Joint-line obliquity angle is significantly affected by hip abduction and adduction: A simulated analysis.

PURPOSE: Different methods for quantifying joint-line obliquity (JLO) have been described, including joint-line obliquity angle (JLOA), Mikulicz joint-line angle (MJLA) and medial proximal tibial angle (MPTA). The goal of the present study was to quantify the variation of JLOA based on the position of the hip. The hypothesis of our study is that JLO is significantly influenced by the abduction/adduction of the limb, unlike MJLA. METHODS: One hundred long-leg-weightbearing X-rays were used. At time 0 and after 30 days, two observers performed different measurements, including (1) distance between pubic symphysis and center of the femoral head, (2) distance between center of the femoral head and center of the ankle joint, (3) distance between center of the ankle and medial malleolus, (4) hip-knee-ankle angle, (5) MPTA, (6) lateral distal femoral angle, (7) joint-line congruency angle, (8) JLOA, (9) MJL and (10) angle between Mikulicz line and line perpendicular to the ground. The changes of the JLOA based on the position of the hip (abducted, neutral, bipedal stance adduction and monopodal stance adduction) were calculated with trigonometric formulas and with simulation on an orthopaedic planning digital software. RESULTS: The JLOA change between adducted and abducted positions was on average 12.8° (SD 0.9 mm). The MJL did not vary significantly based on hip position. CONCLUSIONS: The adduction/abduction of the lower limb has a considerable impact on JLOA. Methods like MJLA which are not affected by hip position should be preferred for JLO evaluation. LEVEL OF EVIDENCE: Diagnostic study, level III.

Transepicondylar distance measured on MRI can predict the length of the graft required for different anterior cruciate ligament reconstruction (ACLR) techniques useful for revision surgery.

BACKGROUND: The aim of this study is to find a correlation between linear measurements and the graft length required for different anterior cruciate ligament (ACL) revision techniques, to extract formulas to predict required graft length during the preoperative planning. METHODS: At time 0 and 30 days later, two observers measured eight linear distances on standard 2D knee magnetic resonance imaging (MRI), and nine curved distances on 3D MRI sequences, corresponding to different techniques for ACL revision, anatomic anterolateral ligament (ALL) reconstruction, and lateral extrarticular tenodesis (LET). Intra- and interobserver reliability was tested for 2D and 3D measurements. The correlation between 2D and 3D measurements was tested. The 2D measurements with highest repeatability and reproducibility, and with strongest correlation with 3D measurements were used to extract formulas to calculate the graft length from 2D values. RESULTS: Fifty MRIs acquired with both 2D and 3D sequences were used. The intra- and interobserver reliability of linear 2D measurement was high, with the transepicondylar distance (TD) showing the highest reproducibility and repeatability. The intra- and interobserver reliability of 3D measurements was lower than 2D, but acceptable for all measurements except for ALL reconstruction. The TD showed the strongest correlation with 3D measurements. The formulas extracted to calculate the graft length from the TD proved to be accurate. CONCLUSION: Accurate formulas were created to calculate the graft length needed for different ACL revision techniques and ALL reconstruction/LET techniques from TD. These formulas can be used during preoperative planning of ACL revision cases.

[Rupture of the anterior cruciate ligament in women]. / Lésions du ligament croisé antérieur chez la femme.

Rupture of the anterior cruciate ligament (ACL) is a frequent injury, and it affects women more often than men. The increased incidence in females was attributed to biological, anatomical, and mechanical differences when compared to males' counterparts. Hormones, menstrual cycle, and genetic factors are also implicated. Dynamic factor such as hip, knee and ankle biomechanics while jumping, landing, and cutting activities are established contributors to ACL rupture in females. Social and economic aspects both is sports and daily life are currently implicated in increased risk of injury and delayed return to sport. Therefore, they should be taken into consideration when studying ACL injury risk factors and when developing rehabilitation and prevention programs.

La rupture du ligament croisé antérieur (LCA) est fréquente et touche plus souvent les femmes que les hommes. L'incidence accrue chez les femmes a été attribuée à des différences biologiques, anatomiques et mécaniques. Les hormones, le cycle menstruel et les facteurs génétiques jouent aussi un rôle. Les facteurs dynamiques tels que la biomécanique de la hanche, du genou et de la cheville lors des activités de saut, d'atterrissage et de pivot sont des facteurs de risque prouvés de la rupture du LCA chez les femmes. Les aspects sociaux et économiques, tant dans le sport que dans la vie quotidienne, sont impliqués dans l'augmentation du risque de blessures et le retard du retour au sport. Ils doivent donc être pris en compte lors de l'étude des facteurs de risque de blessure du LCA et de l'élaboration de programmes de rééducation et de prévention.

Transepicondylar Distance Can Predict Graft and Tunnel Length for Different Pediatric Anterior Cruciate Ligament Reconstruction Techniques: A Magnetic Resonance Imaging Study.

PURPOSE: To find a correlation and mathematical formulas between a linear 2-dimensional (2D) magnetic resonance imaging (MRI) measurement around the knee and the length of the grafts and tunnels required for both all-inside-all-epiphyseal and Kocher-Micheli pediatric anterior cruciate ligament (ACL) reconstruction techniques. METHODS: At time 0 and 30 days after, 2 observers measured: (1) on standard 2D knee MRI, 7 linear distances, representing morphologic measurements, such as transepicondylar distance (TD), and (2) on 3-dimensional (3D) MRI, 5 curved distances, corresponding to Kocher-Micheli and all-epiphyseal ACL reconstruction techniques. Intra- and interobserver reliability was tested for all measurements. The correlation between 2D and 3D measurements was tested. The 2D measurement with highest repeatability and reproducibility and with strongest correlation with 3D measurements was used to extract formulas to calculate the tunnel and graft length for the 2 techniques. RESULTS: Seventy-six MRIs were used. The intra- and interobserver reliability of 2D measurement was high, with TD showing the highest reproducibility and repeatability. 3D measurements also showed good intra and inter-observer reliability. A linear correlation was found between 2D and 3D measurements, with TD showing the strongest correlation. TD was used to extract formulas to calculate graft or tunnel length for Kocher-Micheli and all-epiphyseal ACL reconstruction. All formulas were proven to be accurate. A reference chart was also created to be used in the surgical setting. CONCLUSIONS: With specific formulas, TD can be used to calculate the length of the tunnels, intra-articular portion and graft length for an all-inside all-epiphyseal pediatric ACL reconstruction and the length of the iliotibial band required for the Kocher-Micheli technique. CLINICAL RELEVANCE: The surgeon can use these formulas in pediatric ACL reconstruction preoperative planning, graft harvesting and tunnel drilling.

Joint Line Obliquity Does Not Affect the Outcomes of Opening Wedge High Tibial Osteotomy at an Average 10-Year Follow-up.

BACKGROUND: A significant number of high tibial osteotomies (HTOs) result in an overcorrected tibia and subsequent excessive lateral joint line obliquity (JLO). The correlation between excessive JLO and poor outcomes is controversial. PURPOSE: To evaluate the prognostic factors (including a pathological postoperative JLO) related with the outcomes of opening wedge HTO at 10 years of follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients undergoing HTO between 2004 and 2017 for medial osteoarthritis and with a postoperative hip-knee-ankle angle between 176° and 185° were included. Clinical evaluation included Knee Society Score (KSS; knee score and function score), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and visual analog scale for pain. Several mechanical and anatomic angles were measured pre- and postoperatively on long-leg weightbearing radiographs. Abnormal JLO was defined as a Mikulicz-joint line angle (MJL) ≥94° or a mechanical medial proximal tibial angle (mMPTA) ≥95°. Regression analysis was performed to evaluate the association between independent variables and each outcome. A Kaplan-Meier cumulative survival analysis was performed. RESULTS: A total of 92 knees in 76 patients were included. The mean age of the patients was 53.5 years (SD, 9.7 years), and the mean follow-up was 129.4 months (SD, 44.4 months). Increased JLO was associated with a significant preoperative varus deformity (small preoperative hip-knee-ankle angle), increased mechanical lateral distal femoral angle, increased joint line congruency angle, and increased knee-ankle joint angle. Male sex was associated with better WOMAC scores (P = .0277), and increased body mass index (BMI) was associated with inferior WOMAC scores (P = .0024). A good preoperative range of motion was associated with better knee score (P = .0399) and function score (P = .0366) on the KSS. An increased BMI was associated with inferior KSS function scores (P = .0317). MJL ≥94° and mMPTA ≥95° were not associated with inferior WOMAC or KSS outcomes. With indication to total knee arthroplasty as an endpoint, Kaplan-Meier analysis showed a survival rate of 98.7% at 5 years, 95.5% at 10 years, and 92.7% at 12 years. CONCLUSION: Increased lateral JLO (MJL ≥94° or mMPTA ≥95°) was not correlated with the clinical outcomes of opening wedge HTO at 10 years of follow-up.

High Tibial Osteotomy and Anterior Cruciate Ligament Reconstruction/Revision.

High tibial osteotomy (HTO) may be performed in association with anterior cruciate ligament (ACL) reconstruction/revision in patients with medial osteoarthritis, varus malalignment, and anterior instability. Furthermore, it may be performed in patients with varus alignment and increased posterior tibial slope (exceeding 12°), because it is related to an increased risk for ACL failure. There are different techniques to perform HTO, and consequently, a concomitant HTO and ACL reconstruction/revision. This article describes the indication, surgical techniques, and outcomes of concomitant HTO and ACL reconstruction/revision.