Marginal impaction as a determinant of functional outcome in acetabular fractures involving the posterior wall

Background
Several variables have been accused for the poor functional results following posterior wall fractures. The authors conducted this study to identify the relative risk of marginal impaction fractures for developing a poor result.
Patients
Cases of acetabular fractures with posterior wall components associated with marginal impaction were compared with the same pattern of fractures without marginal impaction. Patients with recognized variables that may affect the outcome were excluded, including femoral head injuries, nonanatomic reductions, avascular necrosis, deep infection, heterotopic ossification grade III and IV, obesity, and problematic lower limb injuries. Marginal impaction injuries were openly elevated and autografted from the greater trochanter, followed by rigid internal fixation for early postoperative mobilization. A total of 40 cases were excluded for the aforementioned reasons, leaving 27 cases of marginal impaction and 38 cases of control. The average period of follow-up was 35.7 months.
Results
Based on the Merle D’Aubigné and Postel functional score, the marginal impaction grafting group revealed 11 (40.7%) excellent, 7 (25.9%) very good, 6 (22.2%) good, one (3.8%) fair, and two (7.4%) poor results. However, the control group showed 16 (42.1%) excellent, 10 (26.3%) very good, 8 (21.1%) good, one (2.6%) fair, and three (7.9%) poor results.
Conclusion
Taking marginal impaction as a sole variable, adequate grafting and fixation of the osteochondral fragment did not seem to make a statistically significant difference (=0.9) regarding the end functional results of these patients.