Steen L Jensen - Academia.edu (original) (raw)

Papers by Steen L Jensen

Background and purpose — Both medial unicompartmental knee arthroplasties (UKA) and high tibial o... more Background and purpose — Both medial unicompartmental knee arthroplasties (UKA) and high tibial osteotomies (HTO) are reliable treatments for isolated medial knee osteoarthritis. However, both may with time need conversion to a total knee arthroplasty (TKA). We conducted the largest nationwide registry comparison of the survival of TKA following UKA with TKA following HTO. Patients and methods — From the Danish Knee Arthroplasty Registry, aseptic conversions to TKA from UKA and TKA converted from HTO within the period of 1997–2018 were retrieved. The Kaplan–Meier method and the Cox proportional hazards regression were used to estimate the survival and hazard ratio (HR) for revision, considering confounding by indication utilizing propensity-score based inverse probability of treatment weighting (PS-IPTW). Results — PS-IPTW yielded a well-balanced pseudo-cohort (standard mean difference (SMD) < 0.1 for all covariates, except implant supplementation) of 963.8 TKAs following UKA and...

$Research paper thumbnail of No need to use both Disabilities of the Arm, Shoulder and Hand and Constant–Murley score in studies of midshaft clavicular fractures$

Danish medical journal, 2017

Knowledge of how abstracts may be se-lected for medical conferences in an efficient and reliable ... more Knowledge of how abstracts may be se-lected for medical conferences in an efficient and reliable manner is sparse. To improve abstract selection, the Danish Orthopaedic Society implemented the International Society of the Knee (ISK) quality-of-reporting system and visual analogue scale (VAS) scoring for abstract evaluation at its 2014 Annual Congress. We sought to find out if a simple VAS score was more reliable than a multiple-question system for assessment of over-all abstract quality. A total of 214 abstracts were submitted for review. All abstracts were reviewed by 3 reviewers using a VAS score and the ISK score. Of the 214, 71 abstracts were reviewed again 6 months later to estimate intra-rater agreement. The VAS and the ISK score were poorly correlated (r = 0.64), and the ISK score demonstrated a better intra- and interrater agreement (p < 0.001). The VAS scores of all abstracts were more widely distributed than the ISK scores, which clustered around values in the 50-70 ran...

Trials, Jan 27, 2015

BackgroundShoulder pain is the third most common musculoskeletal disorder, often affecting people... more BackgroundShoulder pain is the third most common musculoskeletal disorder, often affecting people¿s daily living and work capacity. The most common shoulder disorder is the subacromial impingement syndrome (SIS) which, among other pathophysiological changes, is often characterised by rotator cuff tendinopathy. Exercise is often considered the primary treatment option for rotator cuff tendinopathy, but there is no consensus on which exercise strategy is the most effective. As eccentric and high-load strength training have been shown to have a positive effect on patella and Achilles tendinopathy, the aim of this trial is to compare the efficacy of progressive high-load exercises with traditional low-load exercises in patients with rotator cuff tendinopathy.Methods/DesignThe current study is a randomised, participant- and assessor-blinded, controlled multicentre trial. A total of 260 patients with rotator cuff tendinopathy will be recruited from three outpatient shoulder departments in...

The Journal of Bone and Joint Surgery, 2003

We studied the stabilising effect of prosthetic replacement of the radial head and repair of the ... more We studied the stabilising effect of prosthetic replacement of the radial head and repair of the medial collateral ligament (MCL) after excision of the radial head and section of the MCL in five cadaver elbows. Division of the MCL increased valgus angulation (mean 3.9 ± 1.5°) and internal rotatory laxity (mean 5.3 ± 2.0°). Subsequent excision of the radial head allowed additional valgus (mean 11.1 ± 7.3°) and internal rotatory laxity (mean 5.7 ± 3.9°). Isolated replacement of the radial head reduced valgus laxity to the level before excision of the head, while internal rotatory laxity was still greater (2.8 ± 2.1°). Isolated repair of the MCL corrected internal rotatory laxity, but a slight increase in valgus laxity remained (mean 0.7 ± 0.6°). Combined replacement of the head and repair of the MCL restored stability completely. We conclude that the radial head is a constraint secondary to the MCL for both valgus displacement and internal rotation. Isolated repair of the ligament is ...

1 Department of Orthopedic Surgery, Herlev Hospital, University of Copenhagen, Denmark; 2 Departm... more 1 Department of Orthopedic Surgery, Herlev Hospital, University of Copenhagen, Denmark; 2 Department of Orthopedics, Karolinska Institutet Danderyds Sjukhus AB, Stockholm, Sweden; 3 Department of Orthopedic Surgery, Aalborg University Hospital, Aalborg, Denmark; 4 Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway. Correspondence (JVR): jevera01@heh.regionh Submitted 2016-10-25. Accepted 2017-02-20.

Acta Orthopaedica, 2020

Reduced survival of total knee arthroplasty after previous unicompartmental knee arthroplasty com... more Reduced survival of total knee arthroplasty after previous unicompartmental knee arthroplasty compared with previous high tibial osteotomy: a propensity-score weighted mid-term cohort study based on 2,133 observations from the Danish Knee Arthroplasty Registry, Acta Orthopaedica,

The Journal of Arthroplasty, 2018

Prior high tibial osteotomy does not affect the survival of total knee arthroplasties-Results fro... more Prior high tibial osteotomy does not affect the survival of total knee arthroplasties-Results from the Danish Knee Arthroplasty Registry

Journal of Shoulder and Elbow Surgery, 2019

Background: The purpose of this study was to compare the short-term survival rate of total stemle... more Background: The purpose of this study was to compare the short-term survival rate of total stemless, metaphyseal fixated, shoulder arthroplasty with that of total stemmed shoulder arthroplasty in the treatment of osteoarthritis. Methods: Data were collected by the national arthroplasty registries in Denmark, Finland, Norway, and Sweden and merged into 1 dataset under the umbrella of the Nordic Arthroplasty Register Association. For the present study, we included all patients with osteoarthritis treated with either stemless (n ¼ 761) or stemmed (n ¼ 4398) shoulder arthroplasty from 2011 to 2016. Results: A total of 21 (2.8%) stemless and 116 (2.6%) stemmed shoulder arthroplasties were revised. The 6-year unadjusted cumulative survival rates were 0.953 for stemless shoulder arthroplasty and 0.958 for stemmed shoulder arthroplasty, P ¼ .77. The most common indication for revision of both arthroplasty types was infection. Five (0.7%) stemless and 16 (0.4%) stemmed shoulder arthroplasties were revised because of loosening of either the glenoid or the humeral component. In the multivariate No institutional review board approval was required for this retrospective study.

Journal of Orthopaedic Surgery and Research, 2018

Background: In a clinical setting, a visual evaluation of post-implant radiographs is often used ... more Background: In a clinical setting, a visual evaluation of post-implant radiographs is often used to assess the restoration of glenohumeral joint anatomy after resurfacing hemiarthroplasty and is a part of the decision-making process, in combination with other parameters, when evaluating patients with inferior clinical results. However, the reliability of this method of visual evaluation has not been reported. The aim of this study was to investigate the inter-and intra-observer agreement among experienced shoulder surgeons assessing overstuffing, implant positioning, and size following resurfacing hemiarthroplasty using plain standardized radiographs. Methods: Six experienced shoulder surgeons independently classified implant inclination, size of the implant and if the joint seemed overstuffed, in 219 cases of post-implant radiographs. All cases were classified twice 3 weeks apart. Only radiographs with an anterior-posterior projection with a freely visible joint space were used. Non-weighted Cohen's kappa values were calculated for each coder pair and the mean used as an estimate of the overall inter-observer agreement. Results: The overall inter-observer agreement for implant size (kappa, 0.48 and 0.41) and inclination angle was moderate in both rounds (kappa, 0.46 and 0.44), but only a fair agreement was found concerning the evaluation for stuffing of the joint (kappa, 0.24 and 0.28). Intra-observer agreement for implant size and stuffing ranged from fair to substantial while the agreement for inclination was moderate to substantial. Conclusions: Our results indicate that a visual evaluation of plain radiographs may be inadequate to evaluate overstuffing, implant positioning, and size following resurfacing hemiarthroplasty using plain standardized radiographs. Future studies may contribute to elucidate whether reliability increases if consensus on clear definitions and standardized methods of evaluation is made.

$Research paper thumbnail of Revision after shoulder replacement for acute fracture of the proximal humerus$

Acta orthopaedica, Jan 28, 2017

Background and purpose - For more than half a century, stemmed hemiarthroplasty (SHA) has been us... more Background and purpose - For more than half a century, stemmed hemiarthroplasty (SHA) has been used in the treatment of comminuted and displaced fractures of the proximal humerus. Reverse shoulder arthroplasty (RSA) has been increasingly popular in cases where it is difficult to obtain satisfactory fixation of the tuberosities. We report revision rates and reasons for revision after shoulder arthroplasty for acute fractures of the proximal humerus. Patients and methods - This study was based on a common dataset from the Nordic Arthroplasty Register Association (NARA), which includes data reported to the national shoulder arthroplasty registries in Denmark, Sweden, and Norway. We included 6,756 shoulder arthroplasties performed for acute fractures between 2004 and 2013. Results - There were 6,112 SHAs (90%) and 565 RSAs (8.4%). The cumulative arthroplasty survival rate after 5 years was 0.96 for both SHA and RSA. The relative risk of revision of RSA was 1.4 (95% CI: 0.9-2.2) with SHA...

Journal of Shoulder and Elbow Surgery, 2016

The Nordic Arthroplasty Register Association was initiated in 2007, and several papers about hip ... more The Nordic Arthroplasty Register Association was initiated in 2007, and several papers about hip and knee arthroplasty have been published. Inspired by this, we aimed to examine the feasibility of merging data from the Nordic national shoulder arthroplasty registries by defining a common minimal data set. A group of surgeons met in 2014 to discuss the feasibility of merging data from the national shoulder registries in Denmark, Norway, and Sweden. Differences in organization, definitions, variables, and outcome measures were discussed. A common minimal data set was defined as a set of variables containing only data that all registries could deliver and where consensus according to definition of the variables could be made. We agreed on a data set containing patient-related data (age, gender, and diagnosis), operative data (date, arthroplasty type and brand), and data in case of revision (date, reason for revision, and new arthroplasty brand). From 2004 to 2013, there were 19,857 primary arthroplasties reported. The most common indications were osteoarthritis (35%) and acute fracture (34%). The number of arthroplasties and especially the number of arthroplasties for osteoarthritis have increased in the study period. The most common arthroplasty type was total shoulder arthroplasty (34%) for osteoarthritis and stemmed hemiarthroplasty (90%) for acute fractures. We were able to merge data from the Nordic national registries into 1 common data set; however, the set of details was reduced. We found considerable differences between the 3 countries regarding incidence of shoulder arthroplasty, age, diagnoses, and choice of arthroplasty type and brand.

Treatment of Elbow Lesions

... Fig. 5. Graphic illustration of load distribution in the fore-arm before and after radial hea... more ... Fig. 5. Graphic illustration of load distribution in the fore-arm before and after radial head excision. Size of arrows approximates the relative forces based on results from several studies Page 5. neither is as efficient as the native interosseous membrane [55, 56]. Tomaino et al. ...

$Research paper thumbnail of Effect of osteosynthesis, primary hemiarthroplasty, and non-surgical management for displaced four-part fractures of the proximal humerus in elderly: a multi-centre, randomised clinical trial$

Trials, 2009

Background: Fractures of the proximal humerus are common injuries and account for 4-5 percent of ... more Background: Fractures of the proximal humerus are common injuries and account for 4-5 percent of all fractures, second only to hip and wrist fractures. The incidence is positively correlated with age and osteoporosis, and is likely to increase. Displaced four-part fractures are among the most severe injuries, accounting for 2-10 percent of proximal humeral fractures. The optimal intervention is disputed. Two previous randomised trials were very small and involved a noticeable risk of bias, and systematic reviews consequently conclude that there is inadequate basis for evidence-based treatment decisions. We aim to compare the effect of osteosynthesis with angle-stable plate with non-surgical management, and the effect of primary hemiarthroplasty with both osteosynthesis and non-surgical management. Methods/Design: We will conduct a randomised, multi-centre, clinical trial including patients from ten national shoulder units within a two-year period. We plan to include 162 patients. A central randomisation unit will allocate patients. All patients will receive a standardised threemonth rehabilitation program of supervised physiotherapy regardless of treatment allocation. Patients will be followed at least one year. The primary outcomes will be the overall score on the Constant Disability Scale, and its pain subscale, measured at 12 months. A blinded physiotherapist will carry out the assessments. Other secondary outcomes are Oxford Shoulder Score, and general health status (Short Form-36).

Journal of Shoulder and Elbow Surgery, 2003

The objective of this study was to evaluate the osseous constraint related to forced forearm exte... more The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation. The osseous stability, expressed as the maximal torque needed for pathologic external forearm rotation, increased from varus to valgus stress (P ϭ .0001) and from 10°to 90°of elbow flexion (P ϭ .012) and also tended to increase from forearm supination to pronation. The work of pathologic external forearm rotation until the point of maximal torque decreased from a maximum in full extension to a minimum at 30°of elbow flexion (P ϭ .03). The elbow in a slightly flexed position, varus stress, and forearm external rotation trauma might be the important biomechanical factors in the posterior elbow dislocation, and they might serve as guidelines during clinical investigation for posterolateral instability.

Journal of Shoulder and Elbow Surgery, 1999

$Research paper thumbnail of A retrospective study of the association between shortening of the clavicle after fracture and the clinical outcome in 136 patients$

Injury, 2011

The purpose of this retrospective study was to examine the association between shortening of the ... more The purpose of this retrospective study was to examine the association between shortening of the clavicle after a united midshaft fracture and clinical outcome. Second, the purpose was to compare the results obtained by conservative treatment with either a figure-of-eight bandage or a simple sling. This study included 136 patients with a united, conservatively treated, midshaft clavicle fracture. Mean age was 35 years (range 15-70 years); mean follow-up time was 55 months (range 24-83 months). The shortening of the clavicle was measured on a radiograph including one antero-posterior view of both clavicles on a single film and defined as the difference between the injured and the contralateral clavicle. The clinical outcome was measured using the Constant-Murley Score. The mean difference in the Constant-Murley Score between the injured and the contralateral shoulder was 7.3, P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001 (95% confidence interval (CI) 5.6; 9.1). Mean shortening of the injured shoulder was 11.6mm, P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001 (95% CI 10.2; 13.0). A shortening of more than 20mm was not associated with a poorer clinical outcome. The results obtained by conservative treatment with either a figure-of-eight bandage or a simple sling showed no difference in shortening or in the Constant-Murley Score. We found that conservative treatment of midshaft clavicle fractures resulted in final shortening and mild reduction of shoulder function. A shortening of 20mm or more was not associated with a poorer clinical outcome. The figure-of-eight bandage and a simple sling were equal treatments of midshaft clavicle fractures.

$Research paper thumbnail of Surgeons agree more on treatment recommendations than on classification of proximal humeral fractures$

BMC Musculoskeletal Disorders, 2012

Background: Orthopaedic surgeons disagree considerably when classifying fractures of the proximal... more Background: Orthopaedic surgeons disagree considerably when classifying fractures of the proximal humerus. However, the clinical implications of low observer agreement remain unclear. The purpose of the study was to compare the agreement on Neer classification with the agreement on treatment recommendations. Methods: We conducted a multi-centre observer-study. Five experienced shoulder surgeons independently assessed a consecutive series of 193 radiographs at two occasions three months apart. All pairs of radiographs were classified according to Neer. Subsequently, the observers were asked to recommend one of three treatment modalities for each case: non-operative treatment, locking plate osteosynthesis, or hemiarthroplasty. Results: At both classification rounds mean kappa-values for inter-observer agreement on treatment recommendations (0.48 and 0.52) were significantly higher than the agreement on Neer classification (0.33 and 0.36) (p < 0.001 at both rounds). The highest mean kappa-values were found for inter-observer agreement on non-surgical treatment (0.59 and 0.55). In 36% (345 out of 965) of observations an observer changed Neer category between first and second classification round. However, in only 34% of these cases (116 out of 345) the observers changed their treatment recommendations. Conclusions: We found a significantly higher agreement on treatment recommendations compared to agreement on fracture classification. The low observer agreement on the Neer classification reported in several observer studies may have less clinical importance than previously assumed. However, inter-observer agreement did not exceed moderate levels.