Double-Level Torsional Osteotomy in Severe Torsional Malalignment: A Surgical Technique

Abstract

Background:

Torsional malalignment of the femur and/or tibia is associated with patellar maltracking, and torsional osteotomies have shown to improve clinical symptoms. In patients with severe torsional malalignment, a double-level torsional osteotomy may be necessary.

Indications:

Symptomatic torsional malalignment leading to patellofemoral maltracking associated with anterior knee pain and/or patellofemoral instability.

Technique Description:

A double-level torsional osteotomy correcting both increased internal femoral torsion and increased external tibial torsion, is described. Meticulous preoperative deformity analysis and planning of the osteotomy is mandatory. An arthroscopy of the knee is performed first to evaluate the patellofemoral joint and patellar tracking. Tibial torsional correction is performed by a lateral approach. A biplanar osteotomy is performed, and the amount of torsional correction is controlled by 2 Schanz screws. Osteosynthesis can be done via a bended 5-hole DC-Plate or an angle-stable plate. The femoral osteotomy is performed by a medial approach. A uniplanar osteotomy is performed perpendicular to the mechanical axis of the femur. The amount of torsional correction is controlled by 2 Schanz screws. Osteosynthesis is achieved by an angle-stable plate.

Results:

Double-level torsional osteotomy has been shown to be an effective treatment for patients with patellar dislocation or subluxation associated with severe torsional malalignment. In a series of 18 patients, double-level osteotomy led to improved patellofemoral stability, decreased pain, and increases subjective outcome scores.

Discussion/Conclusion:

In patients with patellofemoral problems caused by a combined increased tibial external torsion and increased femoral internal torsion, a double-level torsional osteotomy is able to correct torsional angles to normal. Available clinical data on this procedure are promising.

Patient Consent Disclosure Statement:

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

Hello everyone. In this video, we want to present a technique of double-level osteotomy in severe torsional malalignment.

All authors have no relevant disclosures.

Background

We present here a double-level torsional osteotomy for torsional deformities in femoral and tibial aspect. The surgical technique starts with a presurgical evaluation and planning of the deformity correction. We start surgery with an arthroscopy to evaluate patella tracking but also to treat associated pathologies and to evaluate the trochlea. Afterward, we go on with a biplanar tibial torsional osteotomy and the osteosynthesis followed by a femoral torsional osteotomy and osteosynthesis. There is only limited evidence in long-term outcome about the procedure shown here, but first studies show a quite promising outcome.

Indications

The indication is a symptomatic torsional malalignment leading to patellofemoral maltracking. Symptoms appearing are anterior knee pain or/and patellofemoral instability. This is caused by a combined deformity of more than 10° torsional value on each femoral and tibial bone. The aim of the surgery is restoration of patellar tracking.

We present a case of a female, 25-year-old, patient who is suffering from recurrent patellar dislocations with a severe torsional deformity on both tibia and femur with also combined cartilage damage on the lateral trochlea.

In the clinical finding, we see an inwardly pointing knee on the right leg with an elevated femoral internal rotation and elevated tibial external rotation and a severe J-sign on the right side.

In the history of illness, the patient is suffering from patellar dislocations since adolescent age. In 2014, on both sides, a surgery was done with a trochleoplasty and a combined medial patellofemoral ligament (MPFL) augmentation.

Rotational analysis in computed tomography scans shows an elevated femoral anteversion of 12° and an elevated tibial external torsion of 11°.

Technique Description

Surgery starts with an arthroscopy. For better visualization, we use an extra proximal approach. Arthroscopic findings are a well-reconstructed trochlea with a severe patellar lateralization and combined cartilage damage.

Afterward, surgery goes on with a lateral approach to the tibial head combined with an incision for the Schanz screw. Preparation goes on with preparation of the patellar tendon. A small incision is made. The patellar tendon is afterward lifted up with a Hohmann retractor. Afterward, the first osteotomy performed is a tibial tubercle osteotomy with an oscillating saw. Water cooling is important. Now, the Schanz screws are placed for rotational control. First, the distal screw, afterward, the proximal screw is placed after direct visualization with a goniometer.

Preparation goes on with opening of the tibial anterior compartment and careful preparation of the soft tissue, especially in the dorsal aspect.

Afterward, the 5-hole DC-Plate is bended. Alternatively, you can use angle-stable blades here. Now the plate is inserted, radiographically controlled. Afterward, a Kirschner wire (K-wire) is placed to define the osteotomy level. A soft tissue retractor is placed in the dorsal aspect and also in the ventral aspect. Now the osteotomy is taking place with an oscillating saw. Be careful about the soft tissue and the tibial tubercle. Radiographic control of the soft tissue retractor is important. Afterward, the torsional correction is performed until both Schanz screws are parallel. You can see the internal rotation and ventralization of the tibial tuberosity. Afterward, the plate is inserted. The first screw hole is drilled under fluoroscopic control. The length is measured, and the screw is inserted. Now the distal screw is drilled and inserted, followed by the 2 screws which are crossing the osteotomy. These are important to increase stability and compression on the osteotomy. Finally, the last distal screw is drilled and inserted, and the osteotomy is fluoroscopically controlled. The parallel Schanz screws show a perfect torsional correction and the approach is closed layer by layer.

Next, femoral osteotomy starts by a medial approach. Incision of the vastus medialis fascia is done and the muscle is mobilized. The femoral bone is carefully prepared, especially the dorsal soft tissue. Afterward, an extra incision is performed for the proximal Schanz screw and bicortical predrilling is done. A 5-mm Schanz screw is inserted. It gives more stability than using a K-wire. Afterward, the distal Schanz screw is placed and the planned correction angel is visualized with a goniometer. Now the osteotomy level is controlled with fluoroscopy and a K-wire is inserted in 90° angle to the mechanical axis. Afterward, Hohmann retractors are placed in the ventral aspect and a soft tissue retractor is also placed in the dorsal aspect to protect vessels and nerve from injury. Now the osteotomy is performed uniplanar with an oscillating saw under water cooling and fluoroscopic control. Torsional correction is now performed by parallelization of both Schanz screws. Next, the plate is inserted and temporarily fixed with a K-wire. This is fluoroscopically controlled. And after control, the first angle-stable distal screw is predrilled and inserted using standard implants. Afterward, the compression screw is inserted bicortical in the first proximal hole bringing compression to the osteotomy. After fluoroscopic control, an additional incision is performed, and the remaining angle-stable screws are predrilled and inserted in the plate. The 2 proximal screws are inserted percutaneously in a minimally invasive approach. Afterward, the parallel Schanz screws show a perfect result. They are removed and the approach is closed layer by layer.

Results and Discussion

Radiograph control of the knee in 2 planes shows the perfect osteotomy in the femoral and tibial aspect. Note the dorsal bump in the femoral aspect due to the femoral correction.

Arthroscopic control during hardware removal after 12 months shows perfect patellar tracking without lateralization.

Specific but rare complications of this osteotomy could be insufficient bone healing or correction loss, vascular or nerval lesions, redislocations of the patella, or compartment syndrome in the tibial aspect.

The rehabilitation is quite similar to other axis correction osteotomies with limited weightbearing for up to 6 weeks. There is an unlimited postoperative range of motion, and continuous passive motion is recommended for about 3 weeks. Return to sports and high-impact sports are not possible before 5 to 6 months after surgery.

The outcome is very promising in the existing literature showing significant pain relief, significant improvement in clinical scores, and a normalization of patellar tracking. An additional MPFL plasty can be performed if necessary at the time of hardware removal, which is also an advantage of the medial approach.^1-5

This slide shows some further references leading more to the topic. Notice specially number 6 which shows the measurement technique after Waidelich and number 7 which shows the normative values according to Strecker.^1-5

Thank you for watching this video about the surgical technique of torsional double-level osteotomies.