Sang-Min Kim

The comparative efficacies of intra-articular and IV tranexamic acid for reducing blood loss during total knee arthroplasty

PurposeReduction in blood loss during surgery stabilizes hemodynamic status and aids in recovery after total knee arthroplasty (TKA). In this study, the authors examined whether different administration routes of tranexamic acid (TNA) might affect the amount of blood loss after TKA.MethodsA total of 150 patients were prospectively allocated to each of the three groups (intravenous, intra-articular, and placebo group) and underwent unilateral TKA. During closing the operative wound, TNA (1.5xa0g mixed in 100xa0cc of saline) was administered intravenously or intra-articularly according to the enrolled group, and an equivalent volume of normal saline was administered into the knee joint cavity and intravenously in the placebo group, respectively. The amount of blood loss and transfusion, and changes in haemoglobin levels were documented accordingly.ResultsThe mean blood loss in the intravenous, intra-articular, and placebo groups were 528xa0±xa0227, 426xa0±xa0197, and 833xa0±xa0412xa0ml, respectively. About 66xa0% (intravenous), 80xa0% (intra-articular), and 6xa0% (placebo) of each group did not require transfusion for any reason, and the mean amount of transfusion was 273.6, 129.6, and 920.8xa0ml, respectively. Preoperative haemoglobin values decreased by 1.6xa0±xa00.8, 1.8xa0±xa00.8, and 2.0xa0±xa00.9xa0mg/dl, respectively.ConclusionCompared to intravenous administration, intra-articular administration of TNA seems to be more effective in terms of reducing blood loss and transfusion frequency. TNA may improve the general conditions of patients given TKA by maintaining a hemodynamically stable state, aiding in recovery, and reducing the chance of transfusion-associated side effects and complications.Level of evidenceII.

Arthroscopic treatment for impingement of the anterolateral soft tissues of the ankle

We treated 52 patients with impingement of the anterolateral soft tissues of the ankle by arthroscopic debridement. All had a history of single or multiple inversion injuries, without instability. One half had negative stress radiographs (stable group), while the others were positive (unstable group). Their mean age was 31 years and there were 35 men and 17 women. The results were assessed at a mean follow-up of 30 months. Three patients (6%) had a fair result, while 49 (94%) had an excellent or good outcome. No difference was found in the final results between the two groups (p > 0.05). We conclude that anterolateral impingement of the ankle should be considered in a patient with chronic anterolateral pain after an injury, regardless of the stability of the ankle.

Prediction of survival, second fracture, and functional recovery following the first hip fracture surgery in elderly patients

This study was designed to investigate predictable factors of mortality, second fracture, and functional recovery within 24 months of hip fracture surgery in elderly patients. In addition, the authors sought to identify differences in survival and functional outcomes according to fracture type. Four hundred and fifteen patients with acute, first-time and lower-energy trauma hip fractures were enrolled into this prospective cohort study and followed for a minimum of 24 months. The potential risk factors of mortality and functional outcomes considered were; (1) age, gender, body mass index, previous fracture history, preoperative ambulatory ability and residency type; (2) 8 comorbidity items, cognitive impairment, smoking, and American Society of Anesthesiologists classification; and (3) delay prior to surgery, fracture type, operation time, operation method, and postoperative fall history. Multivariate logistic regression and Cox regression models were used for analysis. One-year and 2-year mortality rates after hip fracture surgery were 14.7% and 24.3%, respectively. The 2-year second fracture rate was 9.2% and the 2-year functional recovery rate was 38.6%. Advanced age, cancer, a prior fracture history, and a solitary life were found to be significantly associated with the risk of increased 2-year mortality. A fall within 1 year of surgery and a solitary life were found to be closely associated with the risk of a second fracture, and malignancy and cognitive impairment with a poor functional outcome. Operation time and the 2-year second fracture rate differed significantly between the two fracture groups. An understanding of the incidences and risk factors of mortality and postoperative outcomes following hip fracture surgery in elderly patients provides a valuable basis to improve in health care of geriatric population.

Cementless Modular Total Hip Arthroplasty in Patients Younger than Fifty with Femoral Head Osteonecrosis: Minimum Fifteen-Year Follow-Up

This study aimed to report the outcome of total hip arthroplasty (THA) with a modular femoral component in patients younger than fifty years with osteonecrosis of femoral head. Sixty-four osteonecrotic hips in fifty-five patients were available for clinical and radiographic analyses at minimum follow-up of fifteen-years. The mean Harris hip score improved from 36 points preoperatively to 92.7 points at final follow-up. Sixty-two (95.3%) hips demonstrated stable bone ingrowth. No hips showed loosening or required revision for aseptic loosening. Survivorship with an end point of stem revision for any reason was 93.8% and for aseptic loosening was 100% at 16.8years. We believe that cementless THA with a modular stem is a promising procedure for young and active patients with osteonecrosis of the femoral head.

Mechanical axis-derived femoral component rotation in extramedullary total knee arthroplasty: a comparison between femoral transverse axis and transepicondylar axis

PurposeCorrect rotational alignment of the femoral component is paramount to the success of total knee arthroplasty, but debate continues as to which method is the most reliable. The purpose of this study was to evaluate mechanical axis-derived rotational axis of the femoral component using an extramedullary femoral alignment guide system.MethodsBetween 2009 and 2010, 60 patients (120 knees) underwent simultaneous bilateral total knee arthroplasty. Postoperative CT scans were performed on all 120 knees. The mechanical axis-derived rotational axis of the femoral component was compared with the surgical transepicondylar axis on CT scans.ResultsThe femoral component was externally rotated compared with the surgical transepicondylar axis (meanxa0=xa01.6°, SDxa0=xa02.2°, range: from 4.8° of internal rotation to 7.9° of external rotation). One hundred and nine of the 120 knees (90.8%) were rotated by less than 5° from the surgical transepicondylar axis. All inter-observer observations on CT scans were within a range of ±2.1° and showed no significant differences.ConclusionMechanical axis-derived rotational axis of the femoral component was found to be closely related to the surgical transepicondylar axis, to an extent which suggests that the mechanical axis-derived rotational axis could be a new alternative option in determining optimal rotational alignment of the femoral component during total knee arthroplasty.Level of evidenceII.

ERK5 regulates invasiveness of osteosarcoma by inducing MMP‐9

The purpose of this study is to determine the role of ERK5 in cellular invasion of osteosarcoma (OS). The human OS cell line (MG63, SaOS, and U2OS) and primary OS cells were used for the study. The expression of ERK5 and MMP‐9 in each cell was examined by western blot or RT‐PCR. To evaluate the biological role of ERK5, proliferation assay (MTT) and invasion assay (BD Matrigel™) were performed after silencing ERK5 using siRNA. MMPs expressions were analyzed using RT‐PCR and zymography after silencing ERK5. ERK5 was distinctly overexpressed in U2OS and primary OS cell. Both of them also expressed MMP‐9, which was not shown in MG63 and SaOS in RT‐PCR. ERK5 silencing did not suppress the proliferation of OS cells. However, ERK5 silencing significantly reduced the number of invading cells in invasion assay. The expression of MMP‐9 was specifically reduced after silencing ERK5. The zymography showed that the enzyme activity of MMP‐9 was also reduced after ERK5 suppression. The expression of ERK5 regulates the invasion of OS cells by inducing MMP‐9 expression. Therefore, ERK5 may be a new therapeutic target in invasive OS expressing MMP‐9.

An alternative method to create extramedullary references in total knee arthroplasty

PurposeHistorically, extramedullary techniques have focused on finding the femoral head center and referred mainly to the anterosuperior iliac spine (the FHC method) in total knee arthroplasty (TKA). The purpose of this study was to evaluate a new extramedullary alignment system that uses neutral overall limb mechanical alignment as an extramedullary reference (the MA method).MethodsA retrospective review of 1018 TKAs (508 FHC group, 510 MA group) was performed to compare the radiographic results obtained using these two methods. There were 75 male patients and 577 female patients with varus osteoarthritis of the knee. Limb and prosthesis alignments in the coronal plane were investigated at 2xa0months after surgery.ResultsThe accuracies of postoperative alignments of implanted prostheses were better in the MA group than in the FHC group, as assessed by (1) overall limb alignment (MA group, varus 1.4°xa0±xa02.7°; FHC group, varus 2.2°xa0±xa02.9°), and (2) femoral component coronal alignment (MA group, 89.4°xa0±xa02.3°; FHC group, 88.0°xa0±xa02.7°). Overall limb alignment was within 0°xa0±xa05° of the mechanical axis in 96.1% of the MA group and in 86.6% of the FHC group. Mean femoral component medial angle was within 0°xa0±xa05° in 98.4% of the MA group and in 92.5% of the FHC group.ConclusionThe accuracies of the postoperative radiographic alignments of implanted prostheses were found to be improved when the mechanical axis of the overall lower limb was used as an extramedullary reference. This new reference system would help to achieve correct limb and prostheses alignments during TKA.Level of evidenceIII.

Comparison of manual rasping and robotic milling for short metaphyseal-fitting stem implantation in total hip arthroplasty: a cadaveric study.

Objective: The ROBODOC system offers the theoretical advantage of providing better fit and mechanical stability of the stem in total hip arthroplasty. However, there has been no previous study on short metaphyseal-fitting stem implantation using the ROBODOC system. The aim of the present study was to compare the implant position and primary stability of short metaphyseal-fitting stems implanted by robotic milling and manual rasping in a human cadaveric femoral model. Methods: Eight matched pairs of human cadaveric femora were randomly assigned to a robotic milling group or manual rasping group. Operative time and intraoperative femoral fractures were monitored, and radiographic evaluation of stem alignment was performed by comparison of preoperative planning and postoperative CT data. Stability testing was performed on six matched pairs of femora, excluding two specimens in which intraoperative fractures occurred. Results: The robotic milling procedures took an average of 27 minutes longer than the manual rasping procedures (pu2009<u20090.001). The robotic milling group exhibited significantly better anteroposterior alignment and vertical seating, and also showed a significantly reduced variability in both alignment and vertical seating. No intraoperative femoral fracture was detected in the robotic milling group, whereas two femoral fractures and one femoral stem tip perforation were detected in the manual rasping group. Stability testing showed no significant difference in translational and rotational migrations between the two groups, although the robotic milling group showed a trend towards reduced variability of stability. Conclusions: Our cadaveric study suggests that the use of the ROBODOC system for short metaphyseal-fitting stem implantation may have advantages in improving implant fit and reducing the risk of intraoperative femoral fractures without compromising primary stability.

Current Role and Application of Teriparatide in Fracture Healing of Osteoporotic Patients: A Systematic Review

Background The use of osteoanabolic agents to facilitate fracture healing has been of heightened interest to the field of orthopaedic trauma. This study aimed to evaluate the evidence of teriparatide for fracture healing and functional recovery in osteoporotic patients. Methods We performed a literature search in PubMed, EMBASE, Web of Science, and the Cochrane Library using terms including “Fracture” [tiab] AND “Teriparatide [tiab] OR “PTH” [tiab]. Results This systematic review included 6 randomized clinical trials, 4 well-controlled retrospective studies, and 1 retrospective post hoc subgroup analysis. Fracture location was 2 in pelvis, 3 in proximal femur, 1 in distal femur, 1 in shoulder, 2 in wrist and 2 in spine. The use of teriparatide yielded positive effects on radiographic bone healing in 6 studies, but was not associated with better radiographic outcome in 3. In terms of functional recovery, teriparatide injection was related with decrease in pain or shorter time to mobilization in 6 studies, but not related with pain numerical scale and mobility in 3. Conclusions Our findings suggest that teriparatide provide selective advantages to fracture healing or functional recovery in the management of osteoporotic fractures. A better understanding of the role of teriparatide on osteoporotic fractures requires greater evidences from large volume prospective trials.

Incidence and Factors Predicting Venous Thromboembolism After Surgical Treatment of Fractures Below the Hip.

Objectives: This study was designed to investigate the incidence and risk factors of postoperative venous thromboembolism (VTE) in a series of patients with fractures below the hip. In addition, we sought to examine the rates of VTE before and after introduction of thromboprophylaxis. Design: Retrospective review. Setting: University-based academic medical center. Patients: Nine hundred one consecutive patients met the inclusion criteria. Of the 901 patients, 337 (37.4%) were treated before the initiation of institutional guidelines for thromboprophylaxis and 564 (62.6%) received thromboprophylaxis in accordance with our hospitalization protocol. Intervention: Surgical intervention for fractures occurring in the lower extremity below the hip. Main Outcome Measurements: Symptomatic thromboembolic events within 90 days of surgery and risk factors of postoperative VTE. Results: Of the 901 patients, 25 (2.7%) had confirmed symptomatic deep vein thrombosis and 13 (1.4%) had symptomatic pulmonary embolism. The overall incidence of symptomatic VTE was significantly different between the patients not receiving thromboprophylaxis (6.8%; 23 of 337) and those receiving thromboprophylaxis (2.3%; 13 of 564). Of the 31 variables tested for an association with VTE, an advanced age of more than 60 years, cardiovascular disease, and chronic lung disease were independent risk factors. Conclusions: Clinically detectable VTE in fractures of the lower extremity below the hip are not uncommon, and thromboprophylaxis seemed to decrease the incidence of postoperative VTE. Level of Evidence: Prognostic Level II. See the guidelines for authors for a complete description of levels of evidence.