Distribution of Bone Contusion Patterns in Knees with Acute Isolated Posterior Cruciate Ligament Tears.

BACKGROUND

Bone contusions after acute posterior cruciate ligament (PCL) injury are commonly observed on magnetic resonance imaging (MRI), providing insight into potential mechanisms of injury.

PURPOSE: To quantify the size of bone contusions and their locations-lateral tibial plateau (LTP), lateral femoral condyle (LFC), medial tibial plateau (MTP), medial femoral condyle (MFC), and subspinous subregion (SS)-observed on MRI scans of isolated PCL-torn knees acquired within 4 weeks after injury.

STUDY

DESIGN

Cross-sectional study. Level of evidence, 3.

METHODS

We retrospectively reviewed the clinic notes, operative notes, and imaging of 72 patients (55 men and 17 women) with a grade 2 or 3 primary isolated PCL tear, without any fractures, meniscal tears, or other knee ligament tears, whose MRI scans were obtained within 4 weeks of the injury. The location (LTP, LFC, MTP, MFC, and SS), combined number of compartments, and volume of the bone contusion were recorded based on the MRI Osteoarthritis Knee Score (MOAKS) system-a standardized semi-quantitative mapping technique.

RESULTS

Contusions were observed in 59 of 72 (81.9%) patients. According to the MOAKS system, areas with a high frequency of bone contusion were anterior SS (30; 41.7%), anterior LTP (26; 36.1%), anterior MTP (24; 33.3%), and posterior LFC (23; 31.9%). Female patients showed significantly higher incidence of bone contusion than male patients in the posterior LTP (P = .024), anterior LFC (P = .017), posterior LFC (P = .006), total MFC (P < .001), and posterior SS (P = .039).

CONCLUSION

Bone contusion was observed in most patients with acute isolated PCL rupture. The most common contusion locations observed were anterior SS, anterior LTP, anterior MTP, and posterior LFC. Female patients demonstrated a greater prevalence and extent of bone contusions compared with their male counterparts.