Minimally Invasive Anatomical Reconstruction of Posteromedial Corner of Knee: A Cadaveric Study

We conducted a study to determine if a minimally invasive posteromedial reconstruction technique would return medial knee stability to its intact state. Ten cadaveric knees were tested under 3 state conditions: intact, sectioned, and reconstructed. The medial compartment opening was measured on valgus stress radiographs at full extension and at 20° of flexion with a 10-N valgus load (applied with dynamometer) to assess valgus stability in the intact, sectioned, and reconstructed states. After posteromedial sectioning, mean medial gap was statistically significantly larger (P = .0002) at full extension (11 mm vs 3.3 mm) and at 20° of flexion (12.6 mm vs 3.7 mm). There was no statistically significant difference between the value of the intact state and the value after minimally invasive reconstruction at 0° (P = .56) or 20° (P = .102) of flexion. Interobserver reliability for the measurements was almost perfect (κ = 0.86). Minimally invasive medial knee reconstruction returns medial knee stability almost to normal at full extension and at 20° of flexion. Development of minimally invasive techniques will allow medial ligament reconstruction with minimal disruption of the surrounding tissue, potentially leading to less scarring and easier restoration of knee motion after surgery.