Alternative Methods for Measuring Scapular Muscles Protraction and Retraction Maximal Isometric Forces

Background

The importance of the scapular stabilizing muscles has led to an increased interest in quantitative measurements of their strength. Few studies have measured isometric or concentric isokinetic forces. Additionally, limited reports exist on the reliability of objective measures for testing scapular protraction and retraction muscle strength or scapular testing that does not involve the glenohumeral joint.

Objective

To determine the reliability of four new methods of measuring the maximal isometric strength of key scapular stabilizing muscles for the actions of protraction and retraction, both with and without the involvement of the glenohumeral (GH) joint.

Methods

The Isobex® stationary tension dynamometer was used to measure the maximal isometric force (kg) on thirty healthy females (ages 22–26 years). Three measures were taken for each method that was sequentially randomized for three separate testing sessions on three nonconsecutive days.

Results

Intraclass correlations (ICC2,3) for intrasession reliability and (ICC3,3) for intersession reliability ranged from 0.95 to 0.98, and 0.94 to 0.96 respectively. The standard errors of measurement (95% confidence interval [CI]) were narrow. Scatter grams for both protraction and retraction testing methods demonstrated a significant relationship, 0.92 for protraction (95% CI 0.83 to 0.96) and 0.93 for retraction (95% CI 0.87 to 0.97). Bland-Altman plots indicated good agreement between the two methods for measuring protraction strength but a weaker agreement for the two methods measuring retraction strength.

Discussion/Conclusion

The four new methods assessed in this study indicate reliable options for measuring scapular protraction or retraction isometric strength with or without involving the GH joint for young healthy females.     

Acute surgical unit safely reduces unnecessary after-hours cholecystectomy

Introduction

The acute surgical model has been trialled in several institutions with mixed results. The aim of this study was to determine whether the acute surgical model provides better outcomes for patients with acute biliary presentation, compared with the traditional emergency surgery model of care.

Methods

A retrospective review was carried out of patients who were admitted for management of acute biliary presentation, before and after the establishment of an acute surgical unit (ASU). Outcomes measured were time to operation, operating time, after-hours operation (6pm – 8am), length of stay and surgical complications.

Results

A total of 342 patients presented with acute biliary symptoms and were managed operatively. The median time to operation was significantly reduced in the ASU group (32.4 vs 25.4 hours, p=0.047), as were the proportion of operations performed after hours (19.5% vs 2.5%, p<0.001) and the median length of stay (4 vs 3 days, p<0.001). The median operating time, rate of conversion to open cholecystectomy and wound infection rates remained similar.

Conclusions

Implementation of an ASU can lead to objective differences in outcomes for patients who present with acute cholecystitis. In our study, the ASU significantly reduced time to operation, the number of operations performed after hours and length of stay.     

Remote microphone systems for preschool-age children who are hard of hearing: access and utilization

Objectives: Children who are hard of hearing (CHH) have restricted access to auditory-linguistic information. Remote-microphone (RM) systems reduce the negative consequences of limited auditory access. The purpose of this study was to characterise receipt and use of RM systems in young CHH in home and school settings.

Design: Through a combination of parent, teacher, and audiologist report, we identified children who received RM systems for home and/or school use by 4?years of age or younger. With cross-sectional surveys, parents estimated the amount of time the child used RM systems at home and school per day.

Study Sample: The participants included 217 CHH.

Results: Thirty-six percent of the children had personal RMs for home use and 50% had RM systems for school. Approximately, half of the parents reported that their children used RM systems for home use for 1–2?hours per use and RM systems for school use for 2-4?hours per day.

Conclusions: Results indicated that the majority of the CHH in the current study did not receive RM systems for home use in early childhood, but half had access to RM technology in the educational setting. High-quality research studies are needed to determine ways in which RM systems benefit pre-school-age CHH.     

Second metatarsal osteotomies for metatarsalgia: A robotic cadaveric study of the effect of osteotomy plane and metatarsal shortening on plantar pressure

Symptom relief of recalcitrant metatarsalgia can be achieved through surgical shortening of the affected metatarsal, thus decreasing plantar pressure. Theoretically an oblique metatarsal osteotomy can be oriented distal to proximal (DP) or proximal to distal (PD). We characterized the relationship between the amount of second metatarsal shortening, osteotomy plane, and plantar pressure. We hypothesized that the PD osteotomy is more effective in reducing metatarsal peak pressure and pressure time integral. We performed eight DP and eight PD second metatarsal osteotomies on eight pairs of cadaveric feet. A custom designed robotic gait simulator (RGS) generated dynamic in vitro simulations of gait. Second metatarsals were incrementally shortened, with three trials for each length. We calculated regression lines for peak pressure and pressure time integral vs. metatarsal shortening. Shortening the second metatarsal using either osteotomy significantly affected the metatarsal peak pressure and pressure time integral (first and third metatarsal increased, p < 0.01 and <0.05; second metatarsal decreased, p < 0.01). Changes in peak pressure (p = 0.0019) and pressure time integral (p = 0.0046) were more sensitive to second metatarsal shortening with the PD osteotomy than the DP osteotomy. The PD osteotomy plane reduces plantar pressure more effectively than the DP osteotomy plane. Published 2013 by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 32:385–393, 2014.     

针刺抽吸法诱导建立椎间盘退行性变的动物模型

目的:用针刺抽吸法建立椎间盘退行性变动物模型,分析其可行性和优点。方法:实验于2006-10/2007-03在苏州大学附属第一医院骨科实验室完成。新西兰大白兔18只,用持针器夹持21G皮肤穿刺针从椎间隙正前方刺入L3～4、L4～5、L5～6椎间盘的纤维环,深度控制在5mm,拔出针芯,抽吸出部分髓核组织。术前及术后4,8,12周分别对造模后椎间盘及对照椎间盘(L2～3)行免疫组织化学及组织学观察。结果:新西兰大白兔18只均进入结果分析。①组织学观察:苏木精-伊红染色可见对照组髓核组织中有着大量髓核细胞,造模组第4周髓核细胞数量不断减少,第12周时髓核中主要为纤维软骨组织,伴有极少量髓核细胞。Ⅱ型胶原免疫组织化学检测可见:对照组髓核组织间质呈强阳性染色,而各模型组呈弱阳性染色。随着造模时间的延长,染色逐渐减弱,说明髓核组织中Ⅱ型胶原的含量逐渐减少。②髓核细胞凋亡率:对照组、实验组4,8,12周的髓核细胞凋亡率为(3±1)%,(17±4)%,(36±2)%,(23±5)%,差异有显著性意义(F=113.86,P=0.0001<0.01)。结论:纤维环穿刺吸出部分髓核的方法在不破坏自身免疫屏障的前提下可诱导兔椎间盘的缓慢退行性变,为干细胞、髓核细胞、基因治疗等提供有效的动物模型。