A Patient with Acute Necrotizing Fasciitis after a Total Knee Replacement: A Case Report.

Necrotizing fasciitis is a relatively rare and serious fatal soft-tissue infection that is characterized by a rapidly spreading bacterial infection located in the subcutaneous tissues. We report a 59-year-old man who was diagnosed with acute necrotizing fasciitis, following a primary total knee replacement. He received primary total knee replacement that was uneventful and smooth intraoperatively. An immediate high fever was reported in the next few days, with several complications, confirming a diagnosis of necrotizing fasciitis. The most effective treatment for this disease is a rapid primary diagnosis and surgical debridement. Gold standard treatment includes intravenous therapy, such as antibiotics, surgical debridement, and intensive care. As a result of possible GI complications that triggered necrotizing fasciitis, the patient underwent flap reconstruction. This report's aim is to review the comprehensive treatment, management, and experience of necrotizing fasciitis, highlighting the roles with a multidisciplinary care team for improving the condition of this patient.

The Association between Osteoporosis and Peripheral Artery Disease: A Population-Based Longitudinal Follow-Up Study in Taiwan.

Background: There are several possible links that have been used to claim that osteoporosis and peripheral artery disease (PAD) are associated; however, the solid evidence is not sufficient. This study aimed to use the Taiwan National Health Insurance Research Database (NHIRD) to determine if osteoporosis is associated with peripheral artery disease (PAD). Method: NHIRD records from 23 million patients were collected to recruit two matched cohort groups: 64,562 patients with and 64,562 patients without osteoporosis. To compare the crude hazard ratio (HR) and the incidence rate ratio between the two cohort groups for PAD, the Cox model was used. Result: With an adjusted HR of 1.18 (95% CI, 1.08-1.29), the osteoporosis cohort group had a significantly greater risk for PAD than the group without osteoporosis. The cumulative incidence of PAD in the cohort group was also statistically higher than it was in the group without osteoporosis (1.71% and 1.39%; p ≤ 0.0001, log-rank) over the 10-year follow-up period. In addition, the osteoporotic patients with ischemic stroke, chronic obstructive pulmonary disease (COPD), and congestive heart failure (CHF) had a significantly increased risk of PAD based on subgroup analysis. Conclusions: There was a positive association between osteoporosis and the development of PAD, as patients with osteoporosis had an increased incidence of PAD over time.

The association between coronary artery disease and osteoporosis: a population-based longitudinal study in Taiwan.

PURPOSE: This large population-based study is the first to analyze the association between coronary artery disease (CAD) and osteoporosis (OP) from the National Health Insurance Research Database (NHIRD) in Taiwan to determine if CAD is associated with OP. METHODS: Data from NHIRD, a national, population-based, retrospective, matched cohort study of 23 million patients, were collected to recruit two matched cohorts: with (n = 192,367) and without (n = 192,367) CAD. The Cox model was used to compare the incidence rate ratio and crude hazard ratio (HR) between the two cohorts for osteoporotic fracture and OP. RESULTS: The CAD cohort had a significantly increased risk for vertebral compression fracture, with an adjusted HR of 1.74 (95% CI, 1.60-1.89). The cumulative incidence of OP was also statistically higher in the cohort versus without CAD (11.6% vs. 5.6%; p ≤ 0.0001, log-rank) during the 10-year follow-up period. The Cox model showed a 2.04-fold increase in the incidence of OP in the CAD cohort, with an adjusted HR of 2.04 (95% confidence interval [CI], 1.99-2.08). CONCLUSIONS: A positive association exists between CAD and development of subsequent osteoporotic fracture and OP. Patients with CAD have a significantly increased risk of developing vertebral compression fracture and a higher incident rate ratio of OP. TRIAL REGISTRATION: IRB approval number: No. C108094 on February 19, 2020.

Prospective Application of Partially Digested Autologous Chondrocyte for Meniscus Tissue Engineering.

BACKGROUND: Meniscus tissue engineering has yet to achieve clinical application because it requires chondrogenic induction and in vitro cell expansion. Contrarily, cartilage engineering from autologous chondrocytes has been successfully applied in one-stage surgery. If the natural chondrogenic potential of meniscus cells can be demonstrated, meniscus tissue engineering would have more value in clinical settings. MATERIALS AND METHODS: In total, 10 menisci and pieces of cartilage were obtained during total knee replacements. The tissues were collected for cell isolation and expansion. Their chondrogenic properties were examined by immunohistofluorescence and gene expression analyses. RESULTS: In native cartilage, immunofluorescence demonstrated the presence of collagen I, aggrecan, and traces of collagen I, whereas comparable staining was seen in the inner and middle meniscus. The presence of collagen I but the absence of collagen II and aggrecan were observed in the outer meniscus. In passage 2, chondrocytes showed the presence of collagen II and aggrecan, and the absence of vimentin. The vimentin and aggrecan staining were comparable in the inner and middle meniscus cells, whereas the outer cells showed only vimentin staining. In the gene expression analyses, the expressions of collagen II and aggrecan in the native chondrocyte and the inner and middle meniscus were higher than those of the cells from the outer meniscus, but they were not different in collagen I. In the passage 2 culture, chondrocytes had a higher expression of collagen II and aggrecan than the meniscus cells. Cells from the inner and middle areas had higher collagen II and aggrecan expression than those from the outer meniscus. CONCLUSION: Without chondrogenic induction, inner and middle meniscus cells possess a chondrogenic phenotype. Specifically, native meniscus cells exhibited more robust chondrogenic potential compared with those of the passage 2 monolayer culture.

Analysis of the following Related Surgeries of Unicompartmental Knee Arthroplasty and Total Knee Arthroplasty: A Taiwanese National Health Insurance Research Database Population-Based Study.

BACKGROUND: Current treatment options for both unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) are still controversial with no consistent results in which one is superior to others. This is the first study to examine and analyze the following related data available in patients receiving either UKA or TKA from the National Health Research Database (NHIRD) in Taiwan. METHODS: The database was searched from NHIRD, pooling one million random patients. Patients' age, gender, and comorbidities were analyzed in either UKA or TKA between January 2005 and December 2013, or up until death. For the patients that had received bilateral surgeries, further subgrouping was divided into TKA to TKA, UKA to UKA, TKA to UKA, and UKA to TKA to analyze the completion rate curve. Additional analysis of the order codes 64202B, 64053B, and 64198B was defined as failures, and the related failure rate curves were analyzed separately within ten years. Finally, infection-related codes were analyzed. RESULTS: 6,179 patients (n = 276 UKA; n = 5903 TKA) were selected. Age (p < 0.0001) and gender (p = 0.037) had significant differences, with more young population and males having UKA than TKA. Most comorbidities had no significant difference. For the bilateral surgery analysis, the UKA to UKA group had the fastest completion rate (p < 0.001) and UKA to TKA was the slowest. There were no significant differences in the failure rates of 64202B, 64053B, and 64198B. CONCLUSION: Most UKA and TKA are appropriate solutions to treat patients with osteoarthritis or osteonecrosis. UKA to UKA is the quickest bilateral completion surgery, and UKA has a higher chance of undergoing revision surgery than TKA.

The five year outcome of a clinical feasibility study using a biphasic construct with minced autologous cartilage to repair osteochondral defects in the knee.

PURPOSE: Autologous minced cartilage has been used to repair cartilage defects. We have developed a biphasic cylindrical osteochondral construct for such use in human knees, and report the five year post-operative outcomes. METHODS: Ten patients with symptomatic osteochondral lesion at femoral condyles were treated by replacing pathological tissue with the osteochondral composites, each consisted a DL-poly-lactide-co-glycolide chondral phase and a DL-poly-lactide-co-glycolide/ß-tricalcium phosphate osseous phase. A flat chamber between the two phases served as a reservoir to house double-minced (mechanical pulverization and enzymatical dissociation) autologous cartilage graft. The osteochondral lesion was drill-fashioned a pit of identical dimensions as the construct. Graft-laden construct was press fit to the pit. Post-operative outcome was evaluated using Knee Injury and Osteoarthritis Outcome Score (KOOS) up to five years. Regenerated tissue was sampled with arthroscopic needle biopsy for histology at one year, and imaged with magnetic resonance at one, three, and five years to evaluate the neocartilage with MOCART chart. Subchondral bone integration was evaluated with computed tomography at three and five years. RESULTS: Nine patients completed the five-year follow-up. Post-operative mean KOOS, except that of the "symptom" subscale, had been significantly higher than pre-operation from one year and maintained to five years. The change of MOCRAT scores of the regenerated cartilage paralleled the change of KOOS. The osseous phase remained mineralized during the five-year period, yet did not fully integrate with the host bone. CONCLUSIONS: This novel construct for chondrocyte implantation yielded promising mid-term outcome. It repaired the osteochondral lesion with hyaline-like cartilage durable for at least five years.

Collagenase treatment of cartilaginous matrix promotes fusion of adjacent cartilage.

In articular cartilage-repair, grafts usually fuse unsatisfactorily with surrounding host cartilage. Enzymatic dissociation of cartilaginous matrix to free chondrocytes may benefit fusion. We tested such a hypothesis with human cartilage in vitro, and with porcine cartilage in vivo. Human articular cartilage was collected from knee surgeries, cut into disc-and-ring sets, and randomly distributed into three groups: disc-and-ring sets in Group 1 were left untreated; in Group 2 only discs, and in Group 3 both discs and rings were treated with enzyme. Each disc-and-ring reassembly was cultured in a perfusion system for 14 days; expression of cartilage marker proteins and genes was evaluated by immunohistochemistry and PCR. Porcine articular cartilage from knees was similarly fashioned into disc-and-ring combinations. Specimens were randomly distributed into a control group without further treatment, and an experimental group with both disc and ring treated with enzyme. Each disc-and-ring reassembly was transplanted into subcutaneous space of a nude mouse for 30 days, and retrieved to examine disc-ring interface. In in vitro study with human cartilage, a visible gap remained at disc-ring interfaces in Group 1, yet became indiscernible in Group 2 and 3. Marker genes, including type II collagen, aggrecan and Sox 9, were well expressed by chondrocytes in all specimens, indicating that chondrocytes' phenotype retained regardless of enzymatic treatment. Similar results were found inin vivo study with porcine cartilage. Enzymatic dissociation of cartilaginous matrix promotes fusion of adjacent cartilage. The clinical relevance may be a novel method to facilitate integration of repaired cartilage in joints.

Sulfation pattern of chondroitin sulfate in human osteoarthritis cartilages reveals a lower level of chondroitin-4-sulfate.

Chondroitin sulfates (CS) account for more than 80% of the glycosaminoglycans of articular cartilage, which impart its physiological functions. We quantified the absolute concentration of the CS components of the full thickness cartilages from the knees of patients with terminal-phase osteoarthritis. Osteochondrol biopsies were removed from the medial femoral condyle and lateral femoral condyle of sixty female patients received total knee arthroplasty, aged from 58 to 83 years old. We found the total CS concentrations and chondroitin-4-sulfate disaccharide were significantly lowered in osteoarthritic samples. Microstructure analysis indicated while chondroitin-0-sulfate was equally distributed across different zones of the osteoarthritic cartilages, chondroitin-4-sulfate is significantly less in the deep zones. Down-regulation of sulfotransferases, the enzymes responsible for CS sulfation, in the lesion site of cartilage were observed. Our study suggested chondroitin-4-sulfate down-regulation can be a diagnostic marker for degraded osteoarthritis cartilage, with potential implications in cartilage regeneration.

Topical anesthesia for staple removal from surgical wounds on the knee: a prospective, double-blind, randomized trial.

BACKGROUND: Staple removal from surgical wounds is painful. Only a few articles have provided expert opinions using anesthetic cream for such a problem; however, direct application of the anesthetic cream to a wound may cause infection. A safe alternative can be an anesthetic patch without wound contact. MATERIALS AND METHODS: This was a prospective, double-blind, randomized clinical trial. Sixty patients who underwent primary total knee replacement were assigned to an experimental group or control group. One lidocaine patch was applied around the surgical wound for each patient in the experimental group. Alternatively, the adhesive sides of the lidocaine patches were shielded with waterproof films in the control group. A resident peeled off the patch before a single nursing practitioner removed the staples. Pain was assessed with the 10-cm visual analog scale, and a face pain scale-revised was performed. The patients and the nursing practitioner were blind to the management. RESULTS: Mean visual analog scale and face pain scale-revised scores were significantly lower in the experimental group. The mean pain score was significantly lower in the experimental group if the application time was >47 min; for patients with application time of 47 min or shorter, the score was comparable with the mean pain scores of the control group (P = 0.215). CONCLUSIONS: Removal of the metal skin staples after total knee arthroplasty is associated with moderate-to-severe pain. The lidocaine patch applied topically around the surgical wound could effectively reduce the pain during the procedure, without remarkable complications such as systemic adverse effects or wound contamination.

Local bone quality affects the outcome of prosthetic total knee arthroplasty.

Osteoporosis and osteoarthritis commonly coexist in the elderly. In patients undergoing prosthetic total knee arthroplasty (TKA), the bone quality around the knee joint may affect the safety of prosthetic implantation and consequently satisfaction with the surgical outcome. We recruited 50 postmenopausal women undergoing TKA for primary osteoarthritis; 43 completed the study protocol. The bone quality parameters of the operated knee, including bone mineral density assessed using dual-energy X-ray absorptiometry and microarchitecture variables assessed using micro-computed tomography, were determined. Surgical outcomes were assessed according to immediate (<1 week) postoperative pain quantified using the visual analog scale and knee function quantified using the Knee Injury and Osteoarthritis Outcome Score (KOOS) at 2 and 6 months postoperatively. The influence of bone quality parameters on surgical outcomes was analyzed using simple and multiple regression analyses. Volumetric bone mineral density (R(2) = 0.187-0.234, p < 0.01), the structural model index (R(2) = 0.103-0.181, p < 0.05), and trabecular separation (R(2) = 0.289-0.424, p < 0.05) were significantly associated with postoperative pain and improvement according to the KOOS. In conclusion, local bone quality, including mineral content and microarchitecture, affects the surgical outcome of TKA.

Clinical characteristics, microbiology, and outcomes of prosthetic joint infection in Taiwan.

BACKGROUND: Prosthetic joint infection (PJI) after total knee or hip replacement is a devastating complication associated with substantial morbidity and economic cost. The incidence of prosthetic joint infection is increasing as the use of mechanical joint replacement increases. The treatment approach to prosthetic joint infection is based on different clinical situations such as a patient's comorbidities, epidemic microbiology data, and surgical procedures. The aim of our study was to understand clinical characteristics of prosthetic joint infection, the microbiology of the prosthetic joint infection, and the outcomes of different treatment strategies during 2006-2011. METHODS: We retrospectively collected cases of prosthetic joint infection in the National Taiwan University Hospital between January 1, 2006 and December 31, 2011. The patients' characteristics, microbiology, outcomes, and factors associated with treatment success were recorded. RESULTS: One hundred and forty-four patients were identified as having PJI. Of these, 92 patients were entered into per-protocol analysis. Staphylococcus aureus was the most common causative organism (29.9%), followed by coagulase-negative Staphylococci (16.7%), and Enterococci (9.7%). The overall treatment success rate was 50%. Patients who received a two-stage revision had a better outcome, compared to patients who underwent other types of surgeries (70% vs. 32.7%, respectively; p < 0.001). In multivariate analysis, the two-stage revision was significantly associated with treatment success (odds ratio = 3.923, 95% confidence interval = 1.53-10.04). CONCLUSION: Our study demonstrates that Staphylococcus aureus was the most common causative organisms in PJI. Performing two-stage revisions was significantly associated with a better outcome.

Proteomic analysis of osteoarthritic chondrocyte reveals the hyaluronic acid-regulated proteins involved in chondroprotective effect under oxidative stress.

Osteoarthritis (OA), the most common type of arthritis, is a degenerative joint disease. Oxidative stress is well known to play important roles in cartilage degradation and pathogenesis of OA. The intra-articular injection of hyaluronic acid (IAHA) is accepted as an effective clinical therapy for OA, but we do not yet fully understand the mechanisms underlying the effects of HA on OA chondrocytes under oxidative stress. Here, we show for the first time that IAHA significantly reduces the synovial fluid levels of hydrogen peroxide (H2O2) and superoxide (O2(-)) in patients with knee OA. We also demonstrate that HA suppresses H2O2-induced cell death in human OA chondrocytes. Proteomic approaches (2-DE combined with mass spectrometry) allowed us to identify 13 protein spots corresponding to 12 non-redundant proteins as HA-regulated proteins in OA chondrocytes under oxidative stress. The expression levels of three putative HA-regulated proteins (TALDO, ANXA1 and EF2) in control, H2O2-, HA- and HA/H2O2-treated OA chondrocytes were verified by Western blotting and the results indeed support the notion that HA acts in anti-oxidation, anti-apoptosis, and the promotion of cell survival. Our results collectively demonstrate the utility of proteomic approaches and provide new insights into the chondroprotective effects of HA on OA. BIOLOGICAL SIGNIFICANCE: In the present study, we show for the first time that IAHA reduces the levels of H2O2 and O2(-) in synovial fluids from OA patients. We used primary cultured human OA chondrocytes as a model, treated cells with H2O2 to partly mimic their physiological conditions under oxidative stress, and examined the protection effects of HA. The proteomic approach allowed us to identify candidate proteins regulated by H2O2 and/or HA in OA chondrocytes. We found that proteins functioning in stress responses, apoptosis and protein synthesis were consistently regulated by HA in chondrocytes under oxidative stress. These novel results contribute to our understanding of the molecular mechanisms underlying HA-mediated chondroprotection.

Effects of methylprednisolone on femoral bone marrow: age-dependent susceptibility.

PURPOSE: We aimed to test our primary hypothesis that the effects of methylprednisolone on bone marrow in chickens are age-sensitive and increase with prolonged treatment and our secondary hypothesis that the effects of methylprednisolone on bone marrow can have individual effects. METHODS: Sixteen control (group A) and 29 methylprednisolone-treated (group B) chickens were categorised by age: pubertal chicks (subgroups A1, B1), young hens (A2, B2), and adult hens (A3, B3). Histologic evaluation 12 to 50 weeks after the start of methylprednisolone treatment included fat cell proliferation, trabecular bone loss, necrosis of bone and marrow, and new bone formation in the femoral head, neck, and intertrochanteric area. RESULTS: There were significant differences between groups A1 and B1 in new bone formation in the femoral neck (P = 0.048) and fat cell proliferation in the femoral head (P = 0.008) and neck (P = 0.048). New bone formation in the femoral head was also significantly different (P = 0.023) between groups A2 and B2. No differences were noted between groups A3 and B3 (all P>0.05). Necrosis of bone and marrow was observed in four control and three methylprednisolone-treated chickens (P>0.05). Significant new bone formation and fat cell proliferation in pubertal and young chickens occurred 12 to 19 weeks after administration of high-dose methylprednisolone. CONCLUSIONS: Younger animals may be more susceptible to methylprednisolone, and responses to methylprednisolone in femoral marrow may vary among individuals.

Early neuromechanical outcomes of the triceps surae muscle-tendon after an Achilles' tendon repair.

OBJECTIVES: To compare the neuromechanical and functional characteristics of the legs of athletes who underwent unilateral Achilles' tendon repair and their controls, and to determine any correlation between the characteristics. DESIGN: A case-control and cross-sectional study. SETTING: A university institute. PARTICIPANTS: Male athletes (N=33) were recruited; 23 in the ≥3- and <12-month postsurgical group (median age, 29.8y; age range, 21.9-40.0y) and 10 in the control group (median age, 30.0y; age range, 21.1-39.5y) who had not undergone any surgery. INTERVENTION: Surgical Achilles' tendon repair in the study group. MAIN OUTCOME MEASURES: Bilateral measurements of activation strategy involving the triceps surae and tibialis anterior muscles, mechanical properties of the Achilles' tendon, and explosive performance tests were conducted. RESULTS: Compared with the noninjured legs and the control legs, the repaired legs showed lower normalized rates of electromyographic rise (RER) in the soleus, gastrocnemius medialis, and gastrocnemius lateralis (P ranged between .006 and .001); and less tendon stiffness, greater hysteresis, and less rates of force development (RFD) (P ranged between .006 and <.001). Repaired legs had less ankle dorsiflexion, a shorter 1-leg hopping distance, and lower balance scores (P≤.001). The noninjured legs of the athletes who underwent surgical Achilles' tendon repair had a lower normalized RER (0-50 ms) in the soleus and lateral gastrocnemius when compared with the legs of the healthy controls (P=.011). The neuromechanical outcomes and explosive performances showed correlations with RFD, 1-leg hopping distance, and balance score. CONCLUSIONS: The athletes who underwent unilateral Achilles' tendon repair demonstrated bilateral neuromechanical deficits within the 1-year postsurgical period.

Comparison of quadriceps-sparing minimally invasive and medial parapatellar total knee arthroplasty: a 2-year follow-up study.

BACKGROUND/PURPOSE: Quadriceps-sparing minimally invasive total knee arthroplasty (TKA) has been proposed to limit surgical dissection without compromising surgical outcome. We conducted a prospective and randomized study to compare the outcomes of patients who underwent quadriceps-sparing TKA with the outcomes of those who underwent standard medial parapatellar TKA, after a 2-year follow-up period. METHODS: Eighty primary TKA procedures that were to be performed in 60 osteoarthritis patients were randomly assigned to either a quadriceps-sparing (40 knees) or a standard medial parapatellar (40 knees) group. All surgeries were designed to set the prosthesis with a femoral component alignment of 7° valgus and a tibial component alignment that was perpendicular to the tibial shaft. Surgical time and tourniquet time were recorded. Outcome variables included knee function, as defined by a hospital for special surgery knee score; quadriceps muscle strength, which was measured by an isokinetic dynamometer; pain, as indicated on a visual analog scale; prosthetic position, which was measured on plain radiograph; and range of motion. RESULTS: Patients who underwent the 38 quadriceps-sparing and 37 standard TKA procedures completed the 2-year follow-up period without any infection or revision. The mean surgical time and tourniquet time were significantly longer in the quadriceps-sparing group. The mean peak quadriceps muscle strength, hamstring muscle strength, normalized muscle balance (hamstring/quadriceps ratio), pain score, function score, and range of motion were comparable in both groups at 2 months and 2 years. In the quadriceps-sparing group, both the femoral and the tibial components were significantly more varus-deviated from the expected position. CONCLUSIONS: Patients undergoing quadriceps-sparing and standard medial parapatellar TKA had comparable outcomes for quadriceps muscle strength, hamstring-quadriceps balance, and knee function; however, the quadriceps-sparing TKA was more time consuming surgically and resulted in a less accurate prosthesis position.

Differences between chondrocytes and bone marrow-derived chondrogenic cells.

Implantation of autologous chondrogenic cells has become the mainstay strategy for repairing articular cartilage defects. Because the availability of autologous chondrocytes is extremely limited, many recent studies have used artificially induced mesenchymal stem cells (iMSCs) as substitutes for chondrocytes. In this study, we analyzed the differences between the iMSCs and chondrocytes, including their molecular biological and mechanical properties. Human bone marrow-derived MSCs were collected and induced to exhibit the chondrogenic phenotype by culturing the pelleted MSCs in a chemically defined culture medium supplemented with transforming growth factor-beta 1. The molecular biological properties of iMSCs and culture-expanded chondrocytes, including their mRNA profiles and surface proteomics, were analyzed using reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry, respectively. The biomechanical properties of iMSCs and native chondrocytes, including their surface topology, adhesion force, and membrane stiffness, were analyzed using atomic force microscopy (AFM). Both iMSCs and chondrocytes presented type II collagen and glycosaminoglycan, whereas only chondrocytes presented type X collagen. Flow cytometric assays showed that the expression of type II collagen and integrin-1 was higher in the chondrocytes than in the iMSCs. AFM revealed that the MSCs, iMSCs, and chondrocytes greatly differed in their shape. The MSCs were spindle shaped and easily distinguishable from the spherical chondrocytes. The iMSCs appeared round and resembled the spherical chondrocytes; however, the iMSCs were flatter with a central hump of condensed mass and a surrounding thin and broad pleat. The mean adhesion force and mean surface stiffness were significantly lower for the iMSCs (4.54 nN and 0.109 N/m, respectively) than for the chondrocytes (6.86 nN and 0.134 N/m, respectively). To conclude, although the iMSCs exhibited the chondrogenic phenotype, they differed from the chondrocytes in their molecular biological and mechanical properties.

Risk factors for hip fracture sites and mortality in older adults.

BACKGROUND: Our study was designed to (1) investigate the risk factors associated with cervical or trochanteric hip fractures; and (2) identify the risk factors for increased mortality in the elderly population sustaining hip fractures, after adjusting the miscellaneous baseline prefracture conditions. METHODS: Two hundred seventeen elder patients with first-time, low-trauma hip fractures were enrolled. The follow-up time ranged from 35 months to 56 months. Potential risk factors for hip fracture types included (1) the 77 items on the self-reported questionnaire; (2) the body height, weight, and body mass index; (3) tests of coordination, handgrip strength, and peak expiratory flow rate; and (4) the bone mineral density variables. GTFN ratio was defined as the bone mineral density ratio between the greater trochanter and the femoral neck. Multivariate logistic regression and Cox regression models were used for analysis. The population attributable risk proportion of death to each significant factor was estimated. RESULTS: Risk factors for trochanteric fractures include a GTFN ratio ≤0.81, being male, and an age >80 years. Risk factors for higher mortality after hip fracture included trochanteric fracture, body mass index ≤20 (kg/m), poor self-assessed health status, peak expiratory flow rate ≤215 (L/min), being male, illiteracy, and coordination abnormality, in the declining order of population attributable risk proportion. Trochanteric fractures had a significantly higher cumulative mortality at 36 months, 48 months, and 60 months than cervical fractures. CONCLUSIONS: The novel GTFN ratio was associated with hip fracture sites. Clinically, cervical and trochanteric fractures represent different disease entities because of the difference in their mortality rates.

Relationship of idiopathic osteonecrosis of the femoral head to perfusion changes in the proximal femur by dynamic contrast-enhanced MRI.

OBJECTIVE: The purpose of this article is to relate intramedullary perfusion of the proximal femur to severity of osteonecrosis of the femoral head by using dynamic contrast-enhanced MRI (DCE-MRI). SUBJECTS AND METHODS: Twelve patients (14 symptomatic hips) who underwent DCE-MRI and had subsequent core decompression of the femoral head were examined. Hips were graded for severity according to MRI findings and were assigned scores of 0 (negative findings), 1 (focal marrow abnormalities), and 2 (subchondral collapse). Thirteen asymptomatic hips acted as controls. The DCE-MRI data were analyzed by use of a pharmacokinetic two-compartment model. RESULTS: Compared with control hips, there was significantly greater peak enhancement in the femoral head in hips of all grades (p < 0.001) and in the femoral neck (p = 0.001) and intertrochanteric area (p = 0.001) in grade 2 hips. The time to peak was significantly delayed in the femoral head in grade 0 hips (p = 0.02) and in the intertrochanteric area in grade 2 hips (p = 0.003) compared with the controls. CONCLUSION: As evaluated by DCE-MRI, intramedullary peak enhancement in the femoral head increased with progression of idiopathic osteonecrosis of the femoral head, whereas there was delayed peak enhancement in the femoral head in hips with negative findings and intertrochanteric stasis in advanced osteonecrosis of the femoral head. Such perfusion changes as shown on MRI can occur with early osteonecrosis in the absence of other MRI abnormalities.

Immediate effect and predictors of effectiveness of taping for patellofemoral pain syndrome: a prospective cohort study.

BACKGROUND: Taping has been used to treat patellofemoral pain syndrome for more than 20 years, but its effectiveness is still controversial. PURPOSE: This study was undertaken to investigate the effect and predictors of effectiveness of taping in the treatment of patellofemoral pain syndrome. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 118 consecutive patients with patellofemoral pain syndrome were recruited; 100 of them completed this study. Patient sex, age, body mass index, Q angle, lateral patellar displacement, and lateral patellofemoral angle were recorded/measured. One therapist applied adhesive tape to each patient by the McConnell method. Patients scored their pain level on a 100-mm visual analog scale during stepping down from an 8-in platform, before and after taping. The change of score was evaluated by paired t test. Patients with a visual analog scale score decrease of 20 mm or more after taping were considered responsive, and the others were considered nonresponsive. The influences of the aforementioned factors, plus pretaping visual analog scale score, on the effectiveness of taping were analyzed by multivariate logistic regression. RESULTS: The overall mean visual analog scale score decreased significantly after taping (from 49.0 to 29.3 mm; P < .001). There were 66 patients in the responsive group and 34 in nonresponsive group. Among the factors, body mass index, lateral patellofemoral angle, and Q angle were significant predictors of effectiveness. The responsive group had significantly smaller mean lateral patellofemoral angle, larger mean Q angle, and larger mean pretaping visual analog scale score than the nonresponsive group. CONCLUSION: Taping was an effective treatment for patellofemoral pain syndrome, but was less effective in patients with higher body mass index, larger lateral patellofemoral angle, and smaller Q angle.

Comparison of articular cartilage repair by autologous chondrocytes with and without in vitro cultivation.

OBJECTIVE: autologous chondrocyte implantation usually requires in vitro cell expansion before implantation. We compared the efficacy of cartilage regeneration by in vitro-expanded chondrocytes at high density and freshly harvested chondrocytes at low density. DESIGN: surgically created osteochondral defects at weight-bearing surface of femoral condyles of domestic pigs were repaired by biphasic cylindrical porous plugs of DL-poly-lactide-co-glycolide and beta-tricalcium phosphate. Plugs were seeded with autologous chondrocytes in its chondral phase, and press-fit to defects. Seeded cells were (1) in vitro-expanded chondrocytes harvested from stifle joint 3 weeks before implantation and (2) freshly harvested chondrocytes from recipient knee. Seeding densities were 70 x 10(6) and 7 x 10(6) cells/mL, respectively. Cell-free plugs served as control and defects remained untreated as null control. Outcome was examined at 6 months with International Cartilage Repair Society Scale. RESULTS: the two experimental groups were repaired by hyaline cartilage with collagen type II and Safranin-O. Tissue in control group was primarily fibrocartilage. No regeneration was found in null control. Experimental groups had higher mean International Cartilage Repair Society scores than control in surface, matrix, and cell distribution, but were comparable with control in cell viability, subchondral bone, and mineralization. No significant difference existed between two experimental groups in any of the six categories. Uni-axial indentation test revealed similar creeping stress-relaxation property as native cartilage on experimental, but not control, specimen. CONCLUSIONS: cartilage could regenerate in both experimental models, in comparable quality. Culture of chondrocytes before implantation is not necessary.