A 23-year-old male patient applied to the orthopedic outpatient clinic with complaints of right foot swelling and pain without a trauma history. Physical examination revealed swelling and pain with palpation at the third metatarsal dorsal level of the right foot (Figure 1). The patient was examined by foot computed tomography (CT) and contrast magnetic resonance imaging (MRI) for detailed imaging upon detecting an expansive lesion in the third metatarsal bone, revealing the expansive lesion of 37 x 23 x 20 mm in size and with a sclerotic wall with multiple septa (Figure 2). Thereupon, sclerotherapy treatment was percutaneously applied with 10 ml of polidocanol to the lesion. The patient re-applied to the orthopedics outpatient clinic 6 months later because of the metatarsal growth and was examined with MRI. Lesion dimensions were measured as 63 x 45 x 36 mm in MRI and significant dimensional progression was detected in the lesion compared to the previous MRI (Figure 3). Hence, the operation was decided, and a ray amputation was performed on the third metatarsal bone and phalanx. An aneurysmal bone cyst (ABC) was diagnosed based on the histopathological examination (Figure 4).
An ABC is a lytic and benign lesion that is located in the metaphysis of long bones, causing cortical enlargement and containing trabeculations.1,2 The literature reported ABC in the metatarsal bone in a few cases, and lesions of this region are extremely rare.3,4 Intralesional curettage or, in some cases, en-block resection methods are used for ABC treatment. Different adjuvant treatments are used in ABC to minimize postoperative local recurrence. Percutaneous techniques have been included in the treatment protocol with good results using fibrosing injection agents.4
Local recurrence has been reported in an ulnar ABC lesion treated with polidocanol in the literature.5 The development of local recurrence can be suggested that intralesional bleeding may have developed during the application of sclerotherapy to the size increase.
In this case, we see that progression has developed in lesion sizes after percutaneous sclerotherapy applied with polidocanol as the primary treatment for the detected ABC in the metatarsal bone. Local recurrence after polidocanol-based percutaneous sclerotherapy of the metatarsal ABC is rarely present.