Clinical results of hamstring autografts in anterior cruciate ligament reconstruction: a comparison of femoral knot/press-fit fixation and interference screw fixation.

PURPOSE: To compare the clinical outcomes of femoral knot/press-fit anterior cruciate ligament (ACL) reconstruction with conventional techniques using femoral interference screws. METHODS: Among patients who underwent arthroscopic ACL reconstruction with hamstring autografts, 73 were treated with either a femoral knot/press-fit technique (40 patients, group A) or femoral interference screw fixation (33 patients, group B). The clinical results of the 2 groups were retrospectively compared. The inclusion criteria were primary ACL reconstruction in active patients. The exclusion criteria were fractures, multiligamentous injuries, patients undergoing revision, or patients with contralateral ACL-deficient knees. In the femoral knot/press-fit technique, semitendinosus and gracilis tendons were prepared as 2 loops with knots. After passage through a bottleneck femoral tunnel, the grafts were fixed with a press-fit method (grafts' knots were stuck in the bottleneck of the femoral tunnel). A tie with Mersilene tape (Ethicon, Somerville, NJ) over a bone bridge for each tendon loop and an additional bioabsorbable interference screw were used for tibial fixation. RESULTS: The mean follow-up period was 38 months (range, 24 to 61 months). A significant improvement in knee function and symptoms was reported in most patients, as shown by improved Tegner scores, Lysholm knee scores, and International Knee Documentation Committee assessments (P < .01). The results of instrumented laxity testing, thigh muscle assessment, and radiologic assessment were clearly improved when compared with the preoperative status (P < .01). No statistically significant difference in outcomes could be observed between group A and group B (P = not significant). CONCLUSIONS: In this nonrandomized study, femoral knot/press-fit ACL reconstruction did not appear to provide increased anterior instability compared with that of conventional femoral interference screw ACL reconstruction. Favorable outcomes with regard to knee stability and patient satisfaction were achieved in most of our ACL-reconstructed patients using femoral knot/press-fit fixation with hamstring tendon autograft. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

One-stage arthroscopic repair of rotator cuff tears with shoulder stiffness.

PURPOSE: The purpose of this study is to describe a 1-stage treatment with concomitant arthroscopic capsular release and rotator cuff repair and present clinical outcomes with a minimum follow-up of 2 years. METHODS: Arthroscopic rotator cuff repair was performed in 211 consecutive patients. Forty-three patients had severe concomitant shoulder stiffness at the time of the repair. In the stiffness group, 1-stage arthroscopic capsular release and rotator cuff repair were performed. Preoperative mean passive forward flexion was 124°, whereas external rotation at the side was 309°. All patients were evaluated at a minimum 2-year follow-up, which included a visual analog scale score for pain, tests of muscle power and range of motion, the Constant score, and the modified American Shoulder and Elbow Surgeons shoulder evaluation form and modified University of California, Los Angeles scores. RESULTS: The mean visual analog scale score during motion at the last follow-up was 1.5 in the stiffness group and 1.3 in the non-stiffness group. In the stiffness group, forward flexion was 175° whereas external rotation at the side was 60° postoperatively; shoulder motion improved (P < .001) and was comparable with that of the contralateral side. Other functional outcome instruments showed no statistical difference between the 2 groups. CONCLUSIONS: In this study, 1-stage treatment of patients with rotator cuff tears and shoulder stiffness was performed by arthroscopic capsular release and cuff repair, and overall satisfactory results were achieved in selected patients. The results of the stiffness group in this study were statistically the same as those in the non-stiffness group. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Creation of a reflecting formula to determine a patient's indication for undergoing total knee arthroplasty.

BACKGROUND: The aim of this study was to develop, from patients' characteristics and radiography, a formula reflecting the decision for total knee arthroplasty (TKA) in patients with a painful osteoarthritic knee. METHODS: We reviewed medical records of 193 consecutive patients who had knee osteoarthritis and underwent primary TKA surgery and 133 consecutive patients with knee osteoarthritis who did not have surgery in one institution during the preceding 5 years. Two skeletal radiologists graded, from 0 to 3, radiographic joint space narrowing (JSN), osteophytes, subchondral sclerosis, and subchondral cysts. The association between the variables and outcome were calculated by the chi-squared test and multivariable logistic regression. RESULTS: Women had more TKAs than men (P = 0.002), and the TKA and non-TKA groups differed in terms of self-care ability (P < 0.001). There were no significant differences in age or body mass index between the two groups. The relevant factors in the reflective formula were age, sex, self-care ability, JSN, and osteophytes in the medial compartment. The retrospective sensitivity and specificity for patients who underwent TKA surgery were 84% and 83%, respectively. The diagnostic efficacy in retrospect evaluated by a receiver operating characteristic curve was 0.92. CONCLUSIONS: A formula reflecting the decision for TKA surgery in patients with a painful osteoarthritic knee has been developed with acceptable diagnostic efficacy obtained retrospectively. The formula should be validated by further study.

Renal insufficiency plays a crucial association factor in severe knee osteoarthritis-induced pain in patients with total knee replacement: A retrospective study.

Pain, the main symptom of osteoarthritis (OA), can lead to functional disability in patients with knee OA. Understanding the association factors related to knee pain is important since preventing OA-induced disabilities can be achieved by modifying these pain-associated issues. Therefore, this study was aimed to investigate the association factors for OA-induced knee pain in Taiwanese patients who received total knee replacements (TKR).In this retrospective study, 357 subjects who had undergone TKR at the Taipei Municipal Wan-Fang Hospital were recruited. The distribution of pain severity among patients with knee OA was evaluated. Demographic data and clinical parameters were analyzed to determine relationships between these variables and the severity of knee OA pain.Of the 357 patients studied, 54% and 33% had moderate and severe knee pain, respectively. Furthermore, a multivariate logistic regression analysis revealed that serum creatinine (>1.5 mg/dL) and an estimated glomerular filtration rate (eGFR) (<60 mL/min/1.73 m) were significantly associated with severe knee pain in OA patients. A significant correlation between severe knee pain and serum creatinine or eGFR was demonstrated by Pearson correlations.Taken together, the renal insufficiency defined by an elevated serum creatinine or a low eGFR in OA patients who required TKR was associated with severe knee pain. These variables must be considered while treating knee OA pain, especially in those patients with severe pain.

Runx2-mediated bcl-2 gene expression contributes to nitric oxide protection against hydrogen peroxide-induced osteoblast apoptosis.

Nitric oxide (NO) can regulate osteoblast activities. This study was aimed to evaluate the protective effects of pretreatment with sodium nitroprusside (SNP) as a source of NO on hydrogen peroxide-induced osteoblast insults and its possible mechanisms. Exposure of human osteosarcoma MG63 cells to hydrogen peroxide significantly increased cellular oxidative stress, but decreased ALP activity and cell viability, inducing cell apoptosis. Pretreatment with 0.3 mM SNP significantly lowered hydrogen peroxide-induced cell insults. Treatment of human MG63 cells with hydrogen peroxide inhibited Bcl-2 mRNA and protein production, but pretreatment with 0.3 mM SNP significantly ameliorated such inhibition. Sequentially, hydrogen peroxide decreased the mitochondrial membrane potential, but increased the levels of cytochrome c and caspase-3 activity. Pretreatment with 0.3 mM SNP significantly lowered such alterations. Exposure to hydrogen peroxide decreased Runx2 mRNA and protein syntheses. However, pretreatment with 0.3 mM SNP significantly lowered the suppressive effects. Runx2 knockdown using RNA interference inhibited Bcl-2 mRNA production in human MG63 cells. Protection of pretreatment with 0.3 mM SNP against hydrogen peroxide-induced alterations in ALP activity, caspase-3 activity, apoptotic cells, and cell viability were also alleviated after administration of Runx2 small interference RNA. Thus, this study shows that pretreatment with 0.3 mM SNP can protect human MG63 cells from hydrogen peroxide-induced apoptotic insults possibly via Runx2-involved regulation of bcl-2 gene expression.

Intervertebral disk degeneration related to reduced vertebral marrow perfusion at dynamic contrast-enhanced MRI.

OBJECTIVE: The purpose of this study was to use dynamic contrast-enhanced MRI to ascertain the relation between intervertebral disk degeneration and lumbar vertebral marrow blood perfusion. SUBJECTS AND METHODS: We recruited 25 patients (50 vertebral bodies) who underwent dynamic contrast-enhanced MRI of the lumbar spine. The peak signal enhancement of each vertebral body was calculated from the time signal after curve fitting of a pharmacokinetic model. We controlled for other variables that might have affected blood perfusion by assessing two vertebral bodies in each patient. The 25 patients were divided into three groups. In group 1, one of the vertebral bodies (L1 or L3) evaluated was between two adjacent normal disks and the other was between two adjacent degenerated disks. In group 2, each of the two vertebral bodies evaluated was between two normal disks. In group 3 each of the two vertebral bodies evaluated was between two degenerated disks. RESULTS: Without normalization by minimization of other variables, there were no statistically significant differences in original peak enhancement values among groups 1, 2, and 3 (p = 0.179). After normalization, the peak enhancement in group 1 (0.846 +/- 0.060) was significantly lower than that in group 2 (0.988 +/- 0.047) (p = 0.003) or group 3 (0.973 +/- 0.081) (p = 0.008). CONCLUSION: After normalization, lumbar vertebral marrow perfusion correlated well with intervertebral disk degeneration evaluated with dynamic contrast-enhanced MRI. Blood perfusion was 14% less in the vertebral body marrow between two degenerated disks than in vertebral marrow between two normal disks.

Screw trajectory affects screw cut-out risk after fixation for nondisplaced femoral neck fracture in elderly patients.

BACKGROUND: Incidence of femoral neck fracture has risen with the aging of the population and has critical implications with regard to patient death, functional dependence, and social costs. Screw fixation using triangular configurations and calcar placement are still the preferred treatment for nondisplaced femoral neck fracture, to reduce the risk of loss of reduction and nonunion. However, this method is still controversial in terms of the effects of screw trajectory, including parallel or nonparallel configurations, on fixation of femoral neck fractures. This study aimed to compare the incidence of complications between patients who have undergone fixation with a parallel or a nonparallel screw trajectory. METHODS: We retrospectively analyzed 55 patients who were older than 60 years and diagnosed with nondisplaced femoral neck fracture from March 2014 to March 2016, and who were treated with cannulated screw fixation in our institution. Patient demographics, radiographic parameters including reduction quality, screw trajectory, and complications during the follow-up period were all evaluated. RESULTS: The overall complication rate for screw fixation in elderly patients was 23.6%, and screw cut-out was the most common complication, occurring in 14.5% of all enrolled patients. Also, we found that screw cut-out occurred in more osteoporotic patients, and all screw cut-outs were in groups treated with a nonparallel screw trajectory. However, parallel screw fixation was inclined to back out more after fracture healing and had a lower risk of postoperative screw cut-out. CONCLUSIONS: Our results suggested that fixation with nonparallel screws for nondisplaced femoral neck fracture in elderly and osteoporotic patients might interfere with shortening of the femoral neck along with fracture healing, leaving patients at risk of postoperative screw cut-out from the femoral head.

Worsen depression after viscosupplementation treatment for geriatric people with knee osteoarthritis?

Background/objective: Knee osteoarthritis (OA) in older people may result in psychological impairment, including anxiety and depression. This study investigates the effect of intraarticular hyaluronic acid injection (IAHA) on geriatric patients with OA. Method: A total of 102 geriatric patients with knee OA undergoing IAHA were prospectively enrolled in this study. Geriatric Depression Scale (GDS), State-Trait Anxiety Inventory (STAI), Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and the International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), and Visual Analogue Scale (VAS) for pain were recorded. All outcomes were measured at baseline before injection and during two, four, and six month follow-ups. Results: IAHA had a significant short-term effect, relieving pain at the two month follow-up, but the effect was weaker at the four month follow-up. Both IKDC and WOMAC scores were significantly improved at the two month follow-up. Viscosupplementation did not improve STAI. GDS exhibited significant deterioration at the four month follow-up. Conclusions: Although IAHA for the treatment of OA provided short-term efficiency, it had no effects on anxiety and increased depression of geriatric people. Health education should be provided with caution before viscosupplementation treatment to manage expectations of the efficacy of treatment for geriatric OA patients.

Antecedentes/objetivo: La artrosis de rodilla (AR) en personas mayores puede causar ansiedad y depresión. Se investiga el efecto de la inyección intra-articular de ácido hialurónico (IAAH) en pacientes mayores con AR. Método: Ciento dos pacientes mayores tratados con IAAH fueron inscritos de forma prospectiva. Contestaron la Geriatric Depression Scale (GDS), State-Trait Anxiety Inventory (STAI), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC) y Visual Analogue Scale (VAS). Se evaluó antes de la inyección y durante el seguimiento a dos, cuatro y seis meses. Resultados: La IAAH produjo un efecto significativo a corto plazo, aliviando el dolor a los dos meses de seguimiento, pero el efecto fue más débil a los cuatro meses. Las puntuaciones del IKDC y WOMAC mejoraron significativamente a los dos meses de seguimiento. La visco-suplementación no mejoró la ansiedad. La GDS mostró un deterioro significativo a los cuatro meses de seguimiento. Conclusiones: Aunque la IAAH fue efectiva a corto plazo, no tuvo efectos sobre la ansiedad, y aumentó la depresión. Debe prestarse atención a la educación para la salud antes del tratamiento con viscosuplementación para controlar las expectativas de la eficacia del tratamiento en pacientes mayores con AR.

Effectiveness of Strontium Ranelate in the Treatment of Rat Model of Legg-Calve-Perthes Disease.

BACKGROUND: Legg-Calve-Perthes disease (LCPD) causes osteonecrosis of the femoral head (ONFH) by temporarily interrupting the blood supply in children. Even with potential toward bone regeneration and revascularization in LCPD, the prognosis depends on the deformity of femoral heads, and successful rate with the current treatments varies. Antiresorptive therapy such as bisphosphonate, which maintains mechanical stability of the femoral head by inhibiting necrotic bone resorption, has proven effective in animal models. However, concerns on simultaneous decline in bone turnover rate still leave room for improvement. Strontium ranelate with dual effect on inhibiting bone resorption and accelerating bone formation is presumed to be an ideal therapy for reserving sphericity of femoral heads in LCPD. MATERIALS AND METHODS: In this study of a rat model of ONFH, randomized groups of rats treated with strontium ranelate or normal saline are compared at different time points in analysis of radiological, histological, and bone morphometric changes. Gait analysis was also compared between the two groups. RESULTS: The group treated with strontium ranelate recovered their normal gait earlier than the control group did. Bone density, trabecular thickness, sphericity of the femoral head, and bone regeneration potential were also preserved in the strontium ranelate group. CONCLUSION: Strontium ranelate effectively prevented collapse of the ischemic femoral head and enhanced trabecular thickness in the rat model of LCPD. Hopefully, this preclinical experiment can improve the effectiveness of strontium ranelate treatment for pediatric ONFH.

Participation of GATA-3 in regulation of bone healing through transcriptional upregulation of bcl-xL expression.

We have previously demonstrated the expression of GATA-DNA-binding protein (GATA)-3, a transcription factor, in osteoblasts and have verified its function in transducing cell survival signaling. This translational study was further designed to evaluate the roles of GATA-3 in regulating bone healing and to explore its possible mechanisms. A metaphyseal bone defect was created in the left femurs of male ICR mice. Analysis by micro-computed topography showed that the bone volume, trabecular bone number and trabecular thickness were augmented and that the trabecular pattern factor decreased. Interestingly, immunohistological analyses showed specific expression of GATA-3 in the defect area. In addition, colocalized expression of GATA-3 and alkaline phosphatase was observed at the wound site. As the fracture healed, the amounts of phosphorylated and non-phosphorylated GATA-3 concurrently increased. Separately, GATA-3 mRNA was induced during bone healing, and, levels of Runx2 mRNA and protein were also increased. The results of confocal microscopy and co-immunoprecipitation showed an association between nuclear GATA-3 and Runx2 in the area of insult. In parallel with fracture healing, Bcl-XL mRNA was significantly triggered. A bioinformatic search revealed the existence of a GATA-3-specific DNA-binding element in the promoter region of the bcl-xL gene. Analysis by chromatin immunoprecipitation assays further demonstrated transactivation activity by which GATA-3 regulated bcl-xL gene expression. Therefore, this study shows that GATA-3 participates in the healing of bone fractures via regulating bcl-xL gene expression, owing to its association with Runx2. In the clinic, GATA-3 may be used as a biomarker for diagnoses/prognoses or as a therapeutic target for bone diseases, such as bone fractures.

Arthroscopic extended rotator interval release for treating refractory adhesive capsulitis.

PURPOSE: To present the clinical results of arthroscopic extended rotator interval release with a stretching program for treating refractory adhesive capsulitis. STUDY DESIGN: Case series; level of evidence, 4. METHODS: Arthroscopy-assisted extended rotator interval tissue release including anterior capsular was performed in 26 patients with refractory adhesive capsulitis. All rotator interval tissues, except the medial sling of the biceps, were excised and the excursion of the subscapularis tendon was restored and freely mobilized. The preoperative mean passive forward flexion was 101°, whereas external rotation at the side was 10°. Patients were followed for a minimum of 2 years and their visual analog scale for pain, muscle power, range of motion, Constant score, modified American Shoulder and Elbow Surgeons Shoulder Evaluation Form score, and modified University of California at Los Angeles score were recorded. RESULTS: Visual pain scale and the aforementioned clinical scores improved postoperatively. The patients exhibited a significant postoperative difference in forward flexion, external rotation, and internal rotation. Postoperative mean passive forward flexion was 172°, whereas external rotation at the side was 58°. There was no difference in the muscle power postoperatively including abduction, internal rotation, and external rotation. CONCLUSIONS: Our study revealed satisfactory subjective and objective clinical results after a 2-year follow-up. Arthroscopy-assisted extended rotator interval release with a stretching program could be an alternative treatment for refractory adhesive capsulitis.

Single-Stage Cartilage Repair Using Platelet-Rich Fibrin Scaffolds With Autologous Cartilaginous Grafts.

BACKGROUND: To avoid complicated procedures requiring in vitro chondrocyte expansion for cartilage repair, the development of a culture-free, 1-stage approach combining platelet-rich fibrin (PRF) and autologous cartilage grafts may be the solution. PURPOSE: To develop a feasible 1-step procedure to combine PRF and autologous cartilage grafts for articular chondral defects. STUDY DESIGN: Controlled laboratory study Methods: The chemotactic effects of PRF on chondrocytes harvested from the primary culture of rabbit cartilage were evaluated in vitro and ex vivo. The rabbit chondrocytes were cultured with different concentrations of PRF media and evaluated for their cell proliferation, chondrogenic gene expression, cell viability, and extracellular matrix synthesis abilities. For the in vivo study, the chondral defects were created on established animal models of rabbits. The gross anatomy, histology, and objective scores were evaluated to validate the treatment results. RESULTS: PRF improved the chemotaxis, proliferation, and viability of the cultured chondrocytes. The gene expression of the chondrogenic markers, including type II collagen and aggrecan, revealed that PRF induced the chondrogenic differentiation of cultured chondrocytes. PRF increased the formation and deposition of the cartilaginous matrix produced by cultured chondrocytes. The efficacy of PRF on cell viability was comparable with that of fetal bovine serum. In animal disease models, morphologic, histological, and objectively quantitative evaluation demonstrated that PRF combined with cartilage granules was feasible in facilitating chondral repair. CONCLUSION: PRF enhances the migration, proliferation, viability, and differentiation of chondrocytes, thus showing an appealing capacity for cartilage repair. The data altogether provide evidence to confirm the feasibility of 1-stage, culture-free method of combining PRF and autologous cartilage graft for repairing articular chondral defects. CLINICAL RELEVANCE: The single-stage, culture-free method of combining PRF and autologous cartilage is useful for repairing articular chondral defects. These advantages benefit clinical translation by simplifying and potentiating the efficacy of autologous cartilage transplantation.

One-stage posterior cruciate ligament inlay reconstruction combining anterior cruciate ligament reconstruction following knee dislocation.

Knee dislocation is a rare but severe injury that involves damage to the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), lateral or medial ligamentous structures, and other soft tissues or bony structures surrounding the knee joint. No consensus exists regarding the best treatment method. This work presents a method of 1-stage ACL and PCL reconstruction in which a contralateral quadriceps tendon-bone autograft with tibial inlay technique is used for the PCL and contralateral hamstring tendon autograft with suspension fixation is used for the ACL. After harvesting grafts, the patient is put in the lateral decubitus position. Under arthroscopy, the femoral tunnel for the anterolateral bundle of the PCL is created using an 8-mm reamer via a prepositioned guide pin. Next, the tibial tunnel of the ACL is created with an appropriate diameter cannulated reamer. Directed by the femoral guide instrument with a 7-mm offset, a guide pin is positioned retrograde through the tibial tunnel. A reamer is then used to create a 35-mm long closed-ended femoral tunnel for the ACL. A posterior arthrotomy for the PCL inlay technique is performed. After capsulotomy, a unicortical window is created at the footprint of the PCL and the inlay graft is fixed using a 3.5mm-cancellous screw and washer. The PCL graft is then passed into the femoral tunnel. The ACL graft is passed in a retrograde fashion using the Beath pin. The ACL graft is fixed by tying with a washer on the femoral side and by tying with a screw on the tibial side. The PCL graft is then fixed on the femoral side.

Intermuscular cavernous lymphangioma presenting with overgrowth of fat: MRI findings.

We present a case of an intermuscular cavernous lymphangioma with predominantly composed of fatty tissue. A 58-year-old man complained a palpable painless mass over his right arm for 1 month. Magnetic resonance imaging (MRI) showed a 14-cm mass with predominantly composed of fatty tissue between long and short heads of triceps muscle. There were some serpiginous structures with hyperintensity within the tumors on gradient-echo and gadolinium enhanced T1-weighted images. Histologic examination revealed a picture of intermuscular angioma predominantly composed of cavernous lymphangioma.

Morphometrical measurements of resected surface of femurs in Chinese knees: correlation to the sizing of current femoral implants.

Morphometrical data were measured in the resected femurs of seventy Chinese patients who underwent total knee arthroplasties. Two measured parameters, the anterior-posterior length of the lateral condyle and the total width of the distal condyle, were compared to the anterior-posterior length and the medial-lateral width of five femoral implants currently used in Taiwan. Three implants (Duracon, NexGen and UKnee) have a larger medial-lateral width than the total width of the resected distal condyle for a given femoral implant anterior-posterior length. These implants tend to overhang the medial-lateral width of resected femurs from Chinese patients. In addition, one femoral implant (Duracon), which has previously been shown to be suitable for use in Caucasian patients, is not suitable in Chinese patients. Our results will allow manufacturers to design femoral implants better suited to Chinese patients.

Autoclaved metal-on-cement spacer versus static spacer in two-stage revision in periprosthetic knee infection.

BACKGROUND: Periprosthetic knee infection is troublesome for Orthopedic surgeons and a catastrophy for patients. Reported rates of periprosthetic joint infection following primary total knee arthroplasty (TKA) are 0.39-2%. Two stage revision arthroplasty, which has success rates exceeding 90%, has been the gold standard for treating subacute and chronic periprosthetic infection following TKA. Antibiotic spacers, a well established means of delivering local antibiotic therapy, maintain soft tissue tension during two stage revision arthroplasty. However, controversy remains around whether static or mobile antibiotic impregnated spacers are superior for treating infection following TKA. Various mobile spacers are available, including cement-on-cement, cement-on-polyethylene and metal-on-polyethylene. In this study, the efficacy of the modified metal-on-cement spacer, consisting of reinsertion of the autoclaved femoral component and implantation of antibiotic-loaded cement in the proximal tibia, is assessed. MATERIALS AND METHODS: Records of 19 patients diagnosed as periprosthetic knee infection were reviewed in this retrospective study. Among these patients, 10 patients received first stage debridement with the autoclaved metal-on-cement spacer and 8 patients with the static spacer, who eventually underwent two-stage re-implantation, were listed in the final comparison. Patient demographics, infection eradication rates, average range of motion (ROM), surgical time and blood loss during the second-stage of the surgery, and Knee Society (KS) knee scores at last followup after revision total knee replacement were clinically evaluated. RESULTS: At a minimum of 2-year followup after re-implantation, infection eradication rates, surgical times, blood loss during the second-stage of the surgery, and KS knee score after re-implantation were similar for the two groups. Patients receiving autoclaved metal-on-cement spacers had superior ROM after re-implantation compared to that of patients with static spacers. CONCLUSIONS: The autoclaved metal-on-cement spacer is an effective and simple method for two-stage re-implantation of a periprosthetic knee infection. Through this spacer, the good interim ROM can be achieved without the additional cost of prefabricated molds or new polyethylene tibial inserts. In addition, ROM after re-implantation is better than that with static spacers.

Nitric oxide induces osteoblast apoptosis through a mitochondria-dependent pathway.

Osteoblasts contribute to bone remodeling. Nitric oxide can regulate osteoblast activities. In this study, we attempted to evaluate the pathophysiological effects of nitric oxide on osteoblasts and its possible mechanism using neonatal rat calvarial osteoblasts as the experimental model. Exposure of osteoblasts to sodium nitroprusside, a nitric oxide donor, decreased alkaline phosphatase activities and cell viability in a concentration- and time-dependent manner. Apoptotic analysis revealed that sodium nitroprusside time-dependently increased the percentages of osteoblasts undergoing apoptosis. Administration of sodium nitroprusside reduced the mitochondrial membrane potential of osteoblasts. In parallel with the mitochondrial dysfunction, levels of intracellular reactive oxygen species and cytochrome c were significantly elevated following sodium nitroprusside administration. Exposure of osteoblasts to sodium nitroprusside significantly increased caspase-3 activity. Results of this study show that nitric oxide, decomposed from sodium nitroprusside, can induce osteoblast apoptosis through a mitochondrion-dependent cascade that causes mitochondrial dysfunction, release of intracellular reactive oxygen species and cytochrome c from mitochondria to cytoplasm, and activation of caspase-3.

Control of body's center of mass motion relative to center of pressure during uphill walking in the elderly.

Uphill walking places more challenges on the locomotor system than level walking does when the two limbs work together to ensure the stability and continuous progression of the body over the base of support. With age-related degeneration older people may have more difficulty in maintaining balance during uphill walking, and may thus experience an increased risk of falling. The current study aimed to investigate using gait analysis techniques to determine the effects of age and slope angles on the control of the COM relative to the COP in terms of their inclination angles (IA) and the rate of change of IA (RCIA) during uphill walking. The elderly were found to show IAs similar to those of the young, but with reduced self-selected walking speed and RCIAs (P<0.05). After adjusting for walking speed differences, the elderly showed significantly greater excursions of IA in the sagittal plane (P<0.05) and increased RCIA at heel-strike and during single limb support (SLS) and double limb support (DLS) in the sagittal plane (P<0.05), and increased RCIA at heel-strike in the frontal plane (P<0.05). The RCIAs were significantly reduced with increasing slope angles (P<0.05). The current results show that the elderly adopted a control strategy different from the young during uphill walking, and that the IA and RCIA during walking provide a sensitive measure to differentiate individuals with different balance control abilities. The current results and findings may serve as baseline data for future clinical and ergonomic applications.

Double-bundle posterior cruciate ligament reconstruction using inlay technique with quadriceps tendon-bone autograft.

Surgical reconstruction of the posterior cruciate ligament (PCL) is indicated in a PCL-deficient knee with symptomatic instability and multiple ligament injuries. The results of the traditional tunnel method for PCL reconstruction remain uncertain. The tibial inlay method offers the benefit of preventing the acute-turn associated with transtibial reconstruction. Additionally, the double-bundled graft appears to restore normal knee laxity across the full range of flexion. This study presents an inlay technique for arthroscopic PCL reconstruction with double-bundled quadriceps tendon-patellar bone autograft. This technique offers a reasonable alternative for PCL reconstruction.