Protection of the innervation of the tensor fasciae latae in hip direct anterior and anterolateral approaches: a cadaver study

Purpose: This study aims to reveal the exact course of the superior gluteal nerve (SGN) branch innervating the tensor fascia lata (TFL) and show how it can be protected in the direct anterior approach (DAA) and anterolateral approach (ALA). Methods: The anterolateral regions of 22 thighs from formalin-fixed cadavers were dissected. 3 anatomical points were determined. Point A, B, C indicates where the SGN enters the gluteus minimus (GMin) fibres, the SGN leaves the gluteal muscles, the SGN enters the TFL, respectively. Measurements were made on 3 separate lines. Results: On the anterior superior iliac spine (ASIS) and the head of the fibula line (Line 1), the horizontal–vertical distances from point B and C to the ASIS were 7.99 ± 3.65 mm–40.40 ± 11.50 mm and 11.74 ± 6.61 mm–70.35 ± 14.11 mm respectively. The horizontal-vertical distances from point A, B, C to the greater trochanter (GT) were 32.41 ± 9.97 mm–55.28 ± 12.25 mm; 67.70 ± 8.54 mm–17.76 ± 13.57 mm; 63.92 ± 9.96 mm–13.00 ± 7.92 mm on the GT and the head of the fibula line (Line 2), respectively. The horizontal-vertical distances from point A, B, C to the GT were 24.58 ± 9.83 mm–42.54 ± 12.86 mm; 9.45 ± 7.92 mm–36.25 ± 9.06 mm; 26.18 ± 11.12 mm–64.05 ± 11.67 mm on the ASIS and the GT line (Line 3). Conclusions: In the DAA, the increased risk of damaging the branch of the SGN that innervates the TFL must be kept in mind. The protection of this branch can be ensured with easy and applicable rules.