The safety and feasibility of minimal invasive plate osteosynthesis (MIPO) of the posterior aspect of the humerus: A cadaveric study

The aim of this study was to determine the feasibility of applying MIPO of the humerus via the posterior approach and to observe the tension of the radial nerve in different elbow positions. Two separate incisions were made on the posterior aspect of the humerus in ten fresh cadavers (20 humeri). The radial nerve was identified at the proximal incision and the distances through which the nerve could be elevated from the bone with the elbow in flexion and extension were measured. A 10‐hole extra‐articular distal humeral locking compression plate was inserted and fixed through the submuscular tunnel. The tunnel was then explored to identify any entrapment of the radial nerve and to observe the anatomical relationship of the radial nerve to the plate and bone. There was no entrapment of the radial nerve or its branches. The distances through which the radial nerve could be elevated were greater with the elbow in extension than in flexion (P < 0.01). The radial nerve crossed the medial and lateral borders of the posterior surface of the humerus at 80.1–132 mm (average 104.7 mm) and 116.6–175.5 mm (average 142.7 mm) of its total length, respectively. The axillary nerve was located at 38.7–61.7 mm (average 47.9 mm) of total humeral length. MIPO of the humerus using the posterior approach is an alternative option for treating distal humeral shaft fracture. The risk of radial nerve injury can be minimized by careful dissection in the proximal incision. Clin. Anat. 32:176–182, 2019. © 2018 Wiley Periodicals, Inc.     

A novel angle on helical blade placement in trochanteric fractures – The axis-blade angle

IntroductionFor trochanteric fractures, helical blade placement is crucial to the prognosis of operations. Existing measurement methods used for blade placement include the Cleveland zone, the tip-apex distance (TAD), the calcar-referenced tip-apex distance (CalTAD), and the Parker's ratio. These methods all lack a direct view on blade direction. The current study proposed the axis-blade angle (ABA) to solve direction problem and investigated its clinical applicability.MethodsA retrospective study collected 156 patients between May 2014 and February 2018. The occurrence of mechanical complications was analyzed in relation to age, gender, fracture side, American Society of Anesthesiologists classification, fracture classification, reduction quality, bone quality, the Cleveland zone, the Parker's ratio, the TAD, the CalTAD, and the ABA.Results119 patients, including 25 with mechanical complications, were suitable for full analysis. In the univariate analysis, the Cleveland zone, reduction quality, the TAD, the CalTAD and the ABA were statistically associated with mechanical complications. In the multivariate analysis, reduction quality (p = 0.008) and the ABA (p < 0.001; adjusted OR 0.86;95% CI 0.77 to 0.96) showed significant results, which indicated that reduction quality and the ABA were two independent influencing factors for mechanical complications. Calculation of the receiver operating characteristic (ROC) curve indicated that the ABA was a reliable predictor of mechanical complications at the cut-off of −10°.ConclusionsThe ABA provides instruction for the intraoperative adjustment of guide wire direction. Placing the helical blade with an ABA > −10° can effectively reduce the risk of mechanical complications.     

锁骨钩钢板内固定术后钢板钩与肩峰匹配性影像学研究

目的通过测量锁骨钩钢板内固定术后患者影像学资料，分析发生肩峰骨侵蚀的原因是否与钢板钩-肩峰匹配度相关。 方法回顾性分析2015年8月1日至2018年8月31日期间在上海市浦东医院骨科就诊的210例患者的影像学资料，210例患者均因肩锁关节脱位或锁骨远端骨折行锁骨钩钢板内固定治疗，其中男110例、女100例；年龄24~76岁，平均（44.60±8.75）岁；肩锁关节脱位70例，锁骨远端骨折140例。测量术后及终末随访患者肩锁关节正位X线片相关数据，按锁骨钩钢板术后是否发生肩峰骨侵蚀，将纳入患者分为3组：无骨侵蚀组（A组）、伴钢板钩移位骨侵蚀组（B组）、不伴移位的骨侵蚀组（C组），分别测量钢板钩-肩峰的匹配度（β），统计分析术后发生肩峰骨侵蚀与钢板钩-肩峰匹配度之间的关系。 结果纳入研究的210例患者术后随访24~64周，平均（32.0±6.5）周。A组患者115例，B组患者54例，C组患者41例。A组匹配度β（3.72±0.48）mm与B组β¹（6.91±0.84）mm比较差异有统计学意义（P<0.05）；A组匹配度β（3.72±0.48）mm与C组β²（5.88±0.65）mm比较差异有统计学意义（P<0.05）；B组匹配度β¹（6.91±0.84）mm与C组β²（5.88±0.65）mm比较差异有统计学意义（P<0.05）。 结论锁骨钩钢板内固定术后是否发生肩峰骨侵蚀与钢板钩-肩峰匹配度β存在明显相关性，钢板钩与肩峰之间的匹配度越好，β值越小，发生肩峰骨侵蚀的可能性更小。     

Does use of a quadrilateral surface plate improve outcome in elderly acetabular fractures?

BackgroundAcetabular fractures in the elderly frequently involve segmental quadrilateral plate injury, yet no consensus exists on how to best control the femoral head medial displacement. Quadrilateral surface plates (QSP) were developed to help buttress these challenging fractures. The study aims to 1) Determine the prevalence of segmental quadrilateral plate fractures (SQPF) in elderly patients; and 2) Assess if utilization of a QSP is associated with improved acetabulum fracture reduction and outcome.MethodsThis was a retrospective study conducted at a level-1 trauma centre. . All patients over 60-years that sustained an acetabular fracture between 2007 and 2019 were reviewed. Pre-operative pelvic radiographs and CT imaging were reviewed for 96 patients, to assess for SQPF. From the 96 patients reviewed, over one third of patients (n = 40, 41.6%) sustained a SQPF. Patients that had an acute-THA (n = 7) were excluded as were patients that underwent an ORIF but did not have a QSP or an anterior column buttress plate (n = 3). The remaining 30 formed the study’s cohort. We assessed the ability to achieve and maintain reduction in this elderly population, and compared outcomes using traditional anterior column buttress plates (ilioingual or intra-pelvic approach) versus an intra-pelvic pre-contoured buttress suprapectineal plate (QSP). Outcome measures included: fracture reduction using the Matta classification (desirable: anatomical/imperfect and poor), re-operations, conversion to THA and Oxford Hip Score (OHS) (for the preserved hips).ResultsTen patients had an ORIF with utilization of a QSP (QSP-group), and 20 had an ORIF but did not have the QSP (non-QSP-group). There was no difference in patient demographics between groups. Fracture patterns were also similar (p = 0.6). Postoperative fracture reduction was desirable (anatomical/imperfect) in 17 patients and poor in 13. Improved ability to achieve a desirable reduction was seen in the QSP-group (p = 0.02). Conversion to THA was significantly lower in patients that had a desirable fracture reduction (appropriate: 3/17; poor: 7/13). No patients in the QSP-group have required a THA to-date, compared to 10/20 patients in the non-QSP-group (p = 0.01). The mean time to THA was 1.6 ± 2.1 year. There was no difference in OHS between the two groups (34.4 ± 10.3).ConclusionElderly acetabulum fractures have a high incidence (approaching 40%) of segmental QPF. Desirable (anatomical/imperfect) fracture reduction was associated with improved outcome. The use of a QSP was associated with improved ability to achieve an appropriate reduction. A QSP should be considered as they are both reliable and reproducible with a significantly improved fracture reduction and lower conversion to THA.     

Digital bathroom scales with open source software provide valid dynamic ground reaction force data for assessment and biofeedback

BackgroundMeasuring dynamic vertical ground reaction force allows for assessment of important clinical and physical capacity factors such as weight bearing asymmetry, force distribution, and rate of force development. However, current technologies for accurately assessing ground reaction force are typically expensive.Research QuestionThe aim of this study was to examine the validity and reliability of obtaining static and dynamic ground reaction force data from low-cost modified digital bathroom scales.MethodsFour modified bathroom scales, two units each of two different brands, were examined. Repeated mechanical loading trials were performed with known loads ranging from 0.01 to 65 kg, with acquired data compared against the known loading to calculate accuracy, hysteresis, and non-linearity. Dynamic trials consisting of 5 times sit-to-stand and weight-shifting were performed by 32 adults. Absolute and relative agreement intraclass correlation coefficient, and Pearson’s and Spearman’s correlations were performed to determine validity and reliability for the mechanical tests. Bland-Altmann plots were created for each comparison. Mean absolute error (MAE) and unbiased cross-correlation were performed on the dynamic data, comparing the calibrated data to the known values from a Bertec force platform.ResultsHysteresis and non-linearity were excellent (<0.2 % full-scale), and mechanical test results showed excellent reliability and validity. Cross-correlation results for the dynamic data were excellent, however MAE for the more rapid sit-to-stand task was higher than the slower weight-shifting test. This may have been due to the low default sampling rate for the lowest noise setting of the HX711 amplifier (10 Hz).SignificanceIn summary, our results suggest that digital bathroom scales can be easily and inexpensively modified to obtain accurate vertical ground reaction force data, with sensitivity to detect changes of as little as 0.01 kg.     

基于荧光定量PCR技术的当归不同炮制品中大肠埃希菌数量测定方法开发及比较研究

目的对当归不同炮制品中大肠埃希菌变化进行定量分析。方法建立荧光定量PCR方法,对当归不同炮制品、不同产地、不同收集企业、不同储藏时间的大肠埃希菌进行定量分析。结果不同炮制品中大肠埃希菌数量变化为生当归土炒当归酒当归;在不同产地的当归中以甘肃岷县地区所含的大肠埃希菌的数量最少;与零售企业相比,生产销售企业的当归和酒当归中大肠埃希菌的数量较少;不同储藏时间对当归和酒当归中大肠埃希菌数量有一定影响,随储藏时间的增加,大肠埃希菌的数量也在增加。对部分代表性样品进行平板计数法与荧光定量PCR法比较时发现,平板计数法结果多呈阴性,荧光定量PCR结果均呈阳性。结论所建立的荧光定量PCR法特异性、灵敏度、可靠性以及报告周期均优于平板计数法,可为当归不同炮制品中大肠埃希菌的快速、准确定量检测提供有效手段。