Figure 1

Key procedures of the novel less-invasive surgical approach. The sheep were placed in a supine position (A). with linen sheets onto the abdomen to extend the sterile area (B). Full extension of hip and stifle joints by axially pulling both hindlimbs during wrapping is crucial to later avoid a possible shifting of the drapes during intraoperative joint mobilization (B). Fenestrated linen sheets are used to cover the proximal, lateral and medial borders, leaving open a triangular operative site (C). Following the slightly oblique skin incision (length 4–5 cm) and arthrotomy, exposure of the distal two thirds of the lateral and medial facet of the femoral trochlea is achieved (D). This preserves the oblique medial vastus muscle and the medial patellar retinaculum and retains the patella in a proximal position without the need for its intraoperative surgical luxation (Figure 2). Each femoral condyle (E) as well as the anterior third of each meniscus (E; arrow) can also be safely exposed when applying different degrees of stifle joint flexion. For closure of the capsule, non-absorbable sutures were used (F). The surgical wounds (F) were closed in layers by simple interrupted suture patterns. Finally, aluminium bandage spray was applied (G).