A Cadaveric Study of the Plantar Fascia for the In-Step Plantar Fasciotomy

Abstract

The in-step plantar fasciotomy has remained a viable option for treatment of plantar fasciitis. The level of the in-step procedure has previously been described as 1.5 cm distal to the anterior heel fat pad. The authors are unaware of any study defining mean width and thickness of the plantar fascia at specific distances from its insertion. The authors performed a standardized cadaveric dissection of 25 fresh frozen cadaveric specimens from a local region in Pennsylvania. Each fascial band width and thickness of the plantar fascia was measured at the fascial insertion, 2 cm distal from insertion, and 3 cm distal from insertion. The mean (± standard deviation) width of the medial, central, and lateral band of the plantar fascia 3 cm from its insertion was 25.3 ± 5.3, 25 ± 3.41, and 23.3 ± 4.49 mm, respectively. At the same anatomic distance, the band thicknesses were 1.5 ± 0.82, 3.3 ± 0.85, and 1.9 ± 0.33 mm, respectively. The literature describes 2 techniques. The first is transecting between one-third to two-thirds of the plantar fascia during a fasciotomy from medial to lateral. The second is identifying, isolating, and releasing the central band. Our study allows to further quantify this, equating to 24.5 to 49 mm in total medial to lateral transection at 3 cm distal from insertion and an isolated central band equating to 25 ± 3.41 mm. With quantitative measurements of transection length, the surgeon will avoid having to estimate and potentially overtransect. This may help in preventing postoperative sequela related to overcorrection.