Photo by YN 08-09
Figure skaters soar and float above the ice, spinning and delighting us with their skill and acrobatics. Skaters spend hours on the ice, and subject their ankles and feet to great stress. When their skates do not fit perfectly, the soft tissues of the foot and ankle can become irritated.
In this case, a 25 year-old female figure skater presented to her orthopedic surgeon complaining of a painful mass over the medial malleolus of her tibia. The physical examination confirmed the presence of a mass along with extensive local soft tissue edema, and she was sent for an MRI for further evaluation.
An axial T2 fatsat image identifies an oval, mass (red arrows) immediately superficial to the medial malleolus (yellow arrow):
A coronal T2 fatsat image again identifies the mass (red arrows) and the medial malleolus (yellow arrow), and also depicts the extensive soft tissue edema (white arrows):
An axial postcontrast T1 fatsat image shows that the majority of the mass fails to enhance. There is thin, circumferential enhancement of the lesion:
Based on these images, a diagnosis of medial malleolar bursitis was made. Brown et al. (AJR 2005, 184:979-983) described the appearance of the medial malleolar fat in an asymptomatic population and described the MRI appearance of the medial malleolar bursa. They described ten patients with medial malleolar bursitis (six figure skaters and four ice hockey players).
The medial malleolar bursa is an adventitial bursa. It develops as a consequence of abnormal, extended pressure over the medial malleolus of the tibia. An adventitial bursa is a reactive bursa that forms as a result of chronic soft tissue irritation. Unlike a true bursa, an adventitial bursa lacks a true epithelial lining. In the foot and ankle, adventitial bursae are most common in the forefoot, typically occurring under the first and fifth metatarsophalangeal joints. They can also be found medial or dorsal to the first metatarsal head, and superficial to the medial malleolus, as in this case.
Medial malleolar bursitis is usually treated nonsurgically, with activity modification, anti-inflammatory medications, and topical treatment. If the patient's symptoms do not resolve over a prolonged period of time, surgical resection of inflamed bursa may be necessary. This injury may be prevented by wearing properly fitted skates, using extra padding, and avoiding overtraining.