Metal Articulations as a Source of Total Hip Arthroplasty Pain

The consensus systematic risk stratification algorithm from the American Association of Hip and Knee Surgeons, the American Academy of Orthopaedic Surgeons, and The Hip Society summarizes clinical challenges in evaluation and treatment of metal-on-polyethylene total hip arthroplasty (THA) patients with adverse local tissue reaction (ALTR) due to mechanically assisted crevice corrosion (MACC), reviews up-to-date evidence, and identifies the areas for future research in order to provide a useful resource for orthopedic surgeons providing care to these patients. A painful THA has various intrinsic and extrinsic causes. ALTR is one of the intrinsic causes in patients with painful THA. The occurrence of ALTR due to MACC at modular junctions is likely to be multifactorial, including implant, surgical, and patient factors. Therefore, a systematic evaluation needs to involve a focused clinical history, detailed physical examination, laboratory tests, and imaging in order to identify potential differential diagnoses. There should be a low threshold to perform a systematic evaluation of patients with painful non–metal-on-metal THA, including patients with metal-on-polyethylene THA, and modular dual-mobility THA with the CoCr metal acetabular insert, as early recognition and diagnosis of ALTR due to MACC will facilitate initiation of appropriate treatment prior to significant adverse biological reactions. Specialized tests such as blood metal analysis and metal artifact reduction sequence magnetic resonance imaging are important modalities in evaluation and management of ALTR in patients with painful THA.     

毫米波局部照射的远位效应

目的探讨毫米波局部照射后,除局部效应外。对动物神经系统、内分泌器官、免疫及其他内脏、生殖器官、胚胎发育及子代有无远位效应。方法选用不同频率、不同功率密度的毫米波辐照小鼠、大鼠、豚鼠,并于照后不同时间,应用先进的技术方法,(光镜、电镜、DNA定量分析、组化、免疫组化、细胞培养、高效液相(HPLC)、RIA、RBA、TAS、畸形学分析、精神行为学分析等)从功能、形态、代谢等不同角度对实验动物进行观察分析。结果系列实验研究证明,在毫米波局部照射后确可引起远位组织、器官发生许多变化(骨髓中多核巨细胞核固缩,睾丸精管中出现多核巨细胞,肝细胞中糖原含量有变化,肝中cAMP、cGMP有起伏,G-6-P酶活性有变化,血液细胞成分有变化)。小鼠孕早期(1～2d)局部受照射,可见胚卵细胞表面一些酶活性有改变,导致胚卵着床减少;小鼠孕后期(5～15d)局部皮肤受照射,其胚胎虽未发生畸形,但其生下之后一代,学习记忆能力有所降低。结论毫米波局部照射确有远位效应。本项研究为临床毫米波的应用和防护标准的制定奠定了理论基础。     

Is a Local Administration of Parathyroid Hormone Effective to Tendon-to-Bone Healing in a Rat Rotator Cuff Repair Model?

To evaluate the effect of local parathyroid hormone (PTH) administration on rotator cuff tendon-to-bone healing in a rat model compared with systemic PTH injection and untreated controls. PTH-alginate scaffold was prepared and sustained release of PTH was confirmed. Bilateral supraspinatus tendon repairs were performed in 39 rats (group 1, supraspinatus repair only; group 2, supraspinatus repair with systemic PTH injection; group 3, supraspinatus repair with local PTH administration via an absorbable scaffold; n = 13 each). Biomechanical (cross-sectional area, mode of failure, load to failure, and ultimate stress: right side) and histological analyses (hematoxylin and eosin stain, Masson's Trichrome stain Picrosirius red stain, Immunohistochemistry for BMP2, PTH1R, ColI, and ColIII: Left side) were performed to evaluate tendon-to-bone healing quality at 8 weeks after repair, and blood test (osteocalcin and procollagen type I N-terminal pro-peptide [PINP] levels) was performed in all rats. There was no intergroup difference in the healing failure rate (p = 0.910) or failure mode (p = 0.585). Biomechanically, subjects in groups 2 and 3 exhibited significantly larger cross-sectional areas and higher ultimate failure loads and ultimate stress than those in group 1 (all p < 0.05); however, no differences were noted between groups 2 and 3 (all p > 0.05). Histologically, groups 2 and 3 exhibited more organized tendon-to-bone interface structures with higher density, parallel orientation, and collagen fiber continuity than group 1 (all p < 0.05 except collagen fiber continuity in group 1 vs. 2); however, no differences in histological parameters between groups 2 and 3 (all p > 0.05). The protein levels of bone morphogenic protein 2, PTH 1 receptor, and collagen I and III and the serum level of PINP were increased in groups 2 and 3 versus group 1 (all p < 0.05) without showing differences between groups 2 and 3 (all p > 0.05). Local PTH administration using an absorbable scaffold improved the biomechanical and histological outcomes of rotator cuff tendon-to-bone healing comparable with systemic PTH injection at 8 weeks after repair in a rat model. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:82–91, 2020     

PVC材质一次性输注泵在常用局麻药应用中的安全性研究

目的考察一次性使用输注泵与常用局麻药的相容性,评定其在临床常用局麻药物使用中的安全性。方法3种常用局麻药分别与2种液体（生理盐水及乳酸林格氏液）按临床使用浓度配伍,在不同时间点分别采用LC-MS／MS法、光阻法、高效液相色谱法测定邻苯二甲酸二-（2-乙基己基）酯（DEHP）含量、不溶性微粒和药物浓度。结果DEHP含量低于LC-MS／MS测定方法定量下限（0．072gg·mL^-1）,更低于考核标准静脉晶体溶液输注成年人（70kg）DEHP剂量上界估算值（0．005mg·kg^-1·d^-1）;48h内各实验药物在一次性使用输注泵中药物含量相对0h均〉96．0％,受试输注泵与各种药物在48h内未见明显吸附;输注泵中溶液稳定,0h每1mL粒子直径≥10μm粒子数（n=30）（35．13±14．4）粒;每1mL粒子直径≥25μm粒子数（n=30）（0．61±0．49）粒,符合中国药典2010版标准。结论研究表明本一次性使用输注泵应用于3种常用局麻药物较为稳定,其DEHP溶出、不溶性微粒及药物吸附性等方面符合安全使用要求。     

What Do We Know About Taper Corrosion in Total Hip Arthroplasty?

Mechanically assisted crevice corrosion (MACC) at metal/metal modular junctions in which at least one of the components is fabricated from cobalt-chromium alloy, has reemerged as a potential clinically significant complication in total hip arthroplasty. The clinical manifestation of MACC may include the development of an adverse local tissue reaction (ALTR), similar to what has been described in association with metal-on-metal bearing total hip and resurfacing arthroplasty. The clinical presentation of MACC-associated ALTRs may include pain and possibly late recurrent dislocations. Abnormal metal artifact reduction sequence magnetic resonance images and elevated serum metal levels (cobalt elevations out of proportion to chromium elevations) can be helpful in the diagnosis of these MACC-associated ALTRs.     

Local and regional anaesthetic techniques in wound management

Adequate pain control is vital in perioperative care. Pain affects respiratory and cardiovascular function with knock-on effects on many other organs and systems. Surgery is also recognized as one of the most frequent causes of chronic pain with surgical approach and level of pain experienced being modifiable risk factors for the development of chronic post-surgical pain.     

乡土特色的少年宫活动对中小学生积极心理品质的提升作用

目的探究乡土特色少年宫活动对学生积极心理品质的提升作用。方法采用实验组、对照组前后测实验设计,选取绵阳市某学校三年级到八年级学生共530名,随机分为实验组(n=265)和对照组(n=265)。实验组学生参与12次为期90天的乡土特色的少年宫活动,对照组处于常态。活动前后采用中国中小学生积极心理品质量表进行测量。结果①实验组和对照组在六个维度上的前测分数差异均无统计学意义(P均0.05)。②实验组在人际维度、公正维度、节制维度、超越维度上,后测分数均高于前测,差异有统计学意义(P0.05);而在认知维度和情感维度上,前、后测分数差异无统计学意义(P均0.05)。③对照组在六个维度上的前后测分数差异均无统计学意义(P均0.05)。④后测分数中,实验组在人际维度、公正维度、节制维度、超越维度上的得分均高于对照组,差异有统计学意义(P0.05);而两组在认知维度和情感维度上分数差异无统计学意义(P均0.05)。结论乡土特色的少年宫活动可能有利于提升中小学生人际、公正、节制和超越等积极心理品质。