Good outcomes of modified Grammont and Langenskiöld technique in children with habitual patellar dislocation.

PURPOSE: In this study, the functional mid-term outcomes of the modified Grammont and Langenskiöld technique was assessed in skeletally immature patients with habitual patellar dislocation, with emphasis on knee function, pain, and other possible post-surgical complications. This is the first study concerning the application of the modified Grammont and Langenskiöld technique in habitual patellar dislocations. METHODS: This retrospective cohort study considered 10 patients (15 knees), ranging from 7 to 11 years old, who underwent the modified Grammont and Langenskiold procedure between 2015 and 2018. History of dislocation, patellar stability and range of motion (ROM) were analysed. To assess functional improvement and knee pain, the Kujala Anterior Knee Pain Scale and KOOS-Child Knee Survey were used before and after surgical treatment. RESULTS: No history of dislocation was noted after surgical treatment. All 15 knees showed full ROM. There were no signs of genu recurvatum and no length discrepancies were found. The subjective assessment revealed significant improvement in the scores of the KOOS-Child questionnaire in all five sections (p < 0.001), as well as in The Kujala Anterior Knee Pain Scale (p = 0.001). CONCLUSION: The modified Grammont and Langenskiöld technique yields remarkable results in terms of knee stability and knee function, while decreasing recurrence risk and intensity of pain in patients with challenging cases of patellofemoral joint dislocation. This surgical technique is most effective in cases where the patella remains dislocated continuously; however, it may also be used in immature patients with recurrent instability. LEVEL OF EVIDENCE: IV.

Is acetabular dysplasia and pelvic deformity properly interpreted in patients with congenital femoral deficiency? A 3D analysis of pelvic computed tomography.

PURPOSE: The aim of this study is to assess the pelvis's morphology and spatial orientation of the acetabulum, and their relation to the severity of Congenital Femoral Deficiency (CFD) using 3D imaging. Defining these pathologies is crucial for adequate surgical correction. METHODS: The shape and structure of the acetabulum and pelvis were evaluated in 14 children with unilateral CFD via 3D computed tomography (CT) scans, and then analysed with geometric morphometrics (Procrustes ANOVA). The association between pelvic directional asymmetry and CFD classifications (Aitken, Paley) was assessed. The affected acetabulum's orientation was compared to the non-affected side, and the variability of orientation in different CFD types was evaluated (bivariate correlation). RESULTS: The hemipelvis with CFD is characterized by a smaller acetabulum, a laterally curved ischium and a less upright ilium (p < 0.001). Multivariate regressions revealed a greater level of pelvis asymmetry in more severe types of CFD (p < 0.001). The acetabulum orientation assessment showed a significant decrease in mean anteversion (1.3°) and inclination (9.6°) angle, when compared to the non-affected side (26°and 17.1° respectively; p < 0.001). CONCLUSIONS: The affected side of the pelvis is considerably smaller and more deformed, and this should be considered during limb lengthening. The acetabulum presents with significant dysplasia due to its severe retroversion and steepness (superoposterior distortion). This should not be interpreted as a simple wall deficit, but as a complete acetabular misalignment (often misinterpreted in 2D imagery). Using transiliac osteotomies (e.g. Dega, Salter) is debatable due to abnormal acetabular orientation (superoposterior malalignment). Therefore, alternative options, e.g. San Diego or triple pelvic osteotomy, should be considered.