Causes of Failure after Total Knee Arthroplasty in Osteoarthritis Patients 55 Years of Age or Younger

PURPOSE: To identify the modes of failure after total knee arthroplasty (TKA) in patients >55 years of age and to compare with those >55 years of age in patients who underwent revision TKA. MATERIALS AND METHODS: We retrospectively reviewed 256 revision TKAs among patients who underwent TKA for knee osteoarthritis between January 1992 and December 2012. The causes of TKA failure were analyzed and compared between the groups. RESULTS: Thirty-one revision TKAs were performed in patients 55 years of age at primary TKA. In the < or =55 years of age group, the most common cause of TKA failure was polyethylene wear (45%) followed by infection (26%) and loosening (17%). The interval from primary TKA to revision was 8.6 years (range, 1 to 17 years). There were relatively lower infection rate and higher loosening rate in patients < or =55 years of age, but the difference was not statistically significant. CONCLUSIONS: The main causes of failure after TKA in patients < or =55 years of age were polyethylene wear, infection and loosening, and there was no significant difference in the modes of failure after TKA between the two groups.

How to Calculate Sample Size and Why

WHY: Calculating the sample size is essential to reduce the cost of a study and to prove the hypothesis effectively. HOW: Referring to pilot studies and previous research studies, we can choose a proper hypothesis and simplify the studies by using a website or Microsoft Excel sheet that contains formulas for calculating sample size in the beginning stage of the study. MORE: There are numerous formulas for calculating the sample size for complicated statistics and studies, but most studies can use basic calculating methods for sample size calculation.

Co-development of autoimmune hepatitis and Sjogren's syndrome triggered by the administration of herbal medicines

Autoimmune hepatitis (AIH) has been reported in association with Sjogren's syndrome (SS). Drug-induced AIH has been rarely reported. A rare case of the co-development of AIH and SS in a 53-year-old woman after the consumption of herbal medicines is described. After admission, the patient complained of dryness in her mouth, and she was subsequently diagnosed with SS, which had not been detected previously. The patient's bilirubin and aminotransferase levels initially decreased following conservative management; however, they later began to progressively increase. A diagnosis of AIH was made based on the scoring system proposed by the International Autoimmune Hepatitis Group. The patient was administered a combination of prednisolone and azathioprine, and the results of follow-up liver-function tests were found to be within the normal range. This is an unusual case of AIH and SS triggered simultaneously by the administration of herbal medicines.

Cementless Total Hip Arthroplasty with Fourth Generation Ceramic-on-Ceramic Articulation: Minimum Two Years of Follow-up / 대한고관절학회지

PURPOSE: The purpose of this study is to report clinical and radiographic results over a period of two 2 years after cementless total hip arthroplasty (THA) with fourth generation ceramic-on-ceramic articulation. MATERIALS AND METHODS: We studied 22 patients, 23 cases which were followed up for two years among 25 patients, 26 patients who underwent cementless THA with the fourth generation ceramic between April 2009 and December 2009. The average age of the patients was 55.9 years old(22 to 72 years old), and the average follow-up duration was 28 months(24 to 32 months). A clinical evaluation was performed using the Harris hip score (HHS), and radiologic evaluation was based on acetabular cups and osteolysis of the femoral stems, instability, distance, angle, and so on. RESULTS: HHS showed an increase, from 54 for before-surgical treatment, to 91 at the last follow-up. Inguinal pain was observed in one case, and femoral pain was observed in two cases. Stable fixation was achieved in all cases, and no instability, osteolysis, or movement of acetabular cups and femoral stems was observed. CONCLUSION: Clinical and radiological short-term results for use ofthe fourth generation ceramic-on-ceramic cementless THA have favorable so far. Further follow-up study should be performed for evaluation of the long-term results.

Two Cases of Hyponatremia Induced by Duloxetine for Treating Peripheral Neuropathic Pain / 대한내과학회지

Duloxetine is a balanced serotonin and norepinephrine reuptake inhibitor available for treating peripheral neuropathic pain. The occurrence of hyponatremia as an adverse event of duloxetine treatment, but it has not yet been reported in Korea. Here, we report two cases of hyponatremia induced by duloxetine for treatment of peripheral neuropathic pain. Our findings highlight the need for special attention when using duloxetine in elderly patients taking thiazide diuretics.

Study on the Removal of Segmentally Broken Interlocking Screw in Intramedullary Nail / 대한정형외과연구학회지

In the literature, it is extremely difficult and takes long time to remove middle part of segmentally broken screws using ball-tip guide and extraction hook after femoral interlocking intramedullary nailing. Proximal part of broken locked screw can be removed with screwdriver easily, but it is very difficult to remove distal and especially middle part of broken screw which are usually angulated and should be removed to avoid interference with further procedure and complications. So we designed a technique for removal of segmentally broken distal locked screw which can be removed after withdrawal of nail proximally to realign screw segments and then actually applied this method to real case with short operative time and satisfactory outcome.

Renal Replacement Therapies on the Outcomes of Acute Renal Failure Patients in ICU / 대한마취과학회지

BACKGROUND: The worldwide standard of renal replacement therapy for acute renal failure patients is intermittent hemodialysis (IHD). Continuous renal replacement therapy (CRRT) has recently emerged as an alternative modality. We performed the study to find the effects of renal replacement therapy on outcome of the acute renal failure patients in the ICU. METHODS: 373 adult patients under the diagnosis of acute renal failure (ARF) in the ICUs (medical-surgical and coronary care unit) at Severance Hospital Yonsei University College of Medicine between January 1, 1998 and July 31, 2002 were included. Patients with ARF were divided into two groups depending on their need for renal replacement therapy. Renal replacement therapy group was subdivided into IHD and CRRT group. RESULTS: There was significant difference in the mortality between renal replacement group and non-renal replacement group, 74.4% vs. 45.2% (P < 0.001). Renal function recovery rate of renal replacement group was lower compared to that of non-renal replacement group, 36 % vs. 59% (P < 0.001). APACHE II score, ventilator support, vasopressors, number of organ failure, and oliguria during RRT were higher in CRRT group than in IHD group (P < 0.001). CRRT group was associated with higher mortality rate, CRRT 86.2% vs. IHD 42.2% and lower renal function recovery rate, CRRT 9.8% vs. IHD 63.0% (P < 0.001). CONCLUSIONS: Although the result of this study implies that IHD is associated with better survival and better renal recovery, the preferred use of CRRT in severely ill patients with an unstable circulatory system must be reminded.

Effects of Acute Normovolemic Hemodilution under Induced Hypotension on Blood Saving and Homologous Transfusion in Orthognathic Two Jaw Surgery / 대한마취과학회지

BACKGROUND: To avoid complications of homologous transfusion, many methods are being used in patients who undergo an operation, and autologous transfusion is the most popular modality. Acute normovolemic hemodilution (ANH) is recognized as the easiest, the most economical and valuable autologous blood saving method among the types of autotransfusion. This study was performed to investigate the clinical usefulness of ANH under induced hypotensive anesthesia to reduce blood loss and homologous transfusion in orthognathic two jaw operation. METHODS: Thirty patients were randomized divided into two groups; with ANH (n = 15) and without ANH (n = 15). The surgery was limited to one surgeon, with genioplasty, and no bone graft. All patients were pre-donated 2 units of autologous blood before operation. All the surgery was done under induced hypotension by nitroglycerine and esmolol, target mean arterial pressure was aimed at 70% of preoperative blood pressure. In with ANH group, autologous blood were procured immediately after anesthetic induction while 6% hydroxyethyl starch solution were infused to maintain normovolemia until lowering hematocrit to 28%. RESULTS: The two groups did neither differ significantly with demographic data and preoperative evaluation finding. Nor in operation time, surgeon's satisfaction to surgical field, serial central venous pressure, hematocrit's value, prothrombin time, activated partial thromboplastin time. All patients needed transfusion of pre-donated 2 units of autologous blood during operation, but there was significantly reduced demand for homologous packed RBC transfusion in the with ANH group compared with the control group (0.0 0.0 unit vs. 1.7 1.2 unit, P = 0). Blood saving effects was so greater in with ANH group (total blood loss; 1110.0+/-154.9 cc vs. 833.3+/-156.6 cc, P = 0). In addition, the amount of agents for induced hypotension was smaller in with ANH group (nitroglycerine: 11.3+/-2.4 mg vs. 9.9+/-2.4 mg, P = 0.012, esmolol: 52.0+/-28.2 mg vs. 14.6+/-8.3 mg, P = 0). CONCLUSIONS: ANH with pre-donated autologous blood under induced hypotension can reduce intraoperative blood loss and homologous transfusion requirements in orthognathic two jaw operation.