Intraoperative Psoas Compartment Block vs Preoperative Fascia Iliaca Block for Pain Control After Direct Anterior Total Hip Arthroplasty: A Randomized Controlled Trial

Background

Modern joint arthroplasty protocols place an emphasis on minimizing patient-reported postoperative pain while minimizing opioid consumption. The use of multimodal pain management protocols has been reported to improve patient outcomes and satisfaction after total hip arthroplasty.

In-Hospital Morbidity and Postoperative Revisions After Direct Anterior vs Posterior Total Hip Arthroplasty

Background

The direct anterior approach (DAA) offers the potential for less soft tissue insult, improved early recovery, and reduced dislocation rates. However, complications are associated with the DAA, particularly during the learning curve. We compare the DAA learning curve experience with the posterior approach regarding in-hospital complications and revision rate.

Impact of Femoral Stem Design on Failure After Anterior Approach Total Hip Arthroplasty

Background

An increased rate of complications related to femoral component failure has been described with less invasive total hip arthroplasty (THA). This study evaluated the incidence of femoral complications associated with the direct anterior approach for THA.

Anomalous "VVI" Pacing of a Dual Chamber Pacemaker When Programmed in DDI(R) Mode

We describe the case of a dual chamber rate responsive pacemaker (Relay, model 294-03, Intermedics, Angleton, TX, USA) implanted in a 68-year-old male for sick sinus syndrome, which was not working properly when programmed in the DDIR mode, thus determining occasionally a sort of "VVI" pacing. However, the pacemaker performed well when programmed in the DDDR mode. We discovered that this was not a malfunction of a single device but rather a general behavior of this family of Intermedics dual chamber pacemakers (also not rate responsive), caused by a software problem.     

Clinical significance of preserving spontaneous QRS wave in the therapy of DDD pacing for sick sinus syndrome

The aim of this clinical crossover study was to elucidate the effects of atrioventricular (AV) synchronous pacing on cardiac function in patients with sick sinus syndrome (SSS). Thirty SSS patients, each with dual chamber pacemaker (DDD), were enrolled and divided into two groups based on echocardiographic findings. Group A (n = 16) had hypertensive heart disease (wall thickness 11 approximately 12 mm) or mitral or aortic regurgitation (Grade I or II). Group B (n = 14) had no organic heart disease. Three successive 3-month pacing periods were tested. For the first 3 months, long AV delay that achieved > 80% ventricular sensing was chosen. For the next 3 months, AV delay was abbreviated to achieve > 80% ventricular pacing at an optimal AV interval. For the final 3 months, the first setting was resumed. At the end of each period, M mode echocardiography, pulsed-Doppler study, and measurement of plasma brain natriuretic peptide (BNP) level were conducted. In both groups, echocardiographic parameters were not significantly changed during the evaluation. In group A, plasma BNP level was significantly higher at the end of the short AV delay period than at the long AV delay period (P = 0.009), while in group B it did not differ during each period. AV synchronous pacing (> 80% ventricular pacing) in the SSS patients with a DDD pacemaker implanted could increase the ventricular load, and it is better to preserve the spontaneous QRS with the DDD mode with prolonged AV delay in patients with mild hypertensive or valvular disease.     

Evaluation of the early hemodynamic changes in carotid arteries during ventricular and dual chamber pacing

In spite of a wide choice of pacemakers, there are some problems in making more rational clinical decisions for individual patients since mode selection and programming is usually performed on the basis of a clinical hunch. The aim of this study was to measure the differences in carotid flow in patients with a pacemaker programmed in the dual chamber and in the single chamber pacing modes. Sixty patients with implanted bipolar DDD pacemakers were enrolled in this study. Blood peak systolic velocity (PSV) and end-diastolic velocity (EDV), cross-sectional area, resistive index (RI), and pulsatility index (PI) were measured in the common (CCA), internal (ICA), and external (ECA) carotid arteries before pacemaker implantation and after dual chamber and ventricular pacing at 60 beats/min. PSVs in the left CCA (79.3 +/- 24.9 cm/s) and right CCA (84.1 +/- 18.7) were shown to significantly decrease after VVI pacing (60.1 +/- 16.6 and 62.1 +/- 20.0, respectively). There was also a similar significant decrease in PSV in the left and right ICAs and ECAs. Besides PSV, RI, and PI in the left and right CCAs, ICAs, and ECAs significantly decreased after VVI pacing. There was no similar decrease after DDD pacing. Cross-sectional area and flow volume in the CCA, ICA, and ECA were similar after DDD and VVI pacing and before pacemaker implantation suggesting that cardiac output was similar when the measurements were recorded. Carotid artery PSVs, pulsatility, and RIs were found to be significantly decreased during VVI pacing compared to baseline and DDD pacing. The greater incidence of adverse cerebral outcomes in patients with VVI rather than DDD pacing may be partly due to decreased carotid PSVs.     

关节镜下膝前交叉韧带重建术后的康复

探讨安全有效的前交叉韧带重建术后康复。方法:膝关节前交叉韧带(ACL)重建(BPTB)患者60例,按照我中心现行康复程序进行功能锻炼。术后1年进行关节活动度、肢体围度测量及问卷调查。使用等张肌力测试系统对术后3个月后坚持练习和未坚持练习患者各10例,评定双侧腿肌力,比较各项参数。结果:全部患者术后3个月恢复全范围AROM、正常ADL及患膝屈肌肌力,6—7个月恢复正常运动,大部分专业运动员恢复原有竞技性运动水平。术后坚持练习组与未坚持练习组肌力比较,伸肌最大输出功率、最大收缩速率、最大力量存在显著差异(P<0.05),伸肌疲劳系数及屈肌力量无显著差异(P>0.05)。术后1年,大腿及小腿围度较健侧有显著差异(P<0.01,P<0.05)。结论:ACL重建术后康复治疗程序安全有效,患者短期(3个月)可恢复正常AROM、ADL及患腿屈肌肌力,并逐步恢复正常运动。膝伸肌肌力需坚持长期练习,才可更好恢复。     

Tunnel enlargement after arthroscopic anterior cruciate ligament reconstruction: Comparison of bone-patellar tendon-bone and hamstring autografts

Bone tunnel enlargement associated with anterior cruciate ligament (ACL) reconstruction has recently become a topic of interest in the literature. This association was examined, along with the effect of femoral and tibial tunnel enlargement on the clinical results of ACL reconstruction performed with either bone-patellar tendon-bone (BPTB) or hamstring (HST) autografts. Forty-six patients underwent arthroscopic ACL reconstruction (23 receiving BPTB autograft and 23 HST) between March 1999 and July 2001. Thirty patients (13 receiving BPTB autograft and 17 HST) completed the last clinical and radiologic evaluations and were included in the study. The mean age of patients in the HST group was 29.8 years (range 18–39) and that in the BPTB group was 27.6 years (range 20–37). The mean follow-up period was 24.6 months (range 12–36) in HST group and 18.5 months (range 12–40) in BPTB group. The effect of tunnel enlargement on the clinical results was evaluated by comparing preoperative and postoperative Lysholm, Tegner, and International Knee Documentation Committee scores and ligament laxity measurements between and within the groups. Postoperative femoral and tibial tunnel diameters in both groups were significantly larger than their corresponding preoperative tunnel diameters. In an intergroup evaluation, the enlargement of the tibial tunnel was similar in both groups (P=.556), but the femoral tunnel diameter was significantly larger in the HST group than in the BPTB group (P>.001). Preoperative laxity of the knees significantly improved after the operations in both groups, but no difference between the groups was evident at the final follow-up visit. No correlation between tunnel widening and the clinical results of the BPTB and HST procedures was observed.     

Clinical Interest of a Sensor Driven Algorithm Limiting Ventricular Pacing Rate During Supraventricular Tachycardia in Dual Chamber Pacing

A sensor driven algorithm limiting ventricular pacing rate during supraventricular tachycardia (SVT) is included in a dual chamber rate modulated pacemaker sensitive to acceleration forces (Relay, 294-03, Intermedics Inc.). According to the intensity of concomitant exercise, the ventricular pacing rate is limited either to the programmed maximum pacing rate (MPR) or to an interim lower limit, called "conditional ventricular tracking limit" (CVTL). The MPR prevails over the CVTL when the sensor calculated pacing rate exceeds the minimal rate by more than 20 beats/mm. The purpose of the study is to determine the clinical safety and efficacy of this algorithm in patients with intermittent SVT. Method: a Relay was implanted in four patients with a bradycardia/tachycardia syndrome and in four patients with complete atrioventricular block (CAVB). All had episodes of paroxysmal atrial tachycardia. The units were programmed in DDDR: rate responsive parameters were adjusted by simulating the rate response during three levels of exercise to let the MPR override the CVTL only during strenuous exercise. Holter monitors and exercise testings were performed at 3-month follow-up. Results: in seven patients, Holter recordings showed Supraventricular arrhythmias at rest with a ventricular pacing rate limited to the CVTL. Appropriate rate increases during exercise testings were also demonstrated. Three devices had to be reprogrammed in DDIR tone patient suffering from nearly permanent atrial flutter and two patients not tolerating the CVTL pacing rate at rest). Conclusion: the CVTL algorithm is effective in protecting against high ventricular pacing rates during Supraventricular arrhythmias. It allows the selection of the DDDR mode even with a high MPR in patients with intermittent SVT.     

Dual Chamber Pacing in Hypertrophic Obstructive Cardiomyopathy: Beneficial Effect of Atrioventricular Junction Ablation for Optimal Left Ventricular Capture and Filling

Clinical improvement with dual chamber pacing bas largely been reported in patients suffering from hypertrophic obstructive cardiomyopathy and mainly attributed to the reduction of the subaortic pressure gradient. To be effective, pacing must induce a permanent and complete capture of the LV. In two patients of our collective, symptoms (angina and dyspnea NYHA Class III and/or syncopes) persisted or relapsed despite pacing. This was related to the inability to obtain full LV capture due to a too-short native PR interval. RF ablation of the AV junction was therefore performed in botb patients, resulting in permanent AV block in one and prolonged PR interval up to 310 ms in the second. Pacing was thereafter associated with an immediate and significant clinical improvement related to permanent LV capture, whatever the patient's activity. After RF ablation, the AV delay was set up to induce the best LV filling, as assessed by Doppler analysis of mitral flow. Our observations suggest that RF ablation or modification of the AV junction can be a successful procedure in some patients with residual or recurrent symptoms, when the latter result from a loss of capture or from the inability to program an AV delay tbat does not compromise the active component to LV filling. Doppler echocardiography is a simple and effective mean to assess the hemodynamic effect of AV interval modulation in this setting.