High tibial derotation osteotomy for distal extensor mechanism alignment in patients with squinting patella due to increased external tibial torsion

Double Level Knee Derotational Osteotomy Yields Better Postoperative Outcomes than Tibial Tubercle Transfer Combined with Medial Patellofemoral Ligament Reconstruction in Patients with Recurrent Patellar Instability and Severe Malrotation

PURPOSE

To assess the postoperative outcomes of double level knee derotational osteotomy (KDRO) combined with medial patellofemoral ligament reconstruction (MPFLR), and to compare it with tibial tuber transfer (TTT) and MPFLR without derotational osteotomy in patients with recurrent patellar instability (RPI) and a marked torsional deformity.

METHODS

From March 2020 to December 2021, patients with torsion deformity (combined femoral torsion and tibial torsion ≥ 30°) were retrospectively included. The minimum follow-up time was 18 months. Patients received KDRO and MPFLR were categorized into KDRO group and patients received a combined TTT and MPFLR were categorized into control group. Preoperative and postoperative clinical symptoms, patient-reported outcomes (PROs) (Kujala, visual analogue scale [VAS], Lysholm, International Knee Documentation Committee [IKDC], Tegner, and Knee Injury and Osteoarthritis Outcome [KOOS] scores) and imaging parameters (femoral torsion, tibial torsion, patellar height, femoral trochlear dysplasia, congruence angle, patellar tilt angle, lateral patellar angle, lateral patellar translation, and tibial tubercle-trochlear groove distance) were analyzed.

RESULTS

In all, 36 patients were included with 18 in KDRO group and 18 in control group. The mean follow-up time was 30 (range 21-39) months. At the latest follow-up, no patient experienced re-dislocation in either group. Except for the femoral torsion and tibial torsion in the control group, postoperative imaging parameters were significantly reduced to the normal range. KDRO group has a lower patellar tilt angle (P=.043, effect size 0.64). All clinical scores in both groups significantly improved postoperatively. KDRO group has better functional scores than control group except the KOOS daily living activities subscore and the KOOS sports and recreation subscore. More proportions of patients in KDRO group met the minimal clinically important difference (MCID) for most PROs than control group. Eight patients (44%) in the control group complained of postoperative anterior knee pain, compared with 1 patient (6%) in KDRO group (P=.018).

CONCLUSION

KDRO combined with MPFLR was associated with better postoperative outcomes than TTT combined with MPFLR in patients with RPI and a torsion deformity.

Tibial derotational osteotomy for idiopathic tibial torsion: A systematic review of surgical indications based on clinical presentation and measurement technique

PURPOSE

The aim of this systematic review was to identify the surgical indications of tibial derotational osteotomy (TDO) in patients with idiopathic external tibial torsion (ETT) and identify common measurement thresholds for surgical correction.

METHODS

A systematic search of MEDLINE and Embase via Ovid, Cochrane Library via Wiley, Web of Science, Scopus, SPORTDiscus via EBSCOhost, ClinicalTrials.gov, WHO ICTRP and Global Index Medicus databases was performed with search terms reflecting the concepts of idiopathic tibial torsion, TDOs, and surgical indications. Studies reporting surgical indications and measurement methods of idiopathic tibial torsion in patients who underwent TDO were included. Two authors independently screened articles and extracted data that was characterized with descriptive statistics.

RESULTS

Seventeen studies were identified for inclusion, with 460 tibias and 351 patients. Nearly all patients who underwent surgery had either anterior knee pain or patellar instability, even if other indications were present. Of all included patients, the most common surgical indications for TDO were anterior knee pain (88%), patellar instability (59%), gait dysfunction (41%) and cosmetic deformity (12%). Twelve studies (71%) cited multiple of these indications as reasons for surgery. On physical exam, tibial torsion was measured most commonly by thigh-foot angle (59%) (TFA) and transmalleolar axis (24%) (TMA). In terms of TFA, the most frequently reported cut-off for ETT was >30° (35%). Computerized tomography (CT) was used by nine studies (53%). The most common CT axes used to measure ETT were the TMA with respect to the posterior tibia condylar axis or the bicondylar tibia axis.

CONCLUSION

Anterior knee pain and/or patellar instability are common indications for TDO in patients with idiopathic tibial torsion. Standardized TFA thresholds (>30°) and CT measurement methods (TMA and posterior tibia condylar or bicondylar tibial axis) may help further establish objective surgical indications.

LEVEL OF EVIDENCE

IV.

Derotational high tibial osteotomy in cases of anterior knee pain and/or patellofemoral instability: a systematic review

IMPORTANCE

Derotational high tibial osteotomy (HTO) is a surgical intervention for correcting rotational malalignments in the lower limb, which may contribute to anterior knee pain (AKP) and/or patellofemoral instability (PFI). This surgical technique is not yet widely implemented and requires a systematic evaluation of its outcomes.

AIM

To assess the effectiveness of derotational HTO in correcting rotational malalignments of the lower limb in patients with AKP and/or PFI through radiological, clinical, and patient-reported outcome measures.

EVIDENCE REVIEW

Searches were conducted in the PubMed, Embase, and Web of Science databases up to March 3, 2023, to identify studies utilizing derotational HTO in patients with AKP and/or PFI. The primary outcome measures of interest were measurements of lower limb angular correction. Other radiological, clinical, and patient-reported outcome measures were also analyzed. The risk of bias was judged with the RoBANS tool.

FINDINGS

A total of 8 studies were included, comprising 215 patients (27.0 ​± ​3.9 years) and 245 knees. The most reported angle was tibial torsion (k ​= ​6 studies, n ​= ​173 knees), with a mean difference between postoperative and preoperative values (postsurgical correction) ranging from -37.8° to -10.8°. Patient-reported outcome measures showed significant improvements in the postoperative moment, exceeding the minimal clinically important difference in almost all cases, and with high patient satisfaction (93.6%).

CONCLUSIONS AND RELEVANCE

Derotational HTO allows the correction of rotational malalignments of the lower limb (tibial torsion) and promotes patient satisfaction.

LEVEL OF EVIDENCE

Level IV.

Derotational Hybrid Closed-Wedge High Tibial Osteotomy for Knee Osteoarthritis With Patellar Subluxation Caused by Tibial Torsional Deformity

Patellar subluxation and recurrent dislocation are commonly treated with medial patellofemoral ligament reconstruction, and patients with predisposing factors for these problems often require additional bony realignment procedures. However, these procedures mainly address problems in the axial plane, and patients with medial-compartmental knee osteoarthritis may require further realignment in the coronal plane. In this Technical Note article, we introduce our technique for derotational hybrid closed-wedge high tibial osteotomy. Using this technique, simultaneous 3-dimensional realignment in the axial, coronal, and sagittal planes can be achieved in patients with medial compartmental knee osteoarthritis and patellar subluxation caused by a tibial torsional deformity. The indications for the technique and the preoperative planning assessments involving a static torsional deformity analysis on computed tomography images and a dynamic gait analysis by our walking-on-paper method are presented. This is followed by a detailed description of the surgical procedure, together with consideration of the pearls and pitfalls of the procedure. A video of the surgery performed in a representative case with medial knee osteoarthritis and patellar subluxation in the right knee owing to an outward tibial torsion deformity is also provided.

Tibial Tuberosity Rotation in Patients With Patellar Instability Versus Age- and Sex-Matched Controls

Background

Several methods have been described to measure external rotation of the tibial tuberosity; all use femoral landmarks.

Purpose

To develop reproducible tibial-based methods to measure external rotation of the tibial tuberosity in patients with patellar instability.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were magnetic resonance images of 61 patients with patellar instability and 61 age- and sex-matched healthy controls. Three novel methods using tibial landmarks to measure the rotation of the tibial tuberosity (plateau axis-tuberosity axis [PA-TA] angle, tibial geometric center-tuberosity axis [GC-TA] angle, and plateau axis-midtuberosity point [PA-MT] angle) as well as a femoral-based rotational measurement (surgical transepicondylar axis-tuberosity axis [sTEA-TA] angle) and the tibial tuberosity-trochlear groove (TT-TG) distance were measured and compared in instability patients and controls using unpaired t tests, and the cutoff values for predicting instability were calculated using receiver operating characteristic curves. The correlations between the angle measurements and the TT-TG distance were analyzed.

Results

Instability patients had significantly higher external rotation of the tibial tuberosity compared with controls with regard to the PA-TA angle (18.2° ± 9.6° versus 13.1° ± 6.8°; P = .001), GC-TA angle (8.4° ± 4.5° versus 11.5° ± 3.9°; P = .0001) and sTEA-TA angle (122° ± 8.5° versus 113.6° ± 6.3°; P = .0001). The mean TT-TG distance was also significantly higher in the instability group (18.2 ± 5.4 versus 11.5 ± 2.7 mm; P = .001). The cutoff values were 17.5° (area under the receiver operating characteristic curve [AUC] = 0.66) for PA-TA angle, 8.5° (AUC = 0.705) for GC-TA angle, 118.8° (AUC = 0.79) for sTEA-TA angle, and 15.2 mm for TT-TG distance (AUC = 0.863). PA-TA angle was significantly correlated with all other measurements (r = 0.35-0.71; P ≤ .006 for all), whereas sTEA-TA angle had the strongest correlation with TT-TG distance (r = 0.78; P = .001).

Conclusion

The tibial tuberosity was externally rotated in patellar instability patients compared with age- and sex-matched controls, and this intrinsic malalignment of the proximal tibia was demonstrated in the tibial-based measurements.

Effect of Lower Extremity Torsion on Clinical Outcomes After Medial Patellofemoral Ligament Reconstruction and Tibial Tubercle Transfer for Recurrent Patellofemoral Instability

BACKGROUND

Increased femoral torsion (FT) or tibial torsion (TT) has been suggested to be a potential risk factor for recurrent patellofemoral instability. However, the influence of increased FT or TT on the postoperative clinical outcomes of recurrent patellofemoral instability has rarely been investigated.

PURPOSE

To assess the effect of increased FT or TT on postoperative results in patients with recurrent patellofemoral instability after combined medial patellofemoral ligament reconstruction (MPFLR) and tibial tubercle transfer, along with the influence of other risk factors.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Out of 91 patients, the study's analyses included 86 patients with recurrent patellofemoral instability who were treated with MPFLR and tibial tubercle transfer and enrolled between April 2020 and January 2021. FT and TT were assessed using preoperative computed tomography images. According to the torsion value of FT or TT, patients were categorized into 3 groups for each of FT and TT: group A (<20°), group B (20°-30°), and group C (>30°). Patellar height, femoral trochlear dysplasia, and the tibial tuberosity-trochlear groove (TT-TG) distance were also assessed. Patient-reported outcome scores (Tegner, Kujala, International Knee Documentation Committee [IKDC], Lysholm, and Knee injury and Osteoarthritis Outcome Score [KOOS]) were evaluated pre- and postoperatively. Clinical failure of MPFLR was recorded. Subgroup analysis was conducted to evaluate the effect of increased FT or TT on the postoperative outcomes.

RESULTS

A total of 86 patients were enrolled with a median follow-up time of 25 months. At the final follow-up, all functional scores improved significantly. Patella alta, high-grade trochlear dysplasia, and increased TT-TG distance did not have any significant effect on the postoperative functional scores. Regarding FT, subgroup analysis indicated that all functional scores of group C were lower than those of groups A and B except the KOOS knee-related Quality of Life score. For TT, group C had lower scores than group A for all functional outcomes except Tegner and KOOS Quality of Life and lower scores than group B for Kujala, IKDC, KOOS (Symptoms and Sport and Recreation subscales), Tegner, and Lysholm scores. The comparison between group A and group B, whether for FT or TT, revealed no significant differences.

CONCLUSION

For patients with recurrent patellofemoral instability, increased lower extremity torsion (FT or TT >30°) was associated with inferior postoperative clinical outcomes after combined MPFLR and tibial tubercle transfer.

Tibial Derotational Osteotomy for Patellofemoral Instability: A Systematic Review

Introduction

The etiology of patellofemoral (PF) instability is multifactorial. Excessive external tibial torsion has been associated with recurrent patellar subluxation and persistent anterior knee pain. Several surgical techniques have been historically used to correct this, including medial patellofemoral ligament reconstruction, tibial tuberosity transfer (TTT), trochleoplasty, and tibial derotation osteotomy (TDO). The purpose of this systematic review is to investigate the safety and efficacy of TDO for PF instability and pain.

Methods

A thorough search of the literature was conducted on July 15, 2022. Seven studies met the inclusion criteria for this systematic review.

Results

Among the included studies, there were 179 total subjects and 204 operative knees. Mean follow-up time was 66.31 months (range 11-192). Complication rate was low (12.8%) in studies that reported complications. Average degree of anatomical correction in the transverse plane was 19.9 degrees with TDO. This increased to 34 degrees when combined with TTT. All PROMs assessed were significantly increased postoperatively (p < 0.05). Age greater than 25 years and advanced PF chondromalacia may negatively affect postoperative outcomes.

Conclusion

The primary findings of this review were as follows: (1) TDO results in significantly improved pain and PROM ratings in patients with PF pain and/or instability, (2) the likelihood of complication, including recurrent patella subluxation after TDO, is low but may be increased by aging, and (3) the successful anatomical correction of TDO may be augmented by concurrent TTT in some cases.

Correlation of Tibial Torsion With Lower Limb Alignment and Femoral Anteversion in Patients With Patellar Instability

BACKGROUND

Alignment and rotation of the lower extremities have been suggested to be predisposing pathologic factors for patellar instability.

PURPOSE

To elucidate the relationship between the lower limb alignment and lower extremity rotation in patients with patellar instability.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Included were 83 patients with patellar instability. Computed tomography scans and standing full-leg radiographs were used to measure the tibial tuberosity-trochlear groove (TT-TG) distance, mechanical femorotibial angle (mFTA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), femoral torsion, and tibial torsion of the different segments. The relationships between femoral torsion, tibial torsion of the different segments, and the mFTA, mLDFA, and mMPTA were evaluated. The levels of tibial torsion and femoral torsion in patients with varus, normal, or valgus alignment were compared with 1-way analysis of variance and chi-square test.

RESULTS

The total tibial torsion was significantly associated with total femoral anteversion (r = 0.329; P = .002) and mFTA (r = -0.304; P = .005). There were no significant correlations between mFTA and TT-TG distance or femoral anteversion. Compared with patients with valgus malalignment, patients with varus malalignment tended to have higher tibial torsion.

CONCLUSION

Tibial torsion was associated with leg axis alignment and femoral anteversion in patients with patellar instability. Patients with patellar instability, especially those with concurrent leg axis deformities, should undergo further radiological imaging so that tibial torsion can be assessed and a diagnosis of torsion deformity made early in the treatment pathway and the proper surgical plan formulated.

The incidence of complications after derotational femoral and/or tibial osteotomies in patellofemoral disorders in adolescents and active young patients: a systematic review with meta-analysis

PURPOSE

To quantify the risk of perioperative and postoperative complications of derotational femoral and/or tibial osteotomies in patellofemoral disorders (anterior knee pain and patellar instability) in adolescents and active young patients.

METHODS

MEDLINE, EMBASE, Cochrane and Scopus databases were used to identify studies published from database inception and June 30, 2021. Meta-analysis was performed to pool the rates of complications related to femur and tibia osteotomies. Values of proportion of complications were expressed as proportions and 95% confidence intervals (CI) and then transformed using a Freeman Tukey double arcsine transformation. Meta-regression was used to explore factors that potentially may influence on heterogeneity such as year of publication, quality of the included studies and site of the osteotomy.

RESULTS

The 22 studies identified included a total of 648 derotational osteotomies in 494 patients. Studies consisted of 20 case series (non-comparative) and 2 comparative observational non-randomized cohorts. Tibial osteotomies showed higher risk of complications than femoral osteotomies (random pooled prevalence 9%; 95% CI 4-15% versus 1%; 95% CI 0-5%, respectively, p < 0.01). The meta-regression analysis of the articles showed that the only parameters responsible of the variance in number of complications were the osteotomy site.

CONCLUSIONS

Derotational femoral and/or tibial osteotomy is a safe surgical procedure in the treatment of patellofemoral disorders (anterior knee pain and patellar instability) in adolescents and active young people.

LEVEL OF EVIDENCE

IV.