There are multiple classification systems for glenoid bone loss, including:

Walch Classification

The Walch Classification is a widely used system for categorizing glenoid morphology in glenohumeral osteoarthritis. It was originally described by Walch et al. in 1999 and later modified by Bercik et al. This system classifies glenoid morphology into four types: 

• Type A: The humeral head is centered, with concentric wear and no subluxation. Type A1 has minor central wear, while Type A2 has severe central wear.
• Type B: The humeral head is subluxated posteriorly, with asymmetric wear and a biconcave glenoid. Type B1 has no obvious glenoid erosion, while Type B2 has obvious erosion of the posterior glenoid.
• Type C: The glenoid has retroversion greater than 25°. Type C1 is dysplastic. Type C2 has posterior bone loss and posterior translation of the humeral head.
• Type D: The glenoid has anteversion or the humeral head is subluxated anteriorly by less than 40°.

Sirveaux Favard Classification

The Sirveaux Favard classification system categorizes glenoid wear patterns related to cuff tear arthropathy (CTA) in the vertical plane. It describes the location and severity of superior glenoid bone loss frequently observed in CTA. The classification consists of five types:

• E0: Superior humeral head migration with no glenoid erosion
• E1: Concentric central erosion of the glenoid
• E2: Superior erosion of the glenoid
• E3: Superior erosion of the glenoid that extends inferiorly
• E4: Inferior erosion of the glenoid

This classification system is particularly useful for surgical planning, helping surgeons compensate for superior wear and avoid placing the baseplate in a superiorly tilted position. It's important to note that this classification primarily focuses on the supero-inferior plane and may not fully capture posterior glenoid wear, which is also common and needs to be addressed

The Levigne–Franceschi Classification

The Levigne–Franceschi classification is a radiographic system used to assess the type of glenohumeral joint damage in patients with rheumatoid arthritis (RA). It's used to evaluate the shape of the glenoid fossa and the migration of the humeral head. The classification system is more complex than the Larsen Score, but it provides more metrics for preoperative planning. 

The Levigne–Franceschi classification system divides shoulders into three basic types:

• C: Concentric
• A: Ascendant
• D: Destruction 

Each type is further divided into two subtypes, with or without glenoid erosion. The three main patterns of glenoid involvement in RA are:

• Upward migration: The most common pattern, characterized by a deficient rotator cuff and superior glenoid wear
• Concentric medial migration: Characterized by deficient bone stock and medialization of the humeral head
• Destructive: A destructive pattern of glenoid involvement

Habermeyer Classification

The Habermeyer classification system for assessing glenoid bone loss, particularly regarding inferior tilt and erosion, is based on the relationship between a line drawn from the superior to the inferior glenoid rim and a vertical line at the level of the coracoid. This system helps document inferosuperior bone loss, which might not be fully appreciated using other classifications like Walch's.

• Type 0: The lines are parallel, indicating no significant tilt or erosion.
• Type 1: The lines intersect below the glenoid, suggesting mild inferior tilt and erosion.
• Type 2: The intersection occurs at the level of the glenoid, indicating moderate tilt and erosion.
• Type 3: The intersection is above the coracoid, reflecting severe inferior tilt and erosion.

This classification is valuable in planning surgical interventions to correct glenoid alignment and manage bone loss effectively

Antuna and Seebauer Classification

The Antuna and Seebauer classification is a modified system for describing glenoid wear patterns in shoulder arthritis. It categorizes defects into three main types:

1. Centric (C): Defects are classified as C1 to C4 based on the degree of vault destruction.
2. Eccentric (E): Defects are classified as E1 to E4 based on two factors:
• Percentage of the defect: minimal, <30%, 30-60%, or >60%
• Location: anterior, posterior, etc.
3. Combined (E/C): A combination of centric and eccentric defects

This classification system aims to provide a comprehensive description of glenoid wear patterns, considering both the extent and location of bone loss. It is particularly useful for surgical planning and decision-making in shoulder arthroplasty cases.

References

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