Aims. The Oxford Shoulder Score (OSS) is a 12-item measure commonly used for the assessment of shoulder surgeries. This study explores whether computerized adaptive testing (CAT) provides a shortened, individually tailored questionnaire while maintaining test accuracy. Methods. A total of 16,238 preoperative OSS were available in the National Joint Registry (NJR) for England, Wales, Northern Ireland, the Isle of Man, and the States of Guernsey dataset (April 2012 to April 2022). Prior to CAT, the foundational item response theory (IRT) assumptions of unidimensionality, monotonicity, and local independence were established. CAT compared sequential item selection with stopping criteria set at standard error (SE) < 0.32 and SE < 0.45 (equivalent to reliability coefficients of 0.90 and 0.80) to full-length patient-reported outcome measure (PROM) precision. Results. Confirmatory factor analysis (CFA) for unidimensionality exhibited satisfactory fit with root mean square standardized residual (RSMSR) of 0.06 (cut-off ≤ 0.08) but not with comparative fit index (CFI) of 0.85 or Tucker-Lewis index (TLI) of 0.82 (cut-off > 0.90). Monotonicity, measured by H value, yielded 0.482, signifying good monotonic trends. Local independence was generally met, with Yen’s Q3 statistic > 0.2 for most items. The median item count for completing the CAT
Aims. In patients with a rotator cuff tear, tear pattern and tendon involvement are known risk factors for the development of pseudoparalysis of the shoulder. It remains unclear, however, why similar tears often have very different functional consequences. The present study hypothesizes that individual shoulder anatomy, specifically the moment arms (MAs) of the rotator cuff (RC) and the deltoid muscle, as well as their relative recruitment during shoulder abduction, plays a central role in pseudoparalysis. Materials and Methods. Biomechanical and clinical analyses of the pseudoparalytic shoulder were conducted based on the ratio of the RC/deltoid MAs, which were used to define a novel anatomical descriptor called the Shoulder Abduction Moment (SAM) index. The SAM index is the ratio of the radii of two concentric spheres based on the centre of rotation of the joint. One sphere captures the humeral head (numerator) and the other the deltoid origin of the acromion (denominator). A computational rigid body
Objectives. To date, no study has considered the impact of acromial morphology on shoulder range of movement (ROM). The purpose of our study was to evaluate the effects of lateralization of the centre of rotation (COR) and neck-shaft angle (NSA) on shoulder ROM after reverse shoulder arthroplasty (RSA) in patients with different scapular morphologies. Methods. 3D computer models were constructed from CT scans of 12 patients with a critical shoulder angle (CSA) of 25°, 30°, 35°, and 40°. For each model, shoulder ROM was evaluated at a NSA of 135° and 145°, and lateralization of 0 mm, 5 mm, and 10 mm for seven standardized movements: glenohumeral abduction, adduction, forward flexion, extension, internal rotation with the arm at 90° of abduction, as well as external rotation with the arm at 10° and 90° of abduction. Results. CSA did not seem to influence ROM in any of the models, but greater lateralization achieved greater ROM for all movements in all configurations. Internal and external rotation at 90° of abduction were impossible in most configurations, except in models with a CSA of 25°. Conclusion. Postoperative ROM following RSA depends on multiple patient and surgical factors. This study, based on computer
We retrospectively assessed the value of identifying
impinging osteophytes using dynamic computer
The open Latarjet procedure is a widely used treatment for recurrent anterior instability of the shoulder. Although satisfactory outcomes are reported, factors which influence a patient’s experience are poorly quantified. The aim of this study was to evaluate the effect of a range of demographic factors and measures of the severity of instability on patient-reported outcome measures in patients who underwent an open Latarjet procedure at a minimum follow-up of two years. A total of 350 patients with anterior instability of the shoulder who underwent an open Latarjet procedure between 2005 and 2018 were reviewed prospectively, with the collection of demographic and psychosocial data, preoperative CT, and complications during follow-up of two years. The primary outcome measure was the Western Ontario Shoulder Instability Index (WOSI), assessed preoperatively, at two years postoperatively, and at mid-term follow-up at a mean of 50.6 months (SD 24.8) postoperatively. The secondary outcome measure was the abbreviated version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score. The influence of the demographic details of the patients, measurements of the severity of instability, and the complications of surgery were assessed in a multivariate analysis.Aims
Methods
Patients with recurrent anterior dislocation of the shoulder commonly have an anterior osseous defect of the glenoid. Once the defect reaches a critical size, stability may be restored by bone grafting. The critical size of this defect under non-physiological loading conditions has previously been identified as 20% of the length of the glenoid. As the stability of the shoulder is load-dependent, with higher joint forces leading to a loss of stability, the aim of this study was to determine the critical size of an osseous defect that leads to further anterior instability of the shoulder under physiological loading despite a Bankart repair. Two finite element (FE) models were used to determine the risk of dislocation of the shoulder during 30 activities of daily living (ADLs) for the intact glenoid and after creating anterior osseous defects of increasing magnitudes. A Bankart repair was simulated for each size of defect, and the shoulder was tested under loading conditions that replicate Aims
Patients and Methods
Since long-term outcome of teres major tendon transfer surgery
for irreparable posterosuperior rotator cuff (RC) tears is largely
unknown, the primary aim of this study was to evaluate the long-term
outcome of the teres major transfer. We also aimed to report on
the results of a cohort of patients with a similar indication for
surgery that underwent a latissimus dorsi tendon transfer. In this prospective cohort study, we reported on the long-term
results of 20 consecutive patients with a teres major tendon transfer
for irreparable massive posterosuperior RC tears. Additionally,
we reported on the results of the latissimus dorsi tendon transfer
(n = 19). The mean age was 60 years (47 to 77). Outcomes included
the Constant score (CS), and pain at rest and during movement using
the Visual Analogue Scale (VAS).Aims
Patients and Methods
The aim of this study was to analyse human muscle tissue before
and after rotator cuff repair to look for evidence of regeneration,
and to characterise the changes seen in the type of muscle fibre. Patients were assessed pre-operatively and one year post-operatively
using the Oxford Shoulder Score (OSS) and MRI. The cross-sectional
area and distribution of the type of muscle fibre were assessed
on biopsies, which were taken at surgery and one year post-operatively.
Paired samples from eight patients were analysed. There were three
men and five women with a mean age of 63 years (50 to 73).Aims
Patients and Methods
The bony shoulder stability ratio (BSSR) allows for quantification of the bony stabilisers Four polyethylene balls (radii: 19.1 mm to 38.1 mm) were used to mould four fitting sockets in four different depths (3.2 mm to 19.1mm). The SR was measured in biomechanical congruent and incongruent experimental series. The experimental SR of a congruent system was compared with the calculated SR based on the BSSR approach. Differences in SR between congruent and incongruent experimental conditions were quantified. Finally, the experimental SR was compared with either calculated SR based on the socket concavity or plastic ball radius.Objectives
Methods
Dislocation of the acromioclavicular joint is
a relatively common injury and a number of surgical interventions
have been described for its treatment. Recently, a synthetic ligament
device has become available and been successfully used, however,
like other non-native solutions, a compromise must be reached when
choosing non-anatomical locations for their placement. This cadaveric
study aimed to assess the effect of different clavicular anchorage points
for the Lockdown device on the reduction of acromioclavicular joint
dislocations, and suggest an optimal location. We also assessed
whether further stability is provided using a coracoacromial ligament
transfer (a modified Neviaser technique). The acromioclavicular
joint was exposed on seven fresh-frozen cadaveric shoulders. The
joint was reconstructed using the Lockdown implant using four different
clavicular anchorage points and reduction was measured. The coracoacromial
ligament was then transferred to the lateral end of the clavicle,
and the joint re-assessed. If the Lockdown ligament was secured
at the level of the conoid tubercle, the acromioclavicular joint
could be reduced anatomically in all cases. If placed medial or
2 cm lateral, the joint was irreducible. If the Lockdown was placed
1 cm lateral to the conoid tubercle, the joint could be reduced
with difficulty in four cases. Correct placement of the Lockdown
device is crucial to allow anatomical joint reduction. Even when the
Lockdown was placed over the conoid tubercle, anterior clavicle
displacement remained but this could be controlled using a coracoacromial
ligament transfer. Cite this article:
