Abstract
Background:
Lower extremity alignment-correcting procedures for unicompartmental osteoarthritis are experiencing a rapid rise. Medial open-wedge high tibial osteotomy (MOW-HTO) thereby represents the most common technique among osteotomies but is limited in cases of severe malalignment. Some cases make a double-level osteotomy necessary.
Indications:
If planning of malalignment correction using a MOW-HTO results in a mechanical medial proximal tibial angle (mMPTA) of more than 93° (causing an oblique joint line), double-level osteotomy is indicated to avoid nonphysiological knee kinematics.
Technique Description:
After clinical examination and detailed analysis of malalignment (full-weight-bearing long-leg radiograph: hip-knee-angle [HKA], mMPTA, mechanical lateral distal femoral angle [mLDFA], joint line convergence angle [JLCA]), as well as individualized planning of the correction, the surgical procedure starts with an arthroscopy to evaluate the cartilage conditions and eventually treat intraarticular pathologies. Then, the femoral supracondylar correction is performed (closed wedge, biplanar osteotomy [to increase bony healing]) according to the presurgical planning by resecting the osteotomy wedge with the measured length. K-wires are placed to check the correction. An angle-stable plate is used for osteosynthesis. The wedge taken out will be used as bone stock for the MOW-HTO afterward. The biplanar open-wedge tibial osteotomy is then performed subsequently using a medial tibial approach and an angle-stable plate. Opening of the osteotomy is then performed and double checked with intraoperative fluoroscopy using an alignment rod. Postoperative partial weight bearing for 6 weeks is recommended.
Results:
In recent literature, only few publications report on results of double-level osteotomies. Babis et al reports that it is a valuable procedure for patients with large varus deformity. Nakayama et al noted a significant improvement in patient-registered clinical outcomes in early postoperative evaluation of 20 patients. Schröter et al reports on 37 knees and findings include good clinical results, despite progressive osteoarthritis.
Discussion/Conclusion:
In cases of severe malalignment, adequate axis correction may require a double-level osteotomy. Exact preoperative planning is essential. Results reported in recent publications are promising. By splitting 1 large correction into 2 smaller ones, complications like hinge fracture and delayed bone healing are lowered.
This is a visual representation of the abstract.
Video Transcript
Hi everyone, thanks for watching our video demonstrating the surgical technique of double-level osteotomy in severe varus malalignment of the knee joint by Jörg Harrer, Max Schenke, Christoph Lutter, Jörg Dickschas, Matthias Feucht, and Thomas Tischer from Germany.
There are no relevant disclosures.
In a nutshell, double-level osteotomy is a procedure for deformities not suitable for a single osteotomy.
Before surgery, detailed deformity analysis and correction planning is of uppermost importance. Surgery starts with arthroscopy to confirm the indication for joint preservation and to treat accompanying meniscus and cartilage lesions. Then, femoral lateral closed-wedge osteotomy and osteosynthesis are performed, followed by tibial medial open-wedge osteotomy. Next, leg alignment is checked radiographically and adjusted if necessary, followed by final tibial osteosynthesis. Only limited evidence exists regarding clinical long-term outcome so far; however, preliminary results are encouraging.
In conclusion, this is an advanced technique to correct large malalignment avoiding an oblique joint line.
The indication for the double-level osteotomy is symptomatic severe varus malalignment (usually ≥10°) and medial compartment osteoarthritis with a combined deformity in the femur and the tibia in active patients (mechanical lateral distal femoral angle [mLDFA] >90° and mechanical medial proximal tibial angle [mMPTA] <87°) and if preoperative planning of isolated open-wedge high tibial osteotomy (HTO) would result in mMPTA more than 93°.
Specific advantages of double-level osteotomy are that 1 osteotomy with high correction angle is divided into 2osteotomies with smaller angles, resulting in lower risk of hinge fractures and faster bone healing.
The presented case is a 55-year-old man with symptomatic beginning medial osteoarthritis with 10° of varus malalignment, as seen on full leg standing x-ray.
Detailed presurgical planning showed a mechanical lateral distal femoral angle of 89° and mechanical medial proximal tibial angle of 81°. A correction to almost 2° degrees of valgus was planned with 4° of femoral correction and 8° of tibial correction.
The surgery starts with diagnostic arthroscopy to ensure an intact lateral and patellofemoral compartment with treatment of potential associated meniscus and cartilage lesions. Here, arthroscopy showed grade IV cartilage lesions on the medial side.
Approach: No tourniquet is used. Anatomical structures are marked before the incision. A standard lateral subvastus approach is performed. Note the lateral genu recurvatum vessels on the lateral side, which are coagulated.
A special retractor is placed directly behind the cortex of the femur to protect especially the neurovascular structures. Two k-wires are placed in the planned position and angles to define the lateral wedge, which has to be removed for the closed-wedge osteotomy. The correct position of the 2 k-wires and of the retractor is controlled by fluoroscopy. Next, an angle-stable plate is temporarily placed and controlled under x-ray. A biplanar osteotomy is preferred because of better bone healing and increased stability. First, the oblique anterior part of the osteotomy is done with the oscillating saw and checked fluoroscopically. After that, the 2 main osteotomies are done along the guiding k-wires under fluoroscopy and the bone wedge is removed.
The final preparation of the osteotomy has to be done very exactly to prevent hinge fracture and is performed using chisels in this case.
In cases of a hinge fracture, an additional medial plate may be necessary, as shown in this x-ray, not related to the presented case.
When the medial hinge is mobile enough, the osteotomy can be closed manually with lateral compression and slight valgus movement.
The plate is then positioned and fixed distal with locking screws. The osteotomy is then closed manually and by the use of a bicortical nonlocking screw placed in the dynamic compression hole proximal to the osteotomy. You can nicely see the compression on the osteotomy. The complete closure of the osteotomy and the plate are checked by x-ray. All remaining locking screws are placed, and the nonlocking screw used for dynamic compression is replaced by a locking screw. Finally, a last check in both planes is performed.
After that, the medial open-wedge HTO is performed. After skin incision, the hamstring tendons are identified.
Then, a subperiostal release of the medial collateral ligament including the superior part of the pes anserinus is done.
A k-wire along the planned osteotomy and an additional hinge wire to protect the lateral hinge are placed under fluoroscopic control.
A retractor is placed behind the bony cortex to protect the soft tissues. Next, the main osteotomy is done along the guiding wire. In case of a patella infera or patellofemoral osteoarthritis, a descending osteotomy of the tibial tuberosity is preferred to avoid further distalization of the patella, as shown in this patient. After careful preparation, the hinge is mobile enough to open the osteotomy slowly with chisels under x-ray control.
Two parallel thick k-wires or Schanz screws are placed to control the sagittal plane during opening of the osteotomy. In this case, an additional extension osteotomy is done due to an extension deficit based on the high slope of the patient. To get a perfect bone contact on the ventral osteotomy, a small distal opening wedge is taken out in this osteotomy.
The osteotomy is opened with an arthrodesis spreader in full extension and the sloped reduced.
This can be controlled with the former parallel k-wires or Schanz screws. Fluoroscopic control is done. Time has to been taken now to control the axis of the leg with an alignment rod under fluoroscopic control of the Mikulicz line imaging the hip, the ankle, and the knee joint. Fine tuning of the final alignment can now be performed by increasing or decreasing opening of the tibial osteotomy.
An antero-posterior lag screw now gives compression on the descending osteotomy of the tibial tuberosity. You can nicely see the closure of the gap. Again, the osteotomy and the slope are controlled in lateral x-ray view.
The angle-stable plate is placed under fluoroscopic control and fixed with locking screws. The bone from the femoral osteotomy and the infratuberositary osteotomy is placed in the HTO as an autograft to optimize bone healing. Final x-ray and skin closure remark the final steps of the procedure. The planned correction was achieved on a full-leg x-ray on the sixth postoperative day.
Specific complications could be insufficient bony healing and correction loss, vascular lesions, over- or under correction, or infection. The rehabilitation does not differ from single-level osteotomies. We recommend limited weight bearing for up to 6 weeks, unlimited postoperative range of motion, continuous passive motion for 3 weeks, and a return to sport for high-impact sports not before 5 to 6 months.
Clinical studies showed that double-level osteotomy is a valuable procedure for patients with large varus deformity that cannot be corrected by single-level osteotomy as shown by Babis et al. Significant improvement in clinical outcome has been shown in early postoperative evaluation by Nakayama et al and Schröter et al, among others.
On this last slide, we present the recommended literature on the topic presented in this video.
We hope you enjoyed our video and if you have any questions or comments feel free to contact us!
Footnotes
One or more of the authors has declared the following potential conflict of interest or source of funding: T. T. is a paid consultant for Arthrex and Bauerfeind. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
