Similar outcome for total knee arthroplasty after previous high tibial osteotomy and for total knee arthroplasty as the first measure

Muti-factor analysis of sport activity level after high tibial osteotomy

BACKGROUND

Although many studies have shown that high tibial osteotomy is appropriate for active patients, there are limited multifactorial studies on patients' sport activity level after HTO in general population.

METHODS

158 patients who underwent HTO for knee osteoarthritis between January 2016 and December 2019 are included, with a 36-month follow-up. Information was collected from X-rays and questionnaire. The independent variables were age, sex, breadwinner (provide more than 50% income), sport activity level when the knee was pain-free before and after surgery, concomitant meniscal treatment history, Lysholm knee score, desire level for returning to sports. The 158 cases are divided into three groups according to their sports participation before and after operation, Chi-square tests and ANOVA analysis were adopted to identify the effect of these variables on sport activity level after HTO, and factors with statistical differences and clinical relevancies, or provided by previous research were assessed with the ordinal logistic regression analysis.

RESULTS

According to sport activity level analysis, 28(17.7%) patients were categorized into the sport level-reduced group, 97(61.4%) patients into the sport level-unchanged group, and 33(20.9%) patients into the sport level-improved group. Upon ordinal logistic regression analysis, postoperative MA%, age, BMI, and preoperative Lysholm knee score were statistically significant.

CONCLUSIONS

Higher postoperative MA%, younger age, lower BMI, and lower Lysholm score are associate with improvement on activity level after HTO. This finding provides valuable references in operation option and rehabilitation planning.

The Clinical Outcomes of Measured Resection and Gap Balancing Techniques in Primary Total Knee Arthroplasty: A Meta-analysis

BACKGROUND

At present, the clinical efficacy of measured resection (MR) and gap balancing (GB) techniques in total knee arthroplasty (TKA) is still controversial. The objective of this study was to evaluate the clinical outcome indexes of the two surgical methods through a meta-analysis.

METHODS

The literature was systematically searched on PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), WANFANG, Weipu (VIP), and China Biomedical Literature (CBM) electronic databases inception until June 12, 2022. RevMan 5.3 software (the Nordic Cochrane Center, the Cochrane Collaboration, Copenhagen, Denmark) was used to analyze all data of this study. The Cochrane risk bias assessment tool is a risk bias evaluation criterion recommended by the Cochrane Handbook for systematic reviews.

RESULTS

Eleven studies involving 1268 knees in total were included. The main outcome indexes showed that the Knee Society Score (KSS) knee score (MD: -1.40; 95% CI: -2.57 to -0.22; p = 0.02) and KSS knee function score (MD: -3.11; 95% CI: -3.72 to -2.50; p < 0.001) in the GB group were higher 1 year after operation, while femoral component rotation angle (FCRA; MD: -0.75; 95% CI: -1.34 to -0.07; p = 0.03) and the osteotomy volume of the posterior medial femoral condyle (MD: -0.76; 95% CI; -1.13 to -0.38; p < 0.001) were greater in the GB group. In addition, there was no significant difference in the joint line change (MD: -0.03; 95% CI: -0.07 to 0.01; p = 0.16) between the two groups. Secondary outcome results showed that the knee joint range of motion (ROM) in 3 months, and the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score after 1 year were better in the GB group. However, the operation time of the MR group was shorter. In addition, this study revealed no significant differences in post-complications between these two groups.

CONCLUSION

Although the GB technique may not provide better radiographic results or reduce the complication rate, the recovery of joint function showed earlier improvement.

Discharging the medial knee compartment: comparison of pressure distribution and kinematic shifting after implantation of an extra-capsular absorber system (ATLAS) and open-wedge high tibial osteotomy-a biomechanical in vitro analysis

PURPOSE

Young and active patients suffering early degenerative changes of the medial compartment with an underlying straight-leg axis do face a therapeutical gap as unloading of the medial compartment cannot be achieved by high tibial osteotomy. Extracapsular absorbing implants were developed to close this existing therapeutical gap. Purpose of the present cadaveric biomechanical study was to compare the unloading effect of the knee joint after implantation of an extra-articular absorber system (ATLAS) in comparison to open-wedge high tibial osteotomy (OW-HTO) under physiological conditions. The hypothesis of the study was that implantation of an extra-capsular absorber results in an unloading effect comparable to the one achievable with OW-HTO.

METHODS

Eight fresh-frozen cadaveric knees were tested under isokinetic flexion-extension motions and physiological loading using a biomechanical knee simulator. Tibiofemoral area contact and peak contact pressures were measured using pressure-sensitive film in the untreated medial compartment. The tibiofemoral superior-inferior, latero-medial translation and varus/valgus rotation were measured with a 3D tracking system Polaris. Pressures and kinematics changes were measured after native testing, ATLAS System implantation and OW-HTO (5° and 10° correction angles) performed with an angular stable internal fixator (TomoFix).

RESULTS

The absorber device decreased the pressure in the medial compartment near full extension moments. Implantation of the ATLAS absorbing system according to the manufacturers' instruction did not result in a significant unloading effect. Deviating from the surgery manual provided by the manufacturer the implantation of a larger spring size while applying varus stress before releasing the absorber resulted in a significant pressure diminution. Contact pressure decreased significantly Δ0.20 ± 0.04 MPa p = 0.044. Performing the OW-HTO in 5° correction angle resulted in significant decreased contact pressure (Δ0.25 ± 0.10 MPa, p = 0.0036) and peak contact pressure (Δ0.39 ± 0.38 MPa, p = 0.029) compared with the native test cycle. With a 10° correction angle, OW-HTO significantly decreased area contact pressure by Δ0.32 ± 0.09 MPa, p = 0.006 and peak contact pressure by Δ0.48 ± 0.12 MPa, p = 0.0654 compared to OW-HTO 5°. Surgical treatment did not result in kinematic changes regarding the superior-inferior translation of the medial joint section. A significant difference was observed for the translation towards the lateral compartment for the ATLAS system Δ1.31 ± 0.54 MPa p = 0.022 and the osteotomy Δ3.51 ± 0.92 MPa p = 0.001. Furthermore, significant shifting varus to valgus rotation of the treated knee joint was verified for HTO 5° about Δ2.97-3.69° and for HTO 10° Δ4.11-5.23° (pHTO 5 = 0.0012; pHTO 10 = 0.0007) over the entire extension cycle.

CONCLUSION

OW-HTO results in a significant unloading of the medial compartment. Implantation of an extra-capsular absorbing device did not result in a significant unloading until the implantation technique was applied against the manufacturer's recommendation. While the clinical difficulty for young and active patients with straight-leg axis and early degenerative changes of the medial compartment persists further biomechanical research to develop sufficient unloading devices is required.

Measurement for gap balancing technique in patients undergoing total knee arthroplasty: a large retrospective observational study

Background

Many traditional methods are available to prevent unbalance of extension and flexion gap during total knee arthroplasty (TKA), but there are no reports on the use of measurement and positioning method before tibial osteotomy with self-made tools. We designed a self-made tool measuring the location before tibial osteotomy and determined the clinical effect.

Methods

The retrospective study included patients who received TKA at our hospital, between January 1, 2012 and December 31, 2015. A new method, named as the measurement and localization before osteotomy with self-made tools, was developed to measure the osteotomy position of the posterior femoral condyle during TKA. They were divided into two groups, one that received the new method (Group I), and the other that received the traditional method as a control (Group I I). HSS score, Oxford score, VAS score and knee joint activity were evaluated in two groups.

Results

One hundred and eighty-seven of 210 eligible patients were included. The function of knee joint in all patients was improved and the pain was obviously relieved. Significant differences were found in the HSS score, Oxford score, VAS score, knee joint activity between two groups at 5-year follow-up (p < 0.05).

Conclusions

The biomet knee prosthesis was selected for all intraoperative implants. All operations were completed by the same senior surgeon. The use of self-made tools may contribute to improve the balance between flexion and extension gaps as well as the balance between internal and external gaps during TKA, and overcome knee flexion instability.

Body Mass Index Differentially Moderates Heritability of Total Joint Replacement Due to Hip and Knee Osteoarthritis: A Cohort Study of 29,893 Swedish Twin Pairs

BACKGROUND

Osteoarthritis and obesity are diseases with high prevalence, and they share common etiologies. We investigated the sex-specific genetic susceptibility to hip and knee osteoarthritis necessitating total joint replacement (TJR), and how body mass index (BMI) moderated the heritability of these osteoarthritis phenotypes.

METHODS

We linked 29,893 twin pairs with information on BMI in the Swedish Twin Registry with the Swedish National Patient Register to identify twins who underwent primary TJR of the hip or knee combined with a concomitant diagnosis of primary osteoarthritis of these joints. Structural equation modeling was used to calculate the heritability of hip and knee osteoarthritis treated with TJR, with estimates adjusted for the first available BMI, birth year, and sex. We also investigated how heritability varied with BMI treated as a continuous variable.

RESULTS

Similar heritability estimates for hip replacement (0.65 [95% confidence interval (CI), 0.59 to 0.70]) and knee replacement (0.57 [95% CI, 0.50 to 0.64]) were found. Heritability decreased with higher BMI in both sexes for hip replacement and in men for knee replacement. In contrast, heritability for knee replacement increased with higher BMI in women; the estimate was 0.37 (90% likelihood interval [LI], 0.25 to 0.49) for a BMI of 20 kg/m2 and 0.87 (90% LI, 0.68 to 0.94) for a BMI of 35 kg/m2.

CONCLUSIONS

In our population, heritability explained, on average, about half of the susceptibility to undergo primary TJR of the hip or knee with the indication of primary osteoarthritis, but it varied with BMI and sex. We demonstrated substantial heritability for knee replacement in obese women.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison of the efficiency of an extra-articular absorber system and high tibial osteotomy for unloading the medial knee compartment: an in vitro study

PURPOSE

The unloading effect of an extra-articular absorber system on the knee joint medial compartment was compared with high tibial osteotomy (HTO) under physiological conditions in vitro.

METHODS

Seven fresh-frozen cadaveric knees were used to test isokinetic flexion-extension motions under physiological loading using a biomechanical knee simulator. Tibiofemoral area contact and peak contact pressures were measured using pressure-sensitive film in the untreated medial compartment. Pressures were measured after KineSpring System implantation and HTO (5° and 10° correction angles) performed with an angular-stable internal fixator (Tomofix).

RESULTS

Implantation of the unloading device resulted in significantly decreased medial compartment area contact pressure (Δ0.02 ± 0.01 MPa, p = 0.001) and peak contact pressure (Δ0.3 ± 0.1 MPa, p = 0.001) compared with the first test cycle results in the untreated knee. HTO significantly decreased the pressure (p = 0.001). Compared with the first test cycle, HTO (5° correction angle) decreased the mean contact pressure by Δ0.03 ± 0.01 MPa and peak contact pressure by Δ0.3 ± 0.01 MPa. With a 10° correction angle, HTO decreased contact pressure by Δ0.04 ± 0.02 MPa and peak contact pressure by Δ0.4 ± 0.1 MPa compared with that at the 5° correction angle.

CONCLUSION

Implantation of an extra-capsular unloading device resulted in a significant unloading effect on the medial compartment comparable to that achieved with HTO at 5° and 10° correction angles. Thus, implantation of an extra-articular, extra-capsular absorber could become the method of choice when treating patients with unicompartmental osteoarthritis that cannot be adequately treated by HTO because of their straight-leg axis.

The relationship between pain with walking and self-rated health 12 months following total knee arthroplasty: a longitudinal study

BACKGROUND

A subgroup of patients continue to report pain with walking 12 months after total knee arthroplasty (TKA). The association between walking pain and self-rated health (SRH) after TKA is not known. This prospective longitudinal study aimed to investigate the association between a comprehensive list of preoperative factors, postoperative pain with walking, and SRH 12 months after TKA.

METHODS

Patients (N = 156) scheduled for TKA completed questionnaires that evaluated demographic and clinical characteristics, symptoms, psychological factors, and SRH. SRH was re-assessed 12 months after TKA. Clinical variables were retrieved from medical records. Pain with walking was assessed before surgery, at 6 weeks, 3, and 12 months after TKA. Subgroups with distinct trajectories of pain with walking over time were identified using growth mixture modeling. Multiple linear regression was used to investigate the relationships between pain with walking and other factors on SRH.

RESULTS

Higher body mass index, a higher number of painful sites at 12 months, recurrent pain with walking group membership, ketamine use, higher depression scores, and poorer preoperative self-rated health were associated with poorer SRH 12 months after TKA. The final model was statistically significant (p = 0.005) and explained 56.1% of the variance in SRH 12 months after surgery. SRH improved significantly over time. Higher C-reactive protein levels, higher number of painful sites before surgery, higher fatigue severity, and more illness concern was associated with poorer preoperative SRH.

CONCLUSIONS

In patients whose walking ability decreases over time, clinicians need to assess for unreleaved pain and decreases in SRH. Additional research is needed on interventions to improve walking ability and SRH.