Introduction: The only treatment for grade IV knee osteoarthritis is total knee arthroplasty (TKA) irrespective of the age of the patient.Most of the grade IV OA patient are elderly and most likely to have some comorbidities. Age and comorbidities are the major reasons for patient’s reluctance toundergo TKA. A clinical pathway with standard length of stay(LOS) could justify the patient’s hesitation for TKA. The aimof this study was to determine the factors, including age andcomorbidity, that affect the LOS of patients treated with TKA. MaterialsandMethods:This is a retrospective study ofTKA patients in Surabaya Orthopedics and TraumatologyHospital from January 2011 to July 2017. Preoperativecomorbidities were scored using Charlson ComorbidityIndex (CCI) and physical status by ASA (American Societyof Anesthesiologist), classification for age, sex, BMI, bloodloss, operation time, method of anaesthesia andpostoperative day of rehabilitation were recorded as factorspotentially affecting LOS. The discharge criteria for thepatients were ability to ambulate to the bathroom and cleanoperative wound with no complications. The data obtainedwere analysed statistically.Results:The average LOS was 5.58 days, ranging fromthree to eight days. There were no demographic factors thataffected the patients’ LOS. BMI, ASA, CCI, and blood lossdid not significantly affect LOS. Operation time wasbetween 90-140 minutes, and spinal anaesthesia showedsignificant longer LOS, but within the average.Conclusion:Age and comorbidity did not affect length of stay in TKA patients.

Introduction: Percutaneous vertebroplasty (PV) is one of the available treatments for vertebral compression fracture (VCF). Polymethylmethacrylate (PMMA) is the most common bone substitute used in the procedure, but it has several disadvantages. Bioceramic material, such as hydroxyapatite (HA), has better biological activity compared to PMMA. The aim of this study was to find an optimal biomaterial compound which offers the best mechanical and biological properties to be used in PV .M aterials and Methods: This was an experimental studyw ith goat (Capra aegagrus hircus)as an animal model. Thea nimals’ vertebral columns were injected with PMMA-HAc ompound. Animal samples were divided into four groups,a nd each group received a different proportion ofP MMA:HA compound. The mechanical and biologicale ffects of the compound on the bone were then analysed. Them echanical effect was assessed by measuring the vertebralb ody’s compressive strength. Meanwhile, the biologicale ffect was assessed by analysing the callus formation in thev ertebral body. R esults:The optimal callus formation and compressives trength was observed in the group receiving PMMA:HAw ith a 1:2 ratio.C onclusion: A mixture of PMMA and HA increases theq uality of callus formation and the material’s compressives trength. The optimum ratio of PMMA:HA in the compoundi s 1:2.