Hyperextension injuries of the knee: do patterns of bone bruising predict soft tissue injury?

OBJECTIVE: To establish whether patterns of soft tissue injury following knee hyperextension are associated with post-traumatic 'bone bruise' distribution. MATERIALS AND METHODS: Patients with a knee MRI within one year of hyperextension injury were identified at our institution over a 7 year period. MRIs, plain radiographs and clinical details of these patients were reviewed. RESULTS: Twenty-five patients were identified (median time from injury to MRI = 24 days). The most common sites of bone bruising were the anteromedial tibial plateau (48%) and anterolateral tibial plateau (44%). There were high rates of injury to the posterior capsule (52%), ACL (40%) and PCL (40%) but lower rates of injury to the menisci (20%), medial and lateral collateral ligaments (16%) and posterolateral corner (16%). Anterior tibial plateau oedema and rupture of the posterior capsule predicted cruciate ligament injury [OR = 10.5 (p = 0.02) and 24.0 (p = 0.001) respectively]. Whilst anterolateral tibial plateau oedema strongly predicted PCL injury [OR = 26.0, p = 0.003], ACL injury was associated with a variable pattern of bone bruising. Meniscal injury was unrelated to the extent or pattern of bone bruising. 5 out of 8 patients with a 'double sulcus' on the lateral radiograph had ACL injury. The presence of a double sulcus showed significant association with anteromedial kissing contusions (OR = 7.8, p = 0.03). CONCLUSIONS: Following knee hyperextension, bone bruising patterns may be associated with cruciate ligament injury. Other structures are injured less frequently and have weaker associations with bone bruise distribution. The double sulcus sign is a radiographic marker that confers a high probability of ACL injury.

Acute respiratory distress syndrome related to influenza A H1N1 infection: correlation of pulmonary computed tomography findings to extracorporeal membrane oxygenation treatment and clinical outcome.

PURPOSE: The aim of the present study was to correlate computed tomography appearances with clinical severity and outcome using a total lung disease (TLD) score in patients with acute respiratory distress syndrome (ARDS) related to influenza A H1N1 infection. MATERIALS AND METHODS: Chest computed tomographic scans of 33 patients admitted in the intensive care unit with ARDS related to influenza A H1N1 were retrospectively reviewed. Total lung disease was calculated from the combined extent of consolidation (TLC) and ground glass (TLGG) in the anterior, middle, and posterior segments of the lungs at 3 different levels (apex, hila, and base) using the method described by Goodman et al (Radiology. 213:545-552;1999). Total lung disease, TLC, and TLGG were statistically correlated with demographic characteristics, requirement for extracorporeal membrane oxygenation (ECMO) treatment, and patient outcome. RESULTS: Total lung disease is higher in patients who require ECMO treatment (P = .016). It is significantly higher (P = .003) in the posterior segments and significantly lower (P = .0001) in the anterior segments compared with TLGG. Total consolidation significantly increases (P = .0001), whereas TLGG significantly decreases (P = .0001) from the anterior toward the posterior segments. There is also a significant increase in TLD (P = .0001), TLC (P = .0001), and TLGG (P = .004) from the apices to the lung bases. There is a negative correlation between TLD and age (P = .01), and TLGG and body mass index (P = .014). Total consolidation is higher (P = .013) and TLGG is lower (P = .012) in patients with a body mass index greater than 30 kg/m(2). CONCLUSION: A greater extent of air-space disease in ARDS related to influenza A H1N1 infection is associated with progression to ECMO treatment and, therefore, clinical severity. The extent of total air-space disease is greater in younger patients, and obesity is related to a more extensive consolidation.