Predictive importance of left ventricular myocardial stiffness for the prognosis of patients with congestive heart failure

SummaryObjectivesThis study was designed to determine the prognostic importance of left ventricular (LV) myocardial stiffness, a hemodynamic index which is closely related to B-type natriuretic peptide (BNP) concentration in patients with congestive heart failure (CHF).BackgroundWhile elevated BNP, an abnormality of cardiac neurohormones, is known to be an independent marker of death or re-admission, it remains to be clarified whether there is also a strong predictor directly related to cardiac dysfunction.MethodsLV performance variables and stress–strain analyses including diastolic myocardial stiffness constant (Km) were obtained from 37 patients with initial CHF by the combined simultaneous measurement of echocardiographic and hemodynamic data. Survivors were monitored for a mean of 23 months, with the main endpoint being combined death or first re-admission for CHF.ResultsTen patients (27%) were primary endpoint cases. Both Km and plasma BNP levels were higher in the event than in the event-free group. By Cox proportional hazards analysis, Km≥4.0 was identified as the only variable with significant and independently incremental predictive power to affect the primary endpoint (adjusted hazard ratio=7.354, 95% confidence interval 1.379–39.232, p=0.02).ConclusionsIn patients with CHF, increased myocardial stiffness may have greater prognostic significance compared to other conventional predictors. Increased myocardial stiffness may be considered to be an important prognostic factor independent of the loading conditions

股関節脱臼における回収寛骨臼ポリエチレンライナーの設計と摩耗への影響

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Soft‐tissue tension during total hip arthroplasty measured in four patients and predicted using a musculoskeletal model

Abstract Purpose Soft‐tissue tension around the hip joint is related to the incidence of dislocation after total hip arthroplasty (THA), but it remains difficult to quantify the soft‐tissue tension during surgery. In this study, a three‐dimensional force sensor‐instrumented modular femoral head was developed and used to quantify soft‐tissue tension during THA. The forces at the hip joint were also calculated using a three‐dimensional musculoskeletal computer model to validate the measured forces. Methods Soft‐tissue tension was investigated by measuring the hip joint forces and directions during intraoperative trialing in four patients through passive range of motion (ROM) from 0° extension to 90° flexion. A musculoskeletal model with THA, which was scaled to one of four patients, was developed. The hip joint forces were calculated under the same motion. Results Through the passive ROM, the magnitude of soft‐tissue tension was greatest when the hip was extended, decreased with flexion to 34°, and progressively increased to flexion at 90°. The mediolateral force component was relatively constant, but the supero‐inferior and anterior–posterior force components changed significantly. Within‐individual variations were small during three repeated cycles of measurement, but magnitudes varied significantly among patients. Similar force patterns and magnitudes were calculated by the musculoskeletal model. Conclusions This study demonstrates that it is possible to quantify soft‐tissue tension and direction during THA with an instrumented head. There was general agreement between the calculated and measured forces in both pattern and magnitude. Including additional subject‐specific details would further enhance agreement between the model and measured hip forces

Intermediate to Long-Term Results of Periacetabular Osteotomy in Patients Younger and Older Than Forty Years of Age

© 2011 by The Journal of Bone and Joint SurgeryBackground: The treatment of middle-aged patients with periacetabular osteotomy remains controversial. The goal of the present retrospective study was to analyze the intermediate to long-term functional and radiographic results of periacetabular osteotomy in patients below and above the age of forty years. Methods: Between February 1990 and December 2004, 166 periacetabular osteotomies were performed in 146 patients. We evaluated 158 hips in 139 patients who had a mean age of thirty-two years at the time of surgery. The mean duration of follow-up was eleven years (range, five to twenty years). We compared thirty-six patients (forty-one hips) who were forty years of age or older with 103 patients (117 hips) who were younger than forty years of age at the time of surgery. Results: The average Harris hip score increased from 70 points preoperatively to 90 points postoperatively. The mean Harris hip scores at the time of the five-year follow-up were similar in the older and younger groups (p = 0.57), although the latest follow-up scores were significantly higher in the younger group than in the older group (91 compared with 88 points; p = 0.02). The average modified Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function score (with 0 representing the worst score and 100 representing the best score) was higher for the younger group than for the older group (92 compared with 90 points; p = 0.03). Kaplan-Meier analysis with progression of the Tönnis grade of osteoarthritis as the end point showed a ten-year survival rate of 90.8% (95% confidence interval, 88.3% to 93.3%) and a fifteen-year survival rate of 83.0% (95% confidence interval, 78.5% to 87.5%); the ten-year survival rates in the younger and older groups were 94.4% and 81.3%, respectively, and the fifteen-year survival rates were 86.9% and 71.2%, respectively (p = 0.025). Conclusions: Periacetabular osteotomy yielded similar results for the two groups at the time of the five-year follow-up, although the results for the older group deteriorated thereafter. Decrease in physical function due to aging and increased susceptibility to the progression of osteoarthritis may be responsible for the poorer results over time in the older group

Hybrid total hip arthroplasty using specifically-designed stems for patients with developmental dysplasia of the hip. A minimum five-year follow-up study

AuthorA 4-U hybrid total hip arthroplasty (THA) system was specifically designed for patients with developmental dysplasia of the hip (DDH). Straight stem with an appropriate offset and various size variations are advantages. We followed 128 hips in 124 patients, 13 men and 111 women, for a mean of 6.5 years (range, 5.0-7.5 years). Two acetabular and femoral components in two patients had been revised for infection, one acetabular component had been revised for recurrent dislocation, and one femoral component had been revised for periprosthetic femoral fracture. None of the acetabular or femoral components were revised for loosening or were found to be loose at follow-up. The Harris hip score increased from a preoperative average of 42 points to 88 points at the most recent follow-up. Primary THA using the 4-U system had a good mid-term result in patients with DDH. This system could be applied for all patients including those with the narrowest and deformed femur

Hip stability after total hip arthroplasty predicted by intraoperative stability test and range of motion: a cross-sectional study

Abstract Background Dislocation continues to be a common complication following total hip arthroplasty (THA). A larger intraoperative range of motion (ROM) is believed to minimize dislocation risk, and intraoperative stability tests have been used to assess the ROM. However, it is not clear whether or not intraoperative stability tests can predict hip stability after THA. It is also unclear which angles are required in intraoperative stability tests. We investigated the usefulness of intraoperative stability tests, and other risk factors to predict hip stability after THA. Methods Patients operated by single surgeon at one hospital from June 2009 to December 2013 were evaluated. This study included 185 hips with 32 mm metal femoral head. The range of internal rotation with 90° hip flexion (IR angle) was measured as an intraoperative stability test. The variables studied as risk factors included age, height, weight, gender, cerebral dysfunction, preoperative diagnosis, history of previous hip surgery, and IR angle. Results Mean IR angle was statistically different between patients with dislocation and patients without dislocation (59.5° vs 69.6°: p = 0.006). Cerebral dysfunction and a history of previous hip surgery were statistically related with prevalence of dislocation (p = 0.021, and p = 0.011). The receiver-operating characteristic curve analysis suggested that the cutoff points for IR angle were 51° and 67°. Dislocation rate in larger IR angle group was significantly lower than the rate in smaller IR angle group when patients were divided by 51° (p = 0.002). Logistic regression analyses showed that significant risk factors were cerebral dysfunction (OR: 5.3 (95%CI 1.1–25.9); p = 0.037), history of previous hip surgery (OR: 8.6 (95%CI 1.2–63.0); p = 0.035), and IR angle (OR: 10.4 (95%CI 1.9–57.1); p = 0.007). Conclusions The results showed that intraoperative stability test, especially the IR angle, was a useful method to predict hip stability after THA, and a larger intraoperative ROM reduced the likelihood of dislocation. 51° and 67° were indicated as cutoff points for IR angle. Cerebral dysfunction and a history of previous hip surgery are also risk factors for the incidence of dislocation after THA. Trial registration This is a retrospective study, not a clinical trial defined by the World Health Organization (WHO)

Porous-Coated Cementless Acetabular Components Without Bulk Bone Graft in Revision Surgery

http://dx.doi.org/10.1016/j.arth.2009.10.012We previously reported the average 9.3-year (range, 5-13 years) results of 74 patients (83 hips) with porous-coated acetabular components that were placed without bulk bone graft at revision surgery. Since the previous report, 7 patients (7 hips) died before the minimum follow-up of 10 years, and 1 patient (1 hip) was lost to follow-up. We now report the average 15.6-year (range, 10-20 years) results for 66 patients (75 hips). Three additional acetabular components were removed or revised again: 2 for infection and 1 for dislodgement of the polyethylene liner from the metal shell. Overall, 7 (7%) components required removal or repeat revision. No shell was revised for aseptic loosening, and none was categorized as loose during the entire follow-up period

Cemented Calcar Replacement Femoral Component in Revision Hybrid Total Hip Arthroplasty

http://dx.doi.org/10.1016/j.arth.2010.02.014We evaluated intermediate-term to long-term survival of cemented calcar replacement femoral components in hybrid revision total hip arthroplasty. We followed up 52 hips in 50 patients for a mean of 11.4 years. Six (12%) femoral components had been revised: 2 for aseptic loosening, 2 for periprosthetic fracture, and 2 for deep infection. One additional femoral component was definitely loose. The number of previous revision operations (P = .004), preoperatively poorer femoral bone stock (P = .005), and postoperative poor cement mantle grading (P = .003) were significant factors for failure. Kaplan-Meier analysis revealed that the 15-year survival rate was 90% with mechanical failure as the end point. This technique remains a reasonable option for the first-time revision, especially for older and less active patients