Osteoarthritis (OA) is the main cause of pain and disability in elderly. For knee OA, a total knee replacement (TKR) is an effective surgical treatment, and the majority of patients report substantial pain relief and functional improvement following surgery. However, 20-40% of patients undergoing TKR are dissatisfied with postsurgical outcome. Even after revision, some patients keep complaining of persisting pain. In this study, the investigators will examine putative prognostic factors on the basis of the biopsychosocial model. Besides several psychological factors (measured with questionnaires), the investigators will assess structural impairments (such as radiographic severity of OA), functional impairments (muscle weakness and proprioceptive deficits), anesthetic procedures, immediate postoperative pain management, metabolic factors (body composition and hemoglobin A1c), inflammatory factors (C-Reactive Protein) and the investigators also will examine the role of altered central pain processing (CPP) (primary and secondary mechanical hyperalgesia, mechanical temporal summation, thermal primary and secondary hyperalgesia, endogenous pain modulation). With a longitudinal study design, this study will explore which factors are predictive of poor outcome in knee OA patients after TKR. Moreover, the interrelationship between CPP, structural, functional, metabolic, inflammatory and psychological factors, and the clinical expression of knee OA (pain, symptoms, physical performance and quality of life) will be investigated. Further research on the role of the aforementioned putative prognostic factors on postsurgical outcome could contribute to better management of these patients, since these factors may be particularly important for patient-tailored treatment.
Study Type
OBSERVATIONAL
Enrollment
223
Total knee arthroplasty surgery will be performed by different orthopedist.
University of Antwerp
Antwerp, Belgium
Pain intensity
The subscale 'Pain' of the Knee injury and Osteoarthritis Outcome Score (KOOS) will be used as primary outcome measure. Minimum score is 0, maximum score is 36. Scores are always transformed to a 0-100 scale. The higher the score, the higher the pain intensity.
Time frame: Change from baseline pain intensity at 3 months postoperative
Pain intensity
The subscale 'Pain' of the Knee injury and Osteoarthritis Outcome Score (KOOS) will be used as primary outcome measure. Minimum score is 0, maximum score is 36. Scores are always transformed to a 0-100 scale. The higher the score, the higher the pain intensity.
Time frame: Change from baseline pain intensity at 1 year postoperative
Pain intensity
The subscale 'Pain' of the Knee injury and Osteoarthritis Outcome Score (KOOS) will be used as primary outcome measure. Minimum score is 0, maximum score is 36. Scores are always transformed to a 0-100 scale. The higher the score, the higher the pain intensity.
Time frame: Change from 3 months postoperative at 1 year postoperative
Pain intensity
The subscale 'Pain' of the Knee injury and Osteoarthritis Outcome Score (KOOS) will be used as primary outcome measure. Minimum score is 0, maximum score is 36. Scores are always transformed to a 0-100 scale. The higher the score, the higher the pain intensity.
Time frame: Baseline (preoperative)
Pain intensity
The subscale 'Pain' of the Knee injury and Osteoarthritis Outcome Score (KOOS) will be used as primary outcome measure. Minimum score is 0, maximum score is 36. Scores are always transformed to a 0-100 scale. The higher the score, the higher the pain intensity.
Time frame: 3 months postoperative
Pain intensity
The subscale 'Pain' of the Knee injury and Osteoarthritis Outcome Score (KOOS) will be used as primary outcome measure. Minimum score is 0, maximum score is 36. Scores are always transformed to a 0-100 scale. The higher the score, the higher the pain intensity.
Time frame: 1 year postoperative
Central pain processing: mechanical local and widespread hyperalgesia allodynia
Measured with quantitative sensory testing (QST): mechanical pain pressure threshold measured with digital algometer at the medial knee joint line, lateral knee joint line and m. Tibialis anterior of affected leg, m. extensor carpi radialis of non-dominant arm and forehead.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Central pain processing: mechanical local and widespread hyperalgesia allodynia
Measured with quantitative sensory testing (QST): mechanical pain pressure threshold measured with digital algometer at the medial knee joint line, lateral knee joint line and m. Tibialis anterior of affected leg, m. extensor carpi radialis of non-dominant arm and forehead.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Central pain processing: mechanical local and widespread hyperalgesia allodynia
Measured with quantitative sensory testing (QST): mechanical pain pressure threshold measured with digital algometer at the medial knee joint line, lateral knee joint line and m. Tibialis anterior of affected leg, m. extensor carpi radialis of non-dominant arm and forehead.
Time frame: Change from 3 months postoperative to 1 year postoperative
Central pain processing: mechanical local and widespread hyperalgesia allodynia
Measured with quantitative sensory testing (QST): mechanical pain pressure threshold measured with digital algometer at the medial knee joint line, lateral knee joint line and m. Tibialis anterior of affected leg, m. extensor carpi radialis of non-dominant arm and forehead.
Time frame: Baseline (preoperative)
Central pain processing: mechanical local and widespread hyperalgesia allodynia
Measured with quantitative sensory testing (QST): mechanical pain pressure threshold measured with digital algometer at the medial knee joint line, lateral knee joint line and m. Tibialis anterior of affected leg, m. extensor carpi radialis of non-dominant arm and forehead.
Time frame: 3 months postoperative
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Central pain processing: mechanical local and widespread hyperalgesia allodynia
Measured with quantitative sensory testing (QST): mechanical pain pressure threshold measured with digital algometer at the medial knee joint line, lateral knee joint line and m. Tibialis anterior of affected leg, m. extensor carpi radialis of non-dominant arm and forehead.
Time frame: 1 year postoperative
Central pain processing: bottom-up sensitization
Measured with quantitative sensory testing (QST): temporal summation measured with a 60g Von Frey monofilament at the medial knee and lateral knee of affected leg, dorsal wrist of affected side
Time frame: Change from baseline (preoperative) to 3 months postoperative
Central pain processing: bottom-up sensitization
Measured with quantitative sensory testing (QST): temporal summation measured with a 60g Von Frey monofilament at the medial knee and lateral knee of affected leg, dorsal wrist of affected side
Time frame: Change from baseline (preoperative) to 1 year postoperative
Central pain processing: bottom-up sensitization
Measured with quantitative sensory testing (QST): temporal summation measured with a 60g Von Frey monofilament at the medial knee and lateral knee of affected leg, dorsal wrist of affected side
Time frame: Change from 3 months postoperative to 1 year postoperative
Central pain processing: bottom-up sensitization
Measured with quantitative sensory testing (QST): temporal summation measured with a 60g Von Frey monofilament at the medial knee and lateral knee of affected leg, dorsal wrist of affected side
Time frame: Baseline (preoperative)
Central pain processing: bottom-up sensitization
Measured with quantitative sensory testing (QST): temporal summation measured with a 60g Von Frey monofilament at the medial knee and lateral knee of affected leg, dorsal wrist of affected side
Time frame: 3 months postoperative
Central pain processing: bottom-up sensitization
Measured with quantitative sensory testing (QST): temporal summation measured with a 60g Von Frey monofilament at the medial knee and lateral knee of affected leg, dorsal wrist of affected side
Time frame: 1 year postoperative
Central pain processing: Thermal hyperalgesia
Measured with quantitative sensory testing (QST): thermal pain sensitivity measured with thermal rollers (Rolltemp II somedic senselab) at the medial knee and lateral knee of affected leg and m. extensor carpi radialis of non-dominant arm.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Central pain processing: Thermal hyperalgesia
Measured with quantitative sensory testing (QST): thermal pain sensitivity measured with thermal rollers (Rolltemp II somedic senselab) at the medial knee and lateral knee of affected leg and m. extensor carpi radialis of non-dominant arm.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Central pain processing: Thermal hyperalgesia
Measured with quantitative sensory testing (QST): thermal pain sensitivity measured with thermal rollers (Rolltemp II somedic senselab) at the medial knee and lateral knee of affected leg and m. extensor carpi radialis of non-dominant arm.
Time frame: Change from 3 months postoperative to 1 year postoperative
Central pain processing: Thermal hyperalgesia
Measured with quantitative sensory testing (QST): thermal pain sensitivity measured with thermal rollers (Rolltemp II somedic senselab) at the medial knee and lateral knee of affected leg and m. extensor carpi radialis of non-dominant arm.
Time frame: Baseline (preoperative)
Central pain processing: Thermal hyperalgesia
Measured with quantitative sensory testing (QST): thermal pain sensitivity measured with thermal rollers (Rolltemp II somedic senselab) at the medial knee and lateral knee of affected leg and m. extensor carpi radialis of non-dominant arm.
Time frame: 3 months postoperative
Central pain processing: Thermal hyperalgesia
Measured with quantitative sensory testing (QST): thermal pain sensitivity measured with thermal rollers (Rolltemp II somedic senselab) at the medial knee and lateral knee of affected leg and m. extensor carpi radialis of non-dominant arm.
Time frame: 1 year postoperative
Central pain processing: dysfunctional endogenous pain analgesia
Measured with quantitative sensory testing (QST): conditioned pain modulation measured Medoc at both wrists
Time frame: Change from baseline (preoperative) to 3 months postoperative
Central pain processing: dysfunctional endogenous pain analgesia
Measured with quantitative sensory testing (QST): conditioned pain modulation measured Medoc at both wrists
Time frame: Change from baseline (preoperative) to 1 year postoperative
Central pain processing: dysfunctional endogenous pain analgesia
Measured with quantitative sensory testing (QST): conditioned pain modulation measured Medoc at both wrists
Time frame: Change from 3 months postoperative to 1 year postoperative
Central pain processing: dysfunctional endogenous pain analgesia
Measured with quantitative sensory testing (QST): conditioned pain modulation measured Medoc at both wrists
Time frame: Baseline (preoperative)
Central pain processing: dysfunctional endogenous pain analgesia
Measured with quantitative sensory testing (QST): conditioned pain modulation measured Medoc at both wrists
Time frame: 3 months postoperative
Central pain processing: dysfunctional endogenous pain analgesia
Measured with quantitative sensory testing (QST): conditioned pain modulation measured Medoc at both wrists
Time frame: 1 year postoperative
Central pain processing: somatic and emotional symptoms
Questionnaire: the Central sensitization Inventory (CSI). Minimum score is 0, maximum score is 100. The higher the score, the higher the chance for the presence of central sensitization.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Central pain processing: somatic and emotional symptoms
Questionnaire: the Central sensitization Inventory (CSI). Minimum score is 0, maximum score is 100. The higher the score, the higher the chance for the presence of central sensitization.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Central pain processing: somatic and emotional symptoms
Questionnaire: the Central sensitization Inventory (CSI). Minimum score is 0, maximum score is 100. The higher the score, the higher the chance for the presence of central sensitization.
Time frame: Change from 3 months postoperative to 1 year postoperative
Central pain processing: somatic and emotional symptoms
Questionnaire: the Central sensitization Inventory (CSI). Minimum score is 0, maximum score is 100. The higher the score, the higher the chance for the presence of central sensitization.
Time frame: Baseline (preoperative)
Central pain processing: somatic and emotional symptoms
Questionnaire: the Central sensitization Inventory (CSI). Minimum score is 0, maximum score is 100. The higher the score, the higher the chance for the presence of central sensitization.
Time frame: 3 months postoperative
Central pain processing: somatic and emotional symptoms
Questionnaire: the Central sensitization Inventory (CSI). Minimum score is 0, maximum score is 100. The higher the score, the higher the chance for the presence of central sensitization.
Time frame: 1 year postoperative
Central pain processing: areas of pain
Body chart: Expanded distribution of Pain (EDP). The more pain locations, the more chance for the presence of central sensitization
Time frame: Change from baseline (preoperative) to 3 months postoperative
Central pain processing: areas of pain
Body chart: Expanded distribution of Pain (EDP). The more pain locations, the more chance for the presence of central sensitization
Time frame: Change from baseline (preoperative) to 1 year postoperative
Central pain processing: areas of pain
Body chart: Expanded distribution of Pain (EDP). The more pain locations, the more chance for the presence of central sensitization
Time frame: Change from 3 months postoperative to 1 year postoperative
Central pain processing: areas of pain
Body chart: Expanded distribution of Pain (EDP). The more pain locations, the more chance for the presence of central sensitization
Time frame: Baseline (preoperative)
Central pain processing: areas of pain
Body chart: Expanded distribution of Pain (EDP). The more pain locations, the more chance for the presence of central sensitization
Time frame: 3 months postoperative
Central pain processing: areas of pain
Body chart: Expanded distribution of Pain (EDP). The more pain locations, the more chance for the presence of central sensitization
Time frame: 1 year postoperative
Psychosocial factors: pain catastrophizing
Measured with Pain Catastrophizing Scale (PCS). Minimum score is 0, maximum score is 52. The higher the score, the higher the pain catastrophizing.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Psychosocial factors: pain catastrophizing
Measured with Pain Catastrophizing Scale (PCS). Minimum score is 0, maximum score is 52. The higher the score, the higher the pain catastrophizing.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Psychosocial factors: pain catastrophizing
Measured with Pain Catastrophizing Scale (PCS). Minimum score is 0, maximum score is 52. The higher the score, the higher the pain catastrophizing.
Time frame: Change from 3 months postoperative to 1 year postoperative
Psychosocial factors: pain catastrophizing
Measured with Pain Catastrophizing Scale (PCS). Minimum score is 0, maximum score is 52. The higher the score, the higher the pain catastrophizing.
Time frame: Baseline (preoperative)
Psychosocial factors: pain catastrophizing
Measured with Pain Catastrophizing Scale (PCS). Minimum score is 0, maximum score is 52. The higher the score, the higher the pain catastrophizing.
Time frame: 3 months postoperative
Psychosocial factors: pain catastrophizing
Measured with Pain Catastrophizing Scale (PCS). Minimum score is 0, maximum score is 52. The higher the score, the higher the pain catastrophizing.
Time frame: 1 year postoperative
Psychosocial factors: illness perceptions
Illness perception questionnaire-revised (IPQ-R) 1. Identity dimension: yes = 1; no = 0 min score= 0, max score= 18 2. Other dimensions: min score= 38, max score= 190 strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 3. Causal dimension: strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 min score= 18, max score= 90 High scores on the identity, timeline, consequences, and cyclical dimensions represent strongly held beliefs about the number of symptoms attributed to the illness, the chronicity of the condition, the negative consequences of the illness, and the cyclical nature of the condition. High scores on the personal control, treatment control and coherence dimensions, represent positive beliefs about the controllability of the illness and a personal understanding of the condition.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Psychosocial factors: illness perceptions
Illness perception questionnaire-revised (IPQ-R) 1. Identity dimension: yes = 1; no = 0 min score= 0, max score= 18 2. Other dimensions: min score= 38, max score= 190 strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 3. Causal dimension: strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 min score= 18, max score= 90 High scores on the identity, timeline, consequences, and cyclical dimensions represent strongly held beliefs about the number of symptoms attributed to the illness, the chronicity of the condition, the negative consequences of the illness, and the cyclical nature of the condition. High scores on the personal control, treatment control and coherence dimensions, represent positive beliefs about the controllability of the illness and a personal understanding of the condition.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Psychosocial factors: illness perceptions
Illness perception questionnaire-revised (IPQ-R) 1. Identity dimension: yes = 1; no = 0 min score= 0, max score= 18 2. Other dimensions: min score= 38, max score= 190 strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 3. Causal dimension: strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 min score= 18, max score= 90 High scores on the identity, timeline, consequences, and cyclical dimensions represent strongly held beliefs about the number of symptoms attributed to the illness, the chronicity of the condition, the negative consequences of the illness, and the cyclical nature of the condition. High scores on the personal control, treatment control and coherence dimensions, represent positive beliefs about the controllability of the illness and a personal understanding of the condition.
Time frame: Change from 3 months postoperative to 1 year postoperative
Psychosocial factors: illness perceptions
Illness perception questionnaire-revised (IPQ-R) 1. Identity dimension: yes = 1; no = 0 min score= 0, max score= 18 2. Other dimensions: min score= 38, max score= 190 strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 3. Causal dimension: strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 min score= 18, max score= 90 High scores on the identity, timeline, consequences, and cyclical dimensions represent strongly held beliefs about the number of symptoms attributed to the illness, the chronicity of the condition, the negative consequences of the illness, and the cyclical nature of the condition. High scores on the personal control, treatment control and coherence dimensions, represent positive beliefs about the controllability of the illness and a personal understanding of the condition.
Time frame: Baseline (preoperative)
Psychosocial factors: illness perceptions
Illness perception questionnaire-revised (IPQ-R) 1. Identity dimension: yes = 1; no = 0 min score= 0, max score= 18 2. Other dimensions: min score= 38, max score= 190 strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 3. Causal dimension: strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 min score= 18, max score= 90 High scores on the identity, timeline, consequences, and cyclical dimensions represent strongly held beliefs about the number of symptoms attributed to the illness, the chronicity of the condition, the negative consequences of the illness, and the cyclical nature of the condition. High scores on the personal control, treatment control and coherence dimensions, represent positive beliefs about the controllability of the illness and a personal understanding of the condition.
Time frame: 3 months postoperative
Psychosocial factors: illness perceptions
Illness perception questionnaire-revised (IPQ-R) 1. Identity dimension: yes = 1; no = 0 min score= 0, max score= 18 2. Other dimensions: min score= 38, max score= 190 strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 3. Causal dimension: strongly disagree =1, disagree =2, neither agree or disagree = 3, agree = 4, strongly agree = 5 min score= 18, max score= 90 High scores on the identity, timeline, consequences, and cyclical dimensions represent strongly held beliefs about the number of symptoms attributed to the illness, the chronicity of the condition, the negative consequences of the illness, and the cyclical nature of the condition. High scores on the personal control, treatment control and coherence dimensions, represent positive beliefs about the controllability of the illness and a personal understanding of the condition.
Time frame: 1 year postoperative
Psychosocial factors: anxiety
Measured with Hospital Anxiety and Depression Scale (HADS), subscale anxiety. Minimum score is 0, maximum score is 21. The higher the score, the higher the anxiety.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Psychosocial factors: anxiety
Measured with Hospital Anxiety and Depression Scale (HADS), subscale anxiety. Minimum score is 0, maximum score is 21. The higher the score, the higher the anxiety.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Psychosocial factors: anxiety
Measured with Hospital Anxiety and Depression Scale (HADS), subscale anxiety. Minimum score is 0, maximum score is 21. The higher the score, the higher the anxiety.
Time frame: Change from 3 months postoperative to 1 year postoperative
Psychosocial factors: anxiety
Measured with Hospital Anxiety and Depression Scale (HADS), subscale anxiety. Minimum score is 0, maximum score is 21. The higher the score, the higher the anxiety.
Time frame: Baseline (preoperative)
Psychosocial factors: anxiety
Measured with Hospital Anxiety and Depression Scale (HADS), subscale anxiety. Minimum score is 0, maximum score is 21. The higher the score, the higher the anxiety.
Time frame: 3 months postoperative
Psychosocial factors: anxiety
Measured with Hospital Anxiety and Depression Scale (HADS), subscale anxiety. Minimum score is 0, maximum score is 21. The higher the score, the higher the anxiety.
Time frame: 1 year postoperative
Psychosocial factors: depression
Measured with Hospital Anxiety and Depression Scale (HADS), subscale depression. Minimum score is 0, maximum score is 21. The higher the score, the higher the depression.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Psychosocial factors: depression
Measured with Hospital Anxiety and Depression Scale (HADS), subscale depression. Minimum score is 0, maximum score is 21. The higher the score, the higher the depression.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Psychosocial factors: depression
Measured with Hospital Anxiety and Depression Scale (HADS), subscale depression. Minimum score is 0, maximum score is 21. The higher the score, the higher the depression.
Time frame: Change from 3 months postoperative to 1 year postoperative
Psychosocial factors: depression
Measured with Hospital Anxiety and Depression Scale (HADS), subscale depression. Minimum score is 0, maximum score is 21. The higher the score, the higher the depression.
Time frame: Baseline (preoperative)
Psychosocial factors: depression
Measured with Hospital Anxiety and Depression Scale (HADS), subscale depression. Minimum score is 0, maximum score is 21. The higher the score, the higher the depression.
Time frame: 3 months postoperative
Psychosocial factors: depression
Measured with Hospital Anxiety and Depression Scale (HADS), subscale depression. Minimum score is 0, maximum score is 21. The higher the score, the higher the depression.
Time frame: 1 year postoperative
Functional factors: Maximal voluntary muscle strength m. Hamstrings
Strength m. Hamstrings of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Change from baseline (preoperative) to 3 months postoperative
Functional factors: Maximal voluntary muscle strength m. Hamstrings
Strength m. Hamstrings of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Change from baseline (preoperative) to 1 year postoperative
Functional factors: Maximal voluntary muscle strength m. Hamstrings
Strength m. Hamstrings of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Change from 3 months postoperative to 1 year postoperative
Functional factors: Maximal voluntary muscle strength m. Hamstrings
Strength m. Hamstrings of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: 3 months postoperative
Functional factors: Maximal voluntary muscle strength m. Hamstrings
Strength m. Hamstrings of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Baseline (preoperative)
Functional factors: Maximal voluntary muscle strength m. Hamstrings
Strength m. Hamstrings of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: 1 year postoperative
Functional factors: Maximal voluntary muscle strength m. Quadriceps
Strength m. Quadriceps of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Change from baseline (preoperative) to 3 months postoperative
Functional factors: Maximal voluntary muscle strength m. Quadriceps
Strength m. Quadriceps of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Change from baseline (preoperative) to 1 year postoperative
Functional factors: Maximal voluntary muscle strength m. Quadriceps
Strength m. Quadriceps of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Change from 3 months postoperative to 1 year postoperative
Functional factors: Maximal voluntary muscle strength m. Quadriceps
Strength m. Quadriceps of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: Baseline (preoperative)
Functional factors: Maximal voluntary muscle strength m. Quadriceps
Strength m. Quadriceps of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: 3 months postoperative
Functional factors: Maximal voluntary muscle strength m. Quadriceps
Strength m. Quadriceps of both legs, measured with Biodex System 4 pro - dynamometer
Time frame: 1 year postoperative
Functional factors: proprioceptive accuracy
Proprioception of the knee of both legs, measured with inclinometer
Time frame: Change from baseline (preoperative) to 3 months postoperative
Functional factors: proprioceptive accuracy
Proprioception of the knee of both legs, measured with inclinometer
Time frame: Change from baseline (preoperative) to 1 year postoperative
Functional factors: proprioceptive accuracy
Proprioception of the knee of both legs, measured with inclinometer
Time frame: Change from 3 months postoperative to 1 year postoperative
Functional factors: proprioceptive accuracy
Proprioception of the knee of both legs, measured with inclinometer
Time frame: Baseline (preoperative)
Functional factors: proprioceptive accuracy
Proprioception of the knee of both legs, measured with inclinometer
Time frame: 3 months postoperative
Functional factors: proprioceptive accuracy
Proprioception of the knee of both legs, measured with inclinometer
Time frame: 1 year postoperative
Functional factors: leg strength and endurance
Measured with 30 seconds Timed Chair-Stand-Test
Time frame: Change from baseline (preoperative) to 3 months postoperative
Functional factors: leg strength and endurance
Measured with 30 seconds Timed Chair-Stand-Test
Time frame: Change from baseline (preoperative) to 1 year postoperative
Functional factors: leg strength and endurance
Measured with 30 seconds Timed Chair-Stand-Test
Time frame: Change from 3 months postoperative to 1 year postoperative
Functional factors: leg strength and endurance
Measured with 30 seconds Timed Chair-Stand-Test
Time frame: Baseline (preoperative)
Functional factors: leg strength and endurance
Measured with 30 seconds Timed Chair-Stand-Test
Time frame: 3 months postoperative
Functional factors: leg strength and endurance
Measured with 30 seconds Timed Chair-Stand-Test
Time frame: 1 year postoperative
Patient demographics
measured with Knee Society Scoring System (KSS): subscale patient demographics (nominal)
Time frame: Baseline (preoperative)
Alignment
measured with Knee Society Scoring System (KSS): subscale objective knee score 'alignment': weight-bearing anterior-posterior radiograph measuring the femoral-tibial (Anatomic) axis. Minimum is 0, maximum is 25. The higher the score, the better the alignment.
Time frame: Baseline (preoperative)
Instability
measured with Knee Society Scoring System (KSS): subscale objective knee score 'instability'. Minimum is 0, maximum is 25. The higher the score, the better the stability.
Time frame: Baseline (preoperative)
Joint motion
measured with Knee Society Scoring System (KSS): subscale objective knee score 'joint motion'. Minimum is 0, maximum can be higher than 25. One point for every joint motion of 5 degrees. The higher the score, the better the joint motion.
Time frame: Baseline (preoperative)
Pain symptoms
measured with Knee Society Scoring System (KSS): subscale symptoms. Minimum score is 0, maximum score is 25. The higher the score, the worse the pain symptoms.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Pain symptoms
measured with Knee Society Scoring System (KSS): subscale symptoms. Minimum score is 0, maximum score is 25. The higher the score, the worse the pain symptoms.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Pain symptoms
measured with Knee Society Scoring System (KSS): subscale symptoms. Minimum score is 0, maximum score is 25. The higher the score, the worse the pain symptoms.
Time frame: Change from 3 months postoperative to 1 year postoperative
Pain symptoms
measured with Knee Society Scoring System (KSS): subscale symptoms. Minimum score is 0, maximum score is 25. The higher the score, the worse the pain symptoms.
Time frame: Baseline (preoperative)
Pain symptoms
measured with Knee Society Scoring System (KSS): subscale symptoms. Minimum score is 0, maximum score is 25. The higher the score, the worse the pain symptoms.
Time frame: 3 months postoperative
Pain symptoms
measured with Knee Society Scoring System (KSS): subscale symptoms. Minimum score is 0, maximum score is 25. The higher the score, the worse the pain symptoms.
Time frame: 1 year postoperative
Patient expectations
measured with Knee Society Scoring System (KSS): subscale patient expectations. Minimum score is 0, maximum score is 15. The higher the score, the higher the patient's opinion on the extent to which the patient expects that the operation will improve their knee pain, and their ability to perform their activities of daily living and recreational activities
Time frame: Baseline (preoperative)
Patient expectations fulfillment
measured with Knee Society Scoring System (KSS): subscale patient expectations. Minimum score is 0, maximum score is 15. The higher the score, the higher the patient's opinion on the extent to which the outcome after the operation has met the patient's pre-operative expectations with respect to pain and function
Time frame: 3 months postoperative
Patient expectations fulfillment
measured with Knee Society Scoring System (KSS): subscale patient expectations. Minimum score is 0, maximum score is 15. The higher the score, the higher the patient's opinion on the extent to which the outcome after the operation has met the patient's pre-operative expectations with respect to pain and function
Time frame: 1 year postoperative
Patient expectations fulfillment
measured with Knee Society Scoring System (KSS): subscale patient expectations. Minimum score is 0, maximum score is 15. The higher the score, the higher the patient's opinion on the extent to which the outcome after the operation has met the patient's pre-operative expectations with respect to pain and function
Time frame: Change from 3 months postoperative to 1 year postoperative
Patient satisfaction
measured with Knee Society Scoring System (KSS): subscale patient satisfaction. Minimum score is 0, maximum score is 40. The higher the score, the more satisfied the patient feels with their knee.
Time frame: Change from baseline (preoperative) to 3 months postoperative
Patient satisfaction
measured with Knee Society Scoring System (KSS): subscale patient satisfaction. Minimum score is 0, maximum score is 40. The higher the score, the more satisfied the patient feels with their knee.
Time frame: Change from baseline (preoperative) to 1 year postoperative
Patient satisfaction
measured with Knee Society Scoring System (KSS): subscale patient satisfaction. Minimum score is 0, maximum score is 40. The higher the score, the more satisfied the patient feels with their knee.
Time frame: Change from 3 months postoperative to 1 year postoperative
Patient satisfaction
measured with Knee Society Scoring System (KSS): subscale patient satisfaction. Minimum score is 0, maximum score is 40. The higher the score, the more satisfied the patient feels with their knee.
Time frame: Baseline (preoperative)
Patient satisfaction
measured with Knee Society Scoring System (KSS): subscale patient satisfaction. Minimum score is 0, maximum score is 40. The higher the score, the more satisfied the patient feels with their knee.
Time frame: 3 months postoperative
Patient satisfaction
measured with Knee Society Scoring System (KSS): subscale patient satisfaction. Minimum score is 0, maximum score is 40. The higher the score, the more satisfied the patient feels with their knee.
Time frame: 1 year postoperative
Functional score
measured with Knee Society Scoring System (KSS): subscale functional score. Minimum score is 0, maximum score is 100. The higher the score, the better the functionality of the patient
Time frame: Change from baseline (preoperative) to 3 months postoperative
Functional score
measured with Knee Society Scoring System (KSS): subscale functional score. Minimum score is 0, maximum score is 100. The higher the score, the better the functionality of the patient
Time frame: Change from baseline (preoperative) to 1 year postoperative
Functional score
measured with Knee Society Scoring System (KSS): subscale functional score. Minimum score is 0, maximum score is 100. The higher the score, the better the functionality of the patient
Time frame: Change from 3 months postoperative to 1 year postoperative
Functional score
measured with Knee Society Scoring System (KSS): subscale functional score. Minimum score is 0, maximum score is 100. The higher the score, the better the functionality of the patient
Time frame: Baseline (preoperative)
Functional score
measured with Knee Society Scoring System (KSS): subscale functional score. Minimum score is 0, maximum score is 100. The higher the score, the better the functionality of the patient
Time frame: 3 months postoperative
Functional score
measured with Knee Society Scoring System (KSS): subscale functional score. Minimum score is 0, maximum score is 100. The higher the score, the better the functionality of the patient
Time frame: 1 year postoperative
Metabolic factors: Fat mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Change from baseline (preoperative) to 3 months postoperative
Metabolic factors: Fat mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Change from baseline (preoperative) to 1 year postoperative
Metabolic factors: Fat mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Change from 3 months postoperative to 1 year postoperative
Metabolic factors: Fat mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Baseline (preoperative)
Metabolic factors: Fat mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: 3 months postoperative
Metabolic factors: Fat mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: 1 year postoperative
Metabolic factors: Lean mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Change from baseline (preoperative) to 3 months postoperative
Metabolic factors: Lean mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Change from baseline (preoperative) to 1 year postoperative
Metabolic factors: Lean mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Change from 3 months postoperative to 1 year postoperative
Metabolic factors: Lean mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: Baseline (preoperative)
Metabolic factors: Lean mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: 3 months postoperative
Metabolic factors: Lean mass
Measured with Bio-electrical Impedance Analyses (BIA)
Time frame: 1 year postoperative
Metabolic factors: Body mass index (BMI)
Measured with length of patient (cm) and weight of patient (kg)
Time frame: Change from baseline (preoperative) to 3 months postoperative
Metabolic factors: Body mass index (BMI)
Measured with length of patient (cm) and weight of patient (kg)
Time frame: Change from baseline (preoperative) to 1 year postoperative
Metabolic factors: Body mass index (BMI)
Measured with length of patient (cm) and weight of patient (kg)
Time frame: Change from 3 months postoperative to 1 year postoperative
Metabolic factors: Body mass index (BMI)
Measured with length of patient (cm) and weight of patient (kg)
Time frame: Baseline (preoperative)
Metabolic factors: Body mass index (BMI)
Measured with length of patient (cm) and weight of patient (kg)
Time frame: 3 months postoperative
Metabolic factors: Body mass index (BMI)
Measured with length of patient (cm) and weight of patient (kg)
Time frame: 1 year postoperative
Metabolic factors: body composition
Measured with Bioelectrical Impedance Analysis (BIA)
Time frame: Baseline (preoperative), 3 months postoperative, 1 year postoperative.
Metabolic factors: venous blood sample
Measured with A1C test or glycohemoglobin test
Time frame: Change from baseline (preoperative) to 3 months postoperative
Metabolic factors: venous blood sample
Measured with A1C test or glycohemoglobin test
Time frame: Change from baseline (preoperative) to 1 year postoperative
Metabolic factors: venous blood sample
Measured with A1C test or glycohemoglobin test
Time frame: Change from 3 months postoperative to 1 year postoperative
Metabolic factors: venous blood sample
Measured with A1C test or glycohemoglobin test
Time frame: Baseline (preoperative)
Metabolic factors: venous blood sample
Measured with A1C test or glycohemoglobin test
Time frame: 3 months postoperative
Metabolic factors: venous blood sample
Measured with A1C test or glycohemoglobin test
Time frame: 1 year postoperative.
Structural factors
Measured with Kellgren and Lawrence scale on radiography
Time frame: Baseline (preoperative)
Inflammatory factors: signs of inflammation
Measured with the C-reactive protein levels in blood sample (collected from patient record)
Time frame: Baseline (preoperative)
Anesthetic procedure
General anesthesia, spinal anesthesia or combination with peripheral block
Time frame: During surgery
Clinical pain score
Measured with numeric rating pain scale
Time frame: day 1 and 2 postoperative