Treatment and outcome of anterior cruciate ligament injury: Truth or Consequences

Sammanfattning: The overall aim of the work presented in this thesis was to evaluate the incidence, outcome and consequences within the 1st year of acute ACL injury of the knee.
The KANON-study, a randomized controlled clinical trial comparing surgical and non-surgical treatment after acute ACL injury, was initiated and some results are included in this thesis. 642 subjects with acute knee injury were assessed in order to include 121 subjects in this RCT. Subgroups of the subjects assessed in the KANON-study and a group of amateur soccer players (188) were assessed.
The annual incidence of ACL injury was found to be 81 per 100 000 inhabitants aged 10-64 years. Possibly as many as 50% of those with an acute ACL tear are misdiagnosed at the clinical examination in the acute phase.
More than every second (57%) acutely ACL injured knee had an associated cortical bone depression fracture and almost all had bone marrow lesions (BML) visualized on MRI. A strong independent relationship between cortical bone depression fractures and bone marrow lesion volumes (p<0.001) suggests that a high proportion of ACL injured knees suffer from extensive compressive trauma to the joint cartilage which may, in part, explain the high frequency of osteoarthritis following this injury.
In amateur soccer players, older age, female gender and lower level of competition (division) were associated with worse self-reported physical activity level. Thus, we recommend a clear description of how activity level was administered as well as adjustment for these variables in reports using self-reported activity level as an outcome.
Using state-of-the-art quantitative MRI technology, we assessed the first year development of joint fluid (JF), BML and cartilage morphometry. JF and BML volumes gradually decreased over the first year, although BML was still persistent in 62% of the knees after one year. One year after the ACL injury, a consistent reduction of cartilage volume, cartilage surface area and thickness was found in the trochlea femur, while an increase of cartilage volume and surface area was found in the central medial femur. Surgical ACL reconstruction was directly and significantly related to increased JF volume at 3 and 6 months, BML volume at 6 months, cartilage volume and area in central medial femur, and decreased cartilage surface area in trochlea femur at 1 year after injury.