Objective : In Europe, carbon dioxide therapy has been used for treating cardiac disease and skin problems for a long time. Previously, we demonstrated that transcutaneous carbon dioxide (CO₂) application facilitated dioxygen (O₂) dissociation from hemoglobin (Hb) in the human body. Additionally, we proved that transcutaneous CO₂ application to the lower limbs of rats increased the expression of peroxisome proliferator-activated receptor (PPAR) gamma coactivator-1α (PGC-1α), vascular endothelial growth factor (VEGF) and silent mating type information regulation 2 homologs 1 (SIRT1). It also increased the number of mitochondria, and changed IIB fiber to IIA fiber in similar manner to the change that occurs after exercise. The transcutaneous CO₂ application caused a similar effect to that of exercise training in skeletal muscle and indicated the possibility of improved endurance strength. However, the effect of transcutaneous CO₂ application on endurance exercise and the recovery of muscle fatigue has not been studied. Methods : In this study, we investigated the performance of endurance exercise in rats with/without transcutaneous CO₂ application and analyzed the muscle fiber changes, capillary density and mitochondrial DNA number of the skeletal muscles after training, using activity wheels. Results： Training with CO₂ application resulted in a higher percentage of TA muscle transformed to IIA and/or IID than training alone, suggesting that transcutaneous CO₂ application may increase the production of ATP, mitochondria number, and capillary density. Therefore, transcutaneous CO₂ application might lead to muscle damage recovery. Conclusion : We suggest that transcutaneous CO₂ application has a therapeutic potential for recovery of damaged muscle after excessive exercise and rehabilitation.

BACKGROUND: Recently, various femoral head fixation devices (HFDs) for trochanteric fractures have become available. However, there are some cases in which femoral head rotation with excessive sliding of the HFD is observed and it is often followed by cutout. The purpose of this study is to compare the ability of the three types of HFDs to prevent femoral head rotation. METHODS: Between July 2005 and December 2009, 206 patients aged over 60 years with trochanteric fractures who had undergone surgical treatment using a short femoral nail in our institution were enrolled into the study. We used the gamma 3 nail (GMN) as the screw-type HFD in 66 cases, the gliding nail (GLN) as a non-cylindrical blade in 76 cases, and the proximal femoral nail antirotation (PFNA) as a cylindrical blade in 64 cases. The sliding length of HFDs and the occurrence of femoral head rotation were evaluated by assessing radiographs as the main outcome, and the results were compared among these devices. RESULTS: A comparison of the degree of sliding in the GMN group showed that femoral head rotation was observed significantly more frequently in cases with rotation. Further, it appeared that femoral head rotation occurred more frequently in comminuted fractures. However, no significant differences between the sliding lengths of the different HFDs were observed among three groups. Femoral head rotation was observed in 15 cases of GMN (22.7%), 0 case of GLN, and 5 case of PFNA (7.8%). Significant differences with regard to the occurrence of femoral head rotation were observed among the three groups. Furthermore, significant differences were also observed between GLN and PFNA with respect to the occurrence of femoral head rotation. CONCLUSIONS: The ability to stabilize femoral head appears to be greater with blade-type materials than with screw-type materials. Furthermore, we believe that a non-cylindrical blade is preferable to a cylindrical blade for the surgical treatment of comminuted, unstable trochanteric fractures in order to prevent femoral head rotation and cut-out.
Aged ; Aged, 80 and over ; Female ; Femur Head/*surgery ; Hip Fractures/*surgery ; Humans ; Internal Fixators/*statistics & numerical data ; Male ; Postoperative Complications/epidemiology ; Range of Motion, Articular/physiology ; Retrospective Studies

BACKGROUND: Currently, an algorithmic approach for deciding treatment options according to the Vancouver classification is widely used for treatment of periprosthetic femoral fractures after hip arthroplasty. However, this treatment algorithm based on the Vancouver classification lacks consideration of patient physiology and surgeon's experience (judgment), which are also important for deciding treatment options. The purpose of this study was to assess the treatment results and discuss the treatment options using a case series. METHODS: Eighteen consecutive cases with periprosthetic femoral fractures after total hip arthroplasty and hemiarthroplasty were retrospectively reviewed. A locking compression plate system was used for osteosynthesis during the study period. The fracture type was determined by the Vancouver classification. The treatment algorithm based on the Vancouver classification was generally applied, but was modified in some cases according to the surgeon's judgment. The reasons for modification of the treatment algorithm were investigated. Mobility status, ambulatory status, and social status were assessed before the fracture and at the latest follow-up. Radiological results including bony union and stem stability were also evaluated. RESULTS: Thirteen cases were treated by osteosynthesis, two by revision arthroplasty and three by conservative treatment. Four cases of type B2 fractures with a loose stem, in which revision arthroplasty is recommended according to the Vancouver classification, were treated by other options. Of these, three were treated by osteosynthesis and one was treated conservatively. The reasons why the three cases were treated by osteosynthesis were technical difficulty associated with performance of revision arthroplasty owing to severe central migration of an Austin-Moore implant in one case and subsequent severe hip contracture and low activity in two cases. The reasons for the conservative treatment in the remaining case were low activity, low-grade pain, previous wiring around the fracture and light weight. All patients obtained primary bony union and almost fully regained their prior activities. CONCLUSIONS: We suggest reaching a decision regarding treatment methods of periprosthetic femoral fractures by following the algorithmic approach of the Vancouver classification in addition to the assessment of each patient's hip joint pathology, physical status and activity, especially for type B2 fractures. The customized treatments demonstrated favorable overall results.
Aged ; Aged, 80 and over ; Algorithms ; Arthroplasty, Replacement, Hip/*adverse effects ; Female ; Femoral Fractures/classification/etiology/radiography/*surgery ; Hemiarthroplasty/adverse effects ; Humans ; Male ; Middle Aged ; Periprosthetic Fractures/classification/etiology/radiography/*surgery ; Retrospective Studies

BACKGROUND: In daily clinical practice, it is essential to properly evaluate the postoperative sliding distance of various femoral head fixation devices (HFD) for trochanteric fractures. Although it is necessary to develop an accurate and reproducible method that is unaffected by inconsistent postoperative limb position on radiography, few studies have examined which method is optimal. Therefore, the purpose of this study is to prospectively compare the accuracy and reproducibility of our four original methods in the measurement of sliding distance of the HFD. METHODS: Radiographs of plastic simulated bone implanted with Japanese proximal femoral nail antirotation were taken in five limb postures: neutral, flexion, minute internal rotation, greater external rotation, and flexion with external rotation. Orthopedic surgeons performed five measurements of the sliding distance of the HFD in each of the flowing four methods: nail axis reference (NAR), modified NAR, inner edge reference, and nail tip reference. We also assessed two clinical cases by using these methods and evaluated the intraclass correlation coefficients. RESULTS: The measured values were consistent in the NAR method regardless of limb posture, with an even smaller error when using the modified NAR method. The standard deviation (SD) was high in the nail tip reference method and extremely low in the modified NAR method. In the two clinical cases, the SD was the lowest in the modified NAR method, similar to the results using plastic simulated bone. The intraclass correlation coefficients showed the highest value in the modified NAR method. CONCLUSIONS: We conclude that the modified NAR method should be the most recommended based on its accuracy, reproducibility, and usefulness.
*Bone Nails ; *Dimensional Measurement Accuracy ; Fracture Fixation, Intramedullary/instrumentation/*methods ; Hip Fractures/*surgery ; Prospective Studies ; Reproducibility of Results