Complications of a self-centering sliding tibial tubercle osteotomy for patellofemoral complaints; low incidence of non-union and fracture

Revision lateralization osteotomy of the tibial tubercle has excellent outcomes in patients suffering from previous medial tibial tubercle overcorrection

INTRODUCTION

Tibial tubercle osteotomy (TTO) is a common procedure used to treat patients with patellofemoral instability (PFI) and osteoarthritis (PFOA). Medial patellar maltracking due to previous excessive medialization of the tibial tubercle has rarely been reported. Therefore, the goal of this study was to assess patient-reported outcome measures (PROMs) after revision osteotomy with lateralization of the tibial tubercle (RL-TTO) to correct medial patellofemoral maltracking.

MATERIALS AND METHODS

Between 2017 and 2021, a series of 11 patients (male/female 1/10; age 35.8 ± 10.5 years) were treated by RL-TTO, of whom 8 patients could be retrospectively evaluated after a mean of 32.4 ± 15.1 months (range 18-61 months) postoperatively. The Kujala anterior knee pain scale, the patellofemoral subscale of the Knee Osteoarthritis and Outcome Score (KOOS-PF), and a numeric analog scale (NAS; 0-10) regarding anterior knee pain (AKP) at rest and during activity were assessed from pre- to postoperatively.

RESULTS

The preoperative mean tibial tubercle-trochlear groove (TT-TG) and tibial tubercle-posterior cruciate ligament (TT-PCL) distances were - 6.5 ± 6.5 mm and 0.7 ± 4.6 mm, respectively. The intraoperatively determined amount of tibial tubercle lateralization averaged 10.7 ± 3.6 mm. The Kujala score and KOOS-PF improved significantly from 33.6 ± 10.1 (23-51) points to 94.4 ± 6.2 points (82-100) (p < 0.001) and from 20.6 ± 13.2 points (0-43.3) to 87.3 ± 9.9 points (72.8-100) (p < 0.001) from pre- to postoperatively, respectively. Pain at rest decreased from 5.8 ± 1.9 to 0.8 ± 0.9 (p < 0.001), and pain during activity decreased from 8.6 ± 1.3 to 1.6 ± 1.5 (p < 0.001).

CONCLUSION

RL-TTO significantly improved subjective knee function and AKP in patients suffering from medial patellar maltracking due to previous excessive tibial tubercle medialization osteotomy at short-term follow-up.

Prevalence of trochlear dysplasia in symptomatic isolated lateral patellofemoral osteoarthritis: Transverse study of 101 cases

INTRODUCTION

Patellofemoral osteoarthritis (PFOA) is usually associated with femorotibial osteoarthritis; isolated forms involve several specific risk factors. Trochlear dysplasia (TD) alters stress patterns in the patellofemoral joint, inducing PFOA. The association of TD and isolated PFOA was analyzed without distinguishing medial facet, global and lateral facet involvement. The study hypothesis was that TD prevalence is high in isolated lateral PFOA (ILPFOA). The aim of the study was to assess TD prevalence in a symptomatic ILPFOA population and identify risk factors.

PATIENTS AND METHODS

Eighty-four patients (101 knees) underwent lateral vertical patellectomy (LVP) for symptomatic ILPFOA between November 1998 and September 2019. Demographic, clinical and radiographic data were collected retrospectively from preoperative records. TD was analyzed by 2 blinded surgeons on lateral radiographs.

RESULTS

TD prevalence was 88.1%. TD was significantly more advanced in patients under 45 years of age at surgery (64.5% stage 2 or 3; p=0.019). Non-TD cases showed significantly more frequent valgus deformity (83.3%; p=0.042) and overweight (BMI, 32±4.1; p<0.001).

CONCLUSION

TD is a known risk factor for PFOA, present in almost 9 in 10 cases in the present series of ILPFOA. These findings reinforce the hypothesis that it plays a role in onset of ILPFOA. TD also induces early pain, leading to surgery. Overweight and valgus deformity are contributing factors for ILPFOA.

LEVEL OF EVIDENCE

IV; transverse study.

Percutaneous Reconstruction of the Medial Patello-Femoral Ligament Using Dynamic Gracilis Tendon Transfer

BACKGROUND

Many techniques have been described for reconstructing the medial patello-femoral ligament (MPFL), using a variety of transplants and fixation methods to treat patello-femoral dislocation. The main challenge with static transfers is to position the femoral fixation point at the site that best restores MPFL anisometry. The objective of this cadaveric study was to propose a version of the initially described dynamic gracilis transfer technique that can be performed percutaneously.

HYPOTHESIS

Our working hypothesis was that using a minimally invasive approach would provide better cosmesis without altering the biomechanical efficacy of the procedure.

METHODS

20 cadaveric knees were used to evaluate the feasibility and reliability of our percutaneous technique. We analysed femoral pulley location and scar length.

RESULTS

After dissection, the position of the femoral pulley allowed superimposition of the transplant along the trajectory of the native MPFL in all 20 knees. Cumulative scar length was 6.5cm (range, 6-7.5cm).

DISCUSSION

Percutaneous dynamic gracilis transfer is easy to perform, reproducible, and capable of creating a pulley that anatomically replicates the femoral insertion point of the native MPFL.

LEVEL OF EVIDENCE

IV; retrospective study.