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Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
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Multidirectional instability of the shoulder: a systematic review with a novel classification
Victor Housset1, Sean Wei Loong Ho2, Alexandre Lädermann3,4,5
1Clinique de l'épaule, Clinique Maussins-Nollet, Paris, France.
EFORT Open Reviews
|April 5, 2024
Summary
Multidirectional instability (MDI) of the shoulder lacks a consensus definition, hindering diagnosis and treatment. This review proposes a novel classification system to better categorize MDI subtypes based on trauma and hyperlaxity.
Area of Science:
- Orthopedics
- Sports Medicine
- Shoulder Surgery
Background:
- Multidirectional instability (MDI) of the shoulder encompasses various instabilities, leading to diagnostic and therapeutic challenges due to a lack of evidence-based consensus.
- Current definitions and diagnostic criteria for MDI exhibit significant heterogeneity among studies.
Purpose of the Study:
- To address the lack of consensus and heterogeneity in defining multidirectional instability (MDI) of the shoulder.
- To propose a novel classification system for MDI subtypes to improve diagnostic accuracy and clinical understanding.
Main Methods:
- A systematic literature search was conducted using PubMed Medline and Embase databases.
- Keywords included "Glenohumeral joint," "Shoulder," "Multidirectional," and "Instability."
- Sixty-eight publications meeting specific inclusion criteria were analyzed.
Main Results:
- High heterogeneity was observed in MDI definitions, with variations in considering trauma (46%), exclusion of labral/bony injuries (37%), and the number of unstable directions (global vs. two directions).
- Only 22% of studies defined MDI as global instability, while 41% considered instability in two directions, including the inferior direction.
- A novel AB classification is proposed, incorporating traumatic etiology and hyperlaxity for subdividing MDI.
Conclusions:
- Multidirectional instability (MDI) is characterized by symptomatic shoulder joint instability in two or more directions.
- A comprehensive classification system considering predisposing trauma and hyperlaxity is crucial for precise assessment of MDI subtypes.
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