Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

A cadaveric biomechanical evaluation of anterior posterior compression II injuries. Injury 2023 Mar;54(3):834-840



Pubmed ID




Scopus ID

2-s2.0-85146321045 (requires institutional sign-in at Scopus site)


PURPOSE: Pelvic fractures are associated with high morbidity and often require surgical intervention. An Anterior Posterior Compression (APC) II injury consists of disruption at the pubic symphysis and anterior sacroiliac joint. Studies investigating specific ligamentous contributions would aid in development of novel fixation techniques. The objective of this study is to determine the level of pelvic destabilization from progressive soft tissue disruptions associated with APC II injuries.

METHODS: Six fresh-frozen cadaveric pelvises were dissected of soft tissues, preserving joint capsules and ligaments. Each pelvis was secured in a double-leg stance and joint motion was tracked with the specimens cyclically loaded to 60% body weight. Each specimen was measured in the intact state and again following stepwise destabilization to an APC II injury model (PS: sectioned pubic symphysis, IPS JOINT: PS + ipsilateral anterior sacroiliac, sacrotuberous, sacrospinous ligaments sectioned, IPS LIGS: IPS JOINT + ipsilateral interosseous ligaments sectioned, IPS JOINT+CONT ASI: IPS LIGS + contralateral anterior sacroiliac ligament disruption).

RESULTS: Compared to the intact state, there was a statistically significant increase in movement in the IPS JOINT (ipsilateral 177%, p<0.001; contralateral 46%, p<0.005) and IPS JOINT+CONT ASI (ipsilateral 184%, p<0.002; and contralateral 62%, p<0.002) states bilaterally. No significant change was demonstrated in the PS or IPS LIGS state.

CONCLUSION: Disruption of ipsilateral ligamentous structures destabilized both sacroiliac joints. The interosseous and posterior sacroiliac ligaments provide the majority of stability of the sacroiliac joint and will likely benefit most from surgical stabilization.

LEVEL OF EVIDENCE: mechanism-based reasoning.

Author List

Cardwell MC, Martin JM, Meinerz C, Beck CJ, Wang M, Schmeling GJ


Gregory J. Schmeling MD Vice Chair, Professor in the Orthopaedic Surgery department at Medical College of Wisconsin
Mei Wang PhD Associate Professor in the Orthopaedic Surgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Biomechanical Phenomena
Crush Injuries
Ligaments, Articular
Musculoskeletal Diseases
Pelvic Bones
Sacroiliac Joint