Psychosocial Factors, Lifestyle and Central Pain Processing as Potential Predictors of Outcome for Rotator Cuff Repair

Rotator Cuff Tear or Rupture, Not Specified as Traumatic Clinical Trial

Official title:

Psychosocial Factors, Lifestyle and Central Pain Processing as Potential Predictors of Outcome After Rehabilitation for Rotator Cuff Repair: A Study Design for a Prospective Longitudinal Cohort Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04946149
• Other study ID #: ID2018-02089
• Status: Completed
• Start date: January 1, 2019
• Est. completion date: May 10, 2022

Study information

• Verified date: August 2022
• Source: Kantonsspital Winterthur KSW
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The influence of modifiable psychosocial and lifestyle factors and the role of central pain processing (CPP) on outcome after rotator cuff repair (RCR) is not well enough established to formulate holistic prognosis. Modern pain neuroscience emphasises to explain musculoskeletal shoulder pain biopsychosocially, which seems short when looking at the yearly RCR increase. This study will explore modifiable psychosocial and lifestyle factors and CPP as potential predictors for outcome after RCR.

Description:

Shoulder pain is the third most common musculoskeletal disorder seen in primary care with low recovery rates (50-60%) 12 to 18 months post onset. Rotator cuff (RC) disorders are the most common amongst shoulder pain patients with a life-time prevalence of around 70%. There is a lack of consensus concerning the cause of shoulder pain, as many people present with structural changes of their RC, yet they do not suffer pain. Reports from the United States acknowledge that only one third of RC lesions are symptomatic. RC degeneration measured in cadavers, increases rapidly from the age of 50 to 55, peaking at 80 years. Contrary to this observed increasing mechanistic change, the pain curve from the age of 65 onwards. This decrease in pain implies that shoulder pain is not solely based upon the presence of a RC tear, or other underlying structural changes.

Patients who demonstrate structural changes of their RC, are still predominantly treated using biomedical reasoning. There was a reported 270,000 annual surgeries in the USA and an increase of 204% in rotator cuff repairs (RCR) between 1998 and 2011 in Finland. Satisfactory outcomes ranged from 38% to 95%. Biomedical prognostic indicators dominate the orthopaedic research on outcomes post RCR. Biomedical factors include; arm function (e.g. muscle strength), radiological findings (e.g. tear size) or demographics (e.g. age). This assertion was backed by a systematic review and meta-analysis regarding prognosis post RCR, where mainly anatomical and functional shoulder factors were analysed.

Despite the reliance on biomedical indicators, there is a growing body of evidence about the impact of psychosocial factors on persistent shoulder pain, and on outcomes after RCR. The biopsychosocial model first described by Engel in the 1970's incorporates multiple dimensions and explains illness or disease based upon biomedical, psychological and social determinants of health. The perception of high job demand, poor social support, baseline high distress, maladaptive pain beliefs such as catastrophic thinking and pain self-efficacy can lead to persistent shoulder pain and disability. The absence of psychological distress is also associated with improved self-efficacy ("the capacity to produce important effects"), and lower levels of pain and disability. However, studies on the influence of psychosocial factors post RCR, demonstrate weak interactions. Patients with existing preoperative psychological conditions like depression and anxiety or cognitive psychological factors like pain catastrophizing and kinesiophobia, and psychological distress demonstrate higher pre-operative pain levels.

High patients' expectations of a positive outcome post RCR show independent and strong associations to satisfactory outcomes after RCR, measured in pain and disability, and performance at one-year post-op. However, it is unclear which circumstances lead to high or low expectations and how one should measure these. Low expectations in conservative treatments like physiotherapy, can be influenced by the patients' biomedical oriented attitudes and beliefs towards pain and disability. High expectations on outcome post RCR may be further driven by the failure of conservative treatments (e.g. Physiotherapy).

Sleep disturbance is highly prevalent in rotator cuff related shoulder pain patients and shoulder pain was found to be a strong predictor for sleep disturbance. RCR seems to reduce this vicious interplay between pain and sleep as findings demonstrate an overall post RCR improvement of sleep quality. The same study did not find any predictive power for insomnia on outcome post RCR.

The relationship between CPP measures such as central sensitisation (CS), or quantitative sensory testing (QST) and prolonged shoulder pain have been established.

To conclude, in the literature there is a lack of knowledge about modifiable psychosocial and lifestyle factors and CPP for predicting outcome after RCR. Clinicians need an improved explanatory model to predict successful outcomes post RCR. Neither the local tissue pathology-pain model nor the growing knowledge about local biochemical changes in the tendons, sufficiently describe the relationship between tissue changes and perceived shoulder pain. There is insufficient understanding to what extent cognitive psychological factors like pain catastrophizing, high perceived stress or low self-efficacy may influence outcome after RCR and whether or not they drive high or low patients' expectations (psychosocial factor) for surgery. The role of sleep on outcome after RCR remains obscure. Finally, the association of CPP with prolonged recovery post RCR is unknown.

This study aims to support the understanding of psychosocial factors and their influence on outcome after RCR. The investigators hypothesise that psychosocial factors, lifestyle factors and CPP do play a role in individual prognosis for outcome after RCR. If modifiable psychosocial or lifestyle related factors such as patients' expectations on surgery, catastrophic pain thinking, high perceived stress, altered injury perceptions, sleep disturbance or altered central pain processing are identified as predictors for post RCR outcome, clinicians might tailor treatment and potentially patient selection for RCR based upon improved factors and hypothetically reduce the number of persistent shoulder pain patients one year after onset.

This study aims to answer the following questions:

1. Is there an association between psychosocial factors including expectations, lifestyle factors such as sleep and CPP with outcome (quality of life, pain and disability) after RCR at 12 weeks and 12 months?

2. To what extent do these pre-interventional variables predict post-operative RCR outcome at 12 weeks and 12 months? Methods Study Design and setting The study will be implemented and reported in line with the STROBE statement for observational studies.

Data are obtained monocentric in the shoulder and elbow surgery unit in the clinic of orthopaedic surgery and traumatology in alliance with the institute of therapy and rehabilitation of the acute care hospital, "Kantonsspital Winterthur" in Switzerland.

The current research project will analyze data from three selected time points of this clinical routine of the RCR management; 2-3 weeks preoperative (T1), 12 weeks postoperative (T2) and 12 months postoperative (T3). Data from January 2019 will be considered. Data collection will be stopped after the inclusion of 141 individual datasets with 12 months follow up, estimated to be completed in late Spring 2022.

Demographic variables such as age, gender, and profession and comorbidities, including diabetes, rheumatological disease, cardiovascular disease, and neurological disease, will be registered.

The investigators will use a mixed-effects regression model for repeated measures. This will have the power to detect a moderate effect size that is still clinically relevant (15% difference in WORC score) with confidence level α=0.5, (two-tailed) and a desired power of 90%. The required total sample size was calculated to be 125 subjects (Edland). Mixed models do not require complete datasets to produce accurate results, but the statistical analysts have accounted for potential attrition. Given an expected drop-out rate of approximately 12.5%, a total number of 141 patients is needed. The power is set at 90% to minimize the chance of making a type II error.

Statistical Methods and Analysis Statistical analyses will be performed using RStudio. Level of significance is set at p = 0.05. Appropriate descriptive statistics will be performed. Measurements will take place at three time points in the perioperative management, as described above (T1 = at baseline 2-3 weeks prior to RCR, T2 = at 12 weeks post RCR and T3 = at 12 months post RCR as follow-up).

The primary outcome (WORC) will be analysed using multilevel linear regression models for repeated (longitudinal) measures, using an unstructured covariance matrix. Dependent variables are the primary and secondary outcomes. Continuous secondary outcomes will be assessed in a similar way to the primary outcome. The models will be developed by stepwise reduction of the potential predictors (for, psychosocial factors, sleep and CPP). Categorical data (e.g. EQ-5D-5L) will be analysed using logistic models. For non-repeated continuous and binary measurements, ordinary linear regression and logistic models will be used, respectively. Six predictors as clustered variables will be studied. The psychosocial variables are: 1) expectation, 2) pain catastrophizing, 3) perceived stress, 4) illness perceptions; the lifestyle factor; 5) sleep and 6) central pain processing (see table 2 for more detail).

Data security and management Data generation, transmission, storage and analysis within this project strictly follow Swiss legal requirements for data protection. The electronic data capture (EDC) software REDCap (www.project---redcap.org) will be used for data processing and management. Appropriate coded identification (e.g. pseudonymisation) is used in order to enter subject data into the database. The coding list of target data is saved in a secured folder on the hospital's server.

Ethics The study underlies the principles of the Helsinki Declaration. Only data of patients who gave general consent to the hospital or informed written consent to the project will be considered for analysis. Ethical approval received January 2019 (ID 2018-02089) by the Ethical Committee of the Canton of Zurich, Switzerland.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 142
• Est. completion date: May 10, 2022
• Est. primary completion date: May 10, 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Scheduled for elective arthroscopic RCR;

• First time RCR on the target shoulder;

• Completed primary and secondary outcome measures (Western Ontario Rotator Cuff Index (WORC), Constant Score, Maximum Pain on Numeric Rating Scale and EQ-5D-5L) from daily routine.

Exclusion Criteria:

• Changes of intra operative procedure (e.g. anything but RCR)

• Re-repair of tendon;

• No surgery;

• Other pain-related or neurological comorbidities that could interfere with pain measures;

Related Conditions & MeSH terms

• Rotator Cuff Injuries
• Rotator Cuff Tear or Rupture, Not Specified as Traumatic
• Rupture

Locations

Country	Name	City	State
Switzerland	Kantonsspital Winterthur	Winterthur	Zürich

Sponsors (2)

Lead Sponsor	Collaborator
Kantonsspital Winterthur KSW	Universiteit Antwerpen

Country where clinical trial is conducted

Switzerland, 

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* Note: There are 40 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Potential predictor: Central pain processing: Central sensitization inventory	The original English questionnaire was developed in 2011 to assess key symptoms in relation to central sensitivity symptoms (CSS). It consists of two parts; Part A with 25 items relating to pain, psychosocial aspects, cognitive and functional aspects. Part B with 7 different CSSs, like restless legs, irritable bowel, and multiple chemical sensitivities and 3 disorders like neck pain (whiplash), depression and anxiety or panic attacks.; It is a high-quality measurement tool, with high construct validity and test-retest reliability. The defined cut-off point is at 40 points.	pre operative (T1)
Other	Potential predictor: Central pain processing: Central sensitization inventory	The original English questionnaire was developed in 2011 to assess key symptoms in relation to central sensitivity symptoms (CSS). It consists of two parts; Part A with 25 items relating to pain, psychosocial aspects, cognitive and functional aspects. Part B with 7 different CSSs, like restless legs, irritable bowel, and multiple chemical sensitivities and 3 disorders like neck pain (whiplash), depression and anxiety or panic attacks.; It is a high-quality measurement tool, with high construct validity and test-retest reliability. The defined cut-off point is at 40 points.	12 Weeks postoperative (T2)
Other	Potential predictor: Central pain processing: Central sensitization inventory	The original English questionnaire was developed in 2011 to assess key symptoms in relation to central sensitivity symptoms (CSS). It consists of two parts; Part A with 25 items relating to pain, psychosocial aspects, cognitive and functional aspects. Part B with 7 different CSSs, like restless legs, irritable bowel, and multiple chemical sensitivities and 3 disorders like neck pain (whiplash), depression and anxiety or panic attacks.; It is a high-quality measurement tool, with high construct validity and test-retest reliability. The defined cut-off point is at 40 points.	12 months postoperative (T3)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: cold hyperalgesia	Cold hyperalgesia is measured with a cold pack. The cold application is kept for 10 seconds, and the patients will rate the experienced pain on a NRS from 0 (no pain at all) to 10 (worst imaginable pain).	pre operative (T1)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: cold hyperalgesia	Cold hyperalgesia is measured with a cold pack. The cold application is kept for 10 seconds, and the patients will rate the experienced pain on a NRS from 0 (no pain at all) to 10 (worst imaginable pain).	12 Weeks postoperative (T2)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: cold hyperalgesia	Cold hyperalgesia is measured with a cold pack. The cold application is kept for 10 seconds, and the patients will rate the experienced pain on a NRS from 0 (no pain at all) to 10 (worst imaginable pain).	12 months postoperative (T3)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: Pressure Pain Threshold	Pressure Pain Threshold (PPT): The measurements will be conducted by digital hand-held pressure algometer with a rubber tip of approximately 1 cm² (FPX 50, FORCE TEN by Wagner Instruments), increasing pressure will be given perpendicular to the skin . Measurements are taken at five standardized sites. .	pre operative (T1)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: Pressure Pain Threshold	Pressure Pain Threshold (PPT): The measurements will be conducted by digital hand-held pressure algometer with a rubber tip of approximately 1 cm² (FPX 50, FORCE TEN by Wagner Instruments), increasing pressure will be given perpendicular to the skin . Measurements are taken at five standardized sites. .	12 Weeks postoperative (T2)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: Pressure Pain Threshold	Pressure Pain Threshold (PPT): The measurements will be conducted by digital hand-held pressure algometer with a rubber tip of approximately 1 cm² (FPX 50, FORCE TEN by Wagner Instruments), increasing pressure will be given perpendicular to the skin . Measurements are taken at five standardized sites. .	12 months postoperative (T3)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: Temporal Summation	Measurement tool is a Frey Filament / monofilament calibrated to 10g. The patient is asked to rate the first touch on an NRS from 0 (no pain at all) to 10 (worst imaginable pain). Then the measurement is repeated once per second (1Hz) for 30seconds on a surface of maximum 1cm2. After the 30 seconds application, the patient is asked to rate the last touch on an NRS. The difference between the last and the first rating is calculated. Fifteen seconds after the test, patients need to rate any ongoing pain sensation on NRS again.	pre operative (T1)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: Temporal Summation	Measurement tool is a Frey Filament / monofilament calibrated to 10g. The patient is asked to rate the first touch on an NRS from 0 (no pain at all) to 10 (worst imaginable pain). Then the measurement is repeated once per second (1Hz) for 30seconds on a surface of maximum 1cm2. After the 30 seconds application, the patient is asked to rate the last touch on an NRS. The difference between the last and the first rating is calculated. Fifteen seconds after the test, patients need to rate any ongoing pain sensation on NRS again.	12 Weeks postoperative (T2)
Other	Potential predictor: Central pain processing: Quantitative Sensory Testing: Temporal Summation	Measurement tool is a Frey Filament / monofilament calibrated to 10g. The patient is asked to rate the first touch on an NRS from 0 (no pain at all) to 10 (worst imaginable pain). Then the measurement is repeated once per second (1Hz) for 30seconds on a surface of maximum 1cm2. After the 30 seconds application, the patient is asked to rate the last touch on an NRS. The difference between the last and the first rating is calculated. Fifteen seconds after the test, patients need to rate any ongoing pain sensation on NRS again.	12 months postoperative (T3)
Other	Potential predictor: psychosocial factor: expectation	Patients' expectations will be assessed using 5 questions adopted from the literature studying the Musculoskeletal Outcomes Data Evaluation and Management System (MODEMS) questionnaire among others.	pre operative (T1)
Other	Potential predictor: psychosocial factor: Pain Catastrophizing scale	The Pain Catastrophizing Scale assesses whether or not there is presence of catastrophic thinking about pain. Thirteen items entail aspects about different thoughts and feelings whilst experiencing pain. Items are scored on a 5-point Likert scale. Higher scores indicate more severe catastrophic thinking about pain. There is a total score and a score for three subscales (e.g. helplessness, magnification and rumination). The included German version showed similar psychometric properties like the original English version.	pre operative (T1)
Other	Potential predictor: psychosocial factor: Pain Catastrophizing scale	The Pain Catastrophizing Scale assesses whether or not there is presence of catastrophic thinking about pain. Thirteen items entail aspects about different thoughts and feelings whilst experiencing pain. Items are scored on a 5-point Likert scale. Higher scores indicate more severe catastrophic thinking about pain. There is a total score and a score for three subscales (e.g. helplessness, magnification and rumination). The included German version showed similar psychometric properties like the original English version.	12 Weeks postoperative (T2)
Other	Potential predictor: psychosocial factor: Pain Catastrophizing scale	The Pain Catastrophizing Scale assesses whether or not there is presence of catastrophic thinking about pain. Thirteen items entail aspects about different thoughts and feelings whilst experiencing pain. Items are scored on a 5-point Likert scale. Higher scores indicate more severe catastrophic thinking about pain. There is a total score and a score for three subscales (e.g. helplessness, magnification and rumination). The included German version showed similar psychometric properties like the original English version.	12 months postoperative (T3)
Other	Potential predictor: psychosocial factor: Perceived Stress Scale	The Perceived Stress Scale (PSS - 10) includes 10 questions and assesses the degree to which life has been experienced as unpredictable, uncontrollable and overloaded in the past months. The questions are answered by "yes" or "no". According to the developers of the questionnaire, perceived stress is a unidimensional construct. The questions are general in nature and therefore the usage for the cohort present in this study is reasonable. The German version showed good psychometric properties (validity and reliability)	pre operative (T1)
Other	Potential predictor: psychosocial factor: Perceived Stress Scale	The Perceived Stress Scale (PSS - 10) includes 10 questions and assesses the degree to which life has been experienced as unpredictable, uncontrollable and overloaded in the past months. The questions are answered by "yes" or "no". According to the developers of the questionnaire, perceived stress is a unidimensional construct. The questions are general in nature and therefore the usage for the cohort present in this study is reasonable. The German version showed good psychometric properties (validity and reliability)	12 Weeks postoperative (T2)
Other	Potential predictor: psychosocial factor: Perceived Stress Scale	The Perceived Stress Scale (PSS - 10) includes 10 questions and assesses the degree to which life has been experienced as unpredictable, uncontrollable and overloaded in the past months. The questions are answered by "yes" or "no". According to the developers of the questionnaire, perceived stress is a unidimensional construct. The questions are general in nature and therefore the usage for the cohort present in this study is reasonable. The German version showed good psychometric properties (validity and reliability)	12 months postoperative (T3)
Other	Potential predictor: psychosocial factor: Illness perception questionnaire	The Illness Perception Questionnaire Revised (IPQ-R) is designed to assess the cognitive and emotional representations of illness. So called illness perceptions are described as patients' cognitions about their illness, which are formed by experiences, provided information and interpretation of symptoms. The IPQ-R is not disease specific and may be used in any group of interest. It assesses 9 dimensions of illness perceptions and includes 3 domains cited by from Lau et al. (1989). The first domain is called illness identity, the second is called the beliefs domain and the third is labelled as the consequence domain. The answers are captured on a 5-point Likert scale from "strongly disagree" to "strongly agree". The clinimetric properties for musculoskeletal pain are reported to be sufficient, but the questionnaire is only tested on a few musculoskeletal disorders.	pre operative (T1)
Other	Potential predictor: psychosocial factor: Illness perception questionnaire	The Illness Perception Questionnaire Revised (IPQ-R) is designed to assess the cognitive and emotional representations of illness. So called illness perceptions are described as patients' cognitions about their illness, which are formed by experiences, provided information and interpretation of symptoms. The IPQ-R is not disease specific and may be used in any group of interest. It assesses 9 dimensions of illness perceptions and includes 3 domains cited by from Lau et al. (1989). The first domain is called illness identity, the second is called the beliefs domain and the third is labelled as the consequence domain. The answers are captured on a 5-point Likert scale from "strongly disagree" to "strongly agree". The clinimetric properties for musculoskeletal pain are reported to be sufficient, but the questionnaire is only tested on a few musculoskeletal disorders.	12 Weeks postoperative (T2)
Other	Potential predictor: psychosocial factor: Illness perception questionnaire	The Illness Perception Questionnaire Revised (IPQ-R) is designed to assess the cognitive and emotional representations of illness. So called illness perceptions are described as patients' cognitions about their illness, which are formed by experiences, provided information and interpretation of symptoms. The IPQ-R is not disease specific and may be used in any group of interest. It assesses 9 dimensions of illness perceptions and includes 3 domains cited by from Lau et al. (1989). The first domain is called illness identity, the second is called the beliefs domain and the third is labelled as the consequence domain. The answers are captured on a 5-point Likert scale from "strongly disagree" to "strongly agree". The clinimetric properties for musculoskeletal pain are reported to be sufficient, but the questionnaire is only tested on a few musculoskeletal disorders.	12 months postoperative (T3)
Other	Potential predictor: Sleep	4 Questions regarding sleep quality, sleep efficiency, sleep disturbance, number of awakenings per night. The first question is transformed from the Pittsburgh Sleep Quality Index (PSQI), for sleep quality and is rated on a 4-point Likert Scale. The question 2 to 3 are formulated by suggestion from the study by Nijs et al. and adapted to shoulder pain by the first author.	pre operative (T1)
Other	Potential predictor: Sleep	4 Questions regarding sleep quality, sleep efficiency, sleep disturbance, number of awakenings per night. The first question is transformed from the Pittsburgh Sleep Quality Index (PSQI), for sleep quality and is rated on a 4-point Likert Scale. The question 2 to 3 are formulated by suggestion from the study by Nijs et al. and adapted to shoulder pain by the first author.	12 Weeks postoperative (T2)
Other	Potential predictor: Sleep	4 Questions regarding sleep quality, sleep efficiency, sleep disturbance, number of awakenings per night. The first question is transformed from the Pittsburgh Sleep Quality Index (PSQI), for sleep quality and is rated on a 4-point Likert Scale. The question 2 to 3 are formulated by suggestion from the study by Nijs et al. and adapted to shoulder pain by the first author.	12 months postoperative (T3)
Other	Global Rating of Change GRoC	GRoC represents an anchor of change, not a true change. GRoC is simple and easy to administer. It is recommended to include an 11-point scale with endpoints at -5 and +5, with -5 = "very much worse", 0 = "no change" and +5 = "completely recovered". The recommendation for the single question asked by the assessor is: "With respect to your shoulder problem, how would you describe yourself now compared to pre-surgery?"	12 Weeks postoperative (T2)
Other	Global Rating of Change GRoC	GRoC represents an anchor of change, not a true change. GRoC is simple and easy to administer. It is recommended to include an 11-point scale with endpoints at -5 and +5, with -5 = "very much worse", 0 = "no change" and +5 = "completely recovered". The recommendation for the single question asked by the assessor is: "With respect to your shoulder problem, how would you describe yourself now compared to pre-surgery?"	12 months postoperative (T3)
Other	Postoperative satisfaction survey	The postoperative satisfaction survey consists different grades of satisfaction. This seems relevant for analyses of the construct. The survey has not been validated in German language and therefore had to be integrated in this study by the first authors translation.	12 months postoperative (T3)
Primary	Western Ontario Rotator Cuff Index (WORC) change from preOP to 12 weeks postOP and preOP to 12months postOP	This 21 - items self-reported questionnaire represents a quality of life measure in rotator cuff pathology. The WORC measures 5 dimensions (pain, sports/leisure, work, daily living, feelings) with 3-6 questions per domain, measured on a 100mm Visual Analogue Scale (VAS). Left endpoint equals "no" and right endpoint equals "extreme". The total WORC score ranges from 0 (best) to 2100 (worst) (21 items x 100mm). The minimal important difference (MID) is calculated at 300mm. The PROM is reported to have positive evidence for 5 psychometric properties; internal consistency, reliability, content validity, hypothesis testing and responsiveness.	pre operative (T1), 12 Weeks postoperative (T2), 12 months postoperative (T3)
Secondary	Constant-Murlex Score change from preOP to 12months postOP	The Constant-Murley Score assesses shoulder function of which 35 % are subjective variables (maximum pain intensity, work, sport/leisure, sleep, pain free height for light work), and 65% are objective variables (range of motion (ROM) and strength measure). A sum score of 100 represents perfect shoulder function, 0 represents no functionality	pre operative (T1), 12 months postoperative (T3)
Secondary	Maximum Pain on Numeric Rating Scale (NRS), change from preOP to 12 weeks postOP and preOP to 12months postOP	Patients are asked to indicate the maximum perceived shoulder pain felt in daily life on an NRS from 0 (no pain at all) to 10 (worst imaginable pain)	pre operative (T1), 12 Weeks postoperative (T2), 12 months postoperative (T3)
Secondary	EQ-5D-5L, Euroqol 5dimensions, 5 levels, Quality of life measure, change from preOP to 12 weeks postOP and preOP to 12months postOP	The research group EuroQol developed the EQ-5D-5L tool "in order to provide a simple, generic measure of health for clinical and economic appraisal". It contains of 5 dimensions: mobility, self-care, usual activities, pain/discomfort and depression/anxiety and 5 levels ranging from no problems, slight problems, moderate problems, severe problems, and extreme problems.	pre operative (T1), 12 Weeks postoperative (T2), 12 months postoperative (T3)
Secondary	Subjective Shoulder Value, change from preOP to 12 weeks postOP and preOP to 12months postOP	The SSV is evaluated by one single standardised question:" What is the overall percent value of your shoulder, if a completely normal shoulder represents 100%?"	pre operative (T1), 12 Weeks postoperative (T2),12 months postoperative (T3)