Varus Deformity Of Knee Research Articles

A cruciate-retaining implant can treat both knees of most windswept deformities when performed with calipered kinematically aligned TKA.

Surgeons performing total knee arthroplasty (TKA) on the osteoarthritic valgus deformity often use a posterior stabilized (PS) and semi-constrained implants to substitute for the release of a contracted posterior cruciate ligament (PCL) instead of a cruciate retaining (CR) implant. Calipered kinematic alignment (KA) strives to retain the PCL and use a CR implant. The aim of this study of the windswept deformity was to determine whether the level of implant constraint, outcome scores, and alignment after bilateral calipered KA TKA are different between a pair of knees with a varus and valgus deformity in the same patient. A review of aprospectively collected database identifiedall patients with a windswept deformity treated with bilateral TKA (n = 19) out of2430 consecutive primary TKAsperformed between 2014 and 2019.Operative reports determined the level of implant constraint. Patient response to the Forgotten Joint Score (FJS) and Oxford Knee Score (OKS) assessed outcomes at a mean follow-up of 2.3years. Postoperative alignment was measured on an A-P computer tomographic scanogram of the limb. CR implants were used in 15 of 19 (79%) valgus deformities and 17 of 19 (89%) of varus deformities (n.s.). No knees required a semi-constrained implant. There was no difference in the median postoperative FJS and OKS (n.s.), and a 1° or less difference in the mean postoperative distal lateral femoral angle (p = 0.005) and proximal medial tibial angle (n.s.) between the paired varus and valgus knee deformity. Based on this small series, surgeons that use calipered KA TKA can expect to use CR implants in most patients with windswept deformity and achieve comparable outcome scores and alignment between the paired varus and valgus deformity. IV.

Effect of Lower-Extremity Angular Imbalance on Foot and Ankle Pain in Patients With Genu Varus Deformity

When there is a varus knee deformity, the ankle and foot compensate. However, the association between pain and angular change in the compensatory mechanism is not well understood. Therefore, we investigated the relationship between pain and angular change of the lower extremity in genu varus patients. Standing whole-lower-leg plain radiographs of 127 legs (77 patients) with >4° of genu varum were evaluated. Pain was assessed separately at the ankle, forefoot, and hindfoot. Knee, ankle, and subtalar joint angles were measured. Patients were divided into 3 groups according to the degree of lower leg angular imbalance (group 1, mild; group 2, moderate; group 3, severe). The presence of multiple pain locations differed significantly between groups and was significantly higher in group 3 than group 1 (p = .0061). Likewise, the subtalar angle was significantly more varus in group 3 than group 1 (p = .012). In conclusion, an unbalanced lower extremity with genu varum was associated with multiple foot and ankle pain, and the subtalar joint played a primary role in compensation for genu varum deformity.

Combined posterior cruciate ligament and chronic posterolateral corner deficiency in varus knee, two-stage reconstruction

Background Conservative management of chronic posterolateral corner (PLC) knee injuries had a bad repetition and often followed by poor outcomes. In patients who had associated posterior cruciate ligament [PCL] and chronic PLC knee injuries with varus knee deformity, failure to correct the mechanical axis by correcting varus was usually followed by failure of the posterolateral knee repair or reconstruction. Aim of the study To assess prospectively the results of treatment of associated PCL and chronic PLC injury in the varus knee, with a two-stage procedure. Initial high tibial medial opening wedge osteotomy was followed by PCL reconstruction. Methods This study included 10 patients who had associated PCL and chronic PLC deficiency in varus knee who were treated by two-stage surgical technique, first stage was high tibial medial opening wedge osteotomy to align the mechanical axis and correct varus deformity, then PCL ligament reconstruction in the second stage. Results According to the International Knee Documentation Committee, the 10 patients included in the study [100%] were graded as grade C (abnormal) or D (sever abnormal) preoperatively, while 8 of the 10 patients [80%] were graded as grade A (normal) or B (nearly normal), and 2 patients [20%] were rated as abnormal grade C at final follow-up scoring. Statistically significant improvement was achieved. Radiologically, the average mechanical axis that preoperatively passed within the medial tibial plateau with varus deformity ranged between 10 and 15° in our cases, while the mechanical axis postoperatively passed through the mid of tibial plateau or slightly within the lateral tibial plateau with full correction of the deformity with valgus angle ranged from 5 to 10°. The preoperative posterior tibial sagittal slope angle was average 7.8°, which became 10.5° in the last follow-up visit. Conclusion Two-stage reconstruction of the knee in cases who had PLC injuries associated with varus knee, starting by proximal tibial medial opening wedge osteotomy followed by reconstruction of PCL, is a valuable technique and had good results.

Correction of excessive intraarticular varus deformities in total knee arthroplasty is associated with deteriorated postoperative ankle function.

The aim of this study was to demonstrate, whether the degree of limb alignment correction in varus knee osteoarthritis correlated with an increase in ankle symptoms and to define a cut-off value concerning the degree of correction above which to expect ankle problems. Ninety-nine consecutive patients with preoperative intraarticular varus knee deformities who underwent total knee arthroplasty were retrospectively analyzed. Patients were examined clinically (Knee Society Score, Forgotten Joint Score, Foot Function Index, Range of Motion of the knee and ankle joint, pain scales) as well as radiologically. The mean follow-up time was 57months. The degree of operative limb alignment correction strongly correlated with the Foot Function Index (R = 0.91, p < 0.05). Given this, higher degrees of knee malalignment corrections were associated with worse postoperative outcomes in the knee and ankle joint-despite postoperative improved joint line orientations. Subsequently, a cut-off value for arthritic varus deformities (14.5°) could be calculated, above which the prevalence of ankle symptoms increased manifold [OR = 15.6 (3.2-77.2 95% CI p < 0.05)]. Furthermore, ROM restrictions in the subtalar joint were associated with a worse outcome in the ankle joint. When correcting excessive intraarticular varus knee osteoarthritis, surgeons have to be aware of possible postoperative ankle symptoms and should consider ankle deformities or decreased subtalar ROM before operative procedures. III.

Comparison of Gap Balancing vs Measured Resection Technique in Patients Undergoing Simultaneous Bilateral Total Knee Arthroplasty: One Technique per Knee

BackgroundTotal knee arthroplasty requires careful surgical technique to attain the goal of a well-aligned and symmetrically balanced knee. Soft tissue balance and correct femoral component rotation are paramount in achieving these goals. The two competing techniques to select femoral component rotation and soft tissue balance are the gap balance technique and the measured resection technique. MethodsWe performed a randomized, prospective study to compare the two techniques in patients undergoing simultaneous bilateral total knee arthroplasty, whereby one technique was performed in each knee. Fifty (50) subjects were enrolled into the study. The inclusion criteria were osteoarthritic varus knee deformities with similar deformities in both knees. Subjects were followed up for a minimum of two years. ResultsThe knees balanced via the gap balance technique had significantly more posterior medial bone removed from the femur than those knees balanced via the measured resection technique (P < .001). Knees in the gap balance group tended to require more medial knee releases in extension and tended to have smaller sized femoral components as a result of cutting more bone from the femur in flexion. The modular tibial polyethylene bearing tended to be thicker in the gap balance group. Despite these differences, average knee flexion and functional revised Oxford Knee Scores at 2-year follow-up were not statistically different. ConclusionAt 2-year follow-up, there were no differences between the function and scores using the two techniques. Long-term follow-up will be necessary to evaluate any differences in long-term durability.

Short-term effectiveness of unicompartmental knee arthroplasty for knee osteoarthritis in super-age patients

To investigate the short-term effectiveness of unicompartmental knee arthroplasty (UKA) in the treatment of knee osteoarthritis of super-age patients over 85 years old. Senile patients with unilateral compartment osteoarthritis of the knee who received UKA between November 2013 and May 2017 and met the inclusion criteria were enrolled as the research objects. Among them, 40 patients (50 knees) were more than 85 years old (super-age group) and 44 patients (50 knees) were 52-81 years old (control group). There was significant difference in age between the two groups ( t=17.33, P=0.00). There was no significant difference in body mass index, degenerative classification of medial and lateral compartments, varus deformity of knee, disease duration, complicating diseases, and preoperative hemoglobin, hematocrit (HCT), American Hospital for Special Surgery (HSS) score, range of motion (ROM) of knee, visual analogue scale (VAS) score, and femoral-tibial angle (FTA) between the two groups ( P>0.05). Hospital stay, hemoglobin, and HCT of the two groups were recorded before operation and on the first day after operation. The changes of hemoglobin and HCT after operation were calculated. During follow-up period, the ROM of the knee, HSS score, and VAS score were measured; the position of the prosthesis and FTA were observed by X-ray films. There was no significant difference in hospital stay between the two groups ( t=1.05, P=0.29). Hemoglobin and HCT of the two groups on the first day after operation were significantly lower than those before operation ( P<0.05). There was no significant difference in the postoperative changes of hemoglobin and HCT between the two groups ( P>0.05). All the patients were followed up completely except 4 cases (5 knees) in the super-age group. The follow-up time ranged from 14 to 44 months of super-age group (mean, 29 months) and 21 to 33 months of control group (mean, 24 months). There were significant differences in HSS score, VAS score, ROM of the knee, and FTA between pre-operation and last follow-up in the two groups ( P<0.05). There was significant difference in HSS score between the two groups ( P<0.05), and no significant difference was found in ROM, VAS score, and FTA between the two groups ( P>0.05). X-ray film showed no adverse position of the prosthesis, infection around the prosthesis, prosthesis loosening, or pathological bright lines. UKA combined with reasonable perioperative management in the treatment of super-age patients over 85 years with knee osteoarthritis is safe and feasible, and can obtain satisfactory short-term effectiveness.

Correction osteotomy for bilateral varus knee deformity caused by premature epiphyseal closure induced by hypervitaminosis A: a case report

BackgroundA vitamin A derivative, 13-cis-retinoic acid (isotretinoin), has been administered to treat several types of pediatric cancer and has improved survival rates in patients despite being known to induce premature epiphyseal closure. As the number of patients treated by 13-cis-retinoic acid increases, demands for salvage treatment after systemic retinoid therapy are emerging. However, few studies have described the surgical treatment of this disease.Case presentationWe report a case with bilateral varus knee deformity due to premature epiphyseal closure that occurred during treatment with isotretinoin for neuroblastoma. The patient was successfully treated with correction osteotomy using a Taylor spatial frame in the right knee joint and femoral closed wedge osteotomy using a locking plate in left knee joint. Histopathological examination of the growth plate showed polar irregularity of chondrocytes and decreased cartilage matrix without apoptosis. In contrast, arthroscopic findings showed an intact joint surface. No recurrence of varus deformity was evident on follow-up at 1 year.ConclusionsTo the best of our knowledge, this represents the first report of correction osteotomy for varus knee deformity due to premature epiphyseal closure that occurred during treatment with isotretinoin.

High Tibial Opening Wedge Osteotomy in Osteoarthritis with Varus Knee

Background: High tibial osteotomy was first described in 1958 as a successful treatment for moderate to severe unicompartmental, degenerative arthritis of the knee associated with angular deformity. Malalignment is frequently associated with knee arthrosis and can influence the mechanical load through either the medial or the lateral compartment. Aim of the work: Investigation of the clinical and radiographic results of opening-wedge high tibial osteotomy and fixated by locked compression plate, when used to as surgical treatment of osteoarthritis and varus deformity. Patients and methods: The study took place at Al Azhar University Hospital {Elhussein and Bab EL Sharia}. It was a prospective study on 20 consecutive patients who had knee osteoarthritis and varus knee deformity. They were treated by surgical intervention by opening wedge high tibial osteotomy applied by T – locked plate, between September 2016 to April 2019. The procedures are carried out under spinal anesthesia. Results: There was a significant improvement in the pain level after surgery when compared to before surgery. Postoperatively, 16 patients (80%) were found to have no pain. Pre-operatively 19 patients (95%) had full range of knee motion, and only one patient had hyperextension. Post-operatively, all patients had maintained their full knee extension. Postoperatively, 60% of the patients showed normal alignment, 10% valgus (mean: 1° valgus) and 30% still varus (mean: 2.33° varus, range: 1-4°). Conclusion: The patients in this study were satisfied with the results. Younger patients planning for HTO should be advised about the benefits and risks of the procedure, specifically mentioning kneeling and scar formation.

Preoperative Varus-Valgus Stress Angle Difference Is Valuable for Predicting the Extent of Medial Release in Varus Deformity during Total Knee Arthroplasty.

PurposeThe purpose of this study was to compare the predictive value of the valgus stress angle (SA), varus SA and varus-valgus SA difference (VVD) in predicting the degree of medial release in varus deformity during total knee arthroplasty (TKA).Materials and MethodsOne hundred eight TKAs (78 patients), which were performed in primary osteoarthritis with varus knee deformity, were retrospectively classified into three groups according to the degree of medial release (group A, mild release; group B, moderate release; and group C, severe release). Medical charts were reviewed, and long weight bearing standing anteroposterior radiographs and varus-valgus stress radiographs were evaluated.ResultsThe valgus SA was significantly different between group A and B and between group A and C. However, it was not significantly different between group B and C. The varus SA was significantly different between group B and C and between group A and C. However, it was not significantly different between group A and B. The VVD was significantly different in all intergroup comparisons.ConclusionsEvaluation of the VVD is more valuable in predicting the degree of medial release in TKA performed in varus knee deformity than evaluation of the simple valgus and varus SA.

Compensatory Function of the Subtalar Joint for Lower Extremity Malalignment.

It is important to evaluate the subtalar joint and hip-knee-ankle alignment to understand lower extremity alignment. In this review, we focused on the compensatory changes in the subtalar joint alignment for the deformity of the knee and ankle joint, reviewing previous research. The subtalar joint alignment was compensatory valgus in patients with varus knee and ankle deformity, whereas it was uncertain whether the subtalar joint alignment was compensatory varus in patients with valgus knee and ankle deformity. The subtalar joint valgus alignment improved after total knee arthroplasty or high tibial osteotomy for varus knee deformity, even if the deformity was severe. In contrast, whether the subtalar joint alignment changed after the surgery for ankle or valgus knee deformity has not been considered. Further research on the compensatory function of the subtalar joint is needed.

Imaging study on effect of femoral intramedullary guide on the alignment of femoral prosthesis in unicompartmental knee arthroplasty

To explore the imaging features of intramedullary guide rod and its influence on the alignment of the femoral prosthesis in unicompartmental knee arthroplasty (UKA). Between August 2016 and November 2016, 50 patients (50 knees) with primary anteromedial osteoarthritis were treated with UKA by Oxford MicroPlasty minimally invasive replacement system. There were 10 males and 40 females. The age ranged from 62 to 77 years with an average of 68.8 years. Preoperative varus and flexion deformity angles were (5.22±3.46)° and (7.42±2.65)°, respectively. The knee range of motion (ROM) was (106.85±7.62)°. The Hospital for Special Surgery (HSS) score was 68.26±4.65. The angles between the femoral intramedullary guide rod and the anatomical axis of femur on the coronal and sagittal planes, the femoral component valgus/varus angle (FCVA), the femoral component posterior slope angle (FCPSA), knee varus deformity angle, and knee flexion deformity angle were measured by intra- and post-operative X-ray films. The postoperative ROM and HSS score were measured. Intraoperative X-ray films measurement showed that the lateral side angles between femoral intramedullary guide rod and femoral anatomical axis were observed on coronal plane, and the angles ranged from 0.28 to 2.06° with an average of 0.96°. While the posterior side angles were observed on sagittal plane, and the angles ranged from 0.09 to 0.48° with an average of 0.23°. The angulations (>1°) between femoral intramedullary part guide rod and outside part of the rod were confirmed in 12 cases (24%) on coronal plane. Postoperative femoral prosthesis were mild varus in 38 patients (76%). The FCVA ranged from -1.76 to 4.08° with an average of 2.21°. The FCPSA ranged from 7.12 to 13.86° with an average of 9.16°. All patients were followed up 22-26 months, with an average of 24.5 months. The incisions healed by first intention. At last follow-up, the varus and flexion deformity angles were (1.82±1.05) and (2.54 ± 1.86)°, respectively. ROM was (124.62±5.85)° and HSS score was 91.58±3.65. There were significant differences between pre- and post-operative parameters ( P<0.05). No complication such as dislocation or aseptic loosening of the prosthesis occurred during the follow-up. UKA by Oxford MicroPlasty minimally invasive replacement system can obtain accurate femoral prosthesis position with the help of intramedullary guide system, and the effectiveness is excellent.

Acute Correction of Varus Knee by Biplanar Medial Opening-Wedge High Tibial Osteotomy and Fixation with TomoFix Plate

Background: Biplanar medial opening wedge high tibial osteotomy (MOWHTO) is a treatment method that allows adequate correction of symptomatic varus knee deformity. However, MOWHTO tends to decrease patellar height and increase the posterior tibial slope, which can affect the knee joint stability. Objective: The aim of this study was to describe the technique of biplanar MOWHTO and fixation by TomoFix plate, as well as to evaluate the accuracy of the planned correction and the postoperative tibial slope. Patients and Methods: This prospective cohort study was conducted on patients who presented with varus knee deformity and underwent biplanar MOWHTO and fixation by TomoFix plate during the period from March 2016 to March 2017. Assessment of patients included pre- and postoperative Knee and function scores, mechanical femorotibial angle (mFTA), posterior tibial slope angle (pTSA), range of motion (ROM) and radiological evaluation of the healing of the osteotomy site. Results: The recruited patients were 13 (8 men and 5 women), with average age 31.7 years old. The knee and functional scores improved from the preoperative mean of 45 and 41 to the postoperative mean of 85 and 72 points, respectively. The average knee flexion was 115 degrees, which at the final follow-up remained unchanged except for one case. The mean preoperative mFTA was 13.5° varus and decreased post-operatively to a mean of 3° valgus. The average postoperative follow-up period was 12 months (10 - 18 M). Conclusion: The biplanar MOWHTO allows preservation of posterior tibial slope while correcting the varus knee adequately.

Bone autografting in medial open wedge high tibial osteotomy results in improved osseous gap healing on computed tomography, but no functional advantage: a prospective, randomised, controlled trial.

Medial open wedge high tibial osteotomy (owHTO) is a valuable surgical technique used to manage medial degeneration in varus knees. Iliac crest autograft is considered the gold standard gap-filler. It was hypothesised that iliac crest autograft promotes gap healing and improves functional outcome in owHTO. Between 2005 and 2009, patients scheduled to undergo owHTO stabilised by a medial locking compression plate were randomised to undergo owHTO either with iliac crest autograft (group A) or without bone void filler (group B). Pre- and postoperative leg axes were recorded. At 3 and 12months postoperatively, the healing of the osteotomy gap was measured as a percentage on CT images, and functional scores were recorded. There were 15 patients in group A, and 25 in group B. The groups were similar in age, sex ratio, knee varus deformity, body mass index, and smoking status. Group A and B had similar preoperative varus (6.9° vs. 7.6°) and postoperative valgus (2.2° vs. 3.0°). Compared with the control group, group A had a significantly greater degree of osseous gap healing after 3months (40.1% vs. 10.8%, p = 0.045) and 12months (91.5% vs. 59.1%, p ≤ 0.001). Multiple linear regression analysis found that bone grafting was an independent promoting factor for gap healing, while increased preoperative varus was an independent retardant factor at 3months (p = 0.004 and p = 0.002, respectively) and 12months (p ≤ 0.001 and p = 0.003, respectively). Younger age was a promoting factor for gap healing on CT at 3months (p ≤ 0.001), but not at 12months. No correlations were found between bone healing and functional outcome, body mass index, or smoking status. Iliac crest autograft significantly increases healing of the osteotomy gap after owHTO. Increased preoperative varus and older patient age are independent factors that delay early healing of the osteotomy. However, no functional advantage was found at 3 or 12months postoperatively. Therefore, routine use of iliac crest autograft cannot be recommended. II.

Using Tibia Proximal Cut Autograft in Advanced Varus Knee Deformity in Total Knee Arthroplasty; Outcomes Compared to the Control Group.

Background:The purpose of this study was to compare the outcomes of Total Knee Arthroplasty (TKA) performed for advanced varus knee deformity, which is performed by using tibia proximal cut bone for the reconstruction of the tibia proximal medial bone defects, with a control group consisting of TKAs which did not need reconstruction.Methods:Patients in the present study underwent total knee arthroplasty between 2009 and 2015. 12 patients with advanced varus deformity who had undergone reconstruction with tibia proximal cut autograft and 15 patients who were randomly selected from patients who did not need reconstruction, were compared clinically and radiographically.Results:The mean follow-up period of the patients was found to be 73.1 ± 19.7 (36-108) months in the reconstruction group and 73.2 ± 12.3 (39-107) months in the control group. (p> 0.05) In both groups, significant improvement was observed postoperatively. In both groups, there was no evidence of loosening the required revision. WOMAC score was 32.4 ± 13.3 (8-64) in the reconstruction group and 28.9 ± 17.2 (6-70) in the control group at the last control visit. There was no difference between the groups when comparing the WOMAC scores at the last control visit. In the reconstruction group, the Hip-Knee-Ankle (HKA) angle was 26.1 ± 4.9 ° varus preoperatively and 1.3 ± 2.3 ° valgus postoperatively; and in the control group 10.1 ± 2.1 ° varus preoperatively and 2.7 ± 3.4 ° valgus postoperatively. (p> 0.05)Conclusion:In the present study, clinical and radiographic results of total knee arthroplasty patients, who suffered from advanced knee varus deformity and whose proximal tibia medial defects were reconstructed by using tibial proximal cut autograft, have been found to be successful when compared to the control group.

Total knee arthroplasty in the varus knee: tips and tricks.

Varus knee deformity is very common, and it can be classified according to the severity and reducibility of the deformity. Pre-operative planning is mandatory to obtain a good result. Both clinical and radiological planning should be carefully performed, particularly focused on collateral ligament deficiency. In most of the cases, a postero-stabilized implant is necessary, but in the presence of a varus thrust, a midlevel constrained (MLC) implant may be necessary. Rarely, if a severe extra-articular deformity is present, a femoral osteotomy and a high constrain implant may be necessary. In most of the cases, a standard midline approach can be performed. Soft tissue balancing is crucial, avoiding excessive releases of the medial collateral ligament (MCL). In the presence of severe deformity, more aggressive procedure such as tibial reduction osteotomy or sliding medial epicondyle osteotomy can be performed. In literature, good outcomes are reported for total knee arthroplasty (TKA) in varus deformity. In this manuscript, the available literature on TKA in varus deformity is analyzed, and the preferred surgical techniques of the authors are described.

Clinical and radiologic results after open-wedge high tibial osteotomy in haemophilic knee arthropathy with varus deformity.

The previous studies have described only closed-wedge high tibial osteotomy (HTO) in haemophilic arthropathy (HA). The purpose of this study was to evaluate clinical and radiographic results after open-wedge HTO in HA with varus knee deformity. We included 13 open-wedge HTOs in HA performed between 2005 and 2016. The mean age of patients was 28.9years. Visual analogue scale (VAS), Western Ontario and McMaster Universities (WOMAC), and range of motion (ROM) indices were assessed. Any complications or requirements for total knee arthroplasty (TKA) were investigated. Mechanical axis (MA), minimal joint space width (mJSW) and Pettersson score were measured. Bone union rates at 3 and 6months postoperative were evaluated. VAS improved from 5.1 to 2.4 (P<.001). WOMAC was 66.5 preoperatively, and 26.6 postoperatively (P<.001). Pre- and postoperative ROM did not differ significantly. There were no cases of HTO converted to TKA, but one case of HTO required TKA 152months postoperative. No complications were observed. The MA was corrected from varus 5.1° to valgus 1.2° (P<.001). Pre- and postoperative mJSW did not significantly differ. Pettersson score improved from 3.84 to 2.47 (P<.001). The bone union rates at the osteotomy gap were 45.2% and 67.8% at 3 and 6months postoperative. Open-wedge HTO should be considered in cases of HA with varus deformity in young haemophilic patients, even though inflammatory arthritis is not an optimal indication for this procedure. It can be an appropriate treatment with respect to the choice to postpone TKA.

Relationship between Lateral Femoral Bowing and Varus Knee Deformity Based on Two-Dimensional Assessment of Side-to-Side Differences.

PurposeThe objective was to evaluate the relationship between side-to-side differences of lateral femoral bowing and varus knee deformity based on two-dimensional (2D) assessment in unilateral total knee arthroplasty (TKA).Materials and MethodsA total of 143 patients with varus knee osteoarthritis who underwent unilateral TKA were enrolled. We evaluated the side-to-side differences of the frontal lower limb alignment by assessing lateral femoral bowing, anatomical medial distal femoral angle, and anatomical medial proximal tibial angle (aMPTA).ResultsThe average values of all anatomical indices were significantly different between the operated side and the non-operated side (p<0.05). The side-to-side difference in hip knee ankle (HKA) angle had a statistically significant correlation with that in lateral femoral bowing (intraclass correlation coefficient, 0.259; p=0.002) and that in aMPTA. Linear regression analysis showed 0.199° of side-to-side difference in lateral femoral bowing was associated with 1° of side-to-side difference in bilateral HKA angle.ConclusionsThe side-to-side difference in lateral femoral bowing showed a tendency to increase in proportion to varus knee deformity based on 2D assessment in unilateral TKA patients.

Subtubercle Osteotomy for Medial Compartment Osteoarthritis of the Knee Using Ilizarov Technique: Survival Analysis and Clinical Outcomes.

High tibial osteotomy with acute correction and internal fixation can be used to correct malalignment and malorientation and reduce symptoms in patients with medial compartment osteoarthritis of the knee. To address the inadequacies of this technique, we performed a series of subtubercle tibial osteotomy (STO) procedures using circular ring fixation to correct knee varus malalignment and joint malorientation. The purpose of this study was to analyze the ability of this technique to delay subsequent knee arthroplasty and decrease symptoms. Sixty-one patients had a total of 72 STO procedures using the Ilizarov technique to correct a varus deformity of the proximal part of the tibia. Radiographic measurements were performed at the time of presentation and after osseous union and frame removal. Clinical and radiographic variables were compared from presentation to the time of the latest follow-up. We performed a survival analysis, and our primary outcome was the time to conversion to knee arthroplasty. Radiographic measurements, including mechanical axis deviation, medial proximal tibial angle, and joint line congruence angle, significantly improved after deformity correction (p < 0.001 for all). In patients with a preoperative flexion contracture, the proximal posterior tibial angle significantly increased toward normal values (mean, 77.8° pretreatment versus 82.4° posttreatment; p = 0.007). Survival analysis demonstrated a rate of native knee-joint survival without conversion to arthroplasty of 94.2% (95% confidence interval [CI], 83% to 98%) at 5 years, 84.0% (95% CI, 69% to 92%) at 10 years, and 51.3% (95% CI, 28% to 71%) at 15 years. In addition, time-trade-off and Brief Pain Inventory outcomes significantly improved (p < 0.001). The complication rate was 8%. STO procedures using the Ilizarov technique for symptomatic varus knee deformity, performed over the course of 18 years, resulted in high knee survival rates without arthroplasty and significant improvement in clinical status. The STO technique provides several advantages over acute correction with internal fixation through a conventional high tibial osteotomy, including maintenance of the patellofemoral relationship, no retained implants, and accurate coronal and sagittal plane corrections. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Preoperative knee deformity and kinematics impact postoperative knee kinematics in total knee arthroplasty

BackgroundThe purpose of this study was to evaluate the relationship between the preoperative knee deformity/kinematic pattern and the postoperative knee kinematic pattern in posterior cruciate ligament substituting (PS)-total knee arthroplasty (TKA). MethodsThis study involved 39 patients with medial osteoarthritis who underwent a primary PS-TKA using a computed-tomography-based navigation system. All the operations were performed by a single surgeon using a subvastus approach, modified gap technique and the same PS type of prosthesis (Genesis II™ total knee system, Smith & Nephew, Memphis, TN, USA). Knee deformity, kinematic pattern after capsule incision (preoperative knee kinematics), and kinematic pattern after implantation (postoperative knee kinematics) in PS-TKA were measured. Kinematic patterns were divided into two groups: a medial pivot group and a non-medial pivot group. ResultsPreoperative varus knee deformity was significantly larger in the non-medial pivot group than in the medial pivot group (femorotibial angle: 184.7±6.4° vs. 180.8±3.9°, P<0.05). In addition, preoperative knee kinematics were conserved postoperatively, at a rate of 82% (P<0.01). ConclusionsThe severity of varus knee deformity and the preoperative knee kinematic pattern might have affected the postoperative knee kinematics in PS-TKA. This must be confirmed with a randomized controlled trial on a large population study. Level of evidence: case control study, Level III.

Combined Wedge High Tibial Osteotomy for Large Varus Correction in Patients with Medial Compartment Osteoarthritis

Combined wedge high tibial osteotomy can achieve and maintain an accurate over-correction of great varus knee deformity. Closing and opening wedge high tibial osteotomy (HTO) are established treatment for medial compartment osteoarthritis of knee with varus mal-alignment. Nevertheless, there is a limit for amount of angular correction achieved by both techniques. Combined wedge HTO can achieve accurate over-correction of large varus deformity with few anatomical changes of proximal tibia after 1 year of surgery. Fifty four knees in patients with medial compartment osteoarthritis and big varus mal-alignment (15°) underwent combined wedge HTO with 20° angular correction. Primary outcome measure / endpoint was over-correction of 5° valgus over 1 year after surgery as assessed by hip knee ankle angle (HKA). Secondary objectives were radiological measures of tibial slope (TS), Insall Salvati ratio (IS) and Blackburn Peel ratio (BP) were assessed pre-operatively and 1 year after surgery. Clinical outcome measures; visual analogue scale and KOOS score were measured six weeks, six months and 1 year post-operatively. HKA changed from 5.3° varus to 15.2° valgus (p = 0.000). No statistically significant difference was found in TS (p= 0.9), IS (p=0.75) and BP (p=0.59). Only 3.7% showed patella baja (BP <0.54). 94.7 % of patients were clinically satisfied after 1 year. Combined wedge HTO technique can achieve and maintain accurate correction of large varus deformity of the knee. This relatively new technique can replace external fixators in such a difficult situation.