Bone-ingrowth hip prostheses in asymptomatic patients: radiographic features

Area of Science:

• Orthopedic Surgery
• Radiology
• Biomaterials Science

Background:

• Bone-ingrowth femoral prostheses are designed for biological fixation.
• Understanding radiographic changes is crucial for accurate interpretation.
• Previous studies on cemented prostheses link certain radiographic findings to failure.

Purpose of the Study:

• To review radiographic changes in asymptomatic bone-ingrowth femoral prostheses.
• To determine if these radiographic alterations correlate with clinical failure.
• To differentiate radiographic findings in bone-ingrowth versus cemented prostheses.

Main Methods:

• Retrospective review of radiographic images from 85 bone-ingrowth femoral prostheses.
• Analysis of 77 asymptomatic patients with an average follow-up of 21.8 months.
• Documentation and frequency assessment of specific radiographic alterations.

Main Results:

• Common radiographic alterations include proximal medial neck remodeling (stress shielding) (98%) and prosthesis-bone interface lucency (79%).
• Other frequent findings: endosteal sclerosis (36%), heterotopic bone (24%), and cortical thickening (12%).
• No radiographic findings were associated with clinical failure in this cohort.

Conclusions:

• Radiographic alterations are frequent in asymptomatic bone-ingrowth femoral prostheses.
• These findings differ from those in cemented prostheses, where they often signify failure.
• Awareness of these specific radiographic changes prevents misinterpretation and unnecessary clinical concern.