Trunk control,motion and alignment after total knee arthroplasty: a systematic review and meta-analysis

BackgroundTrunk control improves mobility, balance and quality of life early after total knee arthroplasty (TKA) and is therefore considered an important parameter during the recovery process. However, little is known about trunk control, motion and alignment after TKA. Increasing our understanding aids in optimizing treatment strategies to enhance functional mobility after TKA.Research questionDoes trunk control, motion and alignment return to normal after TKA and is this related to functional mobility?MethodsFive scientific databases were searched until July 2021. Eligibility criteria consisted of outcomes assessing trunk control and alignment in a population of adults undergoing TKA. Two reviewers independently screened studies and risk of bias was assessed by Mixed Methods Appraisal Tool (MMAT). Meta-analysis was performed for subgroups gait and alignment.ResultsOf the 362 studies retrieved, 24 were included. Study designs were cohorts with mixed methods (pre-post treatment, case-control and case-case) and three randomized controlled trials. The mean MMAT score was 75%, corresponding to low bias. In total 1178 patients and 197 controls were included. Results showed that pre-operative trunk motion was characterized by increased amplitudes in all three planes and altered alignment which did not all return to normal after TKA. Frontal plane motion and alignment recovered faster than the sagittal and transversal plane. Although pelvic tilt improved after surgery, sagittal imbalance (anteriorly shifted trunk position) was still present.SignificanceRecovery of trunk motion after TKA is time-, speed- and technique-dependent. The observed differences in trunk motion with the healthy controls persisted after TKA. This indicates that incorporating a full biomechanical chain approach, including trunk motion and gait-retraining exercises with a strong focus on postural alignment could improve functional mobility after TKA. Limited studies are available assessing trunk control and trunk motion during functional tasks besides walking which warrant further investigation.     

Does blood flow restriction training enhance clinical outcomes in knee osteoarthritis: A systematic review and meta-analysis

ObjectiveTo systematically review the efficacy of blood flow restriction training (BFRT) on individuals with knee osteoarthritis (OA).DesignSystematic review with meta-analysis.Literature searchEight electronic databases were searched by one researcher.Study selection criteriaRandomised clinical trials (RCTs) comparing BFRT to regular resistance training (RT) for knee OA.Data synthesisOne reviewer selected the eligible RCTs and exported the data. Two reviewers evaluated study quality using the PEDro scale. We performed meta-analysis where appropriate using a random-effects model. We rated the quality of evidence using GRADE.ResultsFive studies were eligible. The key outcomes analysed were pain, self-reported function, objective physical function, strength and muscle size. Across all comparisons, there was low to moderate quality evidence of no difference between BFRT and traditional RT.ConclusionThe limited available evidence does not suggest that BFRT enhances outcomes for people with knee OA. These findings do not support clinicians using BFRT in people with knee OA. Instead, evidence-based messages regarding exercise and education should remain the mainstay of rehabilitation. Additional studies should clarify whether some people with knee OA who cannot complete an adequate exercise programme due to pain, might still benefit from BFRT to facilitate less painful exercise.     

Patient function after a posterior stabilizing total knee arthroplasty: cam–post engagement and knee kinematics

Even though posterior substituting total knee arthroplasty has been widely used in surgery, how the cam–post mechanism (posterior substituting mechanism) affects knee joint kinematics and function in patients is not known. The objective of the present study was to investigate posterior femoral translation, internal tibial rotation, tibiofemoral contact, and cam–post engagement of total knee arthroplasty patients during in vivo weight-bearing flexion. Twenty-four knees with a PS TKA were investigated while performing a single leg weight-bearing lunge from full extension to maximum flexion as images were recorded using a dual fluoroscopic system. The in vivo knee position at each targeted flexion angle was reproduced using 3D TKA models and the fluoroscopic images. The kinematics of the knee was measured from the series of the total knee arthroplasty models. The cam–post engagement was determined when the surface model of the femoral cam overlapped with that of the tibial post. The mean maximum flexion angle for all the subjects was 112.5 ± 13.1°. The mean flexion angle where cam–post engagement was observed was 91.1 ± 10.9°. The femur moved anteriorly from 0° to 30° and posteriorly through the rest of the flexion range. The internal tibial rotation increased approximately 6° from full extension to 90° of flexion and decreased slightly with further flexion. Both the medial and lateral contact point moved posteriorly from 0° to 30°, remained relatively constant from 30° to 90°, and then moved further posterior from 90° to maximum flexion. The in vivo cam–post engagement corresponded to increased posterior translation and reduced internal tibial rotation at high flexion of the posterior substituting total knee arthroplasty. The initial cam–post engagement was also mildly correlated with the maximum flexion angle of the knee (R = 0.51, p = 0.019). A later cam–post engagement might indicate an environment conducive to greater flexion. If the factors that affect cam–post engagement timing can be established, proper manipulation of those factors may improve the function of the knee after posterior substituting total knee arthroplasty.     

帕瑞昔布钠对全膝全髋关节置换术后镇痛的疗效分析

目的 评价帕瑞昔布钠对全膝关节置换术(total knee arthroplasty,TKA)和全髋关节置换术(total hip arthroplasty,THA)术后的镇痛效果. 方法 本研究为前瞻性、随机、双盲研究,由同一组医师完成101例TKA患者和105例THA患者,根据镇痛方式分为三组:(1)术中静脉注射帕瑞昔布钠组;(2)术中关节局部注射帕瑞昔布钠组;(3)对照组.比较术后三组的视觉模拟疼痛评分(VAS)、关节活动度(ROM)、术后直腿抬高能力和恶心、呕吐等并发症的发生率. 结果 术中静脉注射帕瑞昔布钠组和术中关节局部注射帕瑞昔布钠组在术后各时段的VAS评分和术后24 h ROM及直腿抬高能力的差异无统计学意义(P＞0.05),但均明显优于对照组(P＜0.05).使用帕瑞昔布钠后恶心、呕吐等并发症的发生率没有显著增加. 结论 术中静脉注射和术中关节局部注射帕瑞昔布钠对TKA和THA术后的镇痛效果确切,有利于患者关节功能的迅速康复,且操作简便、实用,是TKA和THA镇痛的有效方法之一.     

全膝关节置换术中髌骨处理方法的研究

目的 比较全膝关节置换术(total knee arthroplasty,TKA)中保留髌骨下进行髌骨成形与髌骨置换的术后临床疗效,探讨膝关节置换中合适的髌骨处理方法.方法 回顾性分析2002年1月-2008年12月收治的共198例行TKA治疗的单纯骨关节炎患者,其中62例行髌骨置换术,136例行保留髌骨下髌骨成形术.术中对髌骨进行去除骨赘后进行成形,使之与原髌骨关节面比较相近.术后定期随访进行美国膝关节协会评分(KSS)、Bristol髌骨评分、患者满意度、膝关节活动度及分析术后膝前疼痛发生率,并复查X线片了解内置物情况.结果 共125例获得随访,其中置换组43例,成形组82例,随访时间36～80个月,平均51个月.两组患者术后较术前各项评分明显提高.术后1年随访时两组患者术后膝关节活动度、KSS总评分、髌骨评分、患者满意度差异无统计学意义,而KSS功能评分两组之间差异有统计学意义,成形组优于置换组.而术后膝前疼痛发生率两者有差异但无统计学意义.术后X线片示髌股匹配程度、术后膝前疼痛发生率及髌骨相关并发症发生率两组间差异无统计学意义.结论 髌骨成形术在TKA中髌骨不置换时能够使髌股关节达到良好匹配,术后膝前疼痛发生率低,中短期疗效与髌骨置换相当.     

Pre-operative diagnosis of infection in total knee arthroplasty: an algorithm

The aim of our study was to construct an algorithm for the pre-operative diagnosis of infection in total knee arthroplasty. We analyzed the currently used parameters in a consecutive series of 31 patients with failed implants. An outcome of at least 2 years was prospectively considered to validate our algorithm. Patient history, imaging, laboratory studies, histology, pre- and intra-operative cultures were considered. The optimal cutoffs of the inflammation tests for diagnosing infection were determined by constructing the receiver operating-characteristic curves. Sensitivity, specificity and accuracy of these tests as infection markers were determined. The combination of at least two tests with values higher than the cutoffs is reliable for predicting the infection. Scintigraphy, needle-aspirate cell count and culture can integrate the pre-operative evaluation. Doubtful cases can be clarified by microbiological and histological analyses. As a result an algorithm helpful to identify the cause of loosening has been developed. In our opinion, adherence to this algorithm could contribute to preoperatively define a rational surgical and antibiotic treatment strategy.     

Soft tissue balancing in varus total knee arthroplasty: an algorithmic approach

We present an algorithmic release approach to the varus knee, including a novel pie crust release technique of the superficial MCL, in 359 total knee arthroplasty patients and report the clinical and radiological outcome. Medio-lateral stability was evaluated as normal in 97% of group 0 (deep MCL), 95% of group 1 (pie crust superficial MCL) and 83% of group 2 (distal superficial MCL). The mean preoperative hip–knee angle was 174.0, 172.1, and 169.5 and was corrected postoperatively to 179.1, 179.2, and 177.6 for groups 0, 1, and 2, respectively. A satisfactory correction in the coronal plane was achieved in 82.9% of all-comers falling within the 180° ± 3° interval. An algorithmic release approach can be beneficial for soft tissue balancing. In all patients, the deep medial collateral ligament should be released and otseophytes removed. The novel pie crust technique of the superficial MCL is safe, efficient and reliable, provided a medial release of 6–8 mm or less is required. The release of the superficial MCL on the distal tibia is advocated in severe varus knees. Preoperative coronal alignment is an important predictor for the release technique, but should be combined with other parameters such as reducibility of the deformity and the obtained gap asymmetry.     

Stiffness of soft tissue complex in total knee arthroplasty

The significance of achievement of soft tissue balancing in total knee arthroplasty is well recognized. There are few reports dealing with soft tissue tension in total knee arthroplasty. It is expected that the soft tissue tension will affect post-operative results such as postoperative ROM and stability. The purpose of this study was to evaluate tension properties of soft tissue complex of osteoarthritic knee in total knee arthroplasty. Sixty osteoarthritic knees that underwent primary total knee arthroplasty were investigated with a balancer and torque driver specially developed and adapted for this study. We gradually opened the extension and flexion space and measured the force to open it. We created a force–displacement curve in each case. Inclination of the curve indicated stiffness. We examined the stiffness average of all cases every 10 N. The stiffness was 8.9 and 8.5 N/mm (extension, flexion) in soft tissue tension of 60 N and 26.6 and 21.4 N/mm in 180 N. The stiffness became larger with an increase of soft tissue tension, and the stiffness of extension is significantly larger than that of flexion in each tension except for 60 N. Tension properties of soft tissue complex reveal that soft tissue can be easily extended in low soft tissue tension, and hardly extended in high tension.     

The effect of running on knee joint cartilage: A systematic review and meta-analysis

ObjectiveAlthough running causes inevitable stress to the joints, data regarding its effect on the cartilage of the knee are conflicting. This systematic review and meta-analysis aimed to evaluate the effect of running on knee joint cartilage.MethodsPubMed, EMBASE, SportDiscus, and Cochrane Library databases were searched to identify randomized controlled trials (RCTs) and cohort studies. The outcome indicators were cartilage oligomeric matrix protein (COMP), cartilage volume and thickness, and T2.ResultsA total of two RCTs and 13 cohort studies were included. There was no significant difference in cartilage volume between the running and control groups (MD, −115.88 U/I; 95% CI, −320.03 to 88.27; p = 0.27). However, running would decrease cartilage thickness (MD, −0.09 mm; 95%CI, −0.18 to −0.01; p = 0.03) and T2 (MD, −2.78 ms; 95% CI, −4.12 to −1.45; p < 0.001). Subgroup analysis demonstrated that COMP immediately or at 0.5 h after running was significantly increased, but there were no significant changes at 1 h or 2 h.ConclusionsRunning has advantages in promoting nutrition penetrating into the cartilage as well as squeezing out the metabolic substance, such as water. Our study found that running had a short-term adverse effect on COMP and did not affect cartilage volume or thickness.     

Gender differences in knee abduction during weight-bearing activities: A systematic review and meta-analysis

BackgroundIncreased knee abduction during weight-bearing activities is suggested to be a contributing factor for the high knee injury risk reported in women. However, studies investigating gender difference in knee abduction are inconclusive.ObjectiveTo systematically review gender-differences in knee abduction during weight-bearing activities in individuals with or without knee injury.MethodsA systematic review and meta-analysis were conducted according to the PRISMA guidelines. A search in the databases Medline, CINAHL and EMBASE was performed until September 2015. Inclusion criteria were studies that reported (1) gender differences, (2) healthy individuals and/or those with anterior cruciate ligament (ACL) deficiency or reconstruction or patellofemoral pain PFP, and (3) knee abduction assessed with either motion analysis or visual observation during weight-bearing activity.ResultsFifty-eight articles met the inclusion criteria. Women with PFP had greater peak knee abduction compared to men (Std diff in mean; −1.34, 95%CI; −1.83 to −0.84). In healthy individuals, women performed weight-bearing tasks with greater knee abduction throughout the movement (initial contact, peak abduction, excursion) (Std diff in mean; −0.68 to −0.79, 95%CI; −1.04 to −0.37). In subgroup analyses by task, differences in knee abduction between genders were present for most tasks, including running, jump landings and cutting movements. There were too few studies in individuals with ACL injury to perform meta-analysis.ConclusionThe gender difference in knee abduction during weight-bearing activities should be considered in training programs aimed at preventing or treating knee injury.     

Performance-based physical function correlates with walking speed and distance at 3 months post unilateral total knee arthroplasty

BackgroundAfter total knee arthroplasty (TKA), walking speed and distance are main concerns of patients.Research questionWhich physical functions affect walking speed and distance after TKA?MethodsCross-sectional data from 149 patients who underwent unilateral primary TKA and completed performance-based physical function tests. Instrumental gait evaluation for spatiotemporal parameters, isometric knee extensor and flexor strength of both knees, 6-minute walk test (6MWT), timed up-and-go (TUG) test, timed stair climbing test (SCT), and knee flexion and extension range of motion (ROM) of surgical knee were examined. Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and EuroQol five dimensions (EQ-5D) questionnaires were also performed.ResultsUnivariate analyses revealed that post-operative walking speed showed significant positive correlations with cadence, stride length, propulsion index of surgical and non-surgical knee, peak torque (PT) of the extensor of surgical and non-surgical knee and flexor of surgical and non-surgical knee, 6MWT, EQ-5D, and significant negative correlations with gait cycle duration, TUG, SCT-ascent and descent, and WOMAC-pain scores. Post-operative walking distance had significant positive correlations with walking speed, cadence, stride length, swing phase duration, propulsion index of surgical and non-surgical knee, PT of the extensor of surgical and non-surgical knee, EQ-5D, and significant negative correlation with gait cycle duration, double support duration, TUG, SCT-ascent and descent. In the multivariate linear regression analyses, TUG, cadence, stride length and propulsion index of non-surgical knee were factor correlated with post-operative walking speed. The SCT-ascent and descent, TUG and propulsion index of surgical knee were factor correlated with post-operative walking distance.SignificancePhysical performance factors correlated with walking speed and distance at 3 months after surgery. Based on these observations, rehabilitation of bilateral muscle strength and functional mobility would be important for functional recovery after unilateral TKA.     

Revision after early aseptic failures in primary total knee arthroplasty

The purpose of this study was to evaluate cases of early aseptic failures presented during the first 5-year follow-up in a group of 981 primary total knee arthroplasty (primary TKA). Predisposing factors as well causes of failures and postoperative complications in different groups of aseptic failures were re-assessed and compared to a control group. A retrospective and cohort study compared one group of 944 primary TKA without surgical revision (890 patients) (Group A) with 22 primary TKA (22 patients) (Group B) that had revision TKA secondary to aseptic failure during the first five years follow-up. The cases of isolated patellar button replacement (n = 8) and infection (n = 7) were not considered in this study. All patients underwent a systematic assessment that included clinical and radiographic examinations, and IKS scores. Aseptic failure was more prevalent at the first 2-year follow-up (63%). TKA loosening (n = 11) and undiagnosed pain (n = 7) were considered the most frequent modes of failures, and laxity (n = 1) was a very rare early cause of failure. The aseptic failure group was characterized as average 5 years younger with a greater number of previous knee surgeries, lower IKS scores improvement, and more postoperative pain compared to control group, despite the fact that the aseptic failure group showed a prevalence of cases during the first 2-year follow-up. Inside this group, the undiagnosed pain group had lower improvement of IKS scores, a remarkable prevalence in prior surgical procedure (71%) and a minor mean interval between primary and revision TKA (11.6 months).     

How proprioception changes before and after total knee arthroplasty: A systematic review

BackgroundProprioception is one of the most significant factors in balance, joint stability, graceful movement, coordination, and injury prevention. It involves a wide set of receptors located within joints, muscles, and tendons. Given the neurophysiological processes involved in proprioception response are multiple and complex, there is not one single method to measure it. Particularly, proprioception of the knee joint, whether it is healthy, affected by osteoarthritis, or after replacement, is the most investigated by in literature.Research questionThis review addresses the analysis of proprioception in the knee joint before and after total knee arthroplasty (TKA). The aim is to obtain an overview of the proprioceptive skills in subjects who suffered from osteoarthritis and were subjected to knee replacement, evaluating changes in proprioception before and after the surgery.MethodsThe research was conducted within four databases: Web of Science®, PubMed Central®, Cochrane®, and PEDro®, between January 2008 and February 2018. Accurate exclusion criteria and selection strategy were applied to screen the 170 articles found.ResultsUltimately, 13 papers were fully evaluated and included in this review, divided into two classes: i) works directly measuring proprioception, ii) studies indirectly evaluating proprioception. Contrasting results emerged from the analysis, and no consensus was found in the literature about the improvement or worsening in proprioception before and after TKA.SignificanceSince currently there is high variability in methods, protocol and parameters used to evaluate knee proprioception, further investigations based on a consistent dataset, a well-defined protocol, measurable outcomes, timeline follow-ups, and rehabilitation programs should be performed in order to obtain reliable results on the effects of TKA on knee proprioception and balance.     

Effects of total knee arthroplasty for primary knee osteoarthritis on postural balance: A systematic review

BackgroundKnee osteoarthritis is often related to physical function impairment. Although total knee arthroplasty is considered effective for advanced cases of knee osteoarthritis, its effects on postural balance is a topic of debate.Research questionWhat are the effects of total knee arthroplasty for primary knee osteoarthritis on postural balance compared to preoperative status and/or to healthy controls?.MethodsLongitudinal studies (with more than 1-month follow-up) assessing postural balance measures (either clinical-based such as balance scales or laboratory-based such as postural sway) were considered eligible and selected in a 2-phase process. Six main electronic databases were searched, complemented by 3 grey literature sources. The risk of bias was evaluated using the Joanna Briggs Institute Critical Appraisal Tools.ResultsA total of 19 studies were included for qualitative synthesis, of which 14 had low and 5 had a moderate risk of bias. The follow-up period ranged from 1–24 months. Most studies (n = 11) presented comparisons to preoperative status only. From these, 7 studies reported relevant improvements in postural balance, 2 reported partial improvements, and 2 no improvements. The remaining studies (n = 8) presented comparisons to healthy controls and, although improvements following total knee arthroplasty were consistently observed, only one study reported postural balance measures comparable to that of controls.ConclusionsThe majority of studies reported relevant improvements (especially in clinical-based measures) compared to preoperative evaluations, although inconsistencies were found possibly due to variability in studies' populations, assessment tools, and follow-up times. Despite this, persistent deficits in postural balance were commonly observed when compared to healthy controls.SignificanceThis evidence synthesis could better inform clinicians and researchers about the therapeutic effects and limitations of total knee arthroplasty concerning postural balance. Standardization of assessment tools is recommended to strengthen the certainty of cumulative evidence.     

人工全膝关节置换术股骨截骨方法改良及效果

目的对人工全膝关节置换术股骨截骨方法进行改良,通过截骨厚度的测量和临床随访对改良截骨方法的手术效果进行评估。方法改良股骨截骨模板,股骨后髁截骨厚度增加3mm。对81例人工全膝关节置换术中的各向截骨厚度进行测量,分为膝内翻和膝外翻两组,对截骨厚度和假体厚度进行比较分析。术后平均随访27.1个月。结果全组患者屈膝间隙和伸膝间隙平均截骨厚度均小于假体厚度。膝内翻和膝外翻组间除股骨后髁内侧截骨厚度外,各项测量值间差异均存在显著性意义(P<0.01)。膝内翻组内侧屈伸膝间隙截骨厚度和假体厚度差异最大;膝外翻组,外侧屈伸膝间隙截骨厚度和假体厚度差异最大。膝内翻组,外侧屈膝间隙存在过度截骨(0.57mm);膝外翻组,内侧屈膝间隙存在过度截骨(0.92mm)。术后关节活动度良好,仅7%的患者存在轻度屈膝不稳,无中重度不稳。结论对股骨截骨模板的改良是可行的,股骨后髁截骨厚度增加3mm不会出现过度截骨和屈膝不稳的情况。     

Orthopaedic management of knee joint impairment in cerebral palsy: A systematic review and meta-analysis

BackgroundThe optimal management of impaired knee joint function in patients with cerebral palsy (CP) remains a significant and ongoing challenge in paediatric orthopaedic surgery.Research questionWhat are the clinical and functional outcomes after operative and non-operative orthopaedic interventions for knee joint impairment in patients with CP?MethodsThis systematic review and meta-analysis of orthopaedic interventions for the management of knee joint impairment in paediatric CP patients evaluated study-level data in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. We performed searches of the following electronic databases from their dates of inception to November 2019: Medline (Ovid), Embase (Ovid) and Pubmed. We extracted mean differences in pre-operative and post-operative measurements for the following outcomes: minimum knee flexion in stance; knee flexion at initial contact; maximum knee flexion in swing; range of motion; popliteal angle; fixed flexion deformity angle; and mean pelvic tilt.ResultsSixty-nine retrospective cohort studies, prospective cohort studies and RCTs comprising 2991 patients were included with 4578 knees analysed. Included studies were of sufficient quality as assessed by the MOOSE checklist. Operative interventions showed significant improvement in knee flexion at initial contact, knee flexion in stance, range of motion, popliteal angle and fixed flexion deformity which were comparable when subgrouped according to operative technique. In contrast, non-operative techniques and botulinum toxin injection did not confer significant improvements. Operative interventions for knee joint impairment led to increased mean pelvic tilt and reduced maximum knee flexion in swing.SignificanceThis review provides strong evidence that operative interventions for the management of knee joint impairment in cerebral palsy patients improve knee kinematics and clinical examination findings.     

Clinical and functional results after the rehabilitation period in minimally-invasive unicondylar knee arthroplasty patients

The objective of the present study was to analyze the clinical and functional outcome after minimally-invasive implantation of a Repicci-type unicompartmental sledge prosthesis . In 29 patients with primary unicompartmental knee osteoarthritis, 29 replacements of the medial compartment and four of the lateral compartment were performed using the minimally-invasive technique with the metal-backed and the all-polyethylene versions of the Repicci sledge prosthesis. Electromyography (EMG) of standardized locations was measured with the MyoSystem 2000 and analyzed with Myoresearch software. Gait analysis was performed with a six-camera motion analysis system and force platforms. Established clinical and quality of life (SF-36) scores were used to compare patients with 11 healthy age-matched individuals. The Repicci sledge prosthesis led postoperatively to functional results that were in the range of healthy joints, and superior to sledge prostheses of a different design. Gait and balance parameters were comparable to the control group, whilst electromyographically lower amplitudes were found in the patients than the controls and in the operated legs as compared to the non-operated legs. Many parameters of quality of life and activity were comparable to age-matched healthy individuals, and quality of life was superior to total knee replacement. When implanted using a minimally-invasive technique and with suitable patient selection, the Repicci sledge led to functional results comparable to those of healthy joints and gait parameters comparable to those of healthy individuals. The level of evidence is Level III, retrospective cohort study.     

Increased knee flexion and varus moments during gait with high-heeled shoes: A systematic review and meta-analysis

BackgroundHigh-heeled shoes have been thought to alter lower extremity joint mechanics during gait, however its effects on the knee remain unclear.Research questionThis systematic review and meta-analysis aimed to determine the effects of high-heeled shoes on the sagittal- and frontal-plane knee kinetics/kinematics during gait.Methods1449 studies from 6 databases were screened for the following criteria: 1) healthy adult females, 2) knee joint kinematics/kinetics reported for the early stance phase during gait under varying shoe heel heights (including barefoot). Excluded studies included those mixing different shoe styles in addition to altering the heel heights. A total of 14 studies (203 subjects) met the selection criteria, resulting in 51 and 21 Cohen’s d effect sizes (ESs) comparing the differences in knee sagittal- (flexion) and frontal-plane (varus) moment/angle, respectively, between shoes with higher heels and shoes with lower heels/barefoot.ResultsMeta-analyses yielded a significant medium-to-large effect of higher heels compared to lower heels on increasing knee flexion moment (overall ES = 0.83; P < 0.01), flexion angle (overall ES=0.46; P < 0.01), and varus moment (overall ES=0.52; P < 0.01) during the early stance phase of gait. The results of meta-regressions used to explore factors explaining the heterogeneity among study ESs revealed that a greater ES in the knee flexion moment was associated with an elevated heel height of the high-heeled shoes (P = 0.02) and greater body mass of the individuals (P = 0.012). A greater ES in the knee varus moment during high-heeled gait was associated with a greater body height (P = 0.003) and mass (P = 0.006).SignificanceGiven the association between increased knee flexion/varus moments and risk of developing knee osteoarthritis (OA), women who wear high-heel shoes frequently and for a long period may be more susceptible to knee OA. Preventive treatments, such as lower extremity muscle strengthening, may help improve shock absorption to decrease knee loading in high-heel users.     

One-stage versus two-stage exchange arthroplasty for infected total knee arthroplasty: a systematic review

Purpose

Infection complicating total knee arthroplasty (TKA) has serious implications. Traditionally the debate on whether one- or two-stage exchange arthroplasty is the optimum management of infected TKA has favoured two-stage procedures; however, a paradigm shift in opinion is emerging. This study aimed to establish whether current evidence supports one-stage revision for managing infected TKA based on reinfection rates and functional outcomes post-surgery.

Methods

MEDLINE/PubMed and CENTRAL databases were reviewed for studies that compared one- and two-stage exchange arthroplasty TKA in more than ten patients with a minimum 2-year follow-up.

Results

From an initial sample of 796, five cohort studies with a total of 231 patients (46 single-stage/185 two-stage; median patient age 66 years, range 61–71 years) met inclusion criteria. Overall, there were no significant differences in risk of reinfection following one- or two-stage exchange arthroplasty (OR ?0.06, 95 % confidence interval ?0.13, 0.01). Subgroup analysis revealed that in studies published since 2000, one-stage procedures have a significantly lower reinfection rate. One study investigated functional outcomes and reported that one-stage surgery was associated with superior functional outcomes. Scarcity of data, inconsistent study designs, surgical technique and antibiotic regime disparities limit recommendations that can be made.

Conclusion

Recent studies suggest one-stage exchange arthroplasty may provide superior outcomes, including lower reinfection rates and superior function, in select patients. Clinically, for some patients, one-stage exchange arthroplasty may represent optimum treatment; however, patient selection criteria and key components of surgical and post-operative anti-microbial management remain to be defined.

Level of evidence

III.