Health technology assessment of magnetic resonance imaging of the knee

Prevalence of abnormal findings in 230 knees of asymptomatic adults using 3.0 T MRI

OBJECTIVE

To identify abnormalities in asymptomatic sedentary individuals using 3.0 Tesla high-resolution MRI.

MATERIALS AND METHODS

The cohort comprised of 230 knees of 115 uninjured sedentary adults (51 males, 64 females; median age: 44 years). All participants had bilateral knee 3.0 T MRIs. Two senior musculoskeletal radiologists graded all intraarticular knee structures using validated scoring systems. Participants completed Knee Injury and Osteoarthritis Outcome Score questionnaires at the time of the MRI scan.

RESULTS

MRI showed abnormalities in the majority (97%) of knees. Thirty percent knees had meniscal tears: horizontal (23%), complex (3%), vertical (2%), radial (2%) and bucket handle (1%). Cartilage and bone marrow abnormalities were prevalent at the patellofemoral joint (57% knees and 48% knees, respectively). Moderate and severe cartilage lesions were common, in 19% and 31% knees, respectively, while moderate and severe bone marrow oedema in 19% and 31% knees, respectively. Moderate-intensity lesion in tendons was found in 21% knees and high-grade tendonitis in 6% knees-the patellar (11% and 2%, respectively) and quadriceps (7% and 2%, respectively) tendons being most affected. Three percent partial ligamentous ruptures were found, especially of the anterior cruciate ligament (2%).

CONCLUSION

Nearly all knees of asymptomatic adults showed abnormalities in at least one knee structure on MRI. Meniscal tears, cartilage and bone marrow lesions of the patellofemoral joint were the most common pathological findings. Bucket handle and complex meniscal tears were reported for the first time in asymptomatic knees.

Chiropractic management of a medial meniscus tear in a patient with tibiofemoral degeneration: a case report

OBJECTIVE

The purpose of this case report is to describe and discuss the clinical diagnosis of a medial meniscus tear in an older patient using a multimodal management approach provided by a chiropractor.

CLINICAL FEATURES

A 60-year-old woman reported to a chiropractic clinic with left knee pain and swelling. The history and physical examination findings suggested a medial meniscus tear, which was confirmed with magnetic resonance imaging.

INTERVENTION AND OUTCOME

Treatment consisted of therapeutic ultrasound; rest, ice, compression, and elevation protocol; soft tissue therapy using effleurage and lymphatic drainage; chiropractic mechanically assisted adjusting techniques to the left knee using a handheld mechanical thrusting instrument; sports taping applied to assist facilitation of the vastus medialis obliquus; and a specific rehabilitation program aimed at strengthening this musculature. The patient's pain was assessed using a quadruple numeric pain scale. Function of the left knee was examined using McMurray, Apley, and a variation of Helfet orthopedic tests, as well as joint line tenderness. Monitoring was done at the initial consultation and at the sixth and 12th treatments. The patient reported being able to walk, swim, and ride a bicycle asymptomatically. Her pain score at the concluding visit was 16.7%, indicating low-intensity pain.

CONCLUSION

This case indicated that conservative management of a meniscus tear through a chiropractic multimodal treatment approach provided an alternative or adjunctive therapy to routine orthopedic surgery for this patient.

Comparative study of imaging at 3.0 T versus 1.5 T of the knee

PURPOSE

The objectives of the study were to compare MR imaging at 1.5 and 3.0 T in the same patients concerning image quality and visualization of cartilage pathology and to assess diagnostic performance using arthroscopy as a standard of reference.

MATERIALS AND METHODS

Twenty-six patients were identified retrospectively as having comparative 1.5 and 3.0 T MR studies of the knee within an average of 102 days. Standard protocols included T1-weighted and fat-saturated intermediate-weighted fast spin-echo sequences in three planes; sequence parameters had been adjusted to account for differences in relaxation at 3.0 T. Arthroscopy was performed in 19 patients. Four radiologists reviewed each study independently, scored image quality, and analyzed pathological findings. Sensitivities, specificities, and accuracies in diagnosing cartilage lesions were calculated in the 19 patients with arthroscopy, and differences between 1.5 and 3.0 T exams were compared using paired Student's t tests with a significance threshold of p < 0.05.

RESULTS

Each radiologist scored the 3.0 T studies higher than those obtained at 1.5 T in visualizing anatomical structures and abnormalities (p < 0.05). Using arthroscopy as a standard of reference, diagnosis of cartilage abnormalities was improved at 3.0 T with higher sensitivity (75.7% versus 70.6%), accuracy (88.2% versus 86.4%), and correct grading of cartilage lesions (51.3% versus 42.9%). Diagnostic confidence scores were higher at 3.0 than 1.5 T (p < 0.05) and signal-to-noise ratio at 3.0 T was approximately twofold higher than at 1.5 T.

CONCLUSION

MRI at 3.0 T improved visualization of anatomical structures and improved diagnostic confidence compared to 1.5 T. This resulted in significantly better sensitivity and grading of cartilage lesions at the knee.

Assessment and management of posttraumatic haemarthrosis of the knee

Traumatic haemarthrosis of the knee poses significant diagnostic difficulty in the acute phase. Orthopaedic follow up is essential. An update of current recommended practice is provided, and the pros and cons of arthroscopy and magnetic resonance imaging are discussed.