Journal of Clinical Orthopedics and Trauma. 2019

Abstract

Purpose

The Response of ganglion cysts to Intralesional steroids is variable. They may disappear completely to never recur again. Others may disappear for some period or show no response to the treatment. We wanted to analyse the response with the help of ultrasound. We also tried to search for the factors responsible for the unpredictable outcome.

Methods

A single centre prospective cohort study was conducted. Ganglion cysts located near the wrist and the ankle region of the limbs were included in the study. Overall 40 patients were followed for 6 months. The ultrasound was used to measure the volume which was measured at zero & sixth month.

Results

Volume of the cysts reduced to more than half in 45% of the participants. Complete disappearance was seen in only 10%.

Conclusion

Aspiration and steroid injection reduces the volume of the cyst. The effect wanes off progressively over a period of time. Majority will have a smaller cyst at sixth month at the same site. It may work better in the smaller cysts.

Summary

There are a variety of available treatment options for ganglion cysts. It is benign so watchful waiting is a strategy, there are also more invasive options including aspiration and radical excision. Combining aspiration with steroid injection is widely practiced but its efficacy is controversial, in the past reported 80% success rates but that has been challenged. This Single center prospective clinical cohort study conducted from march 2017-july 2018 evaluated 40 patients over 6 months aimed to use ultrasound to determine the effectiveness of aspiration with steroid injection and to identify factors associated with unfavorable outcomes. The researchers used ultrasound to observe the response of intralesional triamcinolone on the volume of the cyst. Contents were aspirated then replaced with 1ml of 40 mg triamcinolone. If cyst <0.5 ml then 0.5 ml injected. Average volume reduced by 45%, 42% in hand region and 48% in foot and ankle. Short term results of steroid injection were very satisfying, 75% reduced to less than half size at 1 month. Reduction was not uniform for everyone, only 45% of patients had more than 50% reduction in volume by 6 months, these were termed as “responders”. Residual cysts were present in majority of cases, in only 10% (4 patients) the cyst resolved completely. For the remaining 55% the cysts regained more than half their pretreatment volume (nonresponders). Swelling reappeared in <1 month in 25% of cases (10 patients). Swelling reappeared >1 month in 30% (12 patients). In 5% (2 patients) the size increased after treatment.

Pretreatment volume of the cyst significantly affected the outcome. 71% (10/14) of cysts <0.5 ml responded to treatment, larger cysts had 31% success (8/26). Overall 20% (8/40) were septated, this did not significantly affect outcome. Duration of cysts, right or left side, foot or wrist did not affect outcome. Hypopigmentation of overlying skin was only significant complication observed, seen in 30% (12 patients). No intervention was required.

Intralesional steroid injection is a safe procedure however it may not significantly reduce the volume of cysts in all patients compared to aspiration alone. Smaller cysts <0.5 ml responded significantly better. The authors concluded that even though small cysts reduced significantly initially, the benefit is not permanent however since the procedure is simple and almost harmless it is appropriate as first line management. Only radical surgery is effective in reducing recurrence, some have reported 99% cure rates however it is associated with 20% complication rate and the procedure can be costly, cause financial burden due to missed work, and presence of scar reduces patient satisfaction

Study limited by small sample size at a single center, lack of controls, and authors admitted possibility of selection bias. Strengths include the use of ultrasound as an objective way to measure the cyst, previous studies used more subjective measurement methods such as patient satisfaction, calipers, or measuring amount aspirated (this is less accurate than ultrasound because all the fluid can’t always be aspirated).