Recently, technologies to culture one or more cell types in three dimensions have attracted a great deal of attention in tissue engineering. Particularly, the improved viability, self-renewal capacity, and differentiation potential have been reported for stem cell spheroids. However, it is crucial to modulate spheroid functions with instructive signals to use multi-cellular spheroids in tissue engineering. We have been developing ECM-mimicking fibrous materials decorated with cell-instructive cues, which were incorporated within 3D stem cell spheroids to fine-tune their functions as modular building blocks for bottom-up tissue-engineering applications. In particular, we created composite spheroids of human adipose-derived stem cells (hADSCs) incorporating nanofibers coated with instructive signal of either transforming growth factor-β3 or bone morphogenetic growth factor-2 for chondrogenesis or osteogenesis of stem cells, respectively. The bilayer structure of osteochondral tissue was subsequently mimicked by cultivating each type of spheroid inside 3D-printed construct. The in vitro chondrogenic or osteogenic differentiation of hADSCs within the biphasic construct under general media was locally regulated by each inductive component. More importantly, hADSCs from each spheroid proliferated and sprouted to form the integrated tissue with interface of bone and cartilage tissue. This approach may be applied to engineer complex tissue with hierarchically organized structure.
It is undetermined which factors predict return to work following arthroscopic rotator cuff repair. We aimed to identify which factors predicted return to work at any level, and return to pre-injury levels of work 6 months post-arthroscopic rotator cuff repair. Multiple logistic regression analysis of prospectively collected demographic, pre-injury, preoperative, and intraoperative data from 1502 consecutive primary arthroscopic rotator cuff repairs, performed by a single surgeon, was performed to identify independent predictors of return to work, and return to pre-injury levels of work respectively, 6 months post-surgery. Six months post-rotator cuff repair, 76% of patients returned to work (RTW), and 40% returned to pre-injury levels of work (Full-RTW). RTW at 6 months was likely if patients were still working after their injuries, but prior to surgery (Wald statistic [W]=55, p<0.0001), were stronger in internal rotation preoperatively (W=8, p=0.004), had full-thickness tears (W=9, p=0.002), and were female (W=5, p=0.030). Patients who achieved Full-RTW were likely to have worked less strenuously pre-injury (W=173, p<0.0001), worked more strenuously post-injury but pre-surgery (W=22, p<0.0001), had greater behind-the-back lift-off strength preoperatively (W=8, p=0.004), and had less passive external rotation range of motion preoperatively (W=5, p=0.034). Patients who were still working post-injury, but pre-surgery were 1.6-times more likely to RTW than patients who were not (p<0.0001). Patients who nominated their pre-injury level of work as “light” were 11-times more likely to achieve Full-RTW than those who nominated “strenuous” (p<0.0001). Six months post-rotator cuff repair, a higher patient-rated post-injury, but pre-surgery level of work was the strongest predictor of RTW. A lower patient-rated pre-injury level of work was the strongest predictor of Full-RTW. Greater preoperative subscapularis strength independently predicted both RTW, and Full-RTW.
The aim of this study was to investigate the biomechanical effect of the anterolateral ligament (ALL), anterior cruciate ligament (ACL), or both ALL and ACL on kinematics under dynamic loading conditions using dynamic simulation subject-specific knee models. Five subject-specific musculoskeletal models were validated with computationally predicted muscle activation, electromyography data, and previous experimental data to analyze effects of the ALL and ACL on knee kinematics under gait and squat loading conditions.Objectives
Methods
The role of unicompartmental knee arthroplasty (UKA) in spontaneous osteonecrosis of the knee (SONK) remains controversial, even though SONK usually involves only medial compartment of the knee joint. We aimed to compare the survival rate and clinical outcomes of UKA in SONK and medial compartment osteoarthritis (MOA) via a meta-analysis of previous studies. MEDLINE database in PubMed, the Embase database, and the Cochrane Library were searched up to January 2018 with keywords related to SONK and UKA. Studies were selected with predetermined inclusion criteria: (1) medial UKA as the primary procedure, (2) reporting implant survival or clinical outcomes of osteonecrosis and osteoarthritis, and (3) follow-up period greater than 1 year. Quality assessment was performed using the risk of bias assessment tool for non-randomised studies (RoBANs). A random effects model was used to estimate the pooled relative risk (RR) and standardised mean difference. The incidence of UKA revision for any reason was significantly higher in SONK than in MOA group (pooled RR = 1.83, p = 0.009). However, the risk of revision due to aseptic loosening and all- cause re-operation was not significantly different between the groups. Moreover, when stratified by the study quality, high quality studies showed similar risk of overall revision in SONK and MOA (p = 0.71). Subgroup analysis revealed worse survival of SONK, mainly related to high failure after uncemented UKA. Clinical outcomes after UKA were similar between SONK and MOA (p = 0.66). Cemented UKA has similar survival and clinical outcomes in SONK and MOA. Prospective studies designed specifically to compare the UKA outcomes in SONK and MOA are necessary.
Occasionally, patients experience new or increased ankle pain following total knee arthroplasty (TKA). The aims of this study were to determine (1) how the correction of varus malalignment of the lower limb following TKA affected changes in alignment of the ankle and hindfoot, (2) the difference in changes in alignment of the ankle and hindfoot between patients with and without ankle osteoarthritis (OA), and (3) whether the rate of ankle pain and the clinical outcome following TKA differed between the 2 groups. We retrospectively reviewed prospectively collected data of 56 patients (99 knees) treated with TKA. Among these cases, concomitant ankle OA was found in 24 ankles. Radiographic parameters of lower-limb, ankle, and hindfoot alignment were measured preoperatively and 2 years postoperatively. In addition, ankle pain and clinical outcome 2 years after TKA were compared between patients with and without ankle OA.Background
Methods
Authors sought to determine the degree of lateral condylar hypoplasia of distal femur was related to degree of valgus malalignment of lower extremity in patients who underwent TKA. Authors also examined the relationships between degree of valgus malalignment and degree of femoral anteversion or tibial torsion. This retrospective study included 211 patients (422 lower extremities). Alignment of lower extremity was determined using mechanical tibiofemoral angle (mTFA) measured from standing full-limb AP radiography. mTFA was described positive value when it was valgus. Patients were divided into three groups by mTFA; more than 3 degrees of valgus (valgus group, n = 31), between 3 degrees of valgus to 3 degrees of varus (neutral group, n = 78), and more than 3 degrees of varus (varus group, n = 313). Condylar twisting angle (CTA) was used to measure degree of the lateral femoral condylar hypoplasia. CTA was defined as the angle between clinical transepicondylar axis (TEA) and posterior condylar axis (PCA). Femoral anteversion was measured by two methods. One was the angle formed between the line intersecting femoral neck and the PCA (pFeAV). The other was the angle formed between the line intersecting femoral neck and clinical TEA (tFeAV). Tibial torsion was defined as a degree of torsion of distal tibia relative to proximal tibia. It was determined by the angle formed between the line connecting posterior cortices of proximal tibial condyles and the line connecting the most prominent points of lateral and medial malleolus. Positive values represented relative external rotation. Negative values represented relative internal rotation.Background
Methods
Recently, concerns arose over the medial tibial bone resorption of a novel cobalt-chromium (CoCr) implant. This study aimed to investigate the effects of tibial component material, design, and patient factors on periprosthetic bone resorption and to determine its association with clinical outcomes after total knee arthroplasty (TKA). A total of 462 primary TKAs using five types of implants were included. To evaluate tibial periprosthetic bone resorption, we assessed radiolucent lines (RLL) and change in bone mineral density at the medial tibial condyle (BMDMT). Factors related to bone resorption were assessed using regression analysis. Clinical outcomes were also evaluated with respect to periprosthetic bone resorption. Compared to titanium (Ti) implants, CoCr implants showed a higher incidence of complete RLL (23.1% vs. 7.9% at two years post-TKA) and a greater degree of BMDMT reduction. However, there was no significant difference between the implants made of the same material. Increased medial tibial bone resorption was associated with male sex, osteoporosis, larger preoperative varus deformity, longer follow-up period, and lower body mass index. The periprosthetic bone resorption was not associated with clinical outcomes including changes in range of motion and WOMAC score. Furthermore, no cases warranted additional surgery. Periprosthetic bone resorption was associated with implant material but not with implant design. Moreover, patient factors were related to the medial tibial bone resorption post-TKA. However, the periprosthetic bone resorption was not associated with short-term clinical outcomes. We contend that researchers should incorporate integrative considerations when developing and assessing novel implants.
We sought to determine whether there was a difference in the posterior condylar offset (PCO), posterior condylar offset ratio (PCOR) following total knee arthroplasty (TKA) with anterior referencing (AR) or posterior referencing (PR) systems. We also assessed whether the PCO and PCOR changes, as well as patient factors were related to range of motion (ROM) in each referencing system. In addition, we examined whether the improvements in clinical outcomes differed between the two referencing systems. This retrospective study included 130 consecutive patients (184 knees) with osteoarthritis who underwent primary posterior cruciate ligament (PCL)-substituting fixed-bearing TKA. All patients were categorized into the AR or PR group according to the referencing system used. Radiographic parameters, including PCO and PCOR, were measured using true lateral radiographs. The difference between preoperative and postoperative PCO and PCOR values were calculated. Clinical outcomes including ROM and Western Ontario and McMaster University (WOMAC) scores were evaluated preoperatively and at 2 years after TKA. The PCO, PCOR values, and clinical outcomes were compared between the two groups. Furthermore, multiple linear regression analysis was performed to determine the factors related to postoperative ROM in each referencing system.Purpose
Methods
Laser-engineered net shaping (LENS) of coated surfaces can overcome the limitations of conventional coating technologies. We compared the The Objectives
Methods
Many studies have found associations between laboratory biomarkers and periprosthetic joint infection (PJI), but it remains unclear whether these biomarkers are clinically useful in ruling out PJI. This meta-analysis compared the performance of interleukin-6 (IL-6) versus procalcitonin (PCT) for the diagnosis of PJI. In this meta-analysis, we reviewed studies that evaluated IL-6 or/and PCT as a diagnostic biomarker for PJI and provided sufficient data to permit sensitivity and specificity analyses for each test. The major databases MEDLINE, EMBASE, the Cochrane Library, Web of Science, and SCOPUS were searched for appropriate studies from the earliest available date of indexing through February 28, 2017. No restrictions were placed on language of publication.Purpose
Materials and Methods
As the number of primary or revision TKA with stem extension cases are growing simultaneously, the number of periprosthetic fracture in these cases has also increased accordingly. However, there have been few reports on the classification and treatment of periprosthetic fracture following stemmed TKA and lack of information about the treatment outcome. The purposes of this study were 1) to demonstrate classification and management of periprosthetic fractures after stemmed TKA and 2) to report treatment outcome after the periprosthetic fractures. This retrospective study included 17 knees (15 patients) with an average age of 69.7 years. All cases were revision TKA cases, and there were 13 female and 2 male patients. The patients were treated nonoperatively or underwent operation by orthopedic principle. The period of union was evaluated by confirming the formation of callus crossing fragments in radiographs. We reviewed the complications and functional outcomes after treatment of periprosthetic fracture following revision TKA by assessing FF, FC and scoring WOMAC and KSS.Background
Materials and Methods
Joint line, patellar height and posterior condylar offset (PCO) are related to functional outcome such as stability and range of motion after revision total knee arthroplasty (TKA). The purpose of this study was (1) to determine whether revision TKA can restore the joint line, patella height and condylar offset after surgery, and (2) to assess factors associated with failed restoration. We retrospectively reviewed 27 consecutive patients who underwent revision TKA. Among 27 patients, 11 patients had two-stage revision TKA due to periprosthetic joint infection while 14 patients underwent revision TKA due to aseptic loosening. In addition, there were 2 patients who had traumatic event causing a periprosthetic fracture which led to revision TKA. The joint line was measured using the distance from the adductor tubercle of the femur to the most distal portion of the medial femoral component on knee anterior-posterior radiographs. Patella height was assessed using the Caton-Deschamps method. In addition, PCO were measured relative to the tangent of the posterior cortex of the femur using knee lateral radiograph. All parameters were compared between pre- and postoperative radiographs after revision TKA.Background
Materials and Methods
Osteonecrosis of the femoral head (ONFH) is a painful and disabling condition, which most commonly involves the hips of young patients. But despite of the high incidence, treatment is still has not been definitely identified. We performed a modified muscle pedicle bone graft (MPBG) technique using anterior one-third of gluteus medius (GM) attached to the greater trochanter (GT) in ONFH. The purpose of this study was to evaluate the effectiveness of our technique on ONFH in ARCO stage II and III patients. Between June 2007 and March 2015, 24 hips were treated by our technique, who were able to follow up at least 2 years. The group was consisted of 15 men and 8 women, mean age of 36 years at the time of surgery. Mean follow-up was 5 years. Twenty of 24 hips hips had no progression of necrotic lesions. The postoperative scintigrams showed increased blood flow in the 3 month follow up evaluation. But 4 hips underwent THA at the mean follow-up of 6 years after the surgery, and considered as “failure”. Excluding the 4 failed cases, the mean Harris hip score was improved from 54 points to 85 points at the last follow up. Through our new technique, we showed 83% of survival rate by average of 5 year follow up. And compared to other reports, our technique showed relatively good survival rate and clinical outcomes. Therefore, we suggest this modified technique as one of promising treatment of choices for young patients with ARCO stage II or III ONFH.
This meta-analysis was designed to compare the effectiveness and safety of intravenous (IV) versus topical administration of tranexamic acid (TXA) in patients undergoing primary total knee arthroplasty (TKA) by evaluating the need for allogenic blood transfusion, incidence of postoperative complications, volume of postoperative blood loss, and change in hemoglobin levels. Studies were included in this meta-analysis if they assessed the allogenic blood transfusion rate, postoperative complications including pulmonary thromboembolism (PTE) or deep vein thrombosis (DVT), volume of postoperative blood loss via drainage, estimated blood loss, total blood loss, and change in hemoglobin before and after surgery in primary TKA with TXA administered through both the intravenous (IV) and topical routes.[Fig. 1]Purpose
Materials and Methods
Recently, the combination of press-fit acetabular cup with ceramic articulation is a widely used for implanting cementless acetabular components and has been shown to provide good initial stability. However, these methods may lead to elevating stresses, changing in the bearing geometries, and increasing wear due to deformation of the cup and insert. In addition, there is a potential for failure of ceramic inserts when a large ball head was used because it should be assembled with shallow thickness of the acetabular cup. For risk reduction of it, we applied direct metal tooling (DMT) based on 3D printing for porous coating on the cup. Due to its capability of mechanical strength, DMT coated cup could be feasible to provide better stability than conventional coating. Therefore, we constructed laboratory models for deformation test simulating an press-fit situation with large ceramic ball head to evaluate stability of the DMT coated cup compared with conventional coated cup. The deformation test was performed according to the test setup described by Z. M. Jin et al. The under reaming of the cavity in a two-point pinching cavity models of polyurethane (PU) foam block (SAWBONES, Pacific Research Laboratories, USA) with a grade 30 were constructed. Titanium plasma spray (TPS) and direct metal tooling (DMT) coated acetabular cups (BENCOX Mirabo and Z Mirabo Cup, Corentec Co. Ltd., KOREA) with a 52 mm size (n=3, respectively) were used for the test. These cups were implanted into the PU foam blocks, and followed by impaction of the inserts (BIOLOX delta, Ceramtec, GE) with a 36/44 size (n=6) into the acetabupar cups as shown in Fig. 1. Roundness and inner diameter of the acetabular cups and inserts were measured using a coordinate measuring machine (BHN 305, Mitutoyo Neuss, GE) in three levels; E2, E3, and E4 (3, 5, and 7 mm below the front face, respectively). Also, these parameters of the acetabular cup were measured in two level; E1 and E5 (5 and 11 mm below the front face) as shown in Fig. 2. Changes in roundness and inner diameter of the cup and insert were measured to evaluate deformation in relation to porous coating on the acetabular cups.Introduction
Materials and Methods
To promote rapid bone healing, an adequate stable fixation implant with a percutaneous reduction instrument should be used for Vancouver type B1 or C fractures. The objective of this study was to describe radiographic and clinical outcomes of patients with periprosthetic fracture (PPF) around a stable femoral stem, treated with a distal femoral locking plate alone or with a cerclage cable. A total of 21 patients with PPF amenable to either a reverse distal femoral locking plate (LCP DF®) alone or with a cerclage cable, with a mean age of 75.7 years, were included. In these patients, 10 fractures were treated with a reverse LCP DF® alone and were classified as group I, and 11 additionally received a cerclage cable and were classified as group II.[Fig.1]Purpose
Materials and Methods
Cementless arthroplasty has been widely used for younger patients with osteoarthritis and other joint pathology. Cementless arthroplasty will be required to porous surface which is to similar to the trabecular bone for bone ingrowth. Titanium Plasma Spray (TPS) has been worldwide used for the porous coating method on arthroplasty. However, TPS coating is limited that would not to establish optimal porosity for bone ingrowth due to arbitary position of melted powder by plasma gas on substrate. Therefore, it is reported coating detached from its substrate (i.e. arthroplasty) is induced implant loosening. Thus, a novel Laser-aided Direct Metal Tooling (DMT) based on Additive Manufacturing (AM) was developed to overcome these limitations. In this study, we were done to assess stereological analysis, static tensile, shear, abrasion test, and physical analysis for evaluation of the efficacy of DMT which was newly-developed coating technology. Then, mechanical characteristics of DMT coating were compared to commercial TPS coating's. First, porosity of the DMT coating was evaluated using Microphotography and Scanning Electron Microscopy (SEM), as described in Figure 1. Static tensile and shear test for assessment of mechanical characteristic in relation to the DMT and TPS coating specimens were conducted on the basis of ASTM F1147 and F1044 using universal testing machine (Endolab®, Servohydraulic Test Frame, DE). Maximum tensile strength and maximum shear strength were evaluated for each specimen (n=5). Abrasion test was performed based on ASTM F1978 using Taber® Rotary Platform Abraser Model 5135 (TABER®Industries, USA). Abrasion losses for each specimen (n=6) were measured at 2, 5, 10, and 100 cycles, respectively.Introduction
Materials and Methods
A matched comparison was made between femoral neck-preserving short, tapered stems (n = 50) and conventional length femoral stems (n = 50) in cementless total hip arthroplasty between January 2008 and January 2012. Patients were matched for age, sex, body mass index, height, surgical approach, and surgeon. In group A, mean preoperative HHS and WOMAC scores of 55.0 and 53.0, respectively, improved to mean postoperative scores of 98.6 and 3.3, respectively, at an average follow–up of 37.2 months. In group B, mean preoperative HHS and WOMAC scores of 53.0 and 49.5, respectively, improved to mean postoperative scores 97.8 and 4.4, respectively, at an average follow–up of 35.3 months. In addition, no significant differences in mean postoperative HHS (
In this study, we investigated the long-term clinical results and survivorship of minimally invasive unicompartmental knee arthroplasty (UKA) by collecting cases that have been implanted for >10 years ago. Medial UKA on 180 cases in 142 patients was performed over a period of 1 year after the first introduction of minimally invasive UKA from January 2002 to December 2002. Among these, 166 cases in 128 patients who underwent Oxford phase 3 medial UKA using the minimally invasive surgery, with the exclusion of 14 cases including 10 cases of follow-up loss and 4 cases of death, were selected as the subject. The mean age of the patients at the time of surgery was 61 years, and the duration of the follow-up was minimum 10 years. All the preoperative diagnosis was osteoarthritis of the knee joint. Clinical and radiographic assessments were measured by the Knee Society clinical rating system, and the survival analysis was confirmed by the Kaplan–Meier method with 95% confidence interval (CI).Background
Methods
We prospectively analyzed 83 patients who underwent ceramic-on-ceramic THA using preassembled (n = 22) or modular acetabular components (n = 61) between June 2010 and June 2012. No radiographic evidence of progressive radiolucency, osteolytic lesions, acetabular fractures, or component migration was detected in either group. Furthermore, no patient required revision surgery for instability or ceramic breakage. Table 1 shows the mean postoperative HHS, WOMAC score, and acetabular component inclination and anteversion in groups A and B. No significant differences in mean postoperative HHS (P < 0.056), WOMAC score (P < 0.258), acetabular component inclination (P < 0.827), or anteversion (P < 0.549) were observed between the two groups according to the independent sample t-test. However, the chi-square (Fisher's exact) test showed a significant difference between the two groups with respect to the gender of the patients (P < 0.001, Table 2). These findings indicate that half of the women had smaller acetabular diameters accommodating a cup size of only 48–50-mm. Thus a preassembled ceramic liner is a very good option for women with a small acetabulum, which could permit the use of a larger femoral head (36-mm) with thin-walled acetabular components. In contrast, the component-specific complications between the two groups were quite similar. One patient (group B) had transient squeaking that disappeared after a few months. One patient (group B) had a mild limp caused by abductor muscle weakness, and one patient (group B) had a superficial wound infection that was treated with local debridement and antibiotics. Early dislocation (P < 0.488) occurred in three patients (one in group A and two in group B). Two patients (one in group A and one in group B) reported postoperative falling events at their bedside. The other in group B was a female with rheumatoid arthritis, which can lead to a much higher risk of dislocation due to soft tissue laxity around the hip joint. All of these patients were treated by closed reduction without further incident. Three patients (one in group A and two in group B) had mild iliopsoas pain (P < 0.488) that was not associated with loosening; however, the pain did not limit their activities (Table 3). In conclusion, we found no significant differences in the mean postoperative radiographic or functional outcomes or complications between the two groups, showing satisfactory performance at the 2 year follow up. Only the gender of the patient was significantly different between the two goups, demonstrating that a larger number of women had smaller acetabular diameters accommodating a cup size of only 48–50-mm. Although a preassembled cup with a 36-mm ceramic liner has proven safety in the short term, future research should focus on its long-term risks.
