Primary cam morphology; bump, burden or bog-standard? A concept analysis

Area of Science:

• Orthopedics
• Sports Medicine
• Radiology

Background:

• Cam morphology is a common hip abnormality and a risk factor for hip pain and osteoarthritis.
• Secondary cam morphology arises from existing hip disease, while primary cam morphology lacks a clear disease association.
• Primary cam morphology likely develops during skeletal maturation due to physiological responses to load.

Purpose of the Study:

• To introduce and clarify the concept of primary cam morphology.
• To propose a new conceptual and operational definition for primary cam morphology.
• To differentiate primary cam morphology from secondary cam morphology.

Main Methods:

• A rigorous eight-step concept analysis was performed on relevant literature.
• Articles reporting risk factors for primary cam morphology were included.
• Articles focusing on secondary cam morphology were excluded.

Main Results:

• A new conceptual and operational definition for primary cam morphology was proposed, including five defining attributes: tissue type, size, site, shape, and ownership.
• Primary cam morphology is characterized as a cartilage or bony prominence at the femoral head-neck junction, altering the femoral head's shape.
• This morphology is frequently observed in asymptomatic male athletes, often affecting both hips, and is commonly measured using the alpha angle via imaging.

Conclusions:

• The study introduces and clarifies primary cam morphology with a novel definition.
• Several aspects of primary cam morphology, including its taxonomy, terminology, and operationalization, require further expert consensus.
• A unified understanding of primary cam morphology is needed to accurately describe its prevalence and potential clinical significance in athletic populations.