Linkage guide for rotational alignment during total knee arthroplasty

A linkage guide was devised for use in conjunction with knee arthroplasty instruments to achieve proper component rotation. The femoral component was rotationally aligned to the surgical epicondylar axis using one guide. The other guides were used after all bone surfaces were cut and soft tissue balancing was completed. A Kirschner wire was guided into the proximal tibial aspect parallel to the sagittal plane of the femoral component with the patella in its normal position and the knee in full extension. The wire was used as a reference to determine tibial component rotation. The relative rotational alignment of 21 knees in 19 patients who had undergone cruciate-retaining total knee arthroplasty utilizing this guide was assessed using the modified Eckhoff method. The results of radiographic analysis were compared with those in a control group of 25 knees where the guide was not employed. The external rotation of the femoral component relative to the tibial component was 1.3° ± 2.0° (mean ± SD) in the guided group and 1.1° ± 4.4° in the control group. The relative rotational angle was significantly more consistent using the guide. Implant malrotation can be reduced using our technique.     

个性化截骨工具辅助下人工全膝关节置换与传统人工全膝关节置换手术精确度及临床疗效比较

目的比较3D打印个性化截骨工具辅助(patient-specific instrumentation,PSI)下人工全膝关节置换术(total knee arthroplasty,TKA)与传统TKA的手术精确度和临床疗效。方法自2017年9月至2018年12月,将40例拟接受初次膝关节置换患者随机分为2组,每组均为20人。一组应用个性化截骨工具辅助TKA手术(PSI组),另一组接受传统TKA(对照组)。比较两组患者的冠状面下肢机械轴线、手术时间、术中出血量、术后引流量以及HSS评分。结果对照组和PSI组的手术时间分别为(103.3±18.7) min和(91.3±15.7) min;术中出血量分别为(372.0±53.0)mL和(332.8±47.0)mL;术后引流量分别为(378.8±97.2)mL和(315.0±89.0)mL。两组手术时间、术中出血量、术后引流量比较差异均有统计学意义(P0.05)。对照组和PSI组术后2周HSS评分分别为(89.3±2.8)分和(88.7±2.9)分,两组比较差异无统计学意义(P0.05)。对照组和PSI组术后全下肢力线差值分别为(1.9±1.1)°和(1.2±1.0)°,冠状面股骨假体角度(frontal femoral component angle,FFC)差值分别为(2.1±1.1)°和(1.1±0.9)°,两组比较差异有统计学意义(P0.05)。冠状面胫骨假体角度(frontal tibia component angle,FTC)差值分别为(1.3±0.8)°和(1.4±0.8)°,两组比较差异无统计学意义(P0.05)。结论PSI辅助TKA较传统TKA手术时间更短、术中出血量更少,并且术后冠状面全下肢力线及股骨力线的改善优于传统TKA手术。     

A short-term radiological and clinical comparison between the bi-cruciate and cruciate retaining total knee arthroplasty A retrospective case controlled study

PurposeThe aim of this study was to provide a short term comparison in radiological and clinical outcome between Bi-Cruciate Retaining (BCR)- and Cruciate Retaining (CR) Total Knee Arthroplasty (TKA).MethodsThe cohort consists of 122 patients undergoing a TKA with PSI, equally distributed over the BCR- and CR-TKA group. Perioperative conditions were observed and radiological images were analysed pre-, 6-weeks, and 1-year postoperative to quantify alignment differences between BCR- and CR-TKA. Preoperatively predicted templates were compared with the implanted size to determine predictive value. In addition mean range of motion and revision rates were determined in both groups.ResultsNo significant difference was observed in amount of outliers in component alignment between BCR- and CR-TKA. Outliers of the Hip-Knee-Ankle-Axis (HKA-axis) occurred significantly more frequent (P = 0.009) in the BCR-group (37.7%) compared to CR-TKA (18.0%). No clinically relevant differences regarding the predictive sizing of implant components was obtained. No significant differences were observed in revision rates (P = 1.000) and ROM (p = 0.425) between the BCR-groep and CR-group at 2-years FU.ConclusionThis study illustrates that although the HKA-axis was not fully restored, bi-cruciate retaining surgical technique for BCR-TKA is safe and effective with comparable radiological and clinical outcome as CR TKA. Randomized controlled trials with longer follow up on the HKA-axis alignment and clinical parameters are needed to confirm the presented results and should focus on possible cut off values concerning leg axis in order to define in what patients a BCR-TKA can safely be used.Level of evidence IVRetrospective Case Controlled Study.     

DNA Commission of the International Society for Forensic Genetics: Revised and extended guidelines for mitochondrial DNA typing

The DNA Commission of the International Society of Forensic Genetics (ISFG) regularly publishes guidelines and recommendations concerning the application of DNA polymorphisms to the question of human identification. Previous recommendations published in 2000 addressed the analysis and interpretation of mitochondrial DNA (mtDNA) in forensic casework. While the foundations set forth in the earlier recommendations still apply, new approaches to the quality control, alignment and nomenclature of mitochondrial sequences, as well as the establishment of mtDNA reference population databases, have been developed. Here, we describe these developments and discuss their application to both mtDNA casework and mtDNA reference population databasing applications. While the generation of mtDNA for forensic casework has always been guided by specific standards, it is now well-established that data of the same quality are required for the mtDNA reference population data used to assess the statistical weight of the evidence. As a result, we introduce guidelines regarding sequence generation, as well as quality control measures based on the known worldwide mtDNA phylogeny, that can be applied to ensure the highest quality population data possible. For both casework and reference population databasing applications, the alignment and nomenclature of haplotypes is revised here and the phylogenetic alignment proffered as acceptable standard. In addition, the interpretation of heteroplasmy in the forensic context is updated, and the utility of alignment-free database searches for unbiased probability estimates is highlighted. Finally, we discuss statistical issues and define minimal standards for mtDNA database searches.     

减重下力线矫正训练对脑瘫患儿骨盆前倾的影响

目的 观察减重下力线矫正训练（WBAT）对矫正脑瘫患儿骨盆前倾的疗效。 方法 选取站立位骨盆前倾的脑瘫患儿27例,按随机数字表法分为WBAT组、站立训练组和肌力训练组,每组患儿9例。3组均给予常规康复治疗,WBAT组在此基础上增加自行设计的WBAT训练,肌力训练组增加骨盆稳定及下肢抗重力肌群抗阻训练,站立训练组增加站立板辅助站立训练,以上3种治疗均每次20 min,每周5次,连续治疗4周。于治疗前和治疗后（治疗4周后）分别对3组患儿的骨盆倾斜角（ASIS-PSIS）、躯干倾斜角(A-P)及1 min步行距离进行评估。 结果 治疗后,WBAT组的ASIS-PSIS和A-P分别为（18.61±3.13）°和（23.31±3.81）°,站立组的A-P为（24.48±4.33）°,分别与组内治疗前比较,差异均有统计学意义（P<0.05）;且WBAT组治疗后的ASIS-PSIS与肌力训练组和站立训练组治疗后比较,差异均有统计学意义（P<0.05）。治疗后,WBAT训练组的1 min步行距离为（26.81±12.61）m,肌力训练组的1 min步行距离为（21.07±8.45）m,分别与组内治疗前比较,差异均有统计学差异（P<0.05）;且WBAT组治疗后的1 min步行距离与肌力训练组和站立训练组治疗后比较,差异均有统计学意义（P<0.05）。 结论 WBAT训练可显著改善骨盆前倾脑瘫患儿的ASIS-PSIS、A-P以及1 min步行距离,且其疗效优于传统的肌力训练和站立训练。     

Impact of joint line orientation on clinical outcomes in bilateral Oxford mobile-bearing unicompartmental knee arthroplasty

BackgroundJoint line orientation angle (JLOA) is the angle between the knee joint line and the floor. It has been reported to be related to postoperative outcome after TKA. Regarding unicompartmental knee arthroplasty (UKA), although it can be horizontal after UKA because it is a resurfacing surgery, there are few reports about the JLOA after UKA and its impact on clinical outcomes.PurposeThe purpose of this study was to reveal the relationship between JLOA and clinical outcome after UKA.MethodsThis study included 106 knees in 53 consecutive patients with osteoarthritis who underwent simultaneous bilateral mobile-bearing UKA. Their pre- and postoperative JLOAs were measured by full-leg-length standing coronal radiographs. We also evaluated the tibial component height (TCH) as the factor which we assumed could influence JLOA. We analyzed the patients’ JLOAs, TCHs and clinical outcomes.ResultsPre- and postoperative JLOA were 0.4 ± 2.4° and 2.7 ± 2.6°, respectively. The JLOA significantly tilted medially (P < 0.0001). The JLOA significantly negatively correlated with the improvement of the clinical outcomes (Oxford Knee Score (OKS): r = 0.40, P < 0.0001, Knee Society Knee Score (KSKS): r = 0.25, P < 0.01, Knee Society Function Score (KSFS): r = 0.22, P = 0.02). The TCH showed a positive correlation with postoperative JLOA and with the postoperative JLOA change (r = 0.45, P < 0.001; r = 0.25, P < 0.01, respectively).ConclusionThe JLOA significantly tilted medially after UKA. An excessive medial tilt of the JLOA was associated with poorer postoperative outcomes of UKA. It is therefore recommended to keep the JLOA horizontal and to avoid a lower tibial cut.     

The Relationship between Neck Pain and Cervical Alignment in Young Female Nursing Staff

Objective

Degenerative changes in the cervical spine are commonly accompanied by cervical kyphosis which can cause neck pain. This study examined the relationship between neck pain and cervical alignment.

Methods

A total of 323 female nursing staff from our hospital were enrolled. Sagittal radiographs of the cervical spine, Body Mass Index (BMI), Visual Analogue Scale (VAS) measures of neck and arm pain, Neck Disability Index (NDI) and the Short Form (36) Health Survey (SF-36 scores) were obtained and reviewed retrospectively. Global lordosis (GL) of the cervical spine was measured on radiograph images. Correlations between GL and questionnaire scores were investigated using the following three methods : 1) correlation between GL and questionnaire scores among the entire sample; 2) subgroup analysis of patients with "kyphosis (KYP) : GL scores<0" vs. those with "lordosis (LOR) : GL scores>0" on questionnaire measures; and 3) subgroup analysis of patients with pain vs. those without pain, on GL and questionnaire measures.

Results

There was no significant correlation between GL and any questionnaire measure. There was a significant difference between the mean GLs of the KYP and LOR groups, but there were no group differences in BMI, age or any questionnaire measures. There was no difference between the pain (n=92) and pain-free (n=231) groups in age, BMI or GL, but there were differences in neck, and arm pain, and physical function and NDI scores.

Conclusions

Our data suggest that kyphotic deformity was not associated with neck pain.