Semimembranosus Tendon Advancement for the Anteromedial Knee Rotatory Instability Treatment

Abstract

Injury to the medial compartment of the knee is the most common ligament injury to this joint. The medial approach must consider the presence of associated anteromedial instability. Untreated injury of these instabilities can result in failure of the other reconstructed ligaments. As treatment is usually associated with other ligaments, it is relevant that the technique could save grafts and synthetic material. This article aims to describe a technique for the treatment of anteromedial instabilities through semimembranosus tendon tenodesis in a more anterior and distal position, promoting the tensioning of the posteromedial structures.

Fig 1

Medial aspect of the access route to the posteromedial region of a left knee. Patient is in supine position. (A) Medial approach starts over the medial epicondyle up to 7 cm distal to the joint interline in the medial tibia surface. This approach is more posterior than the usual to facilitate deep dissection. (B) The longitudinal opening of the Sartorius muscle fascia and the medial retinaculum is performed. At this moment in the procedure, it is not frequently possible to visualize the ligament injury.

Fig 2

Medial aspect of the access route to the posteromedial region of a left knee. Patient is in supine position. (A) The semitendinosus (ST) and gracilis tendons are removed. N denotes the cutaneous branch of the saphenous nerve. (B) Identification of the direct tibial insertion of the semimembranosus tendon is individualized.

Fig 3

Medial aspect of the access route to the posteromedial region of a left knee. Patient is in supine position. After opening the superficial layers and removing the tendons from the semitendinosus and gracilis muscles, the posterior oblique ligament (POL) is identified, as well as the tendon of the semimembranosus muscle. N denotes the cutaneous branch of the saphenous nerve.

Fig 4

Medial aspect of the access route to the posteromedial region of a left knee. Patient is in a supine position. A K-wire is placed 10 mm anteriorly and 10 mm distally from the direct insertion of the SM tendon, and a temporary suture of this tendon is made, testing the flexion-extension of the knee to verify that there is no extension restriction. T denotes the direct tibial insertion of the semimembranosus tendon. N denotes the cutaneous branch of the saphenous nerve.

Fig 5

Preparation for tenodesis of the tendon of the semimembranosus muscle (SMT). Medial aspect of the posteromedial region of a left knee. Patient is in the supine position. (A) SMT is repaired with suture threads after being identified in its tibial portion in the posteromedial region of the tibia. A 10-mm distal and anterior spot (∗) is identified. (B) The two 5.0-mm metallic anchors are inserted. The most proximal tendon is shown immediately below the joint surface for the repair of the meniscotibial ligaments, and the second tendon is located at the point where the SMT tenodesis will be performed.

Fig 6

Position of the anchors. Medial aspect of the posteromedial region of a left knee. Patient is in the supine position. (A) The most anterior and distal anchor at the point where the SMT tenodesis will be performed. (B) The most proximal anchor immediately below the joint surface and posterior for the repair of the meniscotibial ligaments. Anchor used is made with TWINFIX / ULTRABRAID (Smith & Nephew, Andover, MA).

Fig 7

Position of the anchors. Medial aspect of the posteromedial region of a left knee. Patient is in the supine position. Final aspect of the semimembranosus tendon (SMT). Advancement and the medial meniscus (MM) repaired in the second anchor.

Fig 8

Reconstruction of the superficial medial collateral ligament. Medial aspect of the left knee. Patient is in supine position (A) Guide wires showing anatomical points for the construction of tunnels for ligament reconstruction. (B) Final aspect of ligament reconstruction with quadruple hamstring autograft.

Fig 9

Reconstruction of the superficial medial collateral ligament. Medial aspect of the left knee. Patient is in supine position, knee flexed at a 30º, neutral rotation without adduction. An 8×25 mm interference screw is placed to fix the new ligament.

Fig 10

Medial aspect of the left knee. Patient is in the supine position. (A) Final aspect of the graft placed, total extension is tested. (B) The remaining medial collateral ligament is repaired in the graft, and the subsequent layers are closed.