Objectives. The bony shoulder stability ratio (BSSR) allows for quantification of the bony stabilisers in vivo. We aimed to biomechanically validate the BSSR, determine whether joint incongruence affects the stability ratio (SR) of a shoulder model, and determine the correct parameters (glenoid concavity versus humeral head radius) for calculation of the BSSR in vivo. Methods. 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. Results. The experimental SR is comparable with the calculated SR (mean difference 10%, . sd. 8%; relative values). The experimental incongruence study observed almost no differences (2%, . sd. 2%). The calculated SR on the basis of the socket concavity radius is superior in predicting the experimental SR (mean difference 10%, . sd. 9%) compared with the calculated SR based on the plastic ball radius (mean difference 42%, . sd. 55%). Conclusion. The present biomechanical investigation confirmed the validity of the BSSR. Incongruence has no significant effect on the SR of a shoulder model. In the event of an incongruent system, the calculation of the BSSR on the basis of the glenoid concavity radius is recommended. Cite this article: L. Ernstbrunner, J-D. Werthel, T. Hatta, A. R. Thoreson, H. Resch, K-N. An, P. Moroder. Biomechanical analysis of the effect of
Arthroplasties of the elbow, including total elbow arthroplasty, radial head arthroplasty, distal humeral hemiarthroplasty, and radiocapitellar arthroplasty, are rarely undertaken. This scoping review aims to outline the current research in this area to inform the development of future research. A scoping review was undertaken adhering to the Joanna Briggs Institute guidelines using Medline, Embase, CENTRAL, and trial registries, limited to studies published between 1 January 1990 and 7 February 2021. Endnote software was used for screening and selection, and included randomized trials, non-randomized controlled trials, prospective and retrospective cohort studies, case-control studies, analytical cross-sectional studies, and case series of ten or more patients reporting the clinical outcomes of elbow arthroplasty. The results are presented as the number of types of studies, sample size, length of follow-up, clinical outcome domains and instruments used, sources of funding, and a narrative review.Aims
Methods
We report the clinical results of glenoid osteotomy in patients
with atraumatic posteroinferior instability associated with glenoid
dysplasia. The study reports results in 211 patients (249 shoulders) with
atraumatic posteroinferior instability. The patients comprised 63
men and 148 women with a mean age of 20 years. The posteroinferior
glenoid surface was elevated by osteotomy at the scapular neck.
A body spica was applied to maintain the arm perpendicular to the
glenoid for two weeks postoperatively. Clinical results were evaluated
using the Rowe score and Japan Shoulder Society Shoulder Instability
Score (JSS-SIS); bone union, osteoarthrosis, and articular congruity
were examined on plain radiographs.Aims
Patients and Methods
Radial head arthroplasty (RHA) may be used in the treatment of
non-reconstructable radial head fractures. The aim of this study
was to evaluate the mid-term clinical and radiographic results of
RHA. Between 2002 and 2014, 77 RHAs were implanted in 54 men and 23
women with either acute injuries (54) or with traumatic sequelae
(23) of a fracture of the radial head. Four designs of RHA were
used, including the Guepar (Small Bone Innovations (SBi)/Stryker;
36), Evolutive (Aston Medical; 24), rHead RECON (SBi/Stryker; ten)
or rHead STANDARD (SBi/Stryker; 7) prostheses. The mean follow-up
was 74.0 months (standard deviation (Aims
Patients and Methods
