中壢高正雄骨科復健診所

Mucoid cyst

This term refers to a tumefaction which appears at the extremity of the fingers, above the nail and develops either rapidly or progressively over several years. 
It is a cyst which is synovial in nature, with its origin at the last finger joint and it is often caused by the early stages of arthrosis.

Deformation may be observed in the nail and is caused by compression of the cyst on the matrice unguéale.

The mucoid cyst is naturally benign, but can be harmful in terms of the compression or the  risk of infection it represents in presence of spontaneous ruptures.

1.DIAGNOSIS :

Diagnosis is made on examination. An X-ray may be requested in order to evaluate the extent of the associated arthrosis

2.TREATMENT :

- In cases with a cyst that is limited in volume, and not causing pain or unguéale deformation, treatment is not always necessary.
- In cases with a larger cyst, with translucent skin which may burst and thus lead to infection in the joint, or in cases with nail deformation, a surgical excision is the recommended treatment.

3.SURGICAL PROCEDURE :

-Length of hospital stay: outpatient 
-Anaesthetic:  regional (only the arm is put to sleep)

The cyst is completely removed by means of a short incision and the altered cartilage at the joint may be abraded to reduce friction. The over-fine skin of the cyst will be removed and possibly replaced by a flap, i.e. skin taken from a nearby site. 

4.AFTER-SURGERY CARE :

Splint on the last 2 phalanges for ten to fifteen days after surgery.  Dressings are to be changed every 2 days.

5.COMPLICATION :

Infection is always possible, but not very frequent 
Recurrence is also always possible in 5 to 10 % of cases. 
A moderate loss of mobility may also be observed in the last joint. 
Algoneurodystrophy : may develop as with all operations and include extensive swelling, stiffness and pain that can last several months.
It is not possible to predict its occurrence or the stiffness left as an after effect and pain is therefore a possibility.