Hello and welcome to HCM,
Overactive parathyroid glands lead to formation of brown tumor in the bones.
Brown tumor are formed due to over activity of bone forming cells.
'Brown tumor' is a misnomer since it is not a tumor and it is a manifestation of metabolic disturbance caused by
hyperparathyroidism.
A couple of investigations are required before diagnosis can be made and management can be done.
An aspiration cytology of the swelling is required and this investigation can differentiate between a
bone tumor and brown tumor caused by
hyperthyroidism.
Thereafter, blood tests for calcium and parathormone also need to be done to assess the function of parathyroid gland.
In case these investigations suggest any abnormality of parathyroid gland, specialized scan for parathyroid will be required to assess whether there is enlargement of all parathyroid glands or enlargement of single parathyroid gland.
You need to consult an orthopedician for these investigations and thus further work up.
Thanks and take care
Dr Shailja Puri