Relationships between reference lines altered during leg shape correction as requested by the patient

Introduction Patients who want their leg shape changed often identify the O- or X-shaped legs with varus or valgus deformity striving for ideally shaped legs as classified by A. A. Artemiev. The purpose of the study was to compare changes in the relationship between reference lines as mechanical axis deviation (MAD), mechanical medial proximal tibial angle (mMPTA), mechanical lateral distal tibial angle (mLDTA) and the associated duration of the correction (CP), fixation (FP) and frame-on periods (FoP) in patients who underwent correction to have the legs shape as requested and those who underwent tibial deformity correction. Material and methods There were 43 patients (84 segments operated on) in the cosmesis group and 15 participants (28 segments operated on) in orthopedic group. Preperative MAD, mMPTA, mLDTA measured 17.48 ± 1.14 mm medially, 84.90 ± 0.35° and 90.61 ± 0.39° in the cosmesis patients; 19.18 ± 2.86 mm medially, 84.04 ± 0.35°, 89.09 ± 0.37° in orthopaedic patients with no statistically significant differences observed between the groups. Results CP, FP and FoP lasted for 41.93 ± 3.96, 97.67 ± 7.78 and 139.60 ± 5.15 days in the cosmesis group, and 18.22 ± 3.05, 134.89 ± 9.42 and 153.00 ± 8.49 in controls. FP/CP, CP/FoP, FP/FoP measured 0.57 ≈ 1/2, 0.31 ≈ 1/3, 0.69 ≈ 2/3 in the cosmesis group and 0.15 ≈ 1/7; 0.12 ≈ 1/8; 0.88 ≈ 7/8 in controls. MAD, mMPTA, mLDTA measured 6.08 ± 0.87 mm laterally, 90.80 ± 0.31°, 88.62 ± 0.35° in the cosmesis participants, and 0.61 ± 0.82 mm laterally, 89.46 ± 0.54°, 87.68 ± 0. 63° in controls. Discussion There were no statistically significant differences in FoP with different duration of CP (≈ 1/3 FoP for the cosmesis group and ≈ 1/8 FoP for controls). The means of MAD, mMPTA of measured up to tibial valgus in cosmesis patients and were well within acceptable limits of normal in controls.Tibial valgus was caused by too much overcorrection (by ¼ on average).

Potential Influence of Factors For Genu Valgus With Hereditary Multiple Exostoses

Background: Genu valgus is one of the most common limb deformities in hereditary multiple exostoses (HME). However, it is easily concealed and may account for subsequent osteoarthritis of the knee. The potential influence of factors for genu valgus is still not well known. Methods: The knees of 56 patients (33 male, 23 female) with HME were investigated bilaterally. The mean age at evaluation was 8.9 years (range, 1.5–15.8 years). Knee valgus was described by the mechanical axis deviation (MAD), mechanical lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA). We investigated gender, age, body mass index (BMI), total number of palpable osteochondromas, number of radiographic osteochondromas around the knee, forearm deformities, morphology and distribution of lesions, and correlations between these factors and genu valgus. The measurement of LDFA and MPTA was to identify the sources of genu valgus deformity.Results: Based on the measurement of the mechanical axis, limbs were classified as genu valgus (n = 22) or normal mechanical axis groups (n = 90). The different severities of the genu valgus patients were classified by MAD. By bivariate logistic regression, genu valgus was significantly associated with more sessile and flared metaphyseal lesions. However only the number of flared metaphyseal lesions had a significant influence on the severity of genu valgus. By analyzing the LDFA and medial proximal tibial angle MPTA, it was found that abnormalities of both proximal tibia and distal femur play important roles in genu valgus. There were no differences between the genu valgus and normal mechanical axis groups in forearm deformities caused by HME, nor did this differ by severity of genu valgus. Conclusions: Early detection of sessile and flared metaphyseal knee lesions in patients with HME can contribute to early intervention of genu valgus.Level of Relevance: Level 2.

Varus alignment of the proximal tibia is associated with structural progression in early to moderate varus osteoarthritis of the knee

Purpose Lower limb malalignment is a strong predictor of progression in knee osteoarthritis. The purpose of this study is to identify the individual alignment variables that predict progression in early to moderate osteoarthritis of the knee. Method A longitudinal cohort study using data from the Osteoarthritis Initiative. In total, 955 individuals (1329 knees) with early to moderate osteoarthritis (Kellgren-Lawrence grade 1, 2 or 3) were identified. All subjects had full-limb radiographs analysed using the Osteotomy module within Medicad® Classic (Hectec GMBH) to give a series of individual alignment variables relevant to the coronal alignment of the lower limb. Logistic regression models, with generalised estimating equations were used to identify which of these individual alignment variables predict symptom worsening (WOMAC score > 9 points) and or structural progression (joint space narrowing progression in the medial compartment > 0.7mm) over 24 months. Results Individual alignment variable were associated with both valgus and varus alignment (mechanical Lateral Distal Femoral Angle, Medial Proximal Tibial Angle and mechanical Lateral Distal Tibial Angle). Only the Medial Proximal Tibial Angle was significantly associated with structural progression and none of the variables was associated with symptom progression. The odds of joint space narrowing progression in the medial compartment occurring at 24 months increased by 21% for every one degree decrease (more varus) in Medial Proximal Tibial Angle (p < 0.001) Conclusions Our results suggest that the risk of structural progression in the medial compartment is associated with greater varus alignment of the proximal tibia. Level of evidence Level III, retrospective cohort study.

Anatomic Versus Mechanically Aligned Total Knee Arthroplasty for Unicompartmental Knee Arthroplasty Revision

Objectives:The purpose of this study was to compare the intra-operative benefits and the clinical outcomes from kinematic or mechanical alignment for total knee arthroplasty (TKA) in patients undergoing revision of failed unicompartmental kneel arthroplasty (UKA) to TKA.Methods:Ten revisions were performed with a kinematic alignment technique and 11 with a mechanical alignment. Measurements of the hip-knee-ankle angle (HKA), the lateral distal femoral angle (LDFA), and the medial proximal tibial angle (MPTA) were performed using long-leg radiographs. The need for augments, stems, and constrained inserts was compared between groups. Clinical outcomes were compared using the WOMAC score along with maximum distance walked as well as knee range of motion obtained prior to discharge. All data was obtained by a retrospective review of patient files.Results:The kinematic group required less augments, stems, and constrained inserts than the mechanical group and thinner polyethylene bearings. There were significant differences in the lateral distal femoral angle (LDFA) and the medial proximal tibial angle (MPTA) between the two groups (p<0.05). The mean WOMAC score obtained at discharge was better in the kinematic group as was mean knee flexion. At last follow up of 34 months for the kinematic group and 58 months for the mechanical group, no orthopedic complications or reoperations were recorded.Conclusion:Although this study has a small patient cohort, our results suggest that kinematic alignment for TKA after UKA revision is an attractive method. Further studies are warranted.