Labral Graft Volume Augmentation and Femoral Remplissage Have Positive Impact on Hip Distraction Stability After Excessive Cam Resection: An Ovine Model

Purpose To biomechanically assess the effects of femoral remplissage and labral volume augmentation, individually and in combination, on restoring hip distraction stability after excessive cam resection in an ovine model. Methods Forty‐eight fresh‐frozen ovine hips were randomized into 6 groups (n = 8): (1) remplissage, (2) baseline labral reconstruction, (3) combined baseline reconstruction, (4) increased thickness (2×), (5) combined augmented (2× + remplissage), and (6) excessive thickness (4×). A 10% over‐resection defect was created at the anterosuperior head‐neck junction. Autologous tendon grafts were fixed with 2.0 mm titanium anchors. Distraction testing at 90° flexion was performed under a 200 N load at 60 mm/min. Suction seal strength was defined as the peak resistance force (N) during femoral head separation. Two parameters were calculated: Δ 1 (Postop‐Intact) for residual loss and Δ 2 (Postop‐Excised) for stability recovery. Statistical analysis used Kruskal‐Wallis and Bonferroni‐corrected Mann‐Whitney U tests ( P < .003). Results Excessive cam resection significantly reduced suction seal strength ( P < .001). The 4× reconstruction and 2× + remplissage groups achieved the best stability restoration (4×: Δ 1 = 0.78 N, Δ 2 = 24.06 N; 2× + remplissage: Δ 1 = 4.53 N, Δ 2 = 23.12 N; both P < .003 vs baseline). Remplissage alone provided partial recovery, whereas baseline reconstruction had the weakest performance (Δ 1 = 11.48 N, Δ 2 = 14.92 N). Increasing graft thickness improved both Δ 1 and Δ 2 , correlating with greater stability recovery. Conclusions Standard labral reconstruction alone did not fully restore suction seal strength after excessive cam resection. Increasing graft volume improved distractive stability compared with the resected state, and combined 2× labral augmentation with femoral remplissage achieved stability restoration comparable to the 4× reconstruction group. Remplissage alone provided partial recovery but did not consistently restore intact‐level stability. Clinical Relevance These findings suggest that increased graft thickness and femoral remplissage may improve distractive stability in an ex vivo over‐resection model.