Change in intersegmental foot and ankle motion after a high tibial osteotomy in genu varum patients.

High tibial osteotomy (HTO) is a well-established treatment for medial compartment knee osteoarthritis (OA), which shifts the weight-bearing axis from the medial to the lateral side of the knee. As the adjacent ankle joint may be directly affected by the change in biomechanics, this study aimed to evaluate the change in the intersegmental foot and ankle motion after HTO in patients with genu varum. The study included 24 patients who underwent HTO, and 48 older healthy participants as a control group. Segmental foot kinematics were evaluated using a 3D multisegment foot model, and gait data of temporal and spatial parameters were obtained. After HTO, normalized stride length significantly increased with a tendency for increases in gait speed. In hallux kinematics relative to the forefoot, the sagittal motions of both the patients and the control group were similar throughout the majority of the gait cycle. In forefoot kinematics relative to the hindfoot, the pre-HTO state revealed significant pronation throughout the gait cycle, while the post-HTO state showed a similar position and motion to the control group. In hindfoot kinematics relative to the tibia, coronal motions of the pre-HTO state showed supination throughout the gait cycle, while supination during the stance phase decreased after HTO. Genu varum patients with medial compartment knee OA showed different gait parameters and intersegmental motion during gait when compared with age- and gender-matched controls. The effect of HTO was demonstrated by the normalization of midfoot compensation in patients with genu varum.

Rotational kinematics differ between mild and severe valgus knees in total knee arthroplasty.

BACKGROUND: There is no consensus regarding femorotibial rotational kinematics in total knee arthroplasty (TKA) for valgus knee deformity. Additionally, whether the degree of valgus deformity influences intraoperative rotational kinematics and postoperative clinical scores remains unclear. The objectives of this study were to investigate whether the valgus angle is associated with intraoperative rotational kinematics in TKA for valgus knee deformity and to examine the relationship between rotational kinematics and postoperative clinical results. MATERIALS AND METHODS: A total of 24 knees with valgus deformity for TKA were included in this study and were divided into two groups depending on the femorotibial angle (FTA); there were 11 knees in the severe valgus group (FTA < 160°) and 13 knees in the mild valgus group (FTA ≥ 160°). Intraoperative femorotibial rotational kinematics from knee extension to flexion were evaluated using an image-free navigation system and postoperative clinical results (range of motion and subjective outcomes) were evaluated 1 year postoperatively. All parameters were compared between the two groups. RESULT: Mild valgus knee showed tibial internal rotation during knee flexion before implantation, whereas severe valgus knee showed tibial external rotation during knee flexion before implantation. The postoperative flexion angle was positively correlated with the tibial internal rotation angle after implantation in the mild valgus group only. CONCLUSION: Intraoperative rotational kinematics before implantation differed between mild and severe valgus knee deformity in TKA. Intraoperative tibial rotation influenced the postoperative knee flexion angle in mild, but not severe, valgus knee deformity. Ideal postoperative rotational kinematics may be different between the two groups and the difference may be taken into consideration in implant selections and surgical techniques.

Association between changes in knee load and effusion-synovitis: evidence of mechano-inflammation in knee osteoarthritis using high tibial osteotomy as a model.

OBJECTIVE: Although mechanically-induced inflammation is an appealing explanation linking different etiologic factors in osteoarthritis (OA), clinical research investigating changes in both biomechanics and joint inflammation is limited. The purpose of this study was to evaluate the association between change in surrogate measures of knee load and knee effusion-synovitis in patients with medial compartment knee OA undergoing high tibial osteotomy (HTO). METHODS: Thirty-six patients with medial compartment knee OA and varus alignment underwent 3D gait analysis and 3T magnetic resonance imaging (MRI) preoperatively and 1 year after medial opening wedge HTO. Primary outcome measures were the change in the external knee adduction moment impulse during walking and change in knee suprapatellar effusion-synovitis volume manually segmented on MRI by one blinded assessor. RESULTS: Mean (SD) knee adduction moment impulse [24.0 (6.5) Nm•s] and knee effusion-synovitis volume [8976.7 (8016.9) mm3] suggested substantial preoperative medial knee load and inflammation. 1-year postoperative changes in knee adduction moment impulse [-10.1 Nm•s (95%CI: -12.7, -7.4)], and knee effusion-synovitis volume [-1856 mm3 (95%CI: -3830, 117)] were positively correlated [r = 0.60 (95% CI 0.34, 0.78)]. Simple linear regression suggested a 448 mm3 (95%CI: 241, 656) reduction in knee effusion-synovitis volume per 1 Nm•s reduction in knee adduction moment impulse. Change in knee adduction moment impulse explained 36% (R2 = 0.36) of the variance of change in knee effusion-synovitis volume. CONCLUSIONS: Reduction in medial knee load is positively associated with reduction in knee inflammation after HTO, suggesting the phenomenon of mechano-inflammation in patients with knee OA.

Genu varum and football participation: Does football participation affect lower extremity alignment in adolescents?

BACKGROUND: Genu varum is one of the most common anatomical variations of knee alignment which is considered a risk factor for anterior knee pain and anterior cruciate ligament injury among football players. Considering that millions of children participate in high-level football training, the purpose of this study was to determine the genu varum development in adolescent football players and non-athlete peers. The hypothesis of this study was that genu varum incidence was higher in adolescent football players compared with non-athletic peers. METHODS: The design was a cross-sectional study. Two-hundred and thirty-seven male football players (FG) and aged-matched and anthropometrically similar non-athletes (CG) were recruited into the study. The quadriceps angle and intercondylar-intermalleolar distance were measured to evaluate the leg alignment. The distance between the medial edges of the condyles and malleoli was measured in millimeters using a digital caliper while angle measurements were performed using a photographic technique in a standing position. To analyze the variables, comparison, correlation and regression statistical tests were performed. RESULTS: The intercondylar-intermalleolar distance and quadriceps angle values were significantly higher in FG than CG in all ages. In FG, a very strong correlation was found between number of training years and the intercondylar-intermalleolar distance. The prevalence of genu varum was markedly higher in FG than CG (~37% vs. 2%, respectively) based on intercondylar-intermalleolar distance. CONCLUSION: This study determined that the prevalence of genu varum and abnormal quadriceps angles in adolescent football players is significantly higher compared with their non-athletic peers.

Clinical Significance of Combined Weight-Bearing and Non-Weight-Bearing Positions and MRI Examination in Evaluating Genu Varus.

OBJECTIVE: To siscuss the clinical significance of the early diagnosis of knee varus and knee osteoarthritis with the combination of negative position and non-negative position and radiography. METHODS: One hundred and eighty patients whose femorotibial angles <182° (genu varus positive) measured by X-ray at the weight-bearing position and femorotibial angles ≥182° (genu varus negative) measured by X-ray at the non-weight-bearing position were selected as the sample group from those patients who received knee joint Magnetic resonance imaging (MRI) examination from July 2015 to July 2017. One hundred and eighty patients whose femorotibial angles ≥182° (genu varus negative) measured at both the weight-bearing position and the non-weight-bearing position were selected as the control group. Femorotibial angles of both groups were respectively measured, to respectively compare and analyze the effect of non-weight-bearing false-negative genu varus on the occurrence and severity of injury of medial meniscus and femorotibial articular cartilage. The two groups of patients had no previous history of knee surgery, and no lower limb fracture, inflammation, tumor, metabolic bone disease, or congenital disease. RESULTS: The weight-bearing tibiofemoral angles of the non-weight-bearing false-negative genu varus group and the negative genu varus group (180.998° ± 0.589°) were lower than the non-weight-bearing tibiofemoral angles (182.501° ± 0.290°), and they were positively correlated (t = -15.048, P < 0.01). The non-weight-bearing knee varus medial meniscus incidence of false- negative group. Medial meniscus injury that occurred in the sample group were 86.7% (156/180) in the anterior horn, 91.7% (165/180) in the body, 88.3% (159/180) in the posterior horn. Medial meniscus injury that occurred in the control group were 46.7% (84 /180) in the anterior horn, 40.6.3% (73/180) in the body, 43.3% (78/180) in the posterior horn. The incidence of degenerative groups, the differences were statistically significant. The incidence and severity of injury were as follows: medial meniscus anterior horn (χ2 = 41.966, P = 0.000), body (χ2 = 104.94, P = 0.000), posterior horn (χ2 = 81.025, P = 0.000). The incidence and severity of medial meniscus injury in the non-weight-bearing knee varus false negative group was higher than in the control group. The non-weight-bearing knee varus false-negative group medial tibiofemoral articular cartilage degeneration rate was 95.0% (171/180); in the control group, medial tibiofemoral articular cartilage degeneration was 65.1% (117/180). Two medial tibiofemoral articular cartilage degeneration incidence were statistically significant. The incidence and severity of injury were as follows: medial tibiofemoral articular cartilage (χ2 = 50.625, P = 0.000). The incidence and severity of medial tibiofemoral articular cartilage injury in the non-weight-bearing knee varus false negative group was higher than in the control group. CONCLUSION: The combined weight-bearing position and non-weight-bearing position imaging examination for diagnosing the non-weight-bearing false-negative genu varus patients at an early date is of significant importance to the early diagnosis and treatment of knee osteoarthritis.

Squat Muscle Activation Patterns with Hip Rotations in Subjects with Genu Varum Deformity.

The purpose of this study was to compare muscle activation during the squat with different hip rotations (neutral, 15, 30, and 45° of internal and external hip rotation) in subjects with and without Genu Varum deformity deformity. Surface electromyography were recorded from 32 men with (n=16) and without (n=16) Genu Varum deformity. In the Genu Varum deformity group, the squats with 30, 45 and 15° of internal rotations of the hip showed significantly greater gluteus medius activation as compared to other positions. Moreover, the tensor fascia lata activity increased with greater external rotation of the hip, and significantly more than hip internal rotations (p<0.05). For vastus medialis and vastus lateralis, both hip internal and external rotation showed a significantly greater activation compared to the neutral hip positions (p<0.05). There were significant differences in the gluteus medius:tensor fascia lata activity ratio (p=0.001) and the vastus medialis: vastus lateralis activity ratio (p=0.001) between the different hip positions in the Genu Varum deformity and healthy groups. These results demonstrate that muscle activation patterns varied significantly with the position of different hip rotation in both groups. Those with Genu Varum deformity may use this information to aid in an injury prevention strategy by choosing squat positioning that favorably alters muscle activation patterns.

The influence of hip rotations on muscle activity during unilateral weight-bearing exercises in individuals with and without genu varum: A cross-sectional study.

OBJECTIVES: Hip rotation can influence gluteus medius (Gmed) muscle activity in individuals with genu varum (GV). This study examined different hip rotation positions on muscle activity during unilateral weight-bearing exercises in individuals with and without GV. DESIGN: Cross-sectional. SETTING: Outpatient physical therapy center. PARTICIPANTS: Forty-six physically active males, divided between control (n = 23) and GV groups (n = 23). MAIN OUTCOME MEASURES: Surface electromyography measured Gmed and tensor fascia latae (TFL) activity during pelvic drop (PD) and wall press (WP) exercises with different hip rotations. RESULTS: In the control group, WP with external rotation produced greater Gmed/TFL activity compared to other rotation positions. No difference was found for Gmed/TFL with PD in controls. In the GV group, Gmed activity increased with internal rotation in PD and WP; TFL activity increased only with external rotation in WP. Internal hip rotation produced higher Gmed/TFL activity than other positions in the GV group during both exercises. Greater Gmed/TFL activity was observed in the control group than GV during PD with external rotation, and WP with neutral positioning and external rotation. CONCLUSIONS: WP with external rotation in controls, and PD and WP with internal hip rotation in subjects with GV, are effective exercises to optimize GMed/TFL activity.

Long-term effects of shoe mileage on ground reaction forces and lower limb muscle activities during walking in individuals with genu varus.

BACKGROUND: Shoe mileage is an important factor that may influence the risk of sustaining injuries during walking. The aims of this study were to examine the effects of shoe mileage on ground reaction forces and activity of lower limb muscles during walking in genu varus individuals compared with controls. METHODS: Fifteen healthy and 15 genu varus females received a new pair of running shoes. They were asked to wear these shoes over 6 months. Pre and post intervention, mechanical shoe testing was conducted and ground reaction forces and muscle activities of the right leg were recorded during walking at preferred gait speed. FINDINGS: Significant group-by-time interactions were found for shoe stiffness, antero-posterior and vertical impact peak. We observed higher shoe stiffness and lower impact peaks after intervention in both groups with larger effect sizes in genu varus. Significant group-by-time interactions were identified for vastus medialis (loading phase) and rectus femoris (loading and push-off). For vastus medialis, significant decreases were found from pre-to-post during the loading phase in the control group. Rectus femoris activity was higher post intervention during the loading and push-off phases in both groups with larger effect sizes in genu varus. INTERPRETATION: Our findings indicate that the observed changes in ground reaction forces are more prominent in genu varus individuals. Together with our findings on shoe stiffness, it seems appropriate to change running shoes after an intense wearing time of 6 months, particularly in genu varus individuals.

Clinical measurement of angular profile of the knee and correlation with intermalleolar distance in children in Enugu metropolis.

BACKGROUND: Angular deformities of the lower limbs are commonly encountered deformities in pediatric orthopedic clinics. The values of the tibiofemoral angle undergoes changes as the child grows and these changes are self-limiting. The aim of the study is to establish the normal variation of knee angles of children between 2 and 12 years of age in Enugu metropolis and to establish any correlation between the knee angles and the intermalleolar distances (IMDs). SUBJECTS AND METHODS: This study was done on 630 school children in Enugu metropolis between the age groups of 2 and 12 years. Multistage sampling was used in the study. The tibiofemoral angles and intermalleolar/intercondylar distances were measured. RESULTS: The maximum tibiofemoral angle from this study was 7.6° ± 2.4° and the age corresponding to this value was 4 years. Only 23 subjects (3.5%) had varus knee angle. The values of the mean tibiofemoral angle and IMDs plateaued from 8 to 12 years. There was a significant positive correlation between average knee angle and IMD (r = 0.785, P < 0.001). CONCLUSION: The physiological changes in the knee angle (tibiofemoral) follow a similar pattern as established in the literature and there was positive correlation between IMD and the tibiofemoral angle.

The Effects of Surgical Technique in Total Knee Arthroplasty for Varus Osteoarthritic Knee on the Rotational Alignment of Femoral Component: Gap Balancing Technique versus Measured Resection Technique.

Few studies have compared the accuracy of femoral component rotation in the measured resection technique according to the preoperative computed tomography (CT) and gap balancing technique. The aim of this study was to evaluate whether there is a difference in accuracy and outlier incidence of femoral component rotation between gap balancing and measured resection techniques with or without preoperative CT and to evaluate the difference in patellofemoral alignment on simple radiographs and clinical outcomes. In this retrospective study, we evaluated femoral component rotation angle on the clinical and surgical transepicondylar axis (FCRA-cTEA and FCRA-sTEA, respectively), patellar tilt angle, lateral patellar displacement, and patient-reported outcomes in the gap balancing technique (Group 1) and in the measured resection technique without (Group 2) and with (Group 3) preoperative CT. A total of 163 total knee arthoplasty (TKA) replacements were included in this study. Average FCRA-cTEA was -3.4 ± 2.6, -2.8 ± 2.1, and -1.8 ± 2.3 degrees in groups 1 to 3, respectively (p = 0.002). Average FCRA-sTEA was -0.2 ± 2.7, 0.5 ± 2.4, and 1.5 ± 2.1 degrees, respectively (p = 0.001). In an outlier analysis that evaluated femoral component rotation using cTEA as reference, no significant difference was observed between the three groups (40.8, 37.3, and 23.7%, respectively, p = 0.133). When sTEA was used as a reference, groups 1 and 3 showed an outlier incidence of 8.2 and 8.5%, respectively, whereas this incidence was as high as 23.5% in group 2 (p = 0.030). No statistically significant group difference in patellofemoral alignment and patient-reported outcome was observed. In the measured resection technique with preoperative CT, the femoral component was externally rotated approximately 1 degree more than in the gap balancing or measured resection technique without preoperative CT. However, the difference in FCRA among the three techniques was not linked to the difference in patellofemoral alignment or patient-reported outcomes.

Relationships between Morphological Changes of Lower Limbs and Gender During Medial Compartment Knee Osteoarthritis.

OBJECTIVES: To evaluate the dynamic changes of key morphology indicators of the lower extremities in the coronal plane with progressing medial compartment knee osteoarthritis (KOA) with an emphasis on gender-dependent regional differences. METHODS: The radiographs of patients with non-traumatic knee pain and varying degrees of genu varus were reviewed. Radiographs were studied in 1538 lower limbs of 883 consecutive patients who visited our hospital from January to July 2017; all patients had long-standing anteroposterior image-splicing radiographs taken of their lower limbs. Morphological indicators of bones and joints that can change the alignment of lower limbs or reflect cartilage wear and soft-tissue relaxation were selected and measured with the help of picture archiving and communication systems. After comparing the data of different genders, the data of males and females was separated into three age groups, <40 years, 40-60 years, >60 years respectively, and then compared among age groups using the Kruskal-Wallis and Mann-Whitney U tests. Scatterplots of age and all the measurements were drawn to determine the strength of the relations. The Pearson correlation test was performed to reveal correlations of measurements and age. RESULTS: Femoral bowing angle (FBA) and joint line convergence angle (JLCA) have obvious differences between different genders (P = 0.001, 0.000, respectively). This suggests that females have greater femoral curvature and joint space angle than males. Significant differences were found in hip-knee-ankle angle (HKA), FBA, distal femoral valgus resection angle (DFVRA), medial proximal tibial angle (MPTA), JLCA, and minimum joint space width (min-JSW) by age groups in females (P = 0.000, 0.000, 0.000, 0.000, 0.003, 0.002, respectively). The difference of mechanical medial distal femoral angle (mMDFA) was significant with P values less than 0.05 deemed significant (P = 0.030). Significant correlations were found between age and all measurements (r = -0.166, 0.253, 0.270, -0.147, 0.089, -0.105, -0.076, respectively, P < 0.01). Whereas, the difference in min-JSW by age group was the only significant one in males (P = 0.001), and no significant correlation was found between age and measurements (r = -0.107, 0.041, 0.134, -0.067, 0.079, -0.134, -0.098, respectively, P > 0.01). CONCLUSIONS: As KOA progressed, both dynamic deformation of lower extremities and degeneration of articular cartilage could be found in females, while no obvious dynamic deformations were found in males. Dynamic deformation of lower extremities was the important feature and the major causative factor of KOA in females.

Improving the accuracy of tibial component placement during total knee replacement in varus knees with tibial bowing: A prospective randomised controlled study.

BACKGROUND: Lateral tibial bowing leads to varus placement of the tibial component during total knee replacement in varus knees. Lateralised tibial jig placement can improve the accuracy of the tibial cut. METHODS: A total of 227 patients (300 knees) undergoing total knee replacements were randomised into two groups. In the study group, the point of intersection of the distal tibial diaphyseal line at the tibial plateau drawn on long films was represented by zones. Knees with femoral bowing >5° (28%) were excluded. Tibial jig placement on the proximal tibia was lateralised according to the zones. In the control group, the mid-point of the tibial plateau was taken as a reference. Femoral and tibial bowing, postoperative limb alignment and component placement were assessed. RESULTS: Of the 216 knees that were studied, 106 were in the study group and 110 in the control group. Bowing ≥3° had a significant positive correlation with lateralisation of the proximal tibial reference (p < 0.001). The Incidence of tibial bowing ≥3° was 57.33%. The mean postoperative hip-knee-ankle (HKA) angle was 178.31 ±â€¯2.88° and 176.53 ±â€¯2.88° (p < 0.001), whereas the mean medial proximal tibial angle (MPTA) was 89.91 ±â€¯1.42° and 88.79 ±â€¯1.72° (p < 0.001) in the study and control groups, respectively. Considering bowed tibiae alone, HKA angle and MPTA in the study group were 178.08 ±â€¯2.81° and 89.72 ±â€¯1.39° compared with 175.88 ±â€¯2.87° and 88.38 ±â€¯1.38° in the control group (p < 0.001). CONCLUSION: There is a high incidence of tibial bowing in varus knees. Lateralised tibial jig placement improved tibial component placement and postoperative limb alignment in total knee arthroplasty in varus knees with tibial bowing.

Kinematically Aligned TKA Aligns the Ankle Joint Line Closer to Those of the Native Ankle than Mechanically Aligned TKA in Bipedal Stance.

Mechanically aligned total knee arthroplasty (MATKA) aims to make alignment of the hip, knee, and ankle straight unexceptionally. However, emerging evidence suggests that unexceptional straightening the mechanical axis of the lower limb may lead to clinical and radiological problems of the ankle joint. By contrast, kinematically aligned total knee arthroplasty (KATKA) strives to restore the articular surface of the prearthritic knee. In this study, we examined results from KATKA and MATKA to determine which surgery restores the ankle joint orientation closer to the native ankle joint in bipedal stance and hypothesized that KATKA, rather than MATKA, would be more effective. Data from long-leg standing radiographs of 60 healthy adults (control group, n = 120 knees), patients who underwent MATKA (n = 90 knees), and patients who underwent KATKA (n = 90 knees) were retrospectively reviewed. The hip-knee-ankle angle, orientation of the tibial plafond and the talar dome relative to the ground (G-plafond and G-talus, respectively), and orientation of the plafond relative to the mechanical axis of the limb (M-plafond and M-talus, respectively) were measured and analyzed for comparison. Results show that bipedal stance alignment in patients who underwent KATKA (G-plafond: -0.65 ± 3.03 and G-talus: -1.72 ± 4.02) were not significantly different to native ankle joint alignment indicated by the control group. Compared with the native ankle joint measured in the control group (G-plafond: -0.76 ± 2.69 and G-talus: -1.30 ± 3.25), the tibial plafond and talar dome significantly tilted laterally relative to the ground in ankle joints after MATKA (G-plafond: -2.32 ± 3.30 and G-talus: -2.97 ± 3.98, p = 0.001 and p = 0.004, respectively). Thus, postoperative ankle joint line orientation after KATKA was horizontal to the floor and closer to that of native ankle joints than those after MATKA. The level of evidence is Level III.

Impact of preoperative varus deformity on postoperative mechanical alignment and long-term results of "mechanical" aligned total knee arthroplasty.

PURPOSE: Preoperative varus deformity may affect postoperative mechanical alignment and outcomes of total knee arthroplasty (TKA). In this study, we aimed to determine whether (1) greater degrees of preoperative varus deformity increase the incidence of varus-aligned TKAs and (2) residual varus alignment improves the long-term survival rate in TKAs with preoperative varus deformity. METHODS: We retrospectively reviewed 905 primary TKAs for varus-type osteoarthritis from November 1998 to June 2009. The mean follow-up was 8.23 years (±3.47 years). We measured pre- and postoperative mechanical hip-knee-ankle axis angle (HKA) on full-length standing radiographs to assess the severity of preoperative varus deformities, defined as mild (0°15°). Postoperative alignment was divided to four groups: valgus (HKA<-3°), neutral (-3°≤HKA≤3°), mild varus (3°6°). We performed survival analysis in all cases for mechanical failure. RESULTS: Varus-aligned TKAs increased proportionally to increasing preoperative varus deformity (p<0.001). The survival rate showed no significant difference according to the preoperative varus deformity (p=0.147). However, the survival time for postoperative neutral alignment (16.13±0.10 years, 95% CI 15.94-16.33 years) was longer than the survival time for mild varus (15.32±0.35 years, 95% CI 14.64-16.00 years) and severe varus (13.38±0.53 years, 95% CI 12.35-14.42 years) alignment (p<0.001). CONCLUSION: Postoperative varus malalignment appears to increase proportionally to the severity of preoperative varus deformity. Also, postoperative neutral alignment results in longer TKA survival time than residual varus alignment. LEVEL OF EVIDENCE: III, Retrospective comparative cohort study.

A comparative evaluation of tibial metaphyseal-diaphyseal angle changes between physiologic bowing and Blount disease.

The purpose of this study was to estimate the rate of spontaneous improvement in tibial metaphyseal-diaphyseal angle (TMDA) in physiologic bowing in comparison to that in Blount disease and to provide reference values of TMDA for monitoring patients with highly suspected to have Blount disease.We retrospectively reviewed patients with physiologic bowing meeting the following criteria:(1) TMDA greater than 9° before 36 months of age at initial evaluation;(2) two or more standing long bone radiographs available; and(3) follow-up conducted up to resolution of deformity.Patients with Blount disease had(1) more than 2 standing long bone radiographs obtained before 36 months of age and(2) underwent no treatment during the period in which these images were obtained.TMDA measurements were obtained from 174 patients with physiologic bowing and 32 patients with Blount disease. Rates of TMDA improvement were adjusted by multiple factors using a linear mixed model, with sex and laterality as fixed effects and age and individual patients as the random effects.In the physiologic bowing group, TMDA improved significantly, by 3° per 6 months and by 6° per year. Changes in TMDA were not significant in the Blount disease group.Knowing the rate of TMDA change can be helpful for physicians seeking to monitor infants with suspected as having Blount disease with a high TMDA and to avoid unnecessary repeat radiographic evaluations.

Residual varus alignment after total knee arthroplasty increases knee adduction moment without improving patient function: A propensity score-matched cohort study.

BACKGROUND: Targeting residual varus alignment in total knee arthroplasty may be functionally beneficial to preoperative varus patients. METHODS: Bilateral TKA patients were enrolled. According to the postoperative hip-knee-ankle axis, patients were allocated into residual varus (3°â€¯±â€¯1°) alignment group or neutral (0°â€¯±â€¯1°) alignment group. Then, 1:2 propensity score matching was used to match preoperative variables. Finally, matched neutral (n = 45) and varus groups (n = 32) were followed-up for two years and compared. The primary outcome was the Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC). Secondary outcomes were range of motion (ROM), Knee Society knee score and function score, spatiotemporal gait parameters, dynamic alignment, knee flexion angle, knee adduction moment (KAM) and internal knee extension moment. RESULTS: At two years after surgery, the mean difference of WOMAC score was 0.3 (95% CI, [-3.1, 3.7]) between the two groups. All secondary outcomes, except KAM and dynamic alignment, showed no significant difference between the two groups. Residual varus alignment group showed increased KAM and maximum KAM was 19% higher (P = 0.006). CONCLUSIONS: Residual varus alignment showed no clinical benefits, and both groups of patients had a functionally identical knee gait biomechanics, except for increased KAM and varus alignment. The authors consider that even in patients with varus alignment, the first principle is still achieving neutral alignment, which is helpful for reducing the KAM. LEVEL OF EVIDENCE: III, retrospective cohort study.

Comparison the time to stabilization and activity of the lower extremity muscles during jump-landing in subjects with and without Genu Varum.

BACKGROUND: Knee muscles activity changes from Genu Varum deformity(GVD), may cause this individual more exposed to lower extremity injuries especially in high-risk activities like landing. OBJECTIVE: The aim of this study was to compare the activity of the lower limb stabilizer muscles during jump-landing and time to stabilization(TTS) in subjects with and without GVD. METHOD: A total of 44 men (group 1, with GVD n = 22 and group 2, without GVD n = 22); with mean age = 17.6 ± 3.12 years, height = 178.2 ± 5.39 cm, mass = 80.39 ± 8.3 kg) participated in this study. Subjects were asked to do a jump-landing task and Quadratus Lumborum(QL), Gluteus Maximus(GMax), Gluteus Medius(GMed), Biceps Femoris (BF), Semitendinosus, and Medial Gastrocnemius(MG) muscles activity was recorded. Also, changes in the amount of ground reaction force(GRF) were used to an indicator for TTS. RESULTS: Our results showed that subjects with GVD had increased QL activity before(P = 0.008) and after(P = 0.017) landing. But, these subjects had a decreased activity of GMed compared to the healthy ones before(P = 0.033) and after(P = 0.005) landing. but there was no statistically significant difference before landing in gluteus maximus(P = 0.252), biceps femoris(P = 0.613), semitendinosus(P = 0.313), and medial gastrocnemius(P = 0.140) muscles and after landing in gluteus maximus (P = 0.246), biceps femoris(P = 0.512), semitendinosus(P = 0.214), and medial gastrocnemius(P = 0.209) muscles between the two groups. Also, the TTS was higher in subjects with GV than healthy ones in the Resultant Vector TTS (P = 0.015) and medial-lateral(P = 0.013) directions. CONCLUSIONS: The altered activity of the QL and GMed, in subjects with GVD may indicate instability of the spinal column, pelvis and hip during jump-landing task. Although the GVD is referred to the frontal plane deformity, the results showed that this complication might affect stability in other motion planes.

Bowlegs and Intensive Football Training in Children and Adolescents.

BACKGROUND: In many countries around the world, football (association football, or "soccer" predominantly in North America) is the sport most commonly played by children and adolescents. It is widely thought that football players are more likely to develop genu varum (bowlegs); an association with knee arthritis also seems likely. The goals of this systematic review and meta-analysis are to provide an overview of the available evidence on genu varum after intensive soccer training in childhood and adolescence, and to discuss the possible pathogenetic mechanisms. METHODS: We systematically searched the PubMed, Medline, Embase, and Coch- rane Library databases for studies of the relation between leg axis development and intensive football playing during the growing years. RESULTS: Controlled studies employing the intercondylar distance (ICD) as the target variable were evaluated in a meta-analysis, with the mean difference as a measure of effect strength. This meta-analysis included 3 studies with a total of 1344 football players and 1277 control individuals. All three studies individually showed a signifi- cant difference in the mean ICD values of the two groups. The pooled effect esti- mator for the mean difference was 1.50 cm (95% confidence interval [0.53; 2.46]). Two further studies that could not be included in the meta-analysis had similar con- clusions. Asymmetrical, varus muscle forces and predominantly varus stress on the osseous growth plates neighboring the knee joint, especially during the prepubertal growth spurt, seem to be the cause of this phenomenon. CONCLUSION: Intensive soccer playing during the growing years can promote the devel- opment of bowlegs (genu varum) and, in turn, increase the risk of knee arthritis. Phy- sicians should inform young athletes and their parents of this if asked to advise about the choice of soccer as a sport for intensive training. It cannot be concluded, however, that football predisposes to bowlegs when played merely as a leisure activity.

Effect of kinesio taping on lower limb joint powers in individuals with genu varum.

OBJECTIVE: Therapeutic lateral knee joint muscle taping potentially offers a low-risk, economical and effective alternative for the clinical treatment of light to moderate knee overload, due to misalignment in patients with genu varum. In this study, we aimed at investigating the immediate effect of lateral knee joint muscular kinesio taping on lower limb joint powers, during the stance phase of walking, in individuals with genu varum. METHODS: Fifteen male subjects with genu varum misalignment (age: 24.2±3.7 years) participated in the study. Subjects performed three walking trials without, and three with, biceps femoris and vastus lateralis kinesio taping. The three-dimensional position coordinate data of reflective markers were collected at 100 Hz using a six-cameras Vicon system (Motion Analysis Corp., UK). Additionally, two Kistler force plates (Kistler AG, Winterthur, Switzerland) were used to record the Ground Reaction Forces (GRF) components at 1000 Hz during stance phase of walking. A three-way ANOVA with post-hoc testing (using paired samples Student's t-test with Bonferroni correction) was performed to compare the power values of lower limb joints before and after the use of KT. RESULTS: With kinesio taping, we observed that the average negative power increased at the ankle level in dominant limb, (P<0.05, 10-20% of gait cycle, GC), and at the knee level in both limbs (10-20% and 60-80% GC). Further, average negative power of the non-dominant knee joint (80-100% GC) and positive power of the non-dominant hip joint (60-80% GC) significantly reduced (P<0.05) in kinesio taping condition. CONCLUSION: The biomechanical analysis of joint power during walking using kinesio taping provided essential information about the possible mechanisms involved in gait analysis with this intervention in adults with genu varus.

Knee alignment in adolescents is correlated with participation in weight-bearing sports.

PURPOSE: Weight-bearing sports might influence the alignment of the lower extremities during growth. The relationship between participation in weight-bearing sports and the alignment of the lower extremities in adolescents has not been adequately studied yet. The aim of the study was to investigate whether sports participation during growth in early adolescence is correlated with the development of genu varum. METHODS: The design was a correlation study in which 1008 (564 boys, 444 girls) healthy adolescents (from 12 to 19 years of age) were recruited in secondary schools. The alignment of the knee was determined by measuring the intercondylar (IC) and intermalleolar (IM) distance using a specially designed instrument and an inside calliper. The degree of sports participation of the participants was determined by a questionnaire in which they were asked how many hours a week they participated in sports and for how many years in total. RESULTS: The results of this study revealed a significant correlation between participation in weight-bearing sports and genu varum in each of three different age groups, both for boys and girls. CONCLUSION: Our results show that there is an association between the alignment of the knee joint and participation in weight-bearing sports during early adolescence.