Hemiarthroplasty of the hip and dislocation

Area of Science:

• Orthopedic surgery
• Biomedical engineering

Background:

• Subcapital femur neck fractures are common injuries requiring surgical intervention.
• Hip endoprostheses, including monopolar and bipolar designs, are used to treat these fractures.
• Dislocation is a significant complication following hip replacement surgery.

Purpose of the Study:

• To compare the dislocation rates between bipolar and monopolar endoprostheses in patients with subcapital femur neck fractures.
• To evaluate the efficacy of bipolar hip implants in reducing dislocation compared to monopolar implants.

Main Methods:

• Retrospective study of 171 patients with subcapital femur neck fractures (1982-1986).
• Comparison of dislocation rates between four types of endoprostheses: Thompson's Moore's (monopolar), Monk's 'hard top', and Charnley-Hastings' (bipolar).
• Analysis of outcomes based on standard surgical approaches (posterior and direct lateral).

Main Results:

• No statistically significant difference was observed in dislocation rates between monopolar and bipolar endoprostheses.
• Both implant types, when used with standard surgical approaches, demonstrated similar dislocation incidence.

Conclusions:

• Bipolar hip endoprostheses do not offer superior protection against dislocation compared to traditional monopolar devices.
• The choice between monopolar and bipolar endoprostheses may not significantly impact dislocation risk in this patient cohort.