A biomechanical assessment of superior shoulder translation after reconstruction of anterior glenoid bone defects: The Latarjet procedure versus allograft reconstruction
Author(s)
Type
Journal Article
Abstract
Background: The coracoacromial ligament (CAL) is an important restraint to superior shoulder
translation. The effect of CAL release on superior stability following the Latarjet is unknown;
therefore, our purpose was to compare the effect of two Latarjet techniques and allograft
reconstruction on superior instability.
Materials and Methods: Eight cadaveric specimens were tested on a simulator. Superior translation
was monitored following an axial force in various glenohumeral rotations (neutral, internal, and
external) with and without muscle loading. Three intact CAL states were tested (intact specimen,
30% glenoid bone defect, and allograft reconstruction) and two CAL deficient states (classic
Latarjet (classicLAT) and congruent‑arc Latarjet (congruentLAT)).
Results: In neutral without muscle loading, a significant increase in superior translation occurred
with the classicLAT as compared to 30% defect (P = 0.046) and allograft conditions (P = 0.041).
With muscle loading, the classicLAT (P = 0.005, 0.002) and the congruentLAT (P = 0.018, 0.021)
had significantly greater superior translation compared to intact and allograft, respectively. In
internal rotation, only loaded tests produced significant results; specifically, classicLAT increased
translation compared to all intact CAL states (P < 0.05). In external rotation, only unloaded tests
produced significant results with classicLAT and congruentLAT allowing greater translations
than intact (P ≤ 0.028). For all simulations, the allograft was not significantly different than
intact (P > 0.05) and no differences (P = 1.0) were found between classicLAT and congruentLAT.
Discussion: In most simulations, CAL release with the Latarjet lead to increased superior humeral
translation.
Conclusion: The choice of technique for glenoid bone loss reconstruction has implications on
the magnitude of superior humeral translation. This previously unknown effect requires further
study to determine its clinical and kinematic outcomes.
translation. The effect of CAL release on superior stability following the Latarjet is unknown;
therefore, our purpose was to compare the effect of two Latarjet techniques and allograft
reconstruction on superior instability.
Materials and Methods: Eight cadaveric specimens were tested on a simulator. Superior translation
was monitored following an axial force in various glenohumeral rotations (neutral, internal, and
external) with and without muscle loading. Three intact CAL states were tested (intact specimen,
30% glenoid bone defect, and allograft reconstruction) and two CAL deficient states (classic
Latarjet (classicLAT) and congruent‑arc Latarjet (congruentLAT)).
Results: In neutral without muscle loading, a significant increase in superior translation occurred
with the classicLAT as compared to 30% defect (P = 0.046) and allograft conditions (P = 0.041).
With muscle loading, the classicLAT (P = 0.005, 0.002) and the congruentLAT (P = 0.018, 0.021)
had significantly greater superior translation compared to intact and allograft, respectively. In
internal rotation, only loaded tests produced significant results; specifically, classicLAT increased
translation compared to all intact CAL states (P < 0.05). In external rotation, only unloaded tests
produced significant results with classicLAT and congruentLAT allowing greater translations
than intact (P ≤ 0.028). For all simulations, the allograft was not significantly different than
intact (P > 0.05) and no differences (P = 1.0) were found between classicLAT and congruentLAT.
Discussion: In most simulations, CAL release with the Latarjet lead to increased superior humeral
translation.
Conclusion: The choice of technique for glenoid bone loss reconstruction has implications on
the magnitude of superior humeral translation. This previously unknown effect requires further
study to determine its clinical and kinematic outcomes.
Date Issued
2013-04-02
Date Acceptance
2013-04-02
Citation
International Journal of Shoulder Surgery, 2013, 7 (1), pp.7-13
ISSN
0973-6042
Publisher
Medknow Publications
Start Page
7
End Page
13
Journal / Book Title
International Journal of Shoulder Surgery
Volume
7
Issue
1
Copyright Statement
Creative Commons Attribution Non-Commercial Share Alike License
Subjects
Science & Technology
Life Sciences & Biomedicine
Orthopedics
Surgery
Coracoacromial ligament
dislocation
instability
Latarjet
shoulder
stability
CORACOACROMIAL LIGAMENT
GLENOHUMERAL STABILITY
JOINT
ROTATION
ACROMIOPLASTY
DISLOCATION
Publication Status
Published