Severe Varus Knee Research Articles

The amount of femorotibial alignment correction through total knee arthroplasty may affect postoperative hindfoot alignment.

This study was performed to investigate the relationship between the amount of femorotibial alignment correction and the amount of improvement of hindfoot alignment in total knee arthroplasty (TKA). A total of 159 knees undergoing TKA in 120 patients were assessed preoperatively and at 2 weeks, 1 month, 3 monthsand 6 months postoperatively. Standing hindfoot alignment was evaluated using the leg-heel angle (LHA). The amount of change in hindfoot alignment was compared between patients with severe varus knee (Group 1) and those with moderate varus, neutralor valgus knee (Group 2). The mean values of pre- and postoperative hip-knee-ankle (HKA) angle were -14 ± 4° and -1 ± 3° in Group 1 and -7 ± 5° and -1 ± 3° in Group 2, respectively. The differences between pre- and postoperative LHA were significantly larger in Group 1 than in Group 2 at 2 weeks, 1 monthand 3 months postoperatively (p = 0.006, 0.001and 0.03, respectively). At 6 months postoperatively, no differences were observed between the two groups (p = 0.31). The amount of change in hindfoot alignment was larger in Group 1 than in Group 2 at 2 weeks, 1 monthand 3 months after TKA, but there was no significant difference between the two groups at 6 months after TKA. Prognostic Level II.

The relationships among knee and patella alignments, body mass index, quadriceps, and knee adduction moments in healthy young females

ObjectiveTo determine the relationships among knee and patella alignments, BMI, quadriceps, and knee adduction moments, which are associated with knee osteoarthritis, in healthy people. MethodsIn 60 young females, intercondylar distances normalized by body height, Q-angle, and BMI were assessed. The ratios of individual muscle:quadriceps thicknesses measured using ultrasonography were calculated. Correlations between these parameters were evaluated. Ten subjects were selected from the VALGUS, mild VARUS, or severe VARUS knee groups (<1.5 %, 1.5 %≤normalized intercondylar distance<2.0 %, and 2.0 %≤, respectively). The external knee adduction moments measured by three-dimensional gait analysis were compared among the 3 groups, and the correlations with BMI, the Q-angle, and the individual quadriceps thickness ratios were evaluated for each of the 3 groups. ResultsThe normalized intercondylar distance and Q-angle increased as the vastus medialis:quadriceps thickness ratio increased (r = 0.29 and r = 0.28, respectively), while BMI increased as the vastus medialis:quadriceps thickness ratio decreased (rs = −0.59) and the rectus femoris:quadriceps thickness ratio increased (rs = 0.34). The knee adduction moment in the severe VARUS was greatest (effect size = 2.1 versus the VALGUS; effect size = 1.7 versus the mild VARUS); however, the knee adduction moment increased as the vastus medialis:quadriceps thickness ratio decreased (r = −0.68) and the rectus femoris:quadriceps thickness ratio increased (r = 0.66) in the mild VARUS, whereas the knee adduction moment increased as the Q-angle decreased in the severe VARUS (rs = −0.83). ConclusionThe vastus medialis:quadriceps thickness ratio was related to knee and patellar alignment and BMI. The mechanism by which the knee adduction moment is reduced differs according to the degree of knee alignment.

Preserving primary medial static stabilizer ligaments achieves physiological knee kinematics in total knee arthroplasty

PurposeAs postoperative knee instability has been reported to be one of the critical reasons for early failure in total knee arthroplasty (TKA), obtaining optimal knee stability—especially in medial—was indispensable for successful TKA. We hypothesized that preserving medial soft tissue structures was the key to maintain physiological medial knee stability. Thus, TKAs with preserving primary medial static stabilizer ligaments technique were performed, and the postoperative knee kinematics was evaluated. MethodsPrimary knee osteoarthritis patients with varus knee deformity and planed for primary TKA were enrolled. However, patients with severe varus knee deformities, valgus knee deformities, and rheumatoid arthritis were excluded. TKAs were performed by removing medial femoral and tibial osteophytes; however, the primary medial static stabilizer ligaments—the superficial medial collateral ligament (MCL), deep MCL, and posterior oblique ligament—were not released. The cruciate-retaining (CR), posterior-stabilized (PS), and medial-pivot (MP) inserts were implanted, and the knee kinematics was measured. These data were statistically analyzed using analysis of variance. The institutional review board approved the study. ResultsFrom full extension to maximum flexion, the lateral femoral condyle moved backward, greater than the medial femoral condyle, and consequently the femur external rotated on the tibia. These kinematics patterns were shown in CR, PS, and MP groups. ConclusionAs the knee kinematics of CR and PS are similar to that of MP, which has been reported to demonstrate physiological knee kinematics, preserving primary medial static stabilizer ligaments technique could potentially preserve physiological knee kinematics.

Comparison of ultra-congruent anterior-stabilized vs. a posterior cruciate substituting total knee arthroplasty for osteoarthritis with severe varus knee deformity: comparable 2 year outcomes with two design.

In this retrospective study, we compared the functionality and clinical outcomes of patients with severe varus knees who underwent total knee arthroplasty (TKA) that used prostheses with either a posterior stabilized (PS) design or an ultra-congruent (UC) design. Primary TKA was performed in 161 patients; the UC device was used in 82 (51%) cases and the PS device in 79 (49%). Preoperatively and at the final follow-up examination, all patients were evaluated by orthoroentgenography. The mechanical axis angle and radiolucent lines were evaluated according to the Knee Society Roentgenographic Evaluation System on preoperative and 5-year follow-up radiographs. Total Knee Society Score (KSS) (knee score/function score) and Visual Analog Scale scores were obtained at the final follow-up examination. Demographic and surgical data and revision rates were evaluated for all patients. Postoperative angle values were significantly decreased in both the UC and PS groups (p<0.001 and p<0.001, respectively). Postoperative flexion range of motion values were significantly increased in both the UC and PS groups (p<0.001 and p<0.001, respectively). The postoperative KSS function scores were not significantly different between the groups (p=0.194). The mean surgical time of the PS group (54.99±4.18 minutes) was significantly higher than that of the UC group (46.02±4.48 minutes) (p<0.001). No notable differences were found between the UC and PS groups with respect to the clinical and functional parameters examined. Based on these results, UC TKA can be considered a safe alternative to PS TKA in severe varus knees.

Value of personalized osteotomy in primary total knee arthroplasty for severe varus knee osteoarthritis

To explore application value and efficacy of personalized osteotomy in primary total knee arthroplasty (TKA) for severe varus knee osteoarthritis. From June 2018 to January 2020, 36 patients (49 knees) with severe varus knee osteoarthritis were treated, including 15 males (21 knees) and 21 females (28 knees), aged from 59 to 82 years old with an average of (67.6 ± 6.5) years old;the course of disease ranged from 9.5 to 20.5 years with an average of (15.0 ± 5.0) years;11 patients (15 knees) with Kellgren-Lawrence grade Ⅲ and 25 patients (34 knees) with grade Ⅳ according to Kellgren-Lawrence grading. According to AORI clsssification of tibial bone defects, 8 patients (15 knees) were typeⅠTa and 16 patients (18 knees) were typeⅡ T2a. All patients' femor-tibial angle (FTA) was above 15°, and received primary TKA with personalized osteotomy. Thirty-three patients (45 knees) were treated with posterior-stabilized (PS) prostheses, 13 patients (15 knees) with PS prostheses combined with a metal pad and extension rod on the tibial side, and 3 patients (4 knees) with legacy constrained condylar knee (LCCK) prostheses. FTA, posterior condylar angle (PCA), medial proximal tibial angle (MPTA) and lateral distal femoral angle (LDFA) before and after operation at 1 month were measured and compared by using picture archiving and communication systems (PACS). Recovery of lower limbs before and after operation at 12 months was evaluated by American Knee Society Score(KSS), and complications were observed and recorded. All 36 patients (49 knees) were followed up from 15 to 40 months with an average of (23.46±7.65) months. FTA, MPTA were corrected from preoperative (18.65±4.28)° and (83.75±3.65)° to postoperative (2.35±1.46)° and (88.85±2.25)° at 1 month, respectively (P<0.001). PCA was decreased from (2.42±2.16)° before operation to (1.65±1.35)° at 1 month after operation, LDFA improved from (89.56 ± 3.55)° before operation to (91.63±3.38)° at 1 month after operation (P<0.05). KSS increased from (67.58±24.16) before opertion to(171.31±15.24) at 12 months after operation, 14 patients (19 knees) got excellent result, 19 (26 knees) good, and 3 (4 knees) fair. Personalized osteotomy is helpful for recovery of axial alignment of lower limbs and correct placement of prosthesis, could effectively relieve pain of knee joint, recover knee joint function.

Primary constrained condylar knee arthroplasty in severe varus deformity: a prospective 5-year functional follow-up study in Iraqi patients.

The outcomes of the constrained condylar knee (CCK) implant used during primary total knee arthroplasty (TKA) in knees with severe varus in patients from low- and middle-income countries (LMICs) such as Iraq are not known. Hence, this study aimed to analyze and report the functional outcome of CCK TKA in patients with severe varus deformities at the end of 5 years in Iraqi patients. In this prospective study, pre- and post-operative (at the end of 5years) clinical outcome using Knee Society Score (KSS) and radiological deformity using hip-knee-ankle (HKA) angle was analyzed in 76 CCK TKAs (20 bilateral and 36 unilateral TKAs) performed in 56 patients with severe varus deformity (> 15°). At a mean follow-up of 60.3months (range 60-68months), the mean preoperative KSS knee score of 6.6 ± 4.5 improved significantly (p < 0.0001) to 87.2 ± 6.6 and the mean preoperative KSS function score of 7.1 ± 6.4 improved significantly (p < 0.0001) to 70.4 ± 7.8. The function score was good to excellent in 64.3% (36 patients), fair in 28.5% (16 patients), and poor in 7.1% (4 patients) at the end of 5years. The mean preoperative HKA angle significantly improved (p < 0.001) from 25.5° ± 6° varus (range 17°-37°) to 3° ± 2.5° varus (range 0°-7.5°) at final follow-up. The CCK implant significantly improved pain and function in patients with severe varus deformity at the end of 5years. The CCK implant is a good option during primary TKA in severe varus knees in patients from LMICs and can help achieve clinical outcomes similar to patients from high-income countries.

Clinical and Radiological Comparison of Single and Double Intra-articular Injection of Adipose-Derived Stromal Vascular Fraction for Knee Osteoarthritis

The aim of the article is to compare the clinical and radiological outcomes between single and double stromal vascular fraction (SVF) cell injections in patients with knee osteoarthritis (OA). We included 54 patients treated for varus knee OA with intra-articular SVF cell injection. They were divided into two groups: those who received one injection and those who received two. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, knee range of motion, and knee muscle force were assessed at baseline and 3, 6, 12, and 24 months after the first injection. The preoperative hip-knee-ankle (HKA) angle was evaluated using plain radiographs, and T2 mapping values were assessed. The total WOMAC score improved significantly in the single injection group from 3 to 24 months, but the total WOMAC score in the double injection group improved significantly at 24 months. The T2 mapping values in both the groups improved, with a significant difference at 12 months. The preoperative mean HKA angle and the correlation coefficients between the HKA angle and the total WOMAC score and between the HKA angle and the T2 mapping value of the medial femur were significant. In conclusion, double injections may provide more satisfactory treatment outcomes in patients with severe varus knee alignment. This clinical trial is registered in the Japanese Ministry of Health, Labour and Welfare (URL: https://saiseiiryo.mhlw.go.jp/published_plan/index/2) with the registration name “Cell transplantation therapy for osteoarthritis using autologous subcutaneous adipose tissue-derived regenerative (stem) cells (ADRCs),” and the registration number was “PB5160012.”

The severity of preoperative varus deformity affects the feasibility of correcting lower limb alignment with medial unicompartmental knee arthroplasty

BackgroundThe relationship between the severity of preoperative varus deformity and the amount of its correction in unicompartmental knee arthroplasty (UKA) as well as the thickness of the insert has not been well known. MethodsOne hundred and three patients who underwent medial fixed-bearing UKA with the use of the spacer block method were assessed. After the component gap in extension was measured using a UKA tensor, the pre-osteotomy gap was calculated from the thickness of the bone cuts. The relationship between the preoperative hip–knee–ankle (HKA) angle as well as the pre-osteotomy gap and the amount of change in HKA angle were analysed. Also, preoperative HKA angle and the thickness of the bone cuts were compared among groups by the insert thickness. ResultsThe mean preoperative HKA angle was 7.7 ± 3.1° varus. Patients with more varus deformity and those with a wider pre-osteotomy gap showed a more valgus change in HKA angle. As for the thickness of the insert, the preoperative HKA angle of the patients with the thinnest insert was significantly smaller (less varus) than that of those with the thicker insert while no statistically significant difference was found among the insert groups regarding the amount of the bone cuts. ConclusionsThe severity of the preoperative varus deformity as well as the intraoperative pre-osteotomy gap related to the amount of change in HKA angle. As thick inserts tended to be used in severe varus knees, the tibial bone cut can be reduced in such cases.

Factors Associated With Unfavorable Radiological Outcomes After Opening-Wedge High Tibial Osteotomy for Varus Knees.

Corrective osteotomy around the knee is based on deformity profiles of the femoral and tibial sides. Opening-wedge high tibial osteotomy (OWHTO) can be favored if the outcomes are not different, even if there is a certain degree of abnormal parameters after correction. The purpose of this study was to identify the factors associated with unfavorable radiological outcomes after OWHTO for varus knees. Our hypothesis was that there would be an optimal situation in which double-level osteotomy (DLO) has advantages over isolated OWHTO and an optimal cutoff value of structural parameters for which DLO should be considered in patients with severe varus knees. Case-control study; Level of evidence, 3. The radiological and clinical outcomes of 337 patients who underwent OWHTO were retrospectively evaluated. A subgroup analysis was performed according to the weightbearing line ratio (WBLR) (group 1: <25th percentile; group 2: 25th-75th percentile; and group 3: >75th percentile) and factors associated with unfavorable radiological outcomes. For the assessment of cutoff values of the parameters favoring DLO, unfavorable radiological outcomes were categorized as follows: (1) medial proximal tibial angle (MPTA) >95°, (2) joint-line convergence angle (JLCA) >4° (insufficient medial release), (3) JLCA <0° (medial instability), (4) recurrence of a varus deformity, and (5) lateral hinge fracture. The mean follow-up period was 66.2 ± 19.1 months. A low preoperative WBLR was related to a larger preoperative to postoperative change (Δ) in the WBLR, a larger reduction in coronal translation, a larger ΔMPTA, a wide preoperative lateral joint space, and a narrow preoperative medial joint space (P < .001, P < .001, P < .001, P = .016, and P = .003, respectively). However, only an MPTA >95° was significantly related to a low WBLR in the subgroup analysis according to unfavorable radiological outcomes (P = .038). The cutoff value of ΔWBLR causing an MPTA >95° was 46.5%, which showed a good area under the curve of 0.800, with a sensitivity of 74.4% and a specificity of 82.7%. The clinical outcomes significantly improved at the final follow-up compared with those preoperatively, with no significant differences between the WBLR groups. A ΔWBLR ≥46.5% led to an MPTA >95°. However, clinical outcomes were not affected. DLO should be considered if the surgeon desires a postoperative MPTA ≤95°.

Accuracy of the Tibial Component Alignment by Extramedullary System Using Simple Radiographic References in Total Knee Arthroplasty.

Background and Objectives: The tibial component alignment is an important issue for the longevity of total knee arthroplasty (TKA). The purpose of our study was to investigate the usefulness of proximal tibial references determined by pre-operative radiography and intraoperative C-arm-guided hip and ankle center marking for the extramedullary guided tibial cut in mild (<10°) and severe (≥10°) varus knee TKA. Materials and Methods: A total of 150 consecutive patients (220 cases) who underwent total knee arthroplasty who were recruited from July 2011 to April 2017 were reviewed retrospectively. Before surgery, the proximal tibial reference point and medio-lateral cut thickness difference were identified. Then, hip and ankle centers were checked using a C-arm intensifier intraoperatively. The hip–knee–ankle (HKA) alignment and medial proximal tibial angle (MPTA) were assessed pre-operatively and post-operatively. More than 3° varus or valgus of HKA alignment or tibial component angle was defined as an outlier. Results: Mean follow-up duration was 26.9 months. Among 220 cases, 111 cases are classified as mild varus group and 109 cases are classified as severe varus group. The HKA alignment is significantly improved (p < 0.001). The average tibial component angle after surgery is 90.1°. A total of 21 cases (9.5%) and 3 cases (1.4%) are classified as outliers of HKA alignment and MPTA, respectively. Among MPTA outliers, one case is in the mild varus group and two cases are in the in severe varus group (p = 0.62). Conclusion: Measurement of proximal tibial radiographic references and checking the C-arm-guided intraoperative hip and ankle center could be helpful to obtain the favorable coronal position of the tibial component in the extramedullary guided tibial cut.

Simultaneous Femoral Osteotomy and Primary Total Knee Arthroplasty in Patient with Severe Extra-articular Deformity : A Case Report

Correction of an extra-articular deformity of the femur and tibia during total knee arthroplasty (TKA) in advanced knee osteoarthritis (OA) is a technically demanding procedure. The challenge is in the implications of the femoral and tibial realignment osteotomy in both coronal and sagittal planes either as step-by-step or simultaneous procedure. We herein describe an unusual case of knee OA characterized by fixed severe varus knee deformity, tibio-femoral bowing, and lower limb internal rotation. The patient underwent distal femoral osteotomy correction accompanied by TKA to restore mechanical and rotational alignment at the same time. A standard primary posterior stabilized (PS) implant was used. The procedure successfully provided stability, restored alignment and delivered good functional outcome. This case highlights the arthroplasty surgeon’s challenges, especially those who work in limited facilities.

Clinical Outcomes of Repair of Complete Detachment of Medial Collateral Ligament at the Tibial Insertion in Bilateral Total Knee Arthroplasty.

Purpose Complete detachment of the medial collateral ligament (MCL) may occur during medial release of total knee arthroplasty (TKA) in patients with severe varus knee osteoarthritis. This study was to determine functional and stability outcomes of repaired knee with complete detachment of MCL compared to those of contralateral nondetached MCL in patients with bilateral TKA. Methods Records of 1052 consecutive knees undergoing bilateral TKA from 2003 to 2015 were retrospectively reviewed. Of which, 45 patients were repaired for complete MCL detachment injury (2.1%) at tibial insertion in one side (repaired group). MCL was not detached in the contralateral side (control group). Clinical evaluation was performed preoperatively and at the final follow-up using KS and WOMAC scores between two groups. Similarly, stability was compared on a valgus stress radiograph between two groups. Results Two patients had insufficient data. Hence, 43 patients were included after a minimum of 5 years follow-up. There were no significant differences in terms of alignment and clinical outcomes between the two groups either preoperatively or at the final follow-up (p > 0.05). Radiographic stability also showed no differences between repaired and control groups in extension and 30° of flexion (p=0.208 and p=0.125). Conclusions For tibial detachment of the MCL during TKA, repair with suture anchor provided good clinical and stability results, similar to TKA without MCL injury. Therefore, repair with a suture anchor is a reliable method that provides good clinical and stability outcomes in patients with MCL injury during TKA.

Total Knee Arthroplasty Using Adjusted Restricted Kinematic Alignment for the Treatment of Severe Varus Deformity: Technical Note.

ObjectiveTo describe a new alignment technique of adjusted restricted kinematic alignment (arKA) for the treatment of severe varus deformity in total knee arthroplasty.MethodsThree female patients (three severe varus knees) who underwent navigation‐assisted total knee arthroplasty (TKA) using arKA from April 2020 to September 2020 were included in this study, with an average age of 71.33 years (range, 61 to 80 years). General anesthesia was given to all patients. Intraoperative observations including tibia resection angle, frontal femoral angle, axial femoral angle, medial and lateral gap in the extension and flexion positions and joint line translation were recorded. Also, operation duration and drainage volume were recorded. Radiographic parameters including the mechanical axis (α), coronal femoral component angle (β), coronal tibial component angle (γ), sagittal femoral component angle (δ), tibial posterior slope angle (ε), femoral‐patella angle (θ), and femoral notching were assessed. Clinical evaluation was performed using the Hospital for Special Surgery (HSS) Score and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Score. Both individual and mean measurement data were displayed.ResultsThe mean tibial resection was 4.00° varus (range, 3° to 5°), and the mean frontal femoral angle was 3.67° varus (range, 3° to 4°) in extension. The flexion lateral gap was wider than the medial gap with a mean laxity of 1.34 mm. Moreover, the mean axial femoral angle was 2.67° external (range, 0° to 6°) in flexion, and the mean joint line translation was 1.00 mm proximal (range, 0 to 3 mm). In addition, the mean preoperative mechanical axis was 156.22° (range, 153.65° to 158.90°) and the mean postoperative mechanical axis was 174.04° (range, 173.83° to 174.17°) with a mean correction of 17.82°. The mean femoral angle was 92.60° (range, 91.29° to 93.30°) and the mean tibial angle was 86.95° (range, 86.83° to 87.04°) in coronal plane. The HSS score improved from an average of 46.67 points (range, 42 to 51) preoperatively to 83.67 points (range, 81 to 86) at 3 months postoperatively. The mean WOMAC score was 16.33 points at 3 months postoperatively.ConclusionsThe new alignment technique of arKA aims to balance the flexion and extension gap without extensive releases of soft tissue and restore the native pre‐arthritic alignment, may be a promising alignment strategy for treating severe varus deformity. However, further study and comparison with other alignment techniques is needed.

Comparison of Survival Rate and Outcomes Between Conventional and Navigation-Assisted Primary Total Knee Arthroplasty in Severe Varus Knees: A Minimum 10-Year Follow-Up

BackgroundThis study aimed to compare the long-term clinical and radiographic outcomes and survival rates between navigation-assisted (NAV) total knee arthroplasty (TKA) and conventional (CON) TKA in patients with preoperative severe varus deformity. MethodsFrom January 2005 to December 2011, 152 TKAs and 62 TKAs with preoperative hip-knee-ankle (HKA) angles more than 15° were enrolled in the CON-TKA and NAV-TKA group with 135.7 months follow-up. Clinical outcomes (Western Ontario and McMaster University Osteoarthritis Index and Knee Society Scores), radiographic outcomes (HKA, α, β, γ, and δ angles), and survivorship were compared between the groups. ResultsThe mean value of radiographic outcomes was not statistically different; however, outliers of the HKA angle were significantly higher in the CON-TKA group (18.4% versus 8.1%, P = .04). However, long-term clinical outcomes were similar between both groups. The cumulative survival rate was 96.1% in the CON-TKA group and 96.8% in the NAV-TKA group, with no difference between the groups (P = .962). ConclusionNAV-TKA showed fewer outliers in the HKA angle for severe preoperative varus deformity compared with CON-TKA. The long-term clinical outcomes and survival rates were similar between the 2 techniques. A survival rate of more than 96% was observed in both groups. Study DesignLevel III, retrospective comparative study.

A rare case of bilateral periprosthetic fracture of medial condyle of tibia after total knee arthroplasty

Introduction: Bilateral periprosthetic fractures of medial condyle of tibia after total knee arthroplasty are of rare incidence, as evident from previous literature. The risk factors include morbid obesity, low bone mass or osteopenia, prolonged use of corticosteroids or even trivial trauma leading to stress fractures. Case Report: We reported a case of bilateral periprosthetic fracture tibia after primary total knee arthroplasty in a patient with severe varus knees and morbid obesity. X-Ray [AP view of knee] and orthoscanograms revealed the fracture; SPECT CT showed evidence of aseptic inflammation and component loosening [Type 1B fracture; Felix Classification]. Revision arthroplasty was done with an augmented long-stem implant and the patient was discharged after a normal postoperative phase on the 10th day. Knee movement at 6 months was 0-120 degrees with satisfactory outcome scores on follow-up. Discussion: The incidence of bilateral periprosthetic fractures of tibia after primary knee arthroplasty are of rare occurrence, and often associated with severe varus malalignment and morbid obesity. Obesity leads to excessive joint overloading, and together with varus malalignment may lead to component loosening, requiring revision arthroplasty. Conclusion: Even though bilateral periprosthetic tibial fractures are rare, immediate diagnosis and treatment is necessary, if associated with varus knees and morbid obesity after primary total knee arthroplasty. Reduction of weight is mandatory before primary total knee arthroplasty to improve the functional outcomes and reduce the incidence of revision arthroplasty.

Application of sliding osteotomy in total knee arthroplasty for patients with extra-articular femoral deformity

In order to observe the clinical effects of sliding osteotomy for patients with severe knee osteoarthritis and varus knee due to complex femoral extra-articular deformity to achieve the medial and lateral soft tissue balancing during total knee arthroplasty. From June 2014 to January 2018, a total of 22 patients with severe knee osteoarthritis and complex extra-articular malformation of femurs were treated with total knee arthroplasty. There were 5 males and 17 females in this group, aged 48 to 76 years old, with an average age of (61.3±13.8) years old. All the patients had varus deformities caused by extra-articular deformities of femur. Hip-knee-ankle(HKA) angle was(158.8±9.7) ° before operation, and the average Knee Society Score (KSS) clinical score was 32.6±6.1;KSS function score was 35.8 ±9.6;the average Hospital for Special Surgical (HSS) score was 39.7±4.6;the average range of motion before operation was (80.6±10.7) °. The mechanical alignment method was used in joint replacement. The flexion space was balanced first. The coronal plane vertical sliding osteotomy was performed on the medial femoral condyle for the imbalance of coronal plane. The sliding distance of the osteotomy block was determined by straightening the gap between the inner and outer sides of the space until the space was balanced. After the separated segments were fixed with several screws, the prosthesis was installed as usual. The wounds of all patients healed in the first stage, and no wound complications occurred. All the 22 patients were followed up, and the duration ranged from 18 months to 3 years with an average of (28.2±10.1) months. X-ray showed that the fracture line disappeared for 2 to 5(3.5±1.5) months without nonunion. HKA angle measured at the latest follow up was (178.8±0.7) °, which wassignificantly different from that before operation. The HSS score was 91.3 ±6.0;KSS clinical score 93.7±3.5;KSS functional score 81.2±6.5;and the average range of motion of knee joint was(121.7±11.6) °, which was statistically significant compared with that before operation. For severe knee osteoarthritis patients with complex femoral extra-articular deformity, sliding osteotomy is performed. For severe varus deformity, downward sliding the medial femoral condyle is performed. The operation is relatively simple and the damage is small. It is easy to achieve the balance of internal and external soft tissue in flexion extension space. The short-term clinical effect is satisfactory.

Double-level osteotomy for severe varus osteoarthritic knees can prevent change in leg length and restore physiological joint geometry

BackgroundIt is unclear whether double-level osteotomy (DLO) combining closed-wedge osteotomy in the distal femur and open-wedge osteotomy in the proximal tibia deformity can prevent change in leg length and excessive coronal inclination of the tibial articular surface in surgical correction of the severe varus knee. The purpose of this study was to examine the postoperative change in leg length as well as radiological and clinical outcomes following DLO compared with the results obtained from knees undergoing isolated open-wedge high tibial osteotomy (OW-HTO). MethodsIn cases of severe varus knee deformity (hip–knee–ankle angle (HKA) > 10°) 29 patients undergoing DLO and 35 patients undergoing OW-HTO were included. If the predicted mechanical medial proximal tibial angle (mMPTA) was 95° or greater or the wedge size was 15 mm or greater in the surgical simulation, then DLO was considered as the surgical of option. In cases where these criteria were not met, OW-HTO was selected. All patients were followed up for a minimum of 2 years. ResultsThe changes in the length of the whole leg in the DLO and OW-HTO groups averaged 2.3 ± 4.8 mm and 9.3 ± 7.2 mm, respectively (P < 0.001). mMPTA of more than 95° was found in no knee in the DLO group. ConclusionsThis study showed that DLO could avoid leg length change and non-physiologic joint lines when performed in patients with varus HKA > 10°, and the predicted mMPTA was 95° or greater or the wedge size was 15 mm or greater in the surgical simulation.

Calcaneal insufficiency fractures following ipsilateral total knee arthroplasty

IntroductionOnly a few reports have described calcaneal insufficiency fractures (IFs) following total knee arthroplasty (TKA). Herein, we describe nine cases of calcaneal IFs following ipsilateral TKA. The purpose of this study was to investigate the incidence of calcaneal fractures following TKA and determine the characteristics of patients with IFs. Patients and methodsWe retrospectively investigated cases of calcaneal IF that occurred following TKA. We collected and analyzed radiographic and magnetic resonance imaging (MRI) findings as well as patient demographic data. We compared the demographic data, bone mineral density (BMD), and preoperative hip-knee-ankle angle (HKA) between cases with a calcaneal fracture following TKA and 100 cases without a fracture following TKA. ResultsWe performed a total of 1548 knee arthroplasties at our clinic from 2011 to 2020. Nine calcaneal IFs in eight patients were diagnosed following ipsilateral TKA. All patients were women with varus knee osteoarthritis (mean age, 71.8 years). The average change in the alignment angle was 14.7° ± 5.4°. In eight cases, dysfunction was observed in the opposite lower limb. The postoperative onset of hindfoot pain started at an average of 5.6 months. In seven patients, calcaneal fractures occurred idiopathically, but in one patient, two fractures occurred after long-distance walking. No abnormal findings on a calcaneus radiograph were seen for six fractures. MRI demonstrated a definite fracture line and bone marrow edema in all patients. All patients, except one with type 2 diabetes mellitus (T2DM), had osteoporosis. Fractures healed without complications in eight patients; however, the calcaneal anterior facet fracture became displaced and caused a flat foot in one case. The calcaneal IF rate was 0.58% among all cases. Besides one case with T2DM, significant differences were observed in preoperative HKA and BMD between cases with a calcaneal fracture following TKA and those without a fracture. ConclusionsA change in the load on the calcaneus due to changes in the alignment of the lower extremities after TKA may cause calcaneal IFs. Orthopedic surgeons should be aware of the possible occurrence of calcaneal IFs following TKA, especially in women with osteoporosis and severe varus knee.

A new double level osteotomy procedure to restore a joint line and joint angles in severe varus osteoarthritis. - Double level osteotomy associated with tibial condylar valgus osteotomy (DLOTO)

High tibial valgus osteotomy (HTO) is a well-established surgical procedure to correct a varus malalignment and treat medial compartment osteoarthritis. Recently, double level osteotomy (DLO) was recommended for extensive varus knees as a single level osteotomy (SLO) approach may create an excessive joint line obliquity and eventually result in a new bony deformity. However, a severe varus knee in cases of advanced osteoarthritis involves not only a bony deformity (extra-articular deformity) but also a medial joint space narrowing with a widened lateral joint space (intra-articular deformity). A DLO alone cannot reduce this intra-articular deformity. However, tibial condylar valgus osteotomy (TCVO) can complement DLO as to reduce this intra-articular deformity. This technical note describes a novel modified DLO procedure associated with TCVO which can restore a normal alignment and a joint line and achieve joint preservation even in cases of extensive varus osteoarthritis.

The Effect of Total Knee Arthroplasty on Hindfoot Alignment in Patients with Severe Genu Varum and Genu Valgum.

The maintenance of deformity in the ankle and hindfoot after correction of knee deformity following knee arthroplasty may cause abnormal tension in the knee and patient dissatisfaction. The aim of this study was to determine the effect of knee arthroplasty on the hindfoot alignment in patients with severe genu varum and valgum. A total of 84 patients with primary osteoarthritis, were enrolled in the study. The knee deformity was measured using a long leg film before surgery. The long axial radiographic view of hindfoot was taken in the standing position for all patients, before and six months after surgery. Comparisons were made on changes in the hindfoot angles measured before and after surgery. A total of 84 patients with mean age of 62.28 ± 7.77 years, 77 (92%) and seven patients (eight percent) had knee varus and valgus deformity, respectively. In the knee varus group, the mean preoperative hindfoot angle was + 5.32 ± 6.12 ° (valgus) which was changed to - 0.25 ± 4.91 ° (varus) in the postoperative phase. In the knee valgus group, the mean pre and postoperative hindfoot angles were - 7.71 ± 7.06° (varus) and - 2.14 ± 5.92 ° (varus), respectively. The mean preoperative hindfoot angle in severe and very severe varus knee groups were + 5.45 ± 3.30 and + 5.28 ± 6.86 °, respectively. These angles were changed to + 0.21± 5.17 and -1.60 ± 3.89° six months after surgery, respectively. The mean preoperative hindfoot angle in severe and very severe valgus knee deformity groups were - 7.00 ± 4.69 and -8.66 ± 10.69 °, respectively. These angles were changed to - 2.00 ± 5.71 and - 2.33 ± 7.50 °after surgery, respectively. There was no significant difference between patients with severe and very severe deformity in terms of pre and post-operative hindfoot angle. The hindfoot alignment is significantly corrected after knee arthroplasty. The severity of knee deformity does not correlate with the severity of the hindfoot deformity before and after surgery.