Percutaneous Zadek Osteotomy and Sural Nerve Proximity: A Cadaveric Anatomical Mapping Study

The Zadek osteotomy, a dorsal closing-wedge procedure of the calcaneus, is commonly used in the surgical treatment of insertional Achilles tendinopathy, particularly in patients unresponsive to conservative measures. Although minimally invasive surgical (MIS) techniques offer potential benefits such as reduced soft tissue trauma and faster recovery, concerns persist regarding the risk of iatrogenic injury to the sural nerve because of limited visualization. This cadaveric study aims to provide a detailed anatomical assessment of the sural nerve and its branches in relation to the entry point of the MIS Zadek osteotomy, with the goal of quantifying their proximity and offering data that may help reduce the risk of nerve injury during the procedure.

Twenty fresh-frozen human lower limb specimens were subjected to a standardized MIS Zadek osteotomy using a 3 × 30-mm Shannon burr. The osteotomy was guided fluoroscopically and performed through a lateral percutaneous approach. Post-procedure, meticulous anatomical dissections were conducted to identify the sural nerve and measure its distance from the anterior and posterior arms of the osteotomy using digital calipers with 0.1-mm precision. Measurements were independently recorded by 2 observers to ensure accuracy.

The sural nerve was successfully identified in all specimens. No instances of sural nerve transection or gross anatomical disruption were observed. The mean distance from the osteotomy to the sural nerve was 11.95 mm, with a range of 8.3 to 15.4 mm and an SD of 2.18 mm. These findings suggest that when performed within the defined anatomical parameters, the MIS Zadek osteotomy maintains a safe distance from the sural nerve.

In our cadaver study, we found that the MIS Zadek osteotomy maintained a mean distance of 11.95 mm from the sural nerve. These findings define anatomical proximity; clinical safety requires prospective validation.

Our study defines a reproducible anatomical margin for MIS Zadek osteotomy; clinical safety needs prospective validation.