Prospective, Assessment of Vitamin D and Calcium Supplementation, Improvement of Nutritional Status and Preoperative Rehabilitation in Patients Before Knee Arthroplasty.

Visual Analogue Scale (VAS) is a measure determining the intensity of pain by means of a visual analogue scale. Subject is marking the examined point on a line of 10 cm long, where the value 0 is assigned the total absence of pain, and 10 the strongest pain that can be imagined.

Concentration of vitamin D in blood is a laboratory parameter, measured in unit of ng/ml. Levels below 20 ng/ml is a severe vitamin D deficiency condition that requires treatment. The result in the range 20-30 ng/ml means that the vitamin level is not sufficient. Values between 30-50 ng/ml are considered normal. This is one of the basic laboratory parameters for assessing the body's bone mineral metabilism.

The Knee Injury and Osteoarthritis Outcome Score (KOOS) is a questionnaire designed to assess short and long-term patient-relevant outcomes following knee injury. The KOOS is self-administered and assesses five outcomes: pain, symptoms, activities of daily living, sport and recreation function, and knee-related quality of life. Scores are transformed to a 0-100 scale, with zero representing extreme knee problems and 100 representing no knee problems as common in orthopaedic scales and generic measures. Scores between 0 and 100 represent the percentage of total possible score achieved.

Calcium ionized concentration in blood is a laboratory parameter, measured in unit of mmol/l. The results below 1.16 mmol/l mean that the level is not sufficient, condition called hypocalcemia. Values between 1.16-1.32 mmol/l are considered normal. The results above 1.32 mmol/l mean hypercalcemia occurs. This is one of the basic laboratory parameters for assessing the body's bone mineral metabilism.

Total protein concentration in blood is a laboratory parameter, measured in unit of g/l. The results below 60 g/l mean that the level is not sufficient, condition called hypoproteinemia. Values between 60-80 g/l are considered normal. The results above 80 g/l mean hyperproteinemia occurs. This is one of the basic laboratory parameters for assessing the body's nutritional status.

Albumin concentration in blood is a laboratory parameter, measured in unit of mg/ml. The results below 35 mg/l mean that the level is not sufficient, condition called hypoalbuminemia. Values between 35-50 mg/ml are considered normal. The results above 50mg/l mean hyperalbuminemia occurs. This is one of the basic laboratory parameters for assessing the body's nutritional status.

C-reactive protein concentration in blood is a laboratory parameter, measured in unit of mg/l. The results below 5 mg/l are considered normal. The results above 5mg/l mean infection, trauma, stress or other aggravating factor. This is the major laboratory parameter for assessing homeostatic balance.

Subjective global assessment (SGA) is the gold standard for diagnosing malnutrition. SGA is a simple bedside questionnaire method used to diagnose malnutrition and identify those who would benefit from nutrition care. The assessment includes taking a history of recent intake, weight change, gastrointestinal symptoms and a clinical evaluation. Results are on a scale from 1 to 7. Values 1 and 2 means high risk of malnutririon, from 3 do 5 medium risk, and from 6 do 7 mild risk.

Simple Calculated Osteoporosis Risk Estimation (SCORE) scale is the questionnaire tool for diagnosing Osteoporosis risk. It has been reported to appropriately identify person who should be referred for bone densitometry. Results are on a scale from 0 to 50 points. Points from 16 to 50 means high risk of osteoporosis , points from 7 to 15 moderate risk and from 0 do 6 low risk of osteoporosis.

The Duke Activity Status Index is a self-administered questionnaire that measures a patient's functional capacity. It can be used to get a rough estimate of a patient's peak oxygen uptake. Results are on a scale from 0 to 57,95 points. The higher the score, the more intense the acceptable physical activity.

Cardiac Risk Index for Orthopedic Surgery (Lee) is the questionnaire tool for diagnosing cardiovascular hazard in orthopedics patients. Results are on a scale from 0 to 6 points. Points from 3 to 6 means estimated risk of 4%, 2 points is 2,3% of risk, 1 point is 1,7% of risk and 0 points means less than 1 % of cardiovascular event.

Fear Avoidance Beliefs Questionnaire (FABQ) scale is a questionnaire based on the Fear-Avoidance Model of Exaggerated Pain Perception, a model created in attempts to explain why some patients with acute painful conditions can recover while other patients develop chronic pain from such conditions. The FABQ focuses specifically on how a patient's fear-avoidance beliefs about physical activity and work. It consists of 16 questions scaled form 0 do 6, higher score indicates fear avoidance behaviors.

The Quality of Life (QOLS) scale is the most known scale measures factors like satisfaction, perceptions of control, involvement, commitment, and work-life balance, in terms of one's personal perception. QOLS has 16 items, scaled form 1 do 7, higher score indicates superior appraisal of each aspect of life.

Incidence of Adverse Events (AE) was summed up and analyzed in each group. They were divided into 7 groups.

• - a serous wound leak requiring albumin transfusion
• - bleeding that requires RBC transfusion
• - perioperative infection
• - postoperative infection
• - pulmonary embolism
• - other
• - death. Every case was appropriately assigned, analyzed and evaluated.