There are numerous possible causes of painless masses in the hand and wrist – the majority of them are benign. The most common of these masses include cysts, boney overgrowth, or cartilage overgrowths.
On the wrists, ganglion cysts are the most common type of masses. These are benign collections of fluid that collect as out pouchings of joint lining or tendon sheaths. Ganglion cysts are idiopathic – meaning that there is no definitive cause and most form spontaneously. These cysts are benign and drainage or surgical excision is undertaken typically to relieve discomfort, pain, or for cosmetic reasons.
Another possible cause of a wrist mass is a giant cell synovioma which is a benign tumor of the tendon sheath. They are typically painless but are often surgically because of their predilectionof eroding into adjacent bone.
Boney or cartilaginous overgrowths such as bone bosses or enchondromas can also present as masses on the wrist. A boney boss is simply a benign overgrowth of bone and enchondromas are benign overgrowths of cartilage inside bone. These lesions are exceedingly rare but most of them are benign and usually do not require any surgical intervention.
It is difficult to diagnose a wrist mass without a proper physical examination, associated imaging such as MRIs, or a biopsy of the mass. As a small percentage of wrist masses are cancerous, your mass should be examined by your primary care physician to help determine the exact cause of the mass and ruling out any possibility of malignancy.