Aims. This study aims to describe a new method that may be used as a supplement to evaluate
This study aimed to quantify the shoulder kinematics during an apprehension-relocation test in patients with anterior shoulder instability (ASI) and glenoid bone loss using the radiostereometric analysis (RSA) method. Kinematics were compared with the patient’s contralateral healthy shoulder. A total of 20 patients with ASI and > 10% glenoid bone loss and a healthy contralateral shoulder were included. RSA imaging of the patient’s shoulders was performed during a repeated apprehension-relocation test. Bone volume models were generated from CT scans, marked with anatomical coordinate systems, and aligned with the digitally reconstructed bone projections on the RSA images. The glenohumeral joint (GHJ) kinematics were evaluated in the anteroposterior and superoinferior direction of: the humeral head centre location relative to the glenoid centre; and the humeral head contact point location on the glenoid.Aims
Methods
The aim of this study was to evaluate two hypotheses. First,
that disruption of posterior bundle of the medial collateral ligament
(PMCL) has to occur for the elbow to subluxate in cases of posteromedial
rotatory instability (PMRI) and second, that ulnohumeral contact
pressures increase after disruption of the PMCL. Six human cadaveric elbows were prepared on a custom-designed
apparatus which allowed muscle loading and passive elbow motion
under gravitational varus. Joint contact pressures were measured
sequentially in the intact elbow (INTACT), followed by an anteromedial
subtype two coronoid fracture (COR), a lateral collateral ligament (LCL)
tear (COR + LCL), and a PMCL tear (COR + LCL + PMCL).Aims
Materials and Methods
Some surgeons are reluctant to perform a reverse
total shoulder arthroplasty (RTSA) on both shoulders because of concerns
regarding difficulty with activities of daily living post-operatively
as a result of limited rotation of the shoulders. Nevertheless,
we hypothesised that outcomes and patient satisfaction following
bilateral RTSA would be comparable to those following unilateral
RTSA. A single-surgeon RTSA registry was reviewed for patients who underwent
bilateral staged RTSA with a minimum follow-up of two years. A unilateral
RTSA matched control was selected for each shoulder in those patients
undergoing bilateral procedures. The Constant–Murley score (CMS), American
Shoulder and Elbow Surgeons (ASES) score, Subjective Shoulder Values
(SSV), visual analogue scale (VAS) for pain, range of movement and
strength were measured pre- and post-operatively. The mean CMS,
ASES, SSV, VAS scores, strength and active forward elevation were
significantly improved
(all p <
0.01) following each operation in those undergoing bilateral
procedures. The mean active external rotation (p = 0.63 and p =
0.19) and internal rotation (p = 0.77 and p = 0.24) were not significantly
improved. The improvement in the mean ASES score after the first
RTSA was greater than the improvement in its control group (p =
0.0039). The improvement in the mean CMS, ASES scores and active
forward elevation was significantly less after the second RTSA than
in its control group (p = 0.0244, p = 0.0183, and p = 0.0280, respectively).
Pain relief and function significantly improved after each RTSA
in those undergoing a bilateral procedure. Bilateral RTSA is thus a reasonable form of treatment for patients
with severe bilateral rotator cuff deficiency, although inferior
results may be seen after the second procedure compared with the
first. Cite this article:
