Anterolateral approach using tibial tubercle osteotomy for total knee arthroplasty: can we predict failure?

The type of approach does not influence TKA component position in revision total knee arthroplasty - A clinical study using 3D-CT

BACKGROUND

The influence of the surgical approach on the position of the prosthetic components in revision of total knee arthroplasties (rTKA) is still not clear. This study compared the medial parapatellar approach (MPA) and lateral parapatellar subvastus approach with tibial tubercle osteotomy (LPA).

METHODS

Forty-two consecutive patients underwent rTKA from 2006 to 2016 with either MPA (n=21) or LPA (n=21) because of aseptic loosening, infection, malposition or instability (mean follow-up: 41.5months). Revision TKA component position and leg alignment were assessed on three-dimensional CT (3D-CT) images and compared between groups using a t-test (p<0.05). Rotation of rTKA components graded into internal, neutral or external rotation and rates of postoperative complications and revisions were compared between groups with a chi²-test (p<0.05).

RESULTS

Group MPA and LPA showed no significant differences with respect to the femoral component (coronal: 0.6° vs 0.9°; sagittal: 7.5° vs 7.7°; transversal: 0.4° vs -0.2°), tibial component (coronal: 0.1° vs 0.3°; sagittal: 3.1° vs 1.6°; transversal: 6.9° vs 9.3°) and leg alignment (varus: 0.2° vs 1.1°) (p<0.05). Group LPA showed a non-significant (p=0.25) higher incidence of neutrally (28.6% vs 9.5%) and less internally (23.8% vs 38.1%) rotated tibial components. Rates of complication and revisions did not differ significantly.

CONCLUSIONS

In contrast with primary TKA, the two approaches did not influence postoperative rTKA position. This can be explained with the more extensive approach at rTKA and means that no corrections of the orientation of the components are needed performing either MPA or LPA.

Tibial tubercle osteotomy (TTO) in total knee arthroplasty, is it worth it? A review of the literature

INTRODUCTION

Tibial tubercle osteotomy (TTO) is a well-established extensile approach to improve joint visualization and implant removal. Despite this, TTO is a challenging technique with a long learning curve and potential pitfalls. Complications are not infrequent, even if performing the correct surgical steps. Aim of this paper is to review the current literature about TTO, its safeness and reliability, and finally the complications rate.

MATERIALS AND METHODS

We performed a systematic review of the available English literature, considering the outcomes and the complications of TTO. The combinations of keyword were "tibial tubercle osteotomy", "total knee arthroplasty", "total knee revision", "outcomes", "complication" and "surgical approach".

RESULTS

From the starting 322 papers available, 26 manuscripts were finally included. Most of the papers show significant improvements in clinical outcomes, both in primary and in revision procedures. Radiographic fragment healing is close to 100%. Related complications can range from 3.8-20%.

CONCLUSION

TTO may be necessary to correct pathological tuberosity position or patella tracking. However, TTO is a challenging technique to improve the surgical approach during total knee arthroplasty. A strict surgical technique can lead to better results and to minimize complications. However, it is not clear if the improved outcome can outweigh the longer surgery and the higher risk of pitfalls.

Tibial tubercle osteotomy to improve exposure in complex knee fractures: A cadaveric study and case series

Adequate exposure is fundamental to safely and correctly perform open procedures around the knee. Tibial tubercle osteotomy (TTO) has previously been described as a method to improve exposure, particularly in complex primary elective knee arthroplasty or revision surgery. We describe a tibial tubercle osteotomy technique to improve exposure in complex knee fractures and a cadaveric study and trauma case series.

METHODS

A cadaveric study using 8 knee specimens was conducted using a lateral subvastus approach to the knee. Standardised pictures were taken of the exposure, the tibial tubercle osteotomy was performed and pictures were taken of the new exposed area. These images were compared using a computer program that calculated the area of exposure before and after tibial tubercle osteotomy and the results analysed. The technique was then used in a case series of 6 different complex knee fractures including three distal femoral, one periprosthetic distal femur and two tibial plateau fractures. The outcomes of these patients were followed clinically and radiologically.

RESULTS

All specimens in the cadaveric study demonstrated an increase in area of exposure after the TTO with a mean increase of 148%. All tibial tubercle osteotomies performed in the trauma case series were united by 6 months without complication.

CONCLUSIONS

Tibial tubercle osteotomy is a recognised technique for improving exposure to the knee. This has been demonstrated in a cadaveric study and in a case series of six complex fractures around the knee. If performed properly, this technique can be extended to appropriate trauma cases with good results.

Equivalent results of medial and lateral parapatellar approach for total knee arthroplasty in mild valgus deformities

PURPOSE

When performing total knee arthroplasty (TKA) in valgus knee deformities, a medial or lateral parapatellar approach can be performed, but the lateral approach is often considered technically more difficult. The purpose of this study was to compare intra-operative, early clinical and radiological outcomes of medial and lateral parapatellar approaches for TKA in the setting of moderate knee valgus (<10°).

METHODS

We prospectively analysed 424 knees with pre-operative valgus deformity between 3° and 10° that underwent TKA over an 18-year period; 109 were treated with a medial approach and 315 with a lateral approach. Intra- and post-operative outcomes and complication rates after a minimum follow-up of one year were compared.

RESULTS

Tourniquet (p = 0.25) and surgical (p = 0.62) time were similar between groups. The popliteus tendon was released more frequently in the medial-approach group (p = 0.04), while the iliotibial band was released more frequently in the lateral-approach group (p < 0.001). A tibial tuberosity osteotomy was performed more frequently in the lateral- than medial-approach group (p = 0.003). No significant differences in limb alignment (p = 0.78), or Knee Society Score (KSS) knee (p = 0.32) and function (p = 0.47) results were noted based on surgical approach, and complication rates were similar between groups (p = 0.53).

CONCLUSIONS

Lateral parapatellar approach is a safe and effective surgical technique for performing TKA in moderately valgus knees. These equivalent early results are encouraging for systematic use of the lateral approach in moderately valgus knees.

Tibial tubercle osteotomy in septic revision total knee arthroplasty

PURPOSE

The incidence of revision knee arthroplasty for infection is increasing and the required surgical approach for the revision is a challenge for surgeons. Extensile approaches are frequently used when it is impossible to evert the extensor mechanism. The aim of this paper is to report our experience with tibial tubercle osteotomy (TTO) and the functional results in patients who underwent a two-stage revision due to prosthesis infection.

METHODS

Twenty-six patients underwent a TTO as a surgical approach in the second stage of revision for infection. The patients were clinically assessed by means of functional scales (the Knee Society Score and WOMAC) and X-rays.

RESULTS

The TTO healed without complications in 22 patients (84.6%) and the average length of follow-up was 3.4 years. Non-union was observed in two patients. One patient presented an extension lag of 5°. A total of 23 patients (88.4%) were free from infection. Twenty-five patients (96.1%) had better scores on the Knee Society Score and WOMAC after the procedure.

CONCLUSIONS

In patients undergoing the second stage of revision total knee arthroplasty for infection, the TTO approach provides a large operating field. This enables surgeons to withdraw spacers and position new implants without damaging the extensor mechanism of the knee or altering the postoperative rehabilitation process. The complications that have been reported as a result of this procedure could be reduced by performing a meticulous surgical technique.

LEVEL OF EVIDENCE

Retrospective case series, Level IV.