Hello Dr Rettenmaier,

Thank you for sharing this interesting case. Recurrent pilonidal cysts are challenging indeed. Dr Robinson's has shared his thoughts with me and I'm posting his message on his behalf:
"Recurrent pilonidal cysts can be complicated cases. I usually send them to a colorectal surgeon. We've tried vacs and puraply but rarely worked".
I'm also adding some more insights below:
-The overall recurrence rate of pilonidal disease is around 6.9 percent.[1] Recurrent pilonidal cysts usually occur due to persistent presence of sinus tracts and skin pores (pits), which need to be removed/destroyed. Definitive treatment for these conditions is surgical, with preservation of as much normal tissue as possible to facilitate wound management.[2][3]
-As for type of surgical excision: A study with 171 chronic pilonidal cysts found that recurrence rate was significantly lower with wide surgical excision and delayed (secondary) wound healing.[4]
-As for primary versus secondary closure: Primary closure is associated with faster wound healing, but secondary healing is associated with lower recurrence rate (8.7 versus 5.3 percent).[1]
If patient prefers primary closure due to need to return faster to work for instance, off-midline wounds (1-2 cm lateral to intergluteal cleft) is associated with significantly lower rate of recurrence compared to mid-line. Flaps are recommended for coverage of wide excisions to release tension and decrease complications.[1]

Alternative methods to surgical excision have been developed but not widely used: video-assisted ablation of pilonidal cyst (new technique, needs more research), phenol injections, fibrin glue (weak evidence according to a Cochrane review).[5]

Other advisors may chime in later with more insights. Please let us know if you have any other insights on this case or any other case! Thank you!

[1] : https://www.ncbi.nlm.nih.gov/pubmed?term=20091589
[2]: https://www.ncbi.nlm.nih.gov/pubmed?term=22379405
[3]: https://www.ncbi.nlm.nih.gov/pubmed?term=20109636
[4]:https://www.woundsresearch.com/article/five-year-follow-and-recurrence-rates-following-surgery-acute-and-chronic-pilonidal-disease
[5]:https://www.ncbi.nlm.nih.gov/pubmed?term=28085995

Hi Dr. Rettenmaier, thank you for your question! In addition to the overview Dr. Song has generously provided, I thought I would chime in with some quasi-anecdotal information.

I work for a group of general surgeons, as well as a reconstructive plastics surgeon, and they operate on pilonidal cysts with regularity. The Limberg flap is a popular one, and we have utilized it as primary definitive treatment for complex cysts or as a secondary measure for failed excision with primary closure with recurrence. In cases that are very large or have a challenging body habitus, we have used a myocutaneous V-Y flap.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3726804/

“Literature study showed that Limberg flap reconstruction following rhomboid excision of the sinus area was superior to primary closure [13] and other flap procedures [14] and a safe and reliable method in sacrococcygeal pilonidal sinus disease with low complication and recurrence rates.”