to assess the improvement and resolution of ABC after administration of Polidocanol.