Risk factors for revision total hip arthroplasty: emphasis on the characteristics of Japanese lifestyle

Introduction  

Total hip arthroplasty (THA) is a common technique for increasing quality of life (QOL) in patients with degenerative or traumatic hip arthropathy. However, there is always a risk of THA requiring revision. The present study aimed to develop guidelines for QOL assessment and patient education by analyzing the risk factors for revision THA.     

Are BMPs Involved in Normal Nerve and Following Transection?: A Pilot Study

Bone morphogenic proteins (BMPs) may have neurotrophic functions but there is limited evidence of these functions in the peripheral nervous system. We therefore investigated the expression of BMPs and BMP receptors (BMPRs) in normal and injured peripheral nerves. In 10 of 15 Sprague-Dawley rats, a 3-mm segment of sciatic nerve was resected at the trifurcation in the thigh. One day (n = 5) and 7 days (n = 5) after transection, proximal and distal stumps were removed and immunohistochemically analyzed for BMP-2, -7, BMPR-1A, -1B, and -2. The other five animals served as normal controls. In normal nerves, BMP-2 expression was localized at Ranvier’s node, and BMP-7 and BMPR-1B were expressed in several axon-Schwann cell units, whereas other receptors were not expressed. After nerve transection, BMP-7 expression was upregulated at both proximal and distal stumps along with Schwann cell columns during Wallerian degeneration. BMPRs were also upregulated compared with the normal nerve. The upregulation in BMP expression after nerve transection suggests that BMPs may play a role in the healing response of the peripheral nerve.     

Can rhBMP-2 Containing Collagen Sponges Enhance Bone Repair in Ovariectomized Rats?: A Preliminary Study

With an aging population the frequency of postmenopausal fractures is increasing. Methods to enhance the repair of osteoporotic bone repair therefore become more important to reduce the society burden of care. We asked if absorbable collagen sponges containing recombinant human bone morphogenetic protein-2 (rhBMP-2) have the potential to enhance bone repair. We randomly assigned 40 rats into the ovariectomy and sham operation groups. A segmental defect was created in the right tibia 12 weeks after ovariectomy. rhBMP-2-containing absorbable collagen sponges were implanted into the defect in half of the animals in each group. We analyzed radiographs and histological sections and performed three-point bending tests to assess repair. Radiological scores in the rhBMP-2 applied rats were higher than those in controls at the end of 8 weeks after tibial osteotomy. The specimens failed under higher loads in the rhBMP-2-applied groups and histology revealed a higher fracture healing score, including callus formation, bone union, marrow changes, and cortex remodeling. We observed no adverse tissue responses such as fibrous connective tissue formation and inflammatory cellular infiltration. rhBMP-2 in absorbable collagen sponges enhanced bone repair in segmental tibial defects of ovariectomized rats. The sponges with rhBMP-2 appeared to enhance bone repair.     

Successful repair for a giant coronary artery aneurysm with coronary arteriovenous fistula complicated by both right- and left-sided infective endocarditis

We report a rare case of a 65-year-old woman who underwent an emergent lifesaving heart operation for an undiagnosed right coronary artery aneurysm with a coronary arteriovenous fistula complicated by active infective endocarditis, which affected the aortic valve, mitral valve, and coronary sinus. We performed direct closure of the coronary arteriovenous fistula, ligation of the right coronary artery aneurysm, double coronary artery bypass grafting, and double valvular replacement. Five years after the operation, she had no sign of congestive heart failure or infection, and was not receiving antibiotics.     

Lung cancer screening and its efficacy

The efficacy of lung cancer screening should not be evaluated by the survival rate of lung cancer patients but by lung cancer mortality in a certain population because the survival rate can be greatly affected by several types of bias. Randomized controlled trials that were conducted during the 1970s and 1980s in Europe and the United States failed to prove the efficacy of lung cancer screening in decreasing the mortality rate; but recently the results of case-control studies in Japan have revealed that undergoing currently available screening decreases the risk of lung cancer deaths by 30%–60%. A system is now being created in Japan whereby the guidelines regarding cancer screening will continue to be updated. The preliminary reports concerning lung cancer screening using thoracic computed tomography revealed that not only the detection rate of lung cancer but also the survival rate of detected lung cancer patients were surprisingly high. However, the presence of some potential bias in these studies cannot be ignored; therefore, it is still unknown whether there is actual efficacy. Several randomized controlled trials are presently in progress overseas, but the interim results were not favorable. A randomized controlled trial should therefore immediately be started in Japan as well.     

Herniated nucleus pulposus in isthmic spondylolisthesis: higher incidence of foraminal and extraforaminal types

Background  

The purpose of this study was to evaluate the pattern of disc herniation and to investigate the associated symptoms in cases of isthmic spondylolisthesis. It is well known that the pathogenesis of degenerative spondylolisthesis associates with disc degeneration, followed by facet laxity and ligamentum flavum hypertrophy, which result in severe spinal canal stenosis. But isthmic spondylolisthesis is known to have a different pathogenesis. In isthmic spondylolisthesis, pseudodisc bulging is easily identified, and canal stenosis is comparatively rare. Therefore, we propose that isthmic spondylolisthesis has a different pattern of disc herniation from degenerative spondylolisthesis. We studied the type, incidence of disc herniation and clinical symptoms related to isthmic spondylolisthesis.     

Value of Laparoscopic Appendectomy in the Elderly Patient

Background  Acute appendicitis (AA) in elderly patients (60 years of age and older) is a challenging problem associated with significant morbidity and mortality when perforation is present. We hypothesized that laparoscopic appendectomy (LA) would enable an earlier correct diagnosis and have advantages in elderly patients. Methods  We performed a retrospective review of patients who underwent laparoscopic appendectomy for suspected AA. Data of elderly patients were compared to data of younger patients (18 to <60 years of age). Results  Fifty-four LA were performed in elderly patients and 423 in younger patients. Patients over the age of 60 years had more co-morbidities and required more frequent use of anticoagulants. Preoperative imaging (ultrasound or computerized tomography) was significantly more frequent in elderly patients (36% versus 15%), and was associated with a higher rate of confirmation of acute appendicitis (78% versus 55%), which allowed a decrease in the rate of negative surgical explorations to 4.1% in elderly patients compared to 10.2% in younger patients. Complicated appendicitis and conversions were more frequent in the elderly patients. This resulted in prolonged operative time and longer hospital stay for this group. The overall complication rate was equivalent in the two groups, without differences in the occurrence either of infectious complications or of complications related to surgical site. There were no deaths following appendectomy in our series. Conclusions  Laparoscopic appendectomy is safe in the elderly population and is not associated with any increase in morbidity. The high incidence of complicated appendicitis in elderly patients affects operative time and length of hospital stay following laparoscopic appendectomy, and it can also lead to an increased rate of conversion to an open procedure. Use of preoperative abdominal computerized tomography scan is mandatory in elderly patients to provide an early diagnosis and to decrease unnecessary surgical exploration when acute appendicitis is suspected.     

Indomethacin,ibuprofen and gentamicin administered during late stages of glomerulogenesis do not reduce glomerular number at 14 days of age in the neonatal rat

Premature neonates are frequently administered indomethacin, ibuprofen and gentamicin during the period of active glomerulogenesis. These drugs are known to have nephrotoxic effects, but the morphological effect of these drugs is unknown. The purpose of this study was to determine whether administration of these drugs during the late stages of glomerulogenesis in the rat has an effect on glomerular endowment. Rat pups were given, intraperitoneally, indomethacin, ibuprofen or indomethacin and gentamicin for the first 5 days of their postnatal life. The pups were killed at 14 days of age at completion of glomerulogenesis. The total number of glomeruli in the left kidney was determined by the physical disector/fractionator stereological technique. There was no difference between treatment groups in total number of glomeruli per kidney (P = 0.45). There were significantly fewer glomeruli per gram of kidney in those rat pups that had received indomethacin or ibuprofen (P < 0.0001). The reduction in the number of glomeruli per gram of kidney may indicate augmented growth of nephron tubules and/or collecting ducts, and/or be a consequence of oedema secondary to drug exposure. Further study is required to determine whether reduced glomerular number is seen in older animals or following exposure to these drugs at different time-points in kidney development.