Accuracy of the Fracture Risk Assessment Tool for judging pharmacotherapy initiation for primary osteoporosis.

INTRODUCTION: This study aimed to determine whether the Fracture Risk Assessment Tool (FRAX®) is useful in assessing the criteria for the initiation of pharmacotherapy for primary osteoporosis based on the current diagnostic criteria in Japan. MATERIALS AND METHODS: We enrolled 614 patients aged ≥ 40 years (average, 77.0 years) who were eligible for primary osteoporosis evaluation. Bone mineral density measurements of the lumbar spine, total hip, and femoral neck using ALPHYS LF (FUJIFILM, Tokyo, Japan) and imaging studies involving the lumbar spine were obtained and the FRAX® scores of each patient were calculated with and without the T-score of the femoral neck. The receiver operating characteristic curve analysis method was used to calculate the cut-off FRAX® scores with reference to the criteria for initiating pharmacotherapy for osteoporosis; the accuracies of both FRAX® scores were compared. RESULTS: The FRAX® score calculated with the T-score was more accurate for hip fracture risk assessment [cut-off value 5.5%; the area under the curve (AUC) 0.946] than for major osteoporotic fracture risk assessment (cut-off value 17.0%; AUC 0.924) in judging the criteria (p = 0.001). Conversely, the FRAX® score calculated without the T-score was equally accurate for hip fracture risk assessment (AUC 0.796) and major osteoporotic fracture risk assessment (AUC 0.806) (p = 0.23). CONCLUSION: The FRAX® score can accurately assess the criteria for initiating pharmacotherapy for primary osteoporosis based on the current Japanese diagnostic criteria, especially when the T-score is used.

Deformity analysis of the lower limb on the coronal plane in patients with rheumatoid arthritis and osteoarthritis.

OBJECTIVES: To evaluate joint orientation angles of the coronal plane in patients with rheumatoid arthritis (RA) in comparison with osteoarthritis (OA). METHODS: In total, 72 patients with RA (90 knees) and 76 patients with OA (90 knees) who underwent total knee arthroplasty were enrolled. The hip-knee-ankle (HKA) angle, mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and joint line convergence angle (JLCA) were measured on preoperative long-leg radiographs in the standing position. Student's t-test was used to assess differences in radiographic data between patients with RA and OA. RESULTS: In knees with RA and OA, the mean HKA was -3.4 ± 9.4° and -10.6 ± 8.0°, the mean mLDFA was 86.6 ± 3.7° and 88.2 ± 2.7°, the mean mMPTA was 85.9 ± 4.0° and 84.3 ± 3.7°, and the mean JLCA was 2.7 ± 4.2° and 6.8 ± 4.1°. All parameters in the knees with RA were more valgus than those with OA. CONCLUSIONS: Knees with RA had a great variability in joint orientation angles on the coronal plane; the whole lower limb alignment and the femur, tibia, and joint were more valgus in knees with RA than with OA.

NPWTi allows safe delayed free flap repair of Gustilo IIIb injuries: A prospective case series.

INTRODUCTION: Free flap lower extremity repair is associated with a high complication rate (>31%); higher rates are observed in more severe patients. In cases requiring prior systemic/local stabilization, delayed repair increases complication rate (+10% at 7 days): Negative-pressure Wound Therapy (NPWT) decreases complications but only when applied for less than 7 days. Recent limited evidence suggests that augmentation of NPWT with instillation for wound irrigation (NPWTi) might safely extend such window. This study hypothesizes that, through the combined cleansing effect of NPWT and instillation, NPWTi allows safe (low complication rate) delayed free flap repair in severe patients with Gustilo IIIb injuries (GIIIb). METHODS: A prospective case series was designed (inclusion criteria: GIIIb requiring microsurgical repair, severe patient/injury condition preventing immediate/early repair; exclusion criteria: allergy to NPWTi dressing). Patients received NPWTi (suction: 125 mmHg continuous; irrigation: NaCl 0.9%) until considered clinically ready for repair. Preoperative/postoperative complications (dehiscence, wound infection, bone non-union, osteomyelitis, flap failure) were monitored with clinical signs, imaging, and serum markers (CRP, WBC). RESULTS: Four patients (male: N = 4, female N = 1; Age: 59 [44-75] years-old) were treated. NPWTi was applied for 15.2 [9-28] days. No complication (0%) was observed preoperatively or postoperatively. Delayed repair occurred by latissimus dorsi musculocutaneous flap (N = 3), and anterolateral thigh flap (N = 2). All patients walked weight-bearing 12 [6-20] weeks after injury. CONCLUSIONS: NPWTi seems to allow safe delayed free flap repair in patients with severe lower extremity injuries unable to undergo immediate/early repair.

Medialization of the mechanical axis of the tibia is related to lateralization of the tibial tuberosity in knee osteoarthritis.

PURPOSE: To determine whether medialization of the proximal tibia due to a varus deformity is related to lateralization of the tibial tuberosity in varus knee osteoarthritis (OA). METHODS: A total of 120 knees that underwent osteotomies around the knee for varus knee OA were enrolled. Mechanical medial proximal tibial angle (mMPTA) was measured on radiographs. The angle between the mechanical and anatomical axes of the tibia (angle MA) and the distance between the centre of the tibial plateau and the anatomical axis (distance MA) were measured in the coronal plane on computed tomography images. The tibial tuberosity-posterior cruciate ligament (TT-PCL) distance, the distance between the midpoint of the tibial tuberosity and the centre of the tibial plateau (TT-centre distance), and the angle between the line through the midpoint of the tibial tuberosity and the centre of the tibial plateau and the anteroposterior axis (TT-centre angle) were measured in the axial plane. The correlations of these parameters were evaluated. RESULTS: mMPTA correlated negatively with angle MA (r = -0.37, P < 0.01) and distance MA (r = -0.55, P < 0.01). Angle MA and distance MA correlated with TT-PCL distance (r = 0.39, P < 0.01, r = 0.42, P < 0.01), TT-centre distance (r = 0.35, P < 0.01, r = 0.38, P < 0.01) and TT-centre angle (r = 0.36, P < 0.01, r = 0.36, P < 0.01). CONCLUSIONS: Medialization of the proximal tibia due to a varus deformity may induce lateralization of the tibial tuberosity.

Difference in the early postoperative change of the joint line convergence angle between opening wedge and closed wedge high tibial osteotomies.

BACKGROUND: The purpose of this study was to investigate the correction error associated with soft tissue balance in high tibial osteotomy (HTO) and the difference between opening wedge HTO (OWHTO) and closed wedge HTO (CWHTO). METHODS: A total of 170 knees of 130 patients (85 knees of 68 patients in OWHTO and 85 knees of 62 patients in CWHTO) were evaluated. Anteroposterior radiographs of the knee and full-length leg were taken preoperatively, immediately under general anesthesia postoperatively, 2 days, and 1 and 12 months postoperatively. The femorotibial angle (FTA), joint line convergence angle (JLCA), and medial proximal tibial angle (MPTA) were measured. RESULTS: The postoperative FTA was decreased from 170.5 ± 2.1° at 0 day to 168.6 ± 2.2° at 2 days in OWHTO (P < 0.05), whereas it was not changed from 168.7 ± 2.4° at 0 day to 168.1 ± 2.8° at 2 days in CWHTO. The JLCA was 4.8 ± 1.8° preoperatively, 4.2 ± 1.9° at 0 day, 2.2 ± 1.8° at 2 days (P < 0.05 vs 0 day), 2.6 ± 1.7° at 1 month, and 2.7 ± 1.6° at 12 months in OWHTO, and 7.1 ± 3.2° preoperatively, 4.1 ± 2.4° at 0 day (P < 0.05 vs preoperative), 3.4 ± 2.5° at 2 days, 3.9 ± 2.3° at 1 month, and 4.2 ± 2.6° at 12 months in CWHTO. Multiple regression analysis showed that preoperative factors affecting change of the JLCA from preoperative to postoperative 1 month were the correction angle in OWHTO (P = 0.001) and the preoperative standing JLCA in OWHTO (P < 0.001) and CWHTO (P < 0.001). CONCLUSIONS: A significant decrease of the JLCA occurred immediately after osteotomy under anesthesia in CWHTO, whereas in OWHTO there was no decrease under anesthesia, but it decreased several days postoperatively.

Increased contact area of flange and decreased wedge volume of osteotomy site by open wedge distal tibial tuberosity arc osteotomy compared to the conventional technique.

PURPOSE: The purpose of this study was to evaluate the area of the osteotomy surface, including the flange and wedge volume, in open wedge high tibial osteotomy (OWHTO), distal tibial tuberosity osteotomy (DTO), and distal tibial tuberosity arc osteotomy (DTAO) using tibial sawbones. It was hypothesized that the area of the osteotomy surface, including the flange, in DTAO was larger than that in OWHTO and DTO and that the wedge volume in DTAO was smaller than that in OWHTO and DTO. METHODS: Fifteen tibial sawbones were divided equally into three groups: OWHTO, DTO, and DTAO. The total area of the osteotomy surface in OWHTO, DTO, and DTAO was compared using image analysis software. The contact area of the flange and the wedge volume at wedge heights of 5, 10, and 15 mm were compared among osteotomy types. One-way repeated-measures analysis of variance was used to compare the total area of the osteotomy surface, the contact area of the flange, and the wedge volume at 5, 10, and 15 mm in OWHTO, DTO, and DTAO. RESULTS: The total area of the osteotomy surface in DTO and DTAO was significantly larger than that in OWHTO (P < 0.05). The contact area of the flange in DTAO was significantly larger than that in OWHTO at each wedge height (P < 0.05). In addition, the contact area of the flange in DTAO was significantly larger than that in DTO at wedge heights of 5 and 15 mm (P < 0.05). The wedge volume in DTAO was significantly smaller than that in DTO at each wedge height (P < 0.05). CONCLUSIONS: This study demonstrated that an increase in the flange contact area and a decrease in the wedge volume in the opening gap were found in DTAO compared to DTO. This would be an advantage for anteroposterior screw insertion from the flange to the distal tibial fragment and bone union at the osteotomy site.

Status of fracture risk assessment and osteoporosis treatment in Japanese patients with rheumatoid arthritis.

OBJECTIVES: This study aimed to investigate the prevalence of patients with rheumatoid arthritis (RA) at a high risk of major osteoporosis (OP)-related fractures and the status of OP-related medical treatment for these patients. METHODS: We enrolled 120 patients aged ≥40 years (average, 69.1 years) with RA. The Fracture Risk Assessment Tool (FRAX®) was used to evaluate the fracture risk. Of the 120 patients, the femoral neck bone mineral density (BMD) was evaluated in 102 patients, and their FRAX® scores were calculated alongside the BMD values. Patients observed to be at a high risk of a major OP-related fracture (10-year probability >20% or hip fracture risk >3%), according to FRAX®, were identified as those requiring OP treatment; medication ratio for OP (percentage of patients actually receiving medication among patients requiring OP treatment) was assessed. RESULTS: OP treatment was indicated in 75 (63%) patients; the medication ratio for OP was 49%. The use of biological disease-modifying anti-rheumatic drugs and corticosteroids showed a positive effect; however, the use of methotrexate showed a negative effect on the medication ratio. CONCLUSION: The number of potential patients requiring OP treatment is underestimated. All patients with RA should be assessed to determine their eligibility for OP treatment.

Reconstruction of the Necrotic Scrotum with Hydrosurgery System and Pedicle DIEP Flap: A Case Report of Fournier Gangrene.

Despite medical advances, the mortality rate associated with Fournier gangrene has remained largely unchanged and extremely high. In addition, conventional surgical treatment of Fournier gangrene of the scrotum requires excision of the testicles in some cases, which can result in loss of fertility. We report herein the favorable results of reconstruction of the scrotum following Fournier gangrene, using the hydrosurgery system and pedicled deep inferior epigastric perforator flap. A 60-year-old male patient was urgently transported to our hospital for fever, lower abdominal pain, and scrotal pain for several days. He was diagnosed with Fournier gangrene and underwent an emergency debridement procedure on the same day. Later, we performed a 2-phase reconstruction with a hydrosurgery system and pedicled deep inferior epigastric perforator flap under general anesthesia for the postoperative tissue defect. At 6 months postoperatively, there was no ulceration or scar contracture, and the results were aesthetically pleasing. There are no reported cases of reconstruction of the scrotum following Fournier gangrene using this procedure, and it might be an effective treatment option.

Reconstruction of Lower Limb Necrotizing Fasciitis by Hydrosurgical Debridement and Multiperforator Anterolateral Thigh Flap.

The authors describe a surgical treatment that optimally combined the use of the hydrosurgical system and a free multiperforator anterolateral thigh flap to prevent lower limb amputation in a severe case of necrotizing fasciitis. A 43-year-old woman was diagnosed with necrotizing fasciitis, and amputation was performed at the level of the metatarsal shafts with an emergency debridement using the hydrosurgical system. In the second reconstructive surgery, a free anterolateral thigh flap measuring 28 × 8 cm2 was harvested using the left thigh as the donor site and the vascular pedicle was made up of a total of 3 vessels, 2 perforating arteries from the descending branch of the lateral circumflex femoral artery, and 1 oblique branch from the lateral circumflex femoral artery. To thin the flap, we first resected as much subcutaneous fat as possible in the distal part of the flap (which would eventually cover the ankle joint) and ensured adequate residual volume of the proximal part of the flap (which would cover the metatarsal stumps). We then sutured the flap to the tissue defect on the left foot and then end-to-side anastomosing the lateral femoral circumflex artery and posterior tibial artery while the 2 veins were anastomosed to the posterior tibial veins under a microscope. Six months after the surgery, adequate flap volume was maintained over the metatarsal stumps with no postoperative complications such as infection or ulcer formation, and there were no other complications such as motor dysfunction at the donor site on the left thigh.

Corrigendum to "Dedifferentiated fat cells in polyglycolic acid-collagen nerve conduits promote rat facial nerve regeneration" [Regen Ther 11 (2019) 240-248].

[This corrects the article DOI: 10.1016/j.reth.2019.08.004.].

Clinical and radiological features of lumbar degenerative spondylolisthesis who complicates osteoarthritis of the knee.

BACKGROUND DATA: Correlation between lumbar degenerative disease and degenerative disorders of the knee joint have often been reported, however, detailed research concerning lumbar degenerative spondylolisthesis (DS) who complicates osteoarthritis of the knee (KOA) are scarce. METHODS: A total of 184 consecutive surgically treated DS patients were identified, and divided into two groups: DS patients who complicate KOA (KOA group) and DS patients without KOA (non-KOA group). DS was defined as grade 1 or more, according to Meyerding's classification, and KOA was defined as grade 3 or more according to Kellgren-Lawrence classification. Clinical and the radiological differences of DS patients between KOA group and non-KOA group were investigated in order to clarify the features of DS patients who complicate KOA. Statistical significance using student's t-test and multivariate logistic regression analysis was performed to identify independent predictors of complicating KOA in DS. RESULTS: KOA group and non-KOA group consisted of 57 and 127 patients, respectively, with both group predominantly of female patients. Clinical features of KOA group were significantly high in age and body mass index (BMI), and more likely to complicate circulatory system disorders than non-KOA group. Radiological features of KOA group were significantly high in frequency of double adjacent level spondylolisthesis, Pelvic incidence (PI), Pelvic tilt (PT), and PI-LL. Multivariate logistic regression analysis identified coexistence of circulatory system disorders (OR 2.251, p = 0.024) and PI-LL (OR 1.04, p < 0.001) to be an independent predictors of complicating KOA in DS patients. CONCLUSIONS: Older age and overweighted female patients coexistence of circulatory system disorders, containing double adjacent level spondylolisthesis with high PI, PT, and PI-LL were the characteristics of DS patients who complicate KOA, particularly coexistence of circulatory system disorders and significantly high lumbo-pelvic sagittal mismatch were the most significant factors above all.

Dedifferentiated fat cells in polyglycolic acid-collagen nerve conduits promote rat facial nerve regeneration.

INTRODUCTION: Polyglycolic acid (PGA) nerve conduits, an artificial biodegradable nerve regeneration-inducing tube currently used in clinical practice, are effective in regenerating peripheral nerves. Dedifferentiated fat (DFAT) cells differentiate into various cells including adipocytes, osteoblasts, chondrocytes, skeletal muscle cells, and myofibroblasts, when cultured in appropriate differentiation-inducing conditioned culture medium. This study made a hybrid artificial nerve conduit by filling a PGA conduit with DFAT cells, applied the conduit to a rat facial nerve defect model, and investigated the facial nerve regenerative ability of the conduit. METHODS: Under inhalational anesthesia, the buccal branch of the facial nerve in Lewis rats was exposed, and a 7-mm nerve defect was created. PGA nerve conduits were filled with DFAT cells, which were prepared from rat subcutaneous adipose tissue with type I collagen as a scaffold, and then grafted into the nerve defect sites in rats with a microscope (DFAT group) (n = 10). In other rats, PGA artificial nerve conduits alone were similarly grafted into the nerve defect sites (the control group) (n = 10). Reinnervation was confirmed at 13 weeks postoperatively by a retrograde tracer, followed by histological and physiological comparative studies. RESULTS: The mean number of myelinated fibers was significantly higher in DFAT group (1605 ± 806.23) than in the control group (543.6 ± 478.66). Myelin thickness was also significantly lager in DFAT group (0.57 ± 0.17 µm) than in the control group.(0.46 ± 0.14 µm). Although no significant difference was found in the amplitude of compound muscle action potential (CMAP) between DFAT group (2.84 ± 2.47 mV) and the control group (0.88 ± 0.56 mV), whisker motion was lager in DFAT group (9.22° ± 0.65°) than in the control group (1.9° ± 0.84°). CONCLUSIONS: DFAT cell-filled PGA conduits were found to promote nerve regeneration in an experimental rat facial nerve defect model.

Keratinocyte sheets prepared with temperature-responsive dishes show enhanced survival after in vivo grafting on acellular dermal matrices in a rat model of staged bi-layered skin reconstruction.

INTRODUCTION: Bi-layered skin reconstruction can be achieved by staged grafting of acellular dermal matrices (ADMs) and cultured epithelial keratinocyte sheets (KSs). Both KSs and ADMs have been used for long; yet, their combined use has shown poor effectiveness. This outcome has been related to the enzymatic treatment used in the preparation of KSs, which impairs their adhesion potential to ADMs and the formation of a basement membrane (BM). Temperature-responsive (TR) culture dishes allow for enzyme-free preparation of KSs with preservation of BMs and intercellular adhesion proteins; yet, their use has not been previously applied to staged bi-layered skin reconstruction. Using an in vivo rat model, we tested the hypothesis that TR cultures enhance KSs survival and BM preservation after sequential grafting on ADMs. METHODS: In nude rats (n = 9/group), a 9-cm [2] full-thickness dorsal skin defect was repaired with a commercial ADM. At 2 weeks after surgery, we grafted the ADM with KSs (circular, 25 mm diameter), prepared from human cells either by enzymatic Dispase treatment (DT control group) or a TR culture dish (TR experimental group). KSs survival and BMs preservation was assessed one week later by digital imaging, histology (hematoxylin & eosin), immunohistochemistry (collagen IV, pancytokeratins) and immunofluorescence (cytokeratin 1-5-6, laminin). RESULTS: The TR group showed a significantly higher KSs survival (120 ± 49 vs. 63 ± 42 mm2; p < 0.05) and epidermal thickness (165 ± 79 vs. 65 ± 54 µm; p < 0.01) compared with the control DT group, as well as higher epidermal maturation (cytokeratin) and a denser laminin and Collagen IV expression in the BMs in vitro and in vivo. CONCLUSION: These findings suggest that KSs prepared with TR culture dishes have significantly enhanced survival when grafted on ADMs; these outcomes could help improve current clinical strategies in wound care by skin reconstruction.

Full-thickness skin reconstruction with basic fibroblast growth factor-impregnated collagen-gelatin sponge.

INTRODUCTION: This study examined the usefulness of basic fibroblast growth factor impregnated collagen-gelatin sponge (bFGF-CGS) in reconstructive surgery for various acute skin defects including deep dermal burns, facial full-thickness skin defects, and finger amputations as the first clinical application. METHODS: Reconstructive surgery was performed in two stages with bFGF-CGS in 8 male subjects, ranging in age from 6 to 84 years, with acute full-thickness skin defects. Following the adequate debridement of the defect, surgeons prepared a bFGF-CGS with bFGF solution at a dose of 7-14 mg/cm2 approximately 10 min just before application and then secured the bFGF-CGS in place with non-absorbable sutures. Second-stage wound closure was performed with autologous skin grafting following adequate dermis-like tissue regeneration at the site postoperatively. Follow-up was continued for 6 months. RESULTS: Of the 8 subjects, the mean duration from the adequate vascularization of the dermis-like tissue until the second-stage autologous skin graft was 22 ± 4 days. Wound closure was achieved in all cases; the mean duration until wound closure was 32 ± 8 days. During the 6-month follow-up period, no wound infection, recurrent skin ulceration, and no exposure of tendon, bone, and cartilage were observed, and there were no cases of indirectly restricted range of motion from postoperative scar contracture and none with disfiguring scars. CONCLUSION: The authors achieved favorable outcomes following reconstructive surgery with a hybrid artificial dermis impregnated with bFGF for treating acute full-thickness skin defects. bFGF-CGS serves as a convenient regenerative device requiring no specialized medical facilities.

Treatment of Acquired Digital Arteriovenous Malformation with Progression during Pregnancy.

Acquired digital arteriovenous malformation (AVM) is a relatively rare form of AVM that occurs in the fingers. Together with a review of the literature, we report a rare case of acquired digital AVM that enlarged after pregnancy. The patient was a 32-year-old woman with the chief complaint of digital swelling accompanied by a burning sensation. During her pregnancy, the swelling of the fingers recurred, with a symptom of throbbing sensation. After giving birth, the swelling reduced but did not completely disappear. At the first visit, we observed purple discoloration and swelling of the ulnar aspect of the proximal interphalangeal joints of the left hand. Contrast-enhanced computed tomography scanning via the digital arteries of the left hand revealed a lesion showing early venous return, leading to the diagnosis of AVM. Surgery was performed under general anesthesia. The digital artery supplying the lesion was identified and dissected under a surgical microscope. At 15 months after surgery, there was no recurrence, sensory dysfunction, or mobility impairment.

Correlation between mechanical stress by finite element analysis and 18F-fluoride PET uptake in hip osteoarthritis patients.

18F-fluoride positron emission tomography (18F-fluoride PET) is a functional imaging modality used primarily to detect increased bone metabolism. Increased 18F-fluoride PET uptake suggests an association between increased bone metabolism and load stress at the subchondral level. This study therefore examined the relationship between equivalent stress distribution calculated by finite element analysis and 18F-fluoride PET uptake in patients with hip osteoarthritis. The study examined 34 hips of 17 patients who presented to our clinic with hip pain, and were diagnosed with osteoarthritis or pre-osteoarthritis. The hips with trauma, infection, or bone metastasis of cancer were excluded. Three-dimensional models of each hip were created from computed tomography data to calculate the maximum equivalent stress by finite element analysis, which was compared with the maximum standardized uptake value (SUVmax) examined by 18F-fluoride PET. The SUVmax and equivalent stress were correlated (Spearman's rank correlation coefficient ρ=0.752), and higher equivalent stress values were noted in higher SUVmax patients. The correlation between SUVmax and maximum equivalent stress in osteoarthritic hips suggests the possibility that 18F-fluoride PET detect increased bone metabolism at sites of stress concentration. This study demonstrates the correlation between mechanical stress and bone remodeling acceleration in hip osteoarthritis.

Evaluation of the time period for which real-time polymerase chain reaction detects dead bacteria.

Real-time polymerase chain reaction (PCR) is currently widely used for the diagnosis of infections. We evaluated the time after treatment during which real-time PCR can detect dead bacteria. The presence of bacterial DNA was identified by real-time PCR through methicillin-resistant Staphylococcus (MRS)-PCR and universal PCR. Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, and Escherichia coli were each killed with alcohol, antibiotics, or heat treatment in vitro. The detection periods of MRS-PCR for MRSA treated by alcohol, vancomycin, linezolid, and heat were found to be less than 16, 8, 12, and 8 weeks, respectively. The detection period of universal PCR for S. epidermidis treated by alcohol, cefazolin, and heat was less than 20, 20, and 4 weeks, whereas that for E. coli was 8, 20, and 4 weeks, respectively. The presence of detectable bacterial DNA in infected arthroplasty patients before and after successful treatment was also assessed by MRS- and universal PCR. MRS-PCR was positive in 6 patients before treatment and all became negative after a mean interval of 20.8 weeks (95% confidential interval, 13.2 to 33.7) after treatment. Universal PCR detected remnant bacterial DNA in 4 patients at a mean of 15.2 weeks (95% CI, 12.4 to 18.0) after treatment and was negative in 7 patients at a mean of 17.3 weeks (95% CI, 10.6 to 24.0) after treatment. Our studies revealed that real-time PCR detects dead bacteria for several weeks, but this capability decreases with time and is likely lost by 20 weeks after treatment.

Leg length discrepancy and lower limb alignment after total hip arthroplasty in unilateral hip osteoarthritis patients.

BACKGROUND: Leg length discrepancy (LLD) following total hip arthroplasty (THA) is a leading cause of patient dissatisfaction. However, no reports have described the influence of lower limb alignment on LLD after THA. In the present study, we firstly investigated the change in lower limb alignment after THA. Secondly, we determined the influence of lower limb alignment on LLD after THA. Thirdly, we evaluated the influence of LLD in the entire lower leg on the clinical outcomes after THA. METHODS: We followed up with 54 unilateral hip osteoarthritis (OA) patients 1 year after THA. For the radiological assessment of LLD and lower limb alignment, we obtained anteroposterior radiographs of the pelvis and both lower legs in entirety in a standing position before and 1 year after THA. The Harris Hip Score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36) were also obtained to assess the clinical outcome. RESUTS: The alignment of the affected leg, which was more valgus than the unaffected leg before THA, tended toward varus after THA, and the discrepancy between the lower limb alignments on both sides decreased. However, the alignment discrepancies that remained after THA influenced the LLD measured on the radiograph of the entire lower leg, and this LLD influenced the clinical outcome as measured by the HHS and the WOMAC score. CONCLUSIONS: LLD in the entire lower leg should be corrected for a better clinical outcome after THA.

Comparison of mechanical stress and change in bone mineral density between two types of femoral implant using finite element analysis.

Stress shielding after total hip arthroplasty (THA) remains an unsolved issue. Various patterns of mechanical stress appear according to the type of femoral stem used. To compare differences in mechanical stress conditions between Zweymuller type and fit-and-fill type stems, finite element analysis (FEA) was performed. Differences in bone mineral density (BMD) changes in the femur were also compared. Maximum stress was confirmed in Gruen zone 4, whereas zone 1 had the minimum amount of stress with both types of implant. The Zweymuller stem group had less mechanical stress and lower BMD in zone 7 than the fit-and-fill stem group. In conclusion, differences in mechanical stress may be related to changes in BMD after THA.