Outcomes After Derotational Distal Femoral Osteotomy for Recurrent Patellar Dislocations With Increased Femoral Anteversion: A Systematic Review and Meta-analysis

PurposePatellofemoral instability (PFI) is a common condition that can be caused from multiple factors, including lower limb rotational malalignments. Determining precise criteria for performing corrective torsional osteotomy can be a daunting task due to the lack of consensus on normal and excessive values and the limited evidence‐based data in the postoperative results. The purpose was to assess the clinical, functional and imaging outcomes following derotational distal femoral osteotomy (DDFO) in patients with PFI and/or anterior knee pain (AKP) associated with lower limb rotational malalignments.MethodsSearches were conducted on PubMed, EMBASE and Web of Science databases up to October 2023. Studies reporting outcomes after DDFO in patients with PFI and/or AKP were eligible for the systematic review. The primary outcome was imaging metrics, especially femoral anteversion. Secondary outcomes included the patient‐reported outcome measures (PROMs) (clinical and functional). Quantitative synthesis involved the use of weighted averages to calculate pre‐ to postoperative mean differences (MD) and compare them against the minimal clinically important difference (MCID).ResultsTen studies (309 knees) were included with a mean follow‐up of 36.1 ± 11.7 months. Imaging outcomes consistently indicated the correction of femoral anteversion (MD = −19.4 degrees, 95% confidence interval: −20.1 to −18.7) following DDFO. PROMs showed significant improvements in most studies, exceeding the MCID. Patient satisfaction with the DDFO was high (93.3%).ConclusionsThe DDFO was an effective treatment option for correcting excessive femoral anteversion in patients with PFI associated with clinically relevant functional and clinical improvement and a high satisfaction rate.Level of EvidenceLevel IV, systematic review of level II–IV studies

Section: Discussionmentioning

confidence: 99%

Section: Risk Of Biasmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Derotational distal femoral osteotomy corrects excessive femoral anteversion in patients with patellofemoral instability: A systematic review

Ribeiro,

Gomes,

Ferreira

et al. 2024

“…Three lines were drawn to evaluate femoral torsion in CT images. (1) The section showing the entire femoral head and neck of the femoral head was selected. The first line passes through the centre of the femoral head and neck (FN, Figure 1a).…”

Section: Evaluation Of Femoral Torsionmentioning

confidence: 99%

“…The femoral rotational malformation is an important part of abnormal bone structure, and in recent years, its influence on patellar instability has attracted increasing attention [1][2][3]. Femoral anteversion (FA), used to evaluate overall femoral torsion, is usually measured by the angle between the line passing through the centre of the femoral head and neck and the tangent line to the posterior condyles.…”

Section: Introductionmentioning

confidence: 99%

Clinical outcomes of derotational femoral osteotomy combined with medial patellofemoral ligament reconstruction in patients with patellar dislocation and increased femoral anteversion unaffected by the pattern of distribution of femoral torsion

Fan,

Niu,

Hao

et al. 2024

Self Cite

PurposeThe aim of this study was to evaluate the clinical effect of derotational femoral osteotomy combined with medial patellofemoral ligament reconstruction for patellar dislocation and the effect of the distribution of femoral torsion at different segments on postoperative function.MethodsForty‐two patients with patellar dislocation who underwent derotational femoral osteotomy from 2017 to 2021 were retrospectively analysed. All patients received computed tomography scans from the hip to the knee to evaluate correction of the femoral anteversion (FA) angle, patellar tilt angle (PTA) and congruence angle (CA) after derotational femoral osteotomy. Subjective scores, such as the Kujala, Lysholm, International Knee Documentation Committee (IKDC), Tegner and visual analog scale (VAS) scores, were used to evaluate knee function before and after the operation. Patients with supracondylar torsion > distal torsion were categorized into the supracondylar torsion group and patients with distal torsion > supracondylar torsion were categorized into the distal torsion group. Subgroup analyses were performed.ResultsNo presentation of redislocation occurred in these patients at the minimum 2‐year follow‐up visit. The mean preoperative FA angle in the supracondylar torsion group was 30.2° ± 4.2°, and the mean postoperative FA angle was 14.5° ± 2.5° (p < 0.001). The mean preoperative FA angle was 26.7° ± 1.4° and the mean postoperative FA angle was 14.1° ± 1.4° in the distal torsion group. In addition, postoperative PTA and CA were significantly corrected in both groups (p < 0.001). The postoperative Kujala, Lysholm, IKDC, Tegner and VAS scores were significantly improved in both groups (p < 0.001). Subgroup analyses showed a higher preoperative FA in the supracondylar torsion group and a higher occurrence of high‐grade trochlear dysplasia in the distal torsion group. However, there was no significant difference in their postoperative clinical outcomes.ConclusionThrough a minimum of 2‐year follow‐up visits of patients with patellar dislocation and increased FA, it was found that derotational femoral osteotomy could significantly reduce FA and improve subjective knee function. The pattern of torsion distribution did not significantly affect the clinical outcomes of derotational femoral osteotomy. These findings readvised orthopaedic surgeons that derotational femoral osteotomy remains the preferred procedure for correcting rotational malalignment, but that they should be more cautious about its indications.Level of Evidence: Level IV.

Decreased femoral trochlea axial orientation corrected by derotational distal femur osteotomy in patients with patellar dislocation yields satisfactory outcomes

Li,

Chen,

Huo

et al. 2024

Self Cite

PurposeThe femoral trochlea axial orientation has been shown to be a better predictor of patellar dislocation than the femoral anteversion angle. However, no study has investigated the importance of the femoral trochlea axial orientation in the surgical treatment of patellar dislocation. It is aimed to explore the pathological threshold of the femoral trochlea axial orientation and its guiding implications for surgical interventions in the study.MethodsSixty‐four patients with patellar dislocation and 64 controls were included for measurement of the femoral trochlea axial orientation. The ability to predict the patellar dislocation and the pathologic threshold of the femoral trochlea axial orientation were evaluated using the receiver operating characteristic curve. One hundred patients with medial patellofemoral ligament reconstruction and 25 patients with derotational distal femur osteotomy were divided into two groups based on the femoral trochlea axial orientation cut‐off value and their postoperative knee functions, and patellar tilt angles were compared.ResultsThere were significant differences in the femoral trochlea axial orientation (60.8 ± 7.9 vs. 67.8 ± 4.6, p < 0.05) between patients with patellar dislocation and the normal population. The sensitivity and specificity of the femoral trochlea axial orientation were 0.641 and 0.813, respectively, at the femoral trochlea axial orientation smaller than 63.8°. Amongst patients having had isolated medial patellofemoral ligament reconstruction with decreased femoral trochlea axial orientation, knee function was poorer after surgery. The prognosis of patients with the femoral trochlea axial orientation correction in derotational distal femur osteotomy was better than that for patients without correction.ConclusionsThe femoral trochlea axial orientation had good predictive efficiency for patellar dislocation. Isolated medial patellofemoral ligament reconstruction is not sufficiently effective for patients with patellar dislocation and decreased femoral trochlea axial orientation. Patients with a decreased femoral trochlea axial orientation can have better surgical outcomes after correction by derotational distal femur osteotomy.Level of EvidenceLevel III.