Purpose: This study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and... Show morePurpose: This study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and assess the reproducibility of these tasks. Methods: 120 Asymptomatic participants aged 18-70 years each performed 10 JPR-tasks. Both contralateral and ipsilateral JPR-tasks were evaluated on accuracy of JPR under active-and passive conditions at two levels within the shoulder forward flexion trajectory. Each task was performed three times. In a subgroup of 40 participants, the reproducibility of JPR-tasks was assessed one week after initial measurement. Reproducibility of JPR-tasks was evaluated by both reliability (intra-class correlation coefficients (ICC's)) and agreement (standard error of measurement (SEM)) measures. Results: Age was not associated with increased JPR-errors for any of the contralateral or ipsilateral JPR-tasks. ICC's ranged between 0.63 and 0.80 for contralateral JPR-tasks, and from 0.32 to 0.48 for ipsilateral tasks, except for one ipsilateral task where the reliability was similar to contralateral tasks (0.79). The SEM was comparable and small for all JPR-tasks, ranging between 1.1 and 2.1. Conclusion: No age-related decline in JPS of the asymptomatic shoulder was found, and good agreement between test and re-test measurements for all JPR-tasks as indicated by the small SEM. Show less
Geurkink, T.H.; Overbeek, C.L.; Marang-van de Mheen, P.J.; Nagels, J.; Nelissen, R.G.H.H.; Groot, J.H. de 2023
PurposeThis study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and... Show morePurposeThis study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and assess the reproducibility of these tasks.Methods120 Asymptomatic participants aged 18–70 years each performed 10 JPR-tasks. Both contralateral and ipsilateral JPR-tasks were evaluated on accuracy of JPR under active- and passive conditions at two levels within the shoulder forward flexion trajectory. Each task was performed three times. In a subgroup of 40 participants, the reproducibility of JPR-tasks was assessed one week after initial measurement. Reproducibility of JPR-tasks was evaluated by both reliability (intra-class correlation coefficients (ICC’s)) and agreement (standard error of measurement (SEM)) measures.ResultsAge was not associated with increased JPR-errors for any of the contralateral or ipsilateral JPR-tasks. ICC’s ranged between 0.63 and 0.80 for contralateral JPR-tasks, and from 0.32 to 0.48 for ipsilateral tasks, except for one ipsilateral task where the reliability was similar to contralateral tasks (0.79). The SEM was comparable and small for all JPR-tasks, ranging between 1.1 and 2.1.ConclusionNo age-related decline in JPS of the asymptomatic shoulder was found, and good agreement between test and re-test measurements for all JPR-tasks as indicated by the small SEM. Show less
Geurkink, T.H.; Overbeek, C.L.; Marang-van de Mheen, P.J.; Nagels, J.; Nelissen, R.G.H.H.; Groot, J.H. de 2023
Purpose: This study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and... Show morePurpose: This study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and assess the reproducibility of these tasks.Methods: 120 Asymptomatic participants aged 18-70 years each performed 10 JPR-tasks. Both contralateral and ipsilateral JPR-tasks were evaluated on accuracy of JPR under active-and passive conditions at two levels within the shoulder forward flexion trajectory. Each task was performed three times. In a subgroup of 40 participants, the reproducibility of JPR-tasks was assessed one week after initial measurement. Reproducibility of JPR-tasks was evaluated by both reliability (intra-class correlation coefficients (ICC's)) and agreement (standard error of measurement (SEM)) measures. Results: Age was not associated with increased JPR-errors for any of the contralateral or ipsilateral JPR-tasks. ICC's ranged between 0.63 and 0.80 for contralateral JPR-tasks, and from 0.32 to 0.48 for ipsilateral tasks, except for one ipsilateral task where the reliability was similar to contralateral tasks (0.79). The SEM was comparable and small for all JPR-tasks, ranging between 1.1 and 2.1.onclusion: No age-related decline in JPS of the asymptomatic shoulder was found, and good agreement between test and re-test measurements for all JPR-tasks as indicated by the small SEM. Show less
AimsThis study aimed to investigate the estimated change in primary and revision arthroplasty rate in the Netherlands and Denmark for hips, knees, and shoulders during the COVID- 19 pandemic in... Show moreAimsThis study aimed to investigate the estimated change in primary and revision arthroplasty rate in the Netherlands and Denmark for hips, knees, and shoulders during the COVID- 19 pandemic in 2020 (COVID-period). Additional points of focus included the comparison of patient characteristics and hospital type (2019 vs COVID-period), and the estimated loss of quality-adjusted life years (QALYs) and impact on waiting lists.MethodsAll hip, knee, and shoulder arthroplasties (2014 to 2020) from the Dutch Arthroplasty Reg-ister, and hip and knee arthroplasties from the Danish Hip and Knee Arthroplasty Registries, were included. The expected number of arthroplasties per month in 2020 was estimated using Poisson regression, taking into account changes in age and sex distribution of the general Dutch/Danish population over time, calculating observed/expected (O/E) ratios. Country-specific proportions of patient characteristics and hospital type were calculated per indication category (osteoarthritis/other elective/acute). Waiting list outcomes including QALYs were estimated by modelling virtual waiting lists including 0%, 5% and 10% extra capacity.ResultsDuring COVID-period, fewer arthroplasties were performed than expected (Netherlands: 20%; Denmark: 5%), with the lowest O/E in April. In the Netherlands, more acute indica-tions were prioritized, resulting in more American Society of Anesthesiologists grade III to IV patients receiving surgery. In both countries, no other patient prioritization was present. Relatively more arthroplasties were performed in private hospitals. There were no clinically relevant differences in revision arthroplasties between pre- COVID and COVID-period. Esti-mated total health loss depending on extra capacity ranged from: 19,800 to 29,400 QALYs (Netherlands): 1,700 to 2,400 QALYs (Denmark). With no extra capacity it will take > 30 years to deplete the waiting lists.ConclusionThe COVID- 19 pandemic had an enormous negative effect on arthroplasty rates, but more in the Netherlands than Denmark. In the Netherlands, hip and shoulder patients with acute indications were prioritized. Private hospitals filled in part of the capacity gap. QALY loss due to postponed arthroplasty surgeries is considerable. Show less
Purpose: Acromegalic arthropathy is a well-known phenomenon, occurring in most patients regardless of disease status. To date, solely hips, knees, hands, and spinal joints have been... Show morePurpose: Acromegalic arthropathy is a well-known phenomenon, occurring in most patients regardless of disease status. To date, solely hips, knees, hands, and spinal joints have been radiographically assessed. Therefore, this study aimed to assess the prevalence of joint symptoms and radiographic osteoarthritis (OA) of new, and established peripheral joint sites in well-controlled acromegaly. Methods: Fifty-one acromegaly patients (56% female, mean age 64 +/- 12 years) in long-term remission for 18.3 years (median, IQR 7.2-25.4) were included. Nineteen patients currently received pharmacological treatment. Self-reported joint complaints were assessed using standardized interviews. Self-reported disability of the upper and lower limbs, and health-related quality of life (HR-QoL) were evaluated using validated questionnaires. Radiographic OA [defined as Kellgren & Lawrence (KL) >= 2] was scored using (modified) KL methods. Results: Radiographic signs of OA were present in 46 patients (90.2%) with >= 2 joints affected in virtually all of these patients (N = 44; 95.7%). Radiographic MTP1 OA was as prevalent as radiographic knee OA (N = 26, 51.0%), and radiographic glenohumeral OA was similarly prevalent as hip OA [N = 21 (41.2%) vs. N = 24 (47.1%)]. Risk factors for radiographic glenohumeral OA were higher pre-treatment IGF-1 levels [OR 1.06 (1.01-1.12), P = 0.021], and current pharmacological treatment [OR 5.01 (1.03-24.54), P = 0.047], whereas no risk factors for MTP1 joint OA could be identified. Conclusion: Similar to previously-assessed peripheral joints, clinical and radiographic arthropathy of the shoulder and feet were prevalent in controlled acromegaly. Further studies on adequate management strategies of acromegalic arthropathy are needed. Show less
Overbeek, C.; Kolk, A.; Witte, P.B. de; Nagels, J.; Nelissen, R.G.H.; Groot, J. de 2022
Background: Patients with Subacromial Pain Syndrome show reduced co-contraction of the teres major during abduction. Consequent insufficient humeral depressor function may contribute to painful... Show moreBackground: Patients with Subacromial Pain Syndrome show reduced co-contraction of the teres major during abduction. Consequent insufficient humeral depressor function may contribute to painful irritation of subacromial tissues and offers a potential target for therapy. A crucial gap in knowledge is whether the degree of teres major co-contraction in these patients is influenced by pain itself. To gain insight into this matter, we assessed whether relief of subacromial pain with local analgesics leads to increased adductor co-contraction in 34 patients with subacromial pain. Methods: In a single-arm interventional study with 34 patients, electromyographic activity of the latissimus dorsi, pectoralis major, teres major and deltoid was assessed during isometric force tasks in 24 directions before and after subacromial Lidocaine injection. Co-contraction was quantified using the activation ratio; range [-1 (sole antagonistic activation, i.e. co-contraction) to 1 (sole agonistic activation)]. Findings: There were no changes in activation ratio of the teres major after the intervention (Z-score:-0.6, p = 0.569). The activation ratio of the latissimus dorsi increased to 0.38 (quartiles: 0.13-0.76), indicating decreased co-contraction (Z-score: -2.0, p = 0.045). Interpretation: Subacromial analgesics led to a decrease in co-contraction of the latissimus dorsi, whereas no change in the degree of teres major co-contraction was observed. This study shows that decreased teres major co contraction in patients with subacromial pain, likely is not the consequence of pain itself, opening a window for physical therapy with training of teres major co-contraction to reduce subacromial irritation and pain. Level of evidence: Level II treatment study. Show less
Kolk, A.; Overbeek, C.L.; Witte, P.B. de; Canete, A.N.; Reijnierse, M.; Nagels, J.; ... ; Groot, J.H. de 2021
Background: Conflicting theories exist about the underlying cause of chronic subacromial pain in the middle-aged population. We aim to improve our understanding of kinematics and muscle activation... Show moreBackground: Conflicting theories exist about the underlying cause of chronic subacromial pain in the middle-aged population. We aim to improve our understanding of kinematics and muscle activation in subacromial pain syndrome to provide insight in its pathophysiology. Methods: In a cross-sectional comparison of 40 patients with subacromial pain syndrome and 30 asymptomatic controls, three-dimensional shoulder kinematics and electromyography-based co-contraction in 10 shoulder muscles were independently recorded. Glenohumeral and scapulothoracic kinematics were evaluated during abduction and forward flexion. Co-contraction was expressed as an activation ratio, specifying the relative agonistic and antagonistic muscle activity in each muscle. Findings: During abduction and forward flexion, the contribution of glenohumeral motion to elevation and glenohumeral external rotation was lower in subacromial pain syndrome (at 1200 abduction: - 9 degrees, 95% CI -14 degrees- -3 degrees; and - 8 degrees, 95% CI -13 degrees -3 degrees, respectively), and was compensated by more scapulothoracic motion. The pectoralis major's activation ratio was significantly lower (Z-score: -2.657, P = 0.008) and teres major's activation ratio significantly higher (Z-score: -4.088, P < 0.001) in patients with subacromial pain syndrome compared to the control group. Interpretation: Reduced glenohumeral elevation and external rotation in subacromial pain syndrome coincided with less teres major antagonistic activity during elevation. These biomechanical findings provide a scientific basis for intervention studies directed at stretching exercises to reduce glenohumeral stiffness in the treatment of subacromial pain syndrome, and teres major strengthening to improve humeral head depressor function. Show less
Kolk, A.; Zwaal, P. van der; Thomassen, B.J.W.; Kamp, E.W.C. van de; Stijnen, T.; Groot, J.H. de; Nelissen, R.G.H.H. 2018
The Subacromial Impingement Syndrome (SIS) is the most prevalent disorder of the shoulder in primary health care. Acromionplasty, as the main surgical treatment of SIS, is one of the most performed... Show moreThe Subacromial Impingement Syndrome (SIS) is the most prevalent disorder of the shoulder in primary health care. Acromionplasty, as the main surgical treatment of SIS, is one of the most performed orthopedic surgeries. However, its results are highly variable. Possibly, there are different etiologic subgroups of patients, that might need specific treatment approaches. Several etiologic mechanisms have been described for subacromial narrowing or __impingement__: i.e. 1) structural causes, including acromion shape, subacromial bony spurs, osteophytes; 2) narrowing of the subacromial space due to humerus cranialisation in patients with (micro)instability, or scapular dyskinesia; 3) intrinsic mechanisms such as primary degenerative tendinopathy of the rotator cuff. The aim of this thesis is to unravel the clinical entity __Subacromial Impingement Syndrome__ and to develop methods for identifying distinct etiological patient subgroups that need specific diagnostics and treatment strategies. To this end, we explore the terminological problems and opinions on the main characteristics of SIS amongst international health practitioners, study the prevalence of previously reported etiologic mechanisms in patients with SIS symptoms, develop clinical and biomechanical methods to evaluate and categorize patients with SIS symptoms in diagnostic subgroups, and compare treatment outcomes in trials and follow-up studies. Show less
Suarez, D.R.; Valstar, E.R.; Rozing, P.M.; Keulen, F. van 2013
Pati_nten met een degeneratieve ruptuur van de rotatorcuff vormen een uitdagend probleem voor de behandeld specialist in de besluitvorming met betrekking tot in de behandelstrategie. De opzet van... Show morePati_nten met een degeneratieve ruptuur van de rotatorcuff vormen een uitdagend probleem voor de behandeld specialist in de besluitvorming met betrekking tot in de behandelstrategie. De opzet van dit proefschrift was om beter inzicht te cre_ren in de evaluatie, klinische uitkomst en chirurgische behandeling van degeneratieve rotatorcuffrupturen. In Hoofdstuk 3 wordt de overeenstemming in de beoordeling van de Geometrische Classificatie van cuffrupturen door ervaren beoordelaars onderzocht met behulp van MR beeldvorming met artrografie. In Hoofdstuk 4 wordt een nieuwe methode ge_ntroduceerd om pati_nten met een symptomatische cuffruptuur te onderscheiden van mensen met een asymptomatisch ruptuur middels de kwalificatie van de adductor co-activatie tijdens schouderabductie. In Hoofdstuk 5 werd de associatie onderzocht van de ernst van de ziekte activiteit van reumatoide arthritis en kraakbeenschade, rotatorcuffrupturen en opwaartse migratie van de schouderkop. In Hoofdstuk 6 werd een gerandomiseerde studie uitgevoerd naar de klinische resultaten van een volledig artroscopische versus mini-open behandeling van rotatorcuffrupturen bij 100 pati_nten. In Hoofdstuk 7 werden de klinische uitkomsten en structurele integriteit op postoperatieve MRI onderzocht van volledig artroscopische behandeling van subscapularispeesr upturen. Het doel van Hoofdstuk 8 was de introductie en evaluatie van een nieuwe artroscopische techniek voor de behandeling van massieve cuffrupturen. In Hoofdstuk 9 werd de grootste serie uit de orthopaedische literatuur beschreven van teres major peestransposities. Show less
Patients suffering tendon tears in the glenohumeral cuff muscles show activation of muscles which pull the arm downwards during arm elevation tasks. This so-called co-activation deviates from... Show morePatients suffering tendon tears in the glenohumeral cuff muscles show activation of muscles which pull the arm downwards during arm elevation tasks. This so-called co-activation deviates from healthy controls and is triggered by pain. Goal of this thesis was to demonstrate that deviating muscle activation in patients with glenohumeral cuff tears is related to shoulder instability. We hypothesized that they are compensatory for lost glenohumeral cuff functions, and restrict arm functionality. Cuff-tear simulations using a musculoskeletal model and an experimental arm loading protocol showed increased deltoid activation to compensate lost elevation moments, which jeopardizes glenohumeral stability. Activation of muscles pulling down the humeral head is required to compensate lost stability, which is counterproductive for arm elevation. There is a conflict between stability and mobility. This conflict can be solved by a tendon transfer of the teres major, which demonstrated shoulder function improvement and pain decrease. The concept of compensatory muscle activation provide insight in the underlying mechanisms of patients suffering glenohumeral cuff tears and potentially can be used, also at early symptoms like in impingement, as a diagnostic instrument or it can be applied in new treatment strategies. Show less
We hypothesized that shoulder pain, caused by rheumatoid arthritis (RA), can lead to disuse of the affected shoulder joint. In addition to the structural changes caused by rotator cuff tears,... Show moreWe hypothesized that shoulder pain, caused by rheumatoid arthritis (RA), can lead to disuse of the affected shoulder joint. In addition to the structural changes caused by rotator cuff tears, tendonitis or synovitis disuse may play an important role in the aetiology of fatty degeneration (FD) of the rotator cuff muscles. This FD may induce proximal migration due to shoulder muscle force imbalance, causing even more pain due to subacromial impingement. FD is thought irreversible, even when the underlying pathology was treated. Early referral and treatment of shoulder involvement of rheumatoid disease may protect the rheumatoid shoulder from this downward spiral. It is of great importance to screen rheumatoid arthritis patients for shoulder joint involvement at an early stage. The use of the Upward migration Index to assess proximal migration can be used reliably to screen for the presence of rotator degeneration. In order to quantify fatty degeneration we advocate using the Mean Muscle Density measured on CT-images. We underline the importance of these measurements as they were strongly correlated to shoulder pain and functional loss. Measurement of proximal migration in an early stage can therefore play an important role in the initiation of functional and medicinal treatment of RA and may present patients with better possible outcome providing that shoulder surgery is indicated. Show less
