Clifford Lawrence1. 1. Department of Dermatology, Royal Victoria Infirmary, Newcastle upon Tyne NE1 4LP, England. c.m.lawrence@ncl.ac.uk
Abstract
BACKGROUND: Digital myxoid cysts (DMCs) are ganglia of the adjacent distal interphalangeal joint (DIPJ) caused by leakage of fluid from the joint into the surrounding tissues. The connection between the DIPJ and the cyst can be identified by the injection of methylene blue into the DIPJ. However, the injection of methylene blue into the DIPJ is difficult and time-consuming. Based on this understanding of the cause of DMCs, we have used a surgical technique to treat DMCs without the need for skin excision. Herein, we have adapted the technique and demonstrated that precise leakage point identification is not required for treatment success, thus reducing the potential postoperative morbidity, reducing the operative time, and simplifying the surgical technique. DESIGN: This was a prospective, open, nonrandomized trial of therapy. A skin flap was designed to include the cyst and tissues from the cyst to the DIPJ. No skin excision was required, and no osteophyte removal was attempted. SETTING: University dermatology department. PATIENTS: Thirty-two consecutive symptomatic subjects with 26 finger DMCs and 6 toe DMCs. No patient had been previously treated. MAIN OUTCOME MEASURES: Clinical assessment postoperatively and recurrence rate after a minimum follow-up of 8 months. RESULTS: Of the 26 finger DMCs, 24 (92.3%) remained healed at 8 months; and of the 6 toe DMCs, 2 (33.3%) remained healed at 8 months. CONCLUSIONS: Digital myxoid cysts are caused by leakage of joint fluid from the DIPJ to the cyst. The leakage point is sealed in the healing process that occurs after a flap is raised and re-sited. The flap must be designed to include the undersurface of the cyst and the tissues between the DIPJ and the cyst. No skin excision or osteophyte removal is required. The procedure is not recommended for DMCs of the toes.
BACKGROUND:Digital myxoid cysts (DMCs) are ganglia of the adjacent distal interphalangeal joint (DIPJ) caused by leakage of fluid from the joint into the surrounding tissues. The connection between the DIPJ and the cyst can be identified by the injection of methylene blue into the DIPJ. However, the injection of methylene blue into the DIPJ is difficult and time-consuming. Based on this understanding of the cause of DMCs, we have used a surgical technique to treat DMCs without the need for skin excision. Herein, we have adapted the technique and demonstrated that precise leakage point identification is not required for treatment success, thus reducing the potential postoperative morbidity, reducing the operative time, and simplifying the surgical technique. DESIGN: This was a prospective, open, nonrandomized trial of therapy. A skin flap was designed to include the cyst and tissues from the cyst to the DIPJ. No skin excision was required, and no osteophyte removal was attempted. SETTING: University dermatology department. PATIENTS: Thirty-two consecutive symptomatic subjects with 26 finger DMCs and 6 toe DMCs. No patient had been previously treated. MAIN OUTCOME MEASURES: Clinical assessment postoperatively and recurrence rate after a minimum follow-up of 8 months. RESULTS: Of the 26 finger DMCs, 24 (92.3%) remained healed at 8 months; and of the 6 toe DMCs, 2 (33.3%) remained healed at 8 months. CONCLUSIONS:Digital myxoid cysts are caused by leakage of joint fluid from the DIPJ to the cyst. The leakage point is sealed in the healing process that occurs after a flap is raised and re-sited. The flap must be designed to include the undersurface of the cyst and the tissues between the DIPJ and the cyst. No skin excision or osteophyte removal is required. The procedure is not recommended for DMCs of the toes.