[BIOMECHANICS STUDY ON ACETABULAR POSTERIOR WALL FRACTURE]

Area of Science:

• Orthopedic Surgery
• Biomechanics
• Trauma Surgery

Background:

• Acetabular posterior wall fractures are common injuries.
• Understanding the biomechanical behavior of different fracture patterns is essential for optimal surgical fixation and patient outcomes.

Purpose of the Study:

• To investigate the experimental biomechanics of acetabular posterior wall fractures.
• To provide a theoretical basis for the clinical treatment of these fractures.

Main Methods:

• Six cadaveric pelvises were used, with simulated superior-posterior and inferior-posterior acetabular wall fractures created.
• Fixation methods included interfragmentary screws with a locking reconstruction plate, and the acetabular tridimensional memory fixation system (ATMFS).
• Biomechanical testing involved loading to 1500 N, with displacement analyzed using digital image correlation technology.

Main Results:

• All internal fixations remained intact, with displacements below the clinically tolerable limit of 2 mm.
• In group A, superior-posterior wall fractures showed significantly higher displacement than inferior-posterior wall fractures.
• In group B, both fixation methods (screws/plate and ATMFS) yielded similar, clinically acceptable displacements, with superior-posterior wall fractures exhibiting higher displacement than inferior-posterior wall fractures.

Conclusions:

• The biomechanical forces acting on the superior-posterior wall of the acetabulum are significantly greater than those on the inferior-posterior wall.
• This disparity in biomechanical effect necessitates distinct clinical considerations for each fracture type.
• Failure to differentiate may contribute to post-operative complications such as reduction loss, femoral head subluxation, and traumatic arthritis.