The Perioperative Nurse's Role in Table-Enhanced Anterior Total Hip Arthroplasty

The anterior approach to total hip arthroplasty (THA), when performed with the patient in the supine position, is enhanced by the use of a radiolucent, orthopedic table.This technique has numerous advantages: enhanced intraoperative fluoroscopy because of the patient's supine position on a radiolucent table, improved femoral exposure, and reduced soft tissue trauma. Criteria for patient selection is not limited as it may be for other arthroplasty techniques.The role of the perioperative nurse during an anterior THA is to ensure optimal function of the orthopedic table and provide safe patient care. A clear understanding of the surgical techniques used and the functions of the table are imperative. AORN J 90 (July 2009) 53-68. © AORN, Inc, 2009.     

手术入路对髋关节置换术后髋关节功能恢复的影响

目的探讨手术入路对髋关节置换术后髋关节功能恢复的影响。方法对386例(392髋)髋关节疾病患者行髋关节置换术,分别采用不同手术入路,并且于术前,术后2周、4周、8周、24周进行Harris评分,分析髋关节功能恢复情况。结果前外侧入路组、外侧入路组、后外侧入路组、后侧入路组及小切口入路组总有效率分别为91%、94%、97%、100%、100%。结论不同手术入路对髋关节置换术后髋关节功能恢复有一定的影响。创伤小、对髋关节干预性较小的后侧入路及小切口手术入路是髋关节功能恢复较满意的选择。     

血友病性髋关节炎患者的全髋关节置换四例报告

目的 探讨全髋关节置换术治疗血友病性髋关节炎的短、中期临床疗效。方法 回顾分析 2004 年５月至 2010 年９月,采用人工髋关节置换术治疗晚期血友病性髋关节炎患者４例。患者均为男性,年龄 34～56 岁,平均年龄 45 岁。按 Arnold and Hilgartner 分级：IV 级２例,Ｖ级２例。围手术期给予患者凝血因子替代治疗的基础上,对４例患者行人工髋关节置换术,手术采用髋关节前外侧标准入路。术中、术后监测相应凝血因子活性水平控制术后出血,密切关注并发症的发生。术后根据关节功能改善情况、Harris 评分、假体生存情况、术后并发症等评估手术治疗效果。结果 本组４例患者均获随访,随访时间９个月至７年,平均 40 个月。４例患者术后髋关节疼痛均明显减轻,３例患者术后髋关节疼痛消失,１例患者术后偶诉疼痛,但不影响生活。术后 Harris 评分：85～90 分 （优２例,良２例）,平均 87.7 分。术中出血量及引流量：平均每侧髋关节为 1210 ml。本组第１例患者术后 84 个月右侧髋臼处出现松动迹象,现拟行翻修手术治疗;余患者均未出现假体周围骨溶解及松动的征象,假体位置和力线水平均满意。１例术后出现关节内出血并切口渗血,无 DVT 和 PE 形成,无大出血及伤口感染。手术切口均Ｉ期愈合。结论 人工髋关节置换术可明显缓解晚期血友病性关节炎患者的关节疼痛,明显改善病变髋关节功能,短、中期疗效较好。合理的围手术期凝血因子替代治疗非常重要,血友病性髋关节炎行人工关节置换术难度较大,对手术技术要求很高,需要专业的手术团队并在内科医师配合下施行。     

Development of Machine Learning Algorithms to Predict Clinically Meaningful Improvement for the Patient-Reported Health State After Total Hip Arthroplasty

BackgroundFailure to achieve clinically significant outcome (CSO) improvement after total hip arthroplasty (THA) imposes a potential cost-to-risk imbalance in the context of bundle payment models. Patient perception of their health state is one component of such risk. The purpose of the current study is to develop machine learning algorithms to predict CSO for the patient-reported health state (PRHS) and build a clinical decision-making tool based on risk factors.MethodsA retrospective review of primary THA patients between 2014 and 2017 was performed. Variables considered for prediction included demographics, medical history, preoperative PRHS, and modified Harris Hip Score. The minimal clinically important difference (MCID) for the PRHS was calculated using a distribution-based method. Five supervised machine learning algorithms were developed and assessed by discrimination, calibration, Brier score, and decision curve analysis.ResultsOf 616 patients, a total of 407 (69.2%) achieved the MCID for the PRHS. The random forest algorithm achieved the best performance in the independent testing set not used for algorithm development (c-statistic 0.97, calibration intercept −0.05, calibration slope 1.45, Brier score 0.054). The most important factors for achieving the MCID were preoperative PRHS, preoperative opioid use, age, and body mass index. Individual patient-level explanations were provided for the algorithm predictions and the algorithms were incorporated into an open access digital application available here: https://sorg-apps.shinyapps.io/THA_PRHS_mcid/.ConclusionThe current study created a clinical decision-making tool based on partially modifiable risk factors for predicting CSO after THA. The tool demonstrates excellent discriminative capacity for identifying those at greatest risk for failing to achieve CSO in their current health state and may allow for preoperative health optimization.     

Revision Total Hip Arthroplasty in Patients With Ankylosing Spondylitis: Long-Term Results

BackgroundAnkylosing spondylitis (AS) is a common inflammatory spondyloarthropathy with hip involvement in 40% of patients. With the recent interest in the hip-spine interplay, the purpose of this study was to define the long-term outcomes of revision total hip arthroplasty (THA) in the setting of AS.Methods174 hips in patients with AS treated with revision THA from 1969 to 2016 were identified. Mean age at revision THA was 53 years and 76% were male. Cumulative incidences of any re-revision, reoperation, and dislocation were calculated using a competing risk analysis. Mean follow-up was 13 years.ResultsThe cumulative incidence of any re-revision after index revision THA was 7% at 5 years and 36% at 20 years. Cumulative incidence of any reoperation was 9% at 5 years and 38% at 20 years. Cumulative incidence of dislocation was 6% at 5 years and 8% at 20 years. Revision THAs performed with contemporary implants (2000-2016) had a lower but statistically nonsignificant cumulative incidence of any re-revision when compared with historical implants (before 2000) at 5 years (5% vs 8%), 10 years (11% vs 18%), and 15 years (11% vs 38%) (hazard ratio, 0.47; 95% confidence interval, 0.17-1.33; P = .016).ConclusionIn this large series of 174 revision THAs in patients with AS, the cumulative incidence of dislocation was 8% at 20 years. The 20-year cumulative incidence of any re-revision was 36%, which is similar to reported rates in patients with comparable demographic features without AS.Level of EvidenceLevel IV.     

Multivariate use of MRI biomarkers to classify histologically confirmed necrosis in symptomatic total hip arthroplasty

The failure of total hip arthroplasty (THA) is commonly associated with the necrosis of the periprosthetic tissue. To date, there is no established method to noninvasively quantify the progression of such necrosis. Magnetic resonance imaging (MRI) of soft tissues near implants has undergone a recent renaissance due to the development of multispectral metal-artifact reduction techniques. Advanced analysis of multispectral MRI has been shown capable of detecting small magnetism effects of metallic debris in periprosthetic tissue. The purpose of this study is to demonstrate the diagnostic utility of these MRI-based tissue-magnetism signatures. Together with morphological MRI metrics, such as synovial volume and thickness, these measurements are utilized as biomarkers to noninvasively detect soft-tissue necrosis in symptomatic THA patients (). All subjects underwent an advanced MRI scan before revision surgery and tissue biopsies utilized for necrosis grading. Statistical analyses demonstrated a weak, but significant positive correlation (P = .04) between MRI magnetism signatures and necrosis scores, while indicating no meaningful association between the latter and serum cobalt and chromium ion levels. Receiver-operating characteristic (ROC) analyses were then performed based on uni- and multivariate logistic regression models utilizing the measured MRI biomarkers as predictors of severe necrosis. The area under the curve of the ROC plots for MRI biomarkers as combined predictors were found to be 0.70 and 0.84 for cross-validation and precision-recall tests, respectively.     

No Differences in Midterm Sports Participation or Functional Scores After Total Hip Arthroplasty by Posterolateral Vs Anterolateral Approach

BackgroundPatients undergoing total hip arthroplasty (THA) frequently question surgeons on return to sports. We compared midterm sports participation and functional scores after THA by posterolateral approach (PLA) vs anterolateral approach (ALA).MethodsOf 1381 patients who underwent uncemented ceramic-on-ceramic THA for primary osteoarthritis, 503 were excluded because of preoperative or postoperative lower limb surgery, leaving 594 operated by PLA and 284 by ALA. Forgotten Joint Score (FJS), Oxford Hip Score (OHS), satisfaction, as well as motivation, participation, and discomfort regarding 22 sports were collected. A 1:1 matching was performed to obtain 2 groups of PLA and ALA patients with similar age, gender, body mass index, and sports motivation.ResultsMatching yielded 2 equal groups of 259 patients. There were no significant differences in FJS (P = .057), OHS (P = .685), satisfaction (P = .369), or rates of participation in light (P = .999), moderate (P = .632), or strenuous sports (P = .284). Participation in strenuous sports was reported by 50 PLA (19%) and 61 ALA (24%) patients, with differences for downhill skiing (22 vs 39), running (10 vs 19), and cross-country skiing (18 vs 10). More than 50% of motivated patients practiced most of their sports. Severe discomfort was reported similarly in PLA and ALA patients, mainly during running (13 vs 11), team ball games (9 vs 7), and downhill skiing (7 vs 8).ConclusionThere were no significant differences between PLA and ALA patients in terms of OHS, FJS, satisfaction, or sports participation rates. There is little or no evidence to promote an approach based on sports participation or functional improvement.Level of EvidenceLevel III, comparative study.     

Nicotinic acetylcholine receptor (nACh-R) agonist-induced changes in brain monoamine turnover in mice

The aim of the present study was to evaluate the effects of nicotinic acetylcholine receptor (nACh-R) agonists such as (−)-nicotine and related compounds on brain monoamine turnover. A single administration of (−)-nicotine (0.04, 0.2, 1.0, and 5.0 mg/kg SC) increased both noradrenaline (NA) and dopamine (DA) turnover in a dose-dependent manner, and the maximum effects were achieved 30 min after treatment with (−)-nicotine (1.0 mg/kg). The effect of (−)-nicotine on serotonin (5-HT) turnover was complicated; 5-HT turnover was increased at a low dose of (−)-nicotine (0.04 mg/kg) but decreased at a high dose (1.0 mg/kg). The (−)-nicotine (1.0 mg/kg)-induced changes in monoamine turnover were blocked by pretreatment with the centrally acting nACh-R channel blocker mecamylamine (2.0 mg/kg IP) but not by hexamethonium (2.0 mg/kg IP). These findings indicate that systemically administered (−)-nicotine can enhance brain NA and DA turnover and affect 5-HT turnover, both of which are mediated by central nACh-R. The changes in the monoamine turnover induced by (±)-anabasine were similar to those induced by (−)-nicotine, while (−)-lobeline and (−)-cytisine had little effect, and 1,1-dimethyl-4-phenyl-piperazinium (DMPP) increased NA and 5-HT turnover but not DA turnover at all doses tested. (S)-3-Methyl-5-(1-methyl-2-pyrrolidinyl)isoxazole (ABT-418), a selective neuronal nACh-R agonist, increased NA, DA and 5-HT turnover, but had a weaker effect on DA turnover than NA and 5-HT turnover. In addition, 9-amino-1,2,3,4-tetrahydroacridine (THA), an acetylcholine esterase inhibitor, also increased monoamine turnover in the brain. Pretreatment with mecamylamine completely blocked the THA-induced increase in NA and 5-HT turnover, but not in DA turnover, suggesting that the nACh-R system is involved in the THA-induced increase in brain NA and 5-HT turnover. On the other hand, (−)-cytisine, a partial agonist for the β2 subunit containing nACh-R, completely inhibited the nACh-R agonist-and THA-induced increases in NA turnover, but not in DA turnover, and normalized the changes in 5-HT turnover. In conclusion, the subtypes of nACh-Rs mediating DA turnover may be different from those mediating NA and 5-HT turnover in the CNS. Received: 3 April 1996 /Final version: 18 June 1996     

Functional Anatomy of the Hip Joint

BackgroundThe functional anatomy of the osteoarthritic hip joint in the sagittal plane has not been defined. The purpose of this study was to define the functional anatomy of the hip using clinical and radiographic analyses.Methods320 hips had preoperative standing and sitting lateral spine-pelvis-hip X-rays. Radiographic pelvic measurements were pelvic incidence (PI) and sacral slope (SS), and hip measurements were anteinclination (AI) and pelvic femoral angle (PFA). Pelvic tilt (PT) was calculated as PI-SS. A triangle model was created from the clinical data that illustrates the functional motion of the hip during postural changes from standing to sitting.ResultsPelvic motion was coordinated with hip motion, even with spinopelvic imbalance and stiffness. Pelvic motion (ΔSS) varied for all 5 types of imbalance, but pelvic motion (ΔSS) and acetabular motion (ΔAI) changed with a 1:1 ratio and inversely with femoral motion (ΔPFA) with a 1:1 ratio. The triangle model showed similar results with ΔSS, ΔPT, and ΔAI changing in a 1:1:1 ratio, and femur motion inversely changing with a 1:1 ratio.ConclusionThe functional anatomy of the hip joint can be visually illustrated using a triangle model. Pelvic angles SS, PT, and AI change in unison, whereas femoral motion (ΔPFA) changes inversely with pelvic motion (ΔSS) in a 1:1 ratio. This coordinated mobility explains the limitations of the Lewinnek safe zone, which include only the acetabulum.