Severe genu varus deformity does not affect enhanced recovery after surgery total knee arthroplasty outcomes.

INTRODUCTION: Enhanced recovery after surgery (ERAS) has been increasingly adopted in orthopaedic surgery. Although not an exclusion criterion, patients undergoing total knee arthroplasty (TKA) with preoperative severe varus deformity may be less likely to be enrolled for ERAS. This study aimed to compare the success of ERAS TKA between patients with severe preoperative varus deformities (≥ 15° varus) and the control group (< 15° varus to 14° valgus). Our secondary aim was to compare postoperative complications and functional outcomes between the two groups. MATERIALS & METHODS: 310 TKAs performed from August 2019 to February 2021 were analyzed with a follow-up of 6 months postoperatively. The primary outcome, ERAS TKA success, was defined as length of hospital stay of < 24 h. Other parameters included 30-day postoperative complications and clinical outcomes such as the original Oxford Knee Score (OKS), the Knee Society Knee (KSKS) and Function Score (KSFS), Visual Analog Scale for Pain (VAS-P), 36-Item Short-Form Health Survey (SF-36) Physical Component Summary (PCS) and SF-36 Mental Component Summary (MCS). RESULTS: There were 119 patients in the severe deformity group and 191 patients in the control group. There were no significant differences in ERAS success between the severe deformity group and control group, with both groups achieving similarly high rates (> 90%) of ERAS success. There were also no differences in 30-day postoperative complications and 6-month postoperative clinical outcomes. CONCLUSION: Patients with severe preoperative varus deformity undergoing ERAS TKA achieved high ERAS success rates (> 90%). Genu varum is not a contraindication for ERAS TKA.

Seven phenotypes of varus osteoarthritic knees can be identified in the coronal plane.

PURPOSE: Recommendations for resecting distal femur and proximal tibia in mechanical and anatomical alignment techniques are standardized. Kinematic alignment propagates individualizing resection planes. Whether significant variation exists, to warrant departure from standardized resection planes, has not been shown thus far in a large cohort of knees and with a wide range of varus deformity. The null hypothesis of this study was that there was no phenotypic variation in varus osteoarthritic knees. The aim of this paper was to determine whether distinct phenotypes could be identified, based on variations in coronal femoral and tibial morphology, which could aid in surgical planning and categorizing varus knees for future studies. METHODS: 2129 full-leg weightbearing radiographs were analyzed (1704 preoperative; 425 of contralateral arthritic knee). Measurements made were of HKA (hip-knee-ankle angle), VCA (valgus correction angle), mLDFA (lateral mechanical distal femoral angle), aLDFA (lateral anatomical distal femoral angle), MPTA (medial proximal tibial angle), MNSA (medial neck shaft angle), TAMA (angle between tibial mechanical and anatomical axes), and TPDR (percentage length of tibia proximal to extra-articular deformity). RESULTS: Seven distinct types were identified covering 2021 knees, reducible to 4 broad phenotypes: 11% were Type 1 'Neutral' knees showing values close to reported normal knees (mean VCA 5.5°, mLDFA 87°, aLDFA 81°). 38% were Type 2 'Intra-articular varus' with medial intra-articular bone loss (mean mLDFA 90.9°, MPTA 85.4°, VCA of 5.7°). 41% were Type 3 'Extra-articular varus' with extra-articular deformity (EAD). Type 3a had proximal tibial EAD; Type 3b had tibial diaphyseal EAD; Type 3c had femoral EAD (mean VCA 8.7°, HKA 166°), and severe medial bone loss (mean mLDFA 92°, MPTA 83°). 9% were Type 4 'Valgoid type' with features of valgus knees: Type 4a had medial femoral bowing (mean VCA 2.9°); Type 4b had significant distal femoral valgus (mean mLDFA 85.3°, aLDFA 78.6°). CONCLUSIONS: The null hypothesis that there was no phenotypic variation in varus osteoarthritic knees was rejected as considerable variation was found in coronal morphology of femur and tibia. Four broad phenotypic groups could be identified. Plane of the knee joint articular surface was quite variable. This has relevance to planning and performance of corrective osteotomies, unicompartmental and total knee arthroplasty. LEVEL OF EVIDENCE: III, retrospective cohort study.

Finite-element analysis of the proximal tibial sclerotic bone and different alignment in total knee arthroplasty.

BACKGROUND: Despite potential for improving patient outcomes, studies using three-dimensional measurements to quantify proximal tibial sclerotic bone and its effects on prosthesis stability after total knee arthroplasty (TKA) are lacking. Therefore, this study aimed to determine: (1) the distribution range of tibial sclerotic bone in patients with severe genu varum using three-dimensional measurements, (2) the effect of the proximal tibial sclerotic bone thickness on prosthesis stability according to finite-element modelling of TKA with kinematic alignment (KA), mechanical alignment (MA), and 3° valgus alignment, and (3) the effect of short extension stem augment utilization on prosthesis stability. METHODS: The sclerotic bone in the medial tibial plateau of 116 patients with severe genu varum was measured and classified according to its position and thickness. Based on these cases, finite-element models were established to simulate 3 different tibial cut alignments with 4 different thicknesses of the sclerotic bone to measure the stress distribution of the tibia and tibial prosthesis, the relative micromotion beneath the stem, and the influence of the short extension stem on stability. RESULTS: The distribution range of proximal tibial sclerotic bone was at the anteromedial tibial plateau. The models were divided into four types according to the thickness of the sclerotic bone: 15 mm, 10 mm, 5 mm, and 0 mm. The relative micromotion under maximum stress was smallest after MA with no sclerotic bone (3241 µm) and largest after KA with 15 mm sclerotic bone (4467 µm). Relative micromotion was largest with KA and smallest with MA in sclerotic models with the same thickness. Relative micromotion increased as thickness of the sclerotic bone increased with KA and MA (R = 0.937, P = 0.03 and R = 0.756, P = 0.07, respectively). Relative micromotion decreased with short extension stem augment in the KA model when there was proximal tibial sclerotic bone. CONCLUSIONS: The influence of proximal tibial sclerotic bone on prosthesis's stability is significant, especially with KA tibial cut. Tibial component's short extension stem augment can improve stability.

Total knee arthroplasty in patients with varus deformities greater than ten degrees: survival analysis at a mean ten year follow-up.

INTRODUCTION: Total knee arthoplasty (TKA) is a secure procedure with more than 90% survival at ten years. The purpose of this study was to report both clinical and radiological outcomes of TKA with a varus > 10°. The second objective was to identify risk factors for failure or bad clinical results. Our hypothesis was that results and survey are comparable to TKA with lesser deformities. METHODS: Eighty-two TKA (69 patients) between January 2004 and December 2008 with a varus > 10° were reviewed retrospectively. The endpoints were clinical (range of motion, IKS knee score, Oxford, and SF-12) and radiological (HKA post-operative and the existence of radiolucent lines or loosening at last follow-up). RESULTS: Sixty-three TKA (55 patients) were assessed with a mean follow-up of 10.9 years. The global IKS score significantly increased (p = 0.04). Seven TKA needed a revision: two for sepsis, four for aseptic loosening, and one for polyethylene wear, with an overall survival of 91.6% at ten years. For aseptic loosening, the survival rate was 94.7% at ten years. Risk factors for failure were age (p = 0.001), weight (p = 0.04), and a post-operative HKA lesser than 175° (p = 0.05) for aseptic loosening. DISCUSSION: The hypothesis was confirmed: the results showed a significant improvement of function and quality of life with a survival rate comparable to those found in the literature for greater varus but also inferior to 10°. Three risk factors have been identified suggesting increased surveillance in these cases. CONCLUSION: The results of this survey confirm the work hypothesis. Total knee arthroplasty in patients with important axial deformities is a confirmed, reliable, patient-friendly and predictable good outcome procedure.

Does the Preoperative Varus Deformity Influence the Survival of Postoperative Neutral-Aligned TKAs? An Analysis With a Minimum 5-Year Follow-Up.

BACKGROUND: Postoperative neutral alignment may be an important factor for longevity of total knee arthroplasty (TKA). In knees with severe varus deformity, greater soft tissue release and bone resection were required to achieve neutral alignment. We investigated the relationship between the severity of preoperative varus deformity and longevity of neutral-aligned TKAs. METHODS: Of the 723 knees in patients who underwent primary TKA for varus-type osteoarthritis between November 1998 and June 2009, 496 knees aligned neutrally (the postoperative mechanical hip-knee-ankle [HKA] axis angle ranged between -3° and 3°) and followed up for at least 5 years were included in the study. The mean follow-up period was 9.28 years. Patients were divided into 4 groups based on their preoperative HKAs: mild (0° < HKA ≤ 5°, n = 79), moderate (5° < HKA ≤ 10°, n = 204), severe (10° < HKA ≤ 15°, n = 149), and very severe (HKA > 15°, n = 64) groups. Failure was defined as need for revisional TKA for mechanical reason. Survival was analyzed by Kaplan-Meier method and log-rank test. RESULTS: The overall failure rate was 2.02% (10 of 496 prostheses). The cumulative survival rates of neutral-aligned TKAs at 10 years were 97.4% (95% confidence interval [CI], 93.9%-100%), 99.0% (95% CI, 97.6%-100%), 97.8% (95% CI, 95.4%-100%), and 96.9% (95% CI, 92.6%-100%) in mild, moderate, severe, and very severe varus groups, respectively. There were no significant differences between group survival rates (P = .395). CONCLUSION: The severity of preoperative varus deformity did not affect survival rates of neutral-aligned TKAs over 10 years.

Increased Patellar Fracture Rate in Total Knee Arthroplasty With Preoperative Varus Greater Than 15°: A Case-Control Study.

BACKGROUND: Management of severe varus deformity requires soft tissue balancing for implantation of low-constraint knee prosthesis. Patellar complications have been rarely studied in this specific group. Our hypothesis was that severe genu varum (>15°) would increase the rate of patellar complications. METHODS: Using a prospective cohort of 4216 prostheses performed at a single center beginning in 1987, we analyzed 280 prostheses having preoperative varus greater than 15°, compared to 673 total knee arthroplasties (TKAs) with a preoperative hip-knee-ankle angle of 180° ± 2°. Preoperative and postoperative clinical and radiological characteristics were compared between the 2 groups, with particular attention paid to patellar complications. RESULTS: Average follow-up was 40.2 months (24-239). The mean preoperative Knee Society Score (KSS) was statistically higher in the normal (hip-knee-ankle angle 180° ± 2) axis group (62.65 vs 37.47, P = .001). At the last follow-up, no significant difference was found between the 2 groups in terms of postoperative KSS (87.5 in the varus group vs 87.3 in the normal axis group, P = .87). The rate of satisfied patients was identical between the 2 groups (85.3% vs 88.8%, P = .49). However, at mid-term, there were more patellar fractures in the varus group (2.9% vs 0.9%, P = .005). A significantly lower patellar height in both the varus group and the group of patella fractures (P < .001) was also found. CONCLUSION: TKA in severe varus knees produces a KSS equivalent to TKA in knees with a mechanical axis of 0 ± 2. The risk of patellar fracture could initiate a decline in patella resurfacing in patients with major varus deformation, especially in case of a preoperative patella baja.

Radiologic Factors Affecting Ankle Pain Before and After Total Knee Arthroplasty for the Varus Osteoarthritic Knee.

The aim of the present study was to evaluate the radiologic factors related to ankle pain before and after total knee arthroplasty (TKA) among patients with a varus osteoarthritic knee. Fifty-five patients (65 ankles) with a varus osteoarthritic knee who had undergone TKA and were followed up for >24 months were enrolled. For clinical assessment, the visual analog scale for pain and the American Orthopaedic Foot and Ankle Society ankle-hindfoot scale were used. For radiologic assessment, the mechanical axis deviation angle, talar tilt, tibial anterior surface angle, distal medial clear space, medial tibiotalar joint space, frontal tibial ground angle, and hindfoot alignment view angle were measured. The patients with ankle pain before TKA (11 ankles) had a larger hindfoot alignment view angle (9.2° ± 2.6°) than that of patients without ankle pain before TKA (54 ankles; 5.5° ± 4.8°; p = .007). The patients with newly developed ankle pain or experienced an aggravation of existing pain after TKA (8 ankles) had a significantly larger degree of residual varus (5.1° ± 2.1°) than did the patients without ankle pain before and after TKA or those with ankle pain before surgery. However, the severity of the pain was not different during the follow-up period (52 ankles; 1.6° ± 2.5°; p = .001). The results of the present study showed that residual varus deformity was associated with ankle pain after TKA. Surgeons should perform evaluations of the ankles of patients who complain of pain before and after TKA and should give careful attention to the correction of alignment during TKA.

Changes in biomechanical risk factors for knee osteoarthritis and their association with 5-year clinically important improvement after limb realignment surgery.

OBJECTIVE: To evaluate 5-year outcomes after lower limb realignment and test the hypothesis that surgery-induced changes in selected biomechanical risk factors for medial knee osteoarthritis (OA) are associated with clinically important improvements. DESIGN: We prospectively evaluated patient-reported outcomes, full-limb standing radiographs and gait biomechanics before, 6 months (surgery-induced change) and 5 years after medial opening wedge high tibial osteotomy (HTO) in 170 patients (46.4 ± 8.9 years, 135 males) with knee OA and varus alignment. Logistic regression tested the associations of 6-month changes in mechanical axis angle and knee adduction moment with achieving an increase of ≥10 points in the Knee injury and Osteoarthritis Outcome Score (KOOS)4 at 5 years, with and without adjusting for covariates. Gait data were also compared to existing data from healthy controls. RESULTS: Mean 5-year changes (95% confidence interval (CI)) were: KOOS4: +14.2 (10.8, 17.6); mechanical axis angle: +8.21° (7.58, 8.83); knee adduction moment: -1.49 %BW*Ht (-1.35, -1.63). The postoperative knee adduction moments were typically lower than values for healthy controls. When divided into quartiles, although all strata improved significantly, patients with reductions in knee adduction moment of 1.14-1.74 %BW*Ht (neither largest nor smallest changes) had highest 5-year KOOS4 scores. The 6-month change in knee adduction moment (odds ratios (OR) = 0.38; 95% CI: 0.22, 0.67), preoperative KOOS4 (OR = 0.96; 95% CI: 0.94, 0.99) and preoperative medial tibiofemoral narrowing grade (OR = 0.62; 95% CI: 0.37, 1.00) were negatively associated with having a 5-year clinically important improvement (C-statistic = 0.70). CONCLUSIONS: Substantial improvements in biomechanical risk factors and patient-reported outcomes are observed 5 years after medial opening wedge HTO. The surgery-induced change in load distribution during walking is significantly associated with long-term clinically important improvement.

Knee internal contact force in a varus malaligned phenotype in knee osteoarthritis (KOA).

PURPOSE: Multiple phenotypes characterized by different disease mechanisms have been hypothesized to explain the large variability in the knee osteoarthritis (KOA) population. The purpose of this study was: to estimate and compare the medial and lateral knee compression forces (CF) during gait of three subgroups of KOA subjects characterized by different alignment and cartilage disruption patterns. METHODS: A secondary data analysis was conducted on a sample of 39 KOA subjects and 18 controls (C). The patients were classified in the different groups according to the following criteria: Varus medial disease (VMD) (12): varus alignment and predominant medial cartilage degeneration Varus generalized disease (VGD) (17): varus alignment and cartilage degeneration that extends to the lateral compartment. Neutral alignment (NA) (10): neutral alignment. The total, medial and lateral CF corrected for body weight were estimated using an inverse dynamics model (AnyBody Modeling System, AnyBody Technology) during stance. RESULTS: The impulse of the medial compressive force (MCF) (overall effect of the CF over the stance) was significantly higher (P < 0.01) in the VMD compared to all the other groups. Peak MCF was higher in the VMD compared to all the other groups, but the difference reached significance only when compared to the VGD group (P < 0.05). The results of the regression analysis showed a significant relationship in the VMD group between alignment and impulse of the MCF (R2 = 0.62; P < 0.01). This relationship disappears in the other groups. CONCLUSIONS: These findings suggest the existence of a phenotype characterized by increased MCF.

Early full weight-bearing versus 6-week partial weight-bearing after open wedge high tibial osteotomy leads to earlier improvement of the clinical results: a prospective, randomised evaluation.

PURPOSE: Open wedge high tibial osteotomy is a widespread treatment option in patients with varus malalignment and medial compartment osteoarthritis. There is no standardised protocol for post-operative rehabilitation available. The purpose of this study was to compare two post-operative rehabilitation protocols and to evaluate the clinical outcome of early full weight-bearing after open wedge HTO. METHODS: One hundred and twenty consecutive patients with varus malalignment and medial compartment osteoarthritis received an open wedge HTO using an angular locking plate fixation between December 2008 and December 2011. All patients were assigned randomly into one of two groups with different post-operative rehabilitation protocols (11-day vs. 6-week 20-kg partial weight-bearing). Clinical outcome was evaluated using established instruments (Lequesne, Lysholm, HSS and IKDC scores) preoperatively, 6, 12 and 18 months post-operatively. Deformity analysis was performed preoperatively and during follow-up. RESULTS: All clinical scores showed a significant pre- to post-operative improvement. After 6 months, there was a higher improvement in the group of early full weight-bearing. The difference between preoperative and 6-month follow-up for the group with early full weight-bearing and for the group with 20-kg PWB for 6 weeks was 28 ± 26 and 18 ± 22, respectively, for the Lysholm score and -5.0 ± 5.1 and -3.0 ± 3.6, respectively, for the Lequesne score. CONCLUSIONS: Early full weight-bearing (11-day 20-kg partial weight-bearing) after open wedge HTO without bone graft leads to earlier improvement of the clinical results and can be recommended for post-operative rehabilitation after open wedge HTO and fixation with an angular locking plate. LEVEL OF EVIDENCE: Therapeutic study, Level I.

Individual valgus correction angle improves accuracy of postoperative limb alignment restoration after total knee arthroplasty.

PURPOSE: The purpose of the current study was to compare and investigate the effect of fixed and individual valgus correction angle (VCA) on postoperative alignment restoration. It is hypothesized that individual VCA would be more accurate than fixed VCA in postoperative limb alignment restoration. METHODS: Four hundred and fifty-two patients with 546 consecutive uncomplicated primary total knee arthroplasties performed by a single surgeon, with 302 knees that had individual VCA (group A) and 244 knees that had fixed 5° VCA (group B), were enroled in this study. Preoperative and postoperative full-length standing hip-to-ankle radiographs were used to assess limb alignment. Postoperative hip-knee-ankle angle (θ), femoral component angle (α) and tibial component angle (ß) were measured and compared between the two groups. RESULTS: Mean postoperative θ angle and α angle were 178.9° (SD 1.3°) and 89.1° (SD 1.1°) in the group A, whereas they were 177.8° (SD 1.9°) and 87.9° (SD 1.5°) in the group B. There were significant differences in both parameters between the two groups (p = 0.021 and 0.016, respectively). Mean postoperative ß was 89.8° (SD 1.2°) in the group A and 89.7° (SD 1.3°) in the group B, and no significant difference was detected. There were 114 (37.7 %), 221 (73.2 %) and 265 (87.7 %) knees that had restoration of mechanical axis to ±1°, ±2°, ±3° of neutral, respectively, and 37 (12.3 %) outliers (>±3°) in the group A, whereas there were 48 (19.7 %), 122 (50.0 %) and 170 (69.7 %) knees that had restoration of mechanical axis to ±1°, ±2°, ±3° of neutral, respectively, and 74 (30.3 %) outliers in the group B. Group A had a higher percentage of restoration of limb alignment and fewer outliers than those in the group B, and this difference was statistically significant (p < 0.001). CONCLUSIONS: The results from the present study demonstrated that individual VCA for distal femoral resection could enhance the accuracy of postoperative limb alignment restoration compared with fixed VCA. For clinical relevance, individual VCA should be recommended for routine use in all patients in order to achieve the expected postoperative neutral limb alignment and reduce the risk of postoperative malalignment due to the planning error of a fixed VCA. LEVEL OF EVIDENCE: Prospective comparative study, Level II.

Changes in posterior tibial slope angle in patients undergoing open-wedge high tibial osteotomy for varus gonarthrosis.

PURPOSE: In this study, postoperative changes in the posterior tibial slope angle and clinical outcomes following open-wedge high tibial osteotomy were evaluated. METHODS: This study included 39 knees (18 left, 21 right) of 35 patients (three male, 32 female; median age, 53 years; age range 37-64 years) with symptomatic isolated medial joint osteoarthritis who underwent open-wedge high tibial osteotomy and fixation with a Puddu plate. The patients were clinically assessed according to the Lysholm knee score, a visual analogue pain scale, and a patient satisfaction questionnaire. Radiological assessment was made according to the changes in the posterior tibial slope angle and the correlation between these changes and clinical signs. The median follow-up period was 11 years (range 7-14 years). RESULTS: Significant improvements were observed in the preoperative and postoperative clinical scores of the Lysholm knee scale, visual analogue pain scale, and patient satisfaction questionnaire (p < 0.05). Radiological assessment showed that the posterior tibial slope angle was significantly higher during the postoperative and follow-up periods (p  0.05). There was no correlation between the postoperative Lysholm scores and the increase in the posterior tibial slope angle (p = n.s.). CONCLUSIONS: We conclude that both the conventional Puddu plate design and its anteromedial plate placement are what increase the tibial slope after an opening-wedge proximal tibial osteotomy. Therefore, current new plate design may help preserve the posterior tibial slope angle. LEVEL OF EVIDENCE: IV.

Growth Modulation in Achondroplasia.

INTRODUCTION: Achondroplasia is the most common skeletal dysplasia with a rate of nearly 1/10,000. The development of lower extremity deformity is well documented, and various modes of correction have been reported. There are no reports on the use of growth modulation to correct angular deformity in achondroplasia. METHODS: Medical Records from 1985 to 2015 were reviewed for the diagnosis of achondroplasia and growth modulation procedures. Patients who had been treated for angular deformity of the legs by growth modulation were identified. A detailed analysis of their medical record and preoperative and final lower extremity radiographs was completed. RESULTS: Four patients underwent growth modulation procedures, all to correct existing varus deformity of the legs. Three of the 4 patients underwent bilateral distal femoral and proximal tibial growth modulation. The remaining patient underwent tibial correction only. Two of the 4 patients had a combined proximal fibular epiphysiodesis. All limbs had some improvement of alignment; however, 1 patient went on to bilateral osteotomies. Only 1 limb corrected to a neutral axis with growth modulation alone at last follow-up, initial implantation was done before 5 years of age. CONCLUSIONS: Growth modulation is an effective means for deformity correction in the setting of achondroplasia. However implantation may need to be done earlier than would be typical for patients without achondroplasia. Osteotomy may still be required after growth modulation for incomplete correction.

Algorithmic pie-crusting of the medial collateral ligament guided by sensing technology affects the use of constrained inserts during total knee arthroplasty.

BACKGROUND: Intra-operative sensing technology is an alternative to standard techniques in total knee arthroplasty (TKA) for determining balance by providing quantitative analysis of loads and point of contact throughout a range of motion. We used intra-operative sensing (VERASENSE-OrthoSensor, Inc.) to examine pie-crusting release of the medial collateral ligament in knees with varus deformity (study group) in comparison to a control group where balance was obtained using a classic release technique and assessed using laminar spreaders, spacer blocks, manual stress, and a ruler. METHODS: The surgery was performed by a single surgeon utilizing measured resection and posterior-stabilized, cemented implants. Seventy-five study TKAs were matched 1:3 with 225 control TKAs. Outcome variables included the use of a constrained insert, functional- and knee-specific Knee Society score (KSS) at six weeks, four months, and one year post-operatively. Outcomes were analyzed in a multivariate model controlling for age, sex, BMI, and severity of deformity. RESULTS: The use of a constrained insert was significantly lower in the study group (5.3 vs. 13.8%; p = 0.049). The use of increased constraint was not significant between groups with increasing deformity. There was no difference in functional KSS and knee-specific KSS between groups at any follow-up interval. CONCLUSION: An algorithmic pie-crusting technique guided by intra-operative sensing is associated with decreased use of constrained inserts in TKA patients with a pre-operative varus deformity. This may cause a positive shift in value and cost savings.

Bilateral Early Knee Osteoarthritis Treated With Unilateral Proximal Tibial Osteotomy And Contralateral Non-Surgical Technique.

Some non-surgical techniques that decrease the mechanical load of the knee may be effective in treating early primary knee osteoarthritis. Thirtysix consecutive patients with bilateral early primary knee osteoarthritis and genu varum were treated with unilateral proximal tibial osteotomy in the more degenerated knee. After the osteotomized bone healed, ambulation with protected weight bearing using a cane in the contralateral hand was advised continuously for at least three months or until knee pain subsided bilaterally. Thirty-one patients were followed for an average of 4.6 years (range, 2.1-7.8 years). All osteotomized bones healed. Twenty patients (64.5%) had satisfactory knee function bilaterally. Eight patients (25.8%) only had satisfactory knee function in the operated knee. Thus, 28 patients (90.3%) improved operated knee function (p < 0.001). Non-operated knees improved to satisfactory function from 38.7% initially to 71.0% at the latest follow-up (p = 0.01). Bilateral early primary knee osteoarthritis may be successfully treated with unilateral proximal tibial osteotomy.

Is There A Difference In Outcome Between Two Types Of Valgus Unloading Braces? A Randomized Controlled Trial.

The short-term clinical and radiographic outcomes of two different valgus unloading braces were compared in patients with medial knee osteoarthritis (OA) and a varus leg alignment. A RCT was performed in 100 patients (50 Bledsoe Thruster brace, 50 SofTec OA brace) with symptomatic medial knee OA and a varus leg alignment. Outcomes were the visual analogue scale pain and satisfaction, Dutch Western Ontario and McMaster Universities Osteoarthritis Index, SF-12, 6-Minutes Walking Test, hip-knee-ankle alignment, analgesic use, complications and compliance after a follow-up of 2 and 12 weeks. The clinical and radiographic outcomes were not significant different between both groups. Almost all clinical outcomes improved in both groups at follow-up compared to baseline. 24% of the patients discontinued using the brace. No significant differences in clinical and radiographic outcomes were found between both groups after 2 and 12 weeks follow-up. Both braces were effective in the treatment of varus medial knee OA. Complications and compliance remains a problem.

Comparison of Postoperative Alignment Using Fixed vs Individual Valgus Correction Angle in Primary Total Knee Arthroplasty With Lateral Bowing Femur.

BACKGROUND: Lateral bowing of the femur, commonly observed among Asian populations, may cause malalignment after primary total knee arthroplasty (TKA). Therefore, in this study, a fixed valgus correction angle (VCA) technique for TKA was compared with individual VCA to determine which surgical technique leads to better limb and component alignment. METHODS: Patients with primary TKAs with lateral bowing femurs (n = 133) were randomized to 2 groups: individual VCA (group A) and fixed VCA (group B). Full-length standing hip-knee-ankle radiographs were used to measure the VCA and limb alignment. The postoperative mechanical axis, femoral component, and tibial component alignment were measured and compared between the 2 groups. RESULTS: The mean postoperative mechanical axis and femoral component alignment were 178.1° and 88.3°, respectively, in group A, compared with 175.9° and 86.4°, respectively, in group B (P < .05). There were 52 (77.6%) knees with ±3° mechanical axis deviation from the neutral axis in group A, compared with 19 (28.8%) in group B (P < .001). There were 56 (83.6%) knees with femoral component alignment deviation within ±3° in group A, compared with 26 (39.4%) in group B (P < .001). CONCLUSION: The individual VCA achieves a better radiographic limb and femoral component alignment than fixed VCA in our study patients. Preoperative hip-knee-ankle radiographs are imperative for distinguishing a bowing femur and performing accurate planning of the distal femoral resection.

A radiographic analysis of alignment of the lower extremities--initiation and progression of varus-type knee osteoarthritis.

OBJECTIVE: This study aimed to investigate alignment based on age in normal knees and alignment based on deformity in osteoarthritis (OA) knees using detailed radiographic parameters. DESIGN: Various parameters were measured from weight-bearing long leg radiographs of 1251 legs (797 normal and 454 OA knees) as a cross-sectional study. Normal knees were classified by age (young, middle aged, aged, and elderly) and symptomatic OA knees on the basis of the alignment (femorotibial angle (FTA): mild, moderate, severe and profound). The mean measurements in each group were calculated and compared within each group. RESULTS: The femoral shaft showed medially bowed curvature (femoral bowing) of approximately 2° in the young normal group, which shifted to lateral bowing with age. However, OA knees showed larger lateral bowing with OA grade, which might reduce the condylar-shaft angle and subsequently shifted the mechanical axis medially. Progression of mild to moderate OA might be associated with a decreasing condylar-shaft angle (femoral condylar orientation) and widening condylar-plateau angle (joint space narrowing) rather than decreasing tibial plateau flattering. Steeping of the tibial plateau inclination due to increasing tibial plateau shift (tibial plateau compression) rather than medial tibial bowing might be the main contributor to worsening of varus deformity in knees with severe and profound OA. CONCLUSIONS: This cross-sectional study might provide the possibility of OA initiation and progression. The lateral curvature of the femoral shaft associated with aging may contribute to the initiation of varus-type OA of the knee. These changes in the femur may be followed by secondary signs of OA progression including varus femoral condylar orientation, medial joint space narrowing, and tibial plateau compression.

Valgus bracing in symptomatic varus malalignment for testing the expectable "unloading effect" following valgus high tibial osteotomy.

PURPOSE: The purpose of this study was to evaluate whether the expectable postoperative pain relief following valgus high tibial osteotomy (HTO) is reliably predictable with the temporary use of an unloading knee brace preoperatively. METHODS: Fifty-seven patients with symptomatic varus malalignment were treated with a valgus producing unloading knee brace for 6-8 weeks. The pain intensity in the respective knee compartment was monitored using the visual analogue scale (VAS) before and following this treatment. A "positive" Brace-Test was defined as a pain relief medially without initiated symptoms laterally. In these cases, a valgus HTO was suggested as a promising surgical option. Patients who were subsequently operated were clinically re-evaluated 1 year postoperatively to compare the postoperative outcome with the result of the Brace-Test. RESULTS: The mean VAS score decreased from 6.7 [standard deviation (SD) 1.6] to 2.5 points (SD 1.7) (p < 0.001) following the Brace-Test. Overall, 48 patients had a positive test. A valgus HTO was performed in 29 of them. The mean postoperative VAS score was 1.9 (SD 1.7) points with no difference to the result of the test (n.s.). Nineteen patients with a positive test initially decided for a conservative treatment. In three of nine patients with a negative test, a total knee replacement was performed. CONCLUSION: This study shows that the temporary use of an unloading valgus producing knee brace may well predict future outcome of HTO surgery in terms of expectable postoperative pain relief. The Brace-Test gives both the patient and the orthopaedic surgeon more detailed preoperative information, especially in critical or borderline indications. Thus, it is a useful tool to test the unloading effect before indicating an HTO. LEVEL OF EVIDENCE: III.

Varus thrust and knee frontal plane dynamic motion in persons with knee osteoarthritis.

OBJECTIVE: Varus thrust visualized during walking is associated with a greater medial knee load and an increased risk of medial knee osteoarthritis (OA) progression. Little is known about how varus thrust presence determined by visual observation relates to quantitative gait kinematic data. We hypothesized that varus thrust presence is associated with greater knee frontal plane dynamic movement during the stance phase of gait. METHODS: Participants had knee OA in at least one knee. Trained examiners assessed participants for varus thrust presence during ambulation. Frontal plane knee motion during ambulation was captured using external passive reflective markers and an 8-camera motion analysis system. To examine the cross-sectional relationship between varus thrust and frontal plane knee motion, we used multivariable regression models with the quantitative motion measures as dependent variables and varus thrust (present/absent) as predictor; models were adjusted for age, gender, body mass index (BMI), gait speed, and knee static alignment. RESULTS: 236 persons [mean BMI: 28.5 kg/m(2) (standard deviation (SD) 5.5), mean age: 64.9 years (SD 10.4), 75.8% women] contributing 440 knees comprised the study sample. 82 knees (18.6%) had definite varus thrust. Knees with varus thrust had greater peak varus angle and greater peak varus angular velocity during stance than knees without varus thrust (mean differences 0.90° and 6.65°/s, respectively). These patterns remained significant after adjusting for age, gender, BMI, gait speed, and knee static alignment. CONCLUSION: Visualized varus thrust during walking was associated with a greater peak knee varus angular velocity and a greater peak knee varus angle during stance phase of gait.