Hello, I'm Dr. Jaeho Cho, Director of The Line Plastic Surgery.
Does thigh liposuction leave scars behind the knee?
When treating the entire thigh or calf, incisions are typically needed near the inner knee and ankle to give the cannula enough angle of access. The problem is that these areas are easily exposed when wearing shorts, skirts, or swimwear, and I often hear from patients during consultations who are concerned about visible scarring in these spots.
To get straight to the point: recent research shows that using a longer, bent cannula can reduce the number of incisions and reposition them. At The Line, we also use long cannulas up to 100cm in length and specialized 2mm micro-cannulas depending on the situation, which follows the same underlying principle. That said, this is still an early-stage case study, and it's worth noting that it may not apply equally to every clinic or every body area.
Why does a longer, bent cannula reduce the number of incisions?
Liposuction can only be performed within the range the cannula can reach. With a short cannula, covering the entire leg requires multiple incision points — at the knee, ankle, and elsewhere — to access different areas.
With a longer cannula that is slightly bent, however, a much wider area can be reached from a single incision point. Think of it like cleaning a room: with a short stick, you'd need to reposition yourself at multiple spots to reach every corner, but a longer, bendable stick lets you cover more ground from one position. This principle makes it possible to consolidate incision points into the bikini line, where they're hidden by clothing.
Does this actually reduce scarring?
A case study published in December 2025 by the Department of Plastic Surgery at Peking Union Medical College Hospital in China addresses this question[1]. Traditionally, circumferential thigh and calf liposuction required incisions at the knee and ankle. In this study, a custom-made long, bent cannula — the "bent cannula" technique — was used to reduce incisions to just three, all placed within the bikini line (one at the pubic area, two along the gluteal fold on each side)[1].
The study followed 40 patients (average age 25.9) treated by the same surgeon between January 2020 and December 2022, with a follow-up period of 12 to 39 months[1]. No serious complications were reported during this period, and both the surgeon and patients reported satisfaction with the long-term results[1].
It's worth noting that this study is a case series of 40 patients from a single hospital and a single surgeon, not a randomized controlled trial. The results are also limited to the thigh and calf area, and whether they apply equally to other body areas requires further confirmation.
Individual variation and things to keep in mind
Incision placement and number can vary depending on the treatment area, fat distribution, and skin condition, and bikini-line-only incisions may not be sufficient in every case.
Longer cannulas may require greater surgical skill to handle, meaning the surgeon's experience can affect the outcome.
The study above is a case series of 40 patients; validation through larger, randomized comparative studies has not yet been conducted.
The final position and number of scars can vary depending on body type, treatment area, and individual anatomical structure, so an individual consultation is needed to confirm specifics.
Three key takeaways
1. Using a longer, bent cannula allows a wider area to be reached from a single incision point, reducing the total number of incisions needed.
2. A recently published case study (40 patients) reported that this approach consolidated thigh and calf incisions into three bikini-line locations, with no serious complications and good satisfaction.
3. That said, this remains an early-stage case study, and incision placement can vary depending on the treatment area and individual condition.
Incision placement and cannula selection can vary depending on the treatment area and individual condition. Please consult in person for an accurate assessment.
By Dr. Jaeho Cho (PhD in Surgery)
--- Sources
1. "Bent Cannula" Liposuction Technique Using Only 3 Incisions in Asian Lower Limb Shaping. Plast Reconstr Surg Glob Open. 2025 Dec. PMC 12711367
This article summarizes questions around liposuction incision placement and scarring based on research published on PubMed. Please consult a specialist to confirm your individual condition and surgical plan.