Review Question - QID 211427

This young patient has a varus knee with a history of ACL rupture and would likely benefit from a proximal tibial osteotomy with ACL reconstruction. However, a flexion contracture >15 degrees is a contraindication to performing the proximal tibial valgus osteotomy.

ACL deficiency alters knee kinematics and may contribute to accelerated degenerative changes within the medial compartment leading to subsequent injury to the meniscus or articular cartilage. A proximal tibial osteotomy may be used in this setting to treat both pain and instability by altering the posterior tibial slope changing the sagittal plane alignment, in addition to the coronal alignment. A proximal tibial osteotomy may be performed either simultaneously or in staged fashion with ACL reconstruction. It is not appropriate to perform ACL reconstruction prior to proximal tibial osteotomy in this setting, as varus alignment places increased stress on the reconstructed ACL. Indications for this procedure include young, active patient (<50 years) in whom an arthroplasty would fail due to excessive wear, healthy patient with good vascular status, non-obese patients, pain and disability interfering with daily life, only one knee compartment is affected, compliant patient that will be able to follow postoperative protocol. Contraindications to performing a proximal tibial osteotomy with ACL reconstruction include inflammatory arthritis, BMI>35, flexion contracture >15 degrees, knee flexion <90 degrees, >20 degrees of correction needed, varus-thrust on gait, and patellofemoral arthritis.

Rossi et al. reviewed high tibial osteotomy (HTO). They report that the clinical indications include varus alignment of the knee associated with medial compartment arthrosis, knee instability, medial compartment overload following meniscectomy, and osteochondral defects requiring resurfacing procedures. They conclude that HTO in combination with ACL reconstruction is commonly accepted to correct alignment and achieves durable results.

Noyes et al. reviewed 41 young patients with ACL deficiency, lower limb varus angulation, and varying amounts of posterolateral ligament deficiency. 73% of the patients had lost the medial meniscus and 63% had marked articular cartilage damage in the medial compartment. 34 patients were treated with HTO and ACL reconstruction. They report a reduction in pain and elimination of giving way in 71% and 85% of patients, respectively. They recommend HTO in addition to ligament reconstructive procedures in these knees with complex injury patterns.

Figure A is the full-length standing AP radiograph demonstrating varus malalignment of the left knee. Illustration A demonstrates the use of a proximal tibial osteotomy for cruciate deficient knees.

Incorrect Answers:
Answer 1: Proximal tibial osteotomy is indicated in young active patients
Answer 2: A BMI >35 is generally a contraindication to performing a proximal tibial osteotomy
Answer 3: A history of lateral meniscectomy may serve as a contraindication to performing a proximal tibial osteotomy
Answer 5: Varus alignment which would require greater than 20 degrees of correction would be a contraindication to performing a proximal tibial osteotomy