MAGNETIC RESONANCE IMAGING OF THE INTERNALLY DERANGED KNEE JOINT - A PROSPECTIVE STUDY

Abstract

BACKGROUND & OBJECTIVE: Trauma to knee joint is a significant cause of morbidity in the young, active individuals and athletes. An accurate diagnosis regarding the type and extent of injuries is essential for early operative as well as non-operative treatment. The most widely used diagnostic modalities to assess the joint in jury are arthroscopy and MRI. Arthroscopy, though accurate, is invasive and can cause complications. Magnetic resonance imaging (MRI) has now been accepted as the best imaging modality for non-invasive evaluation of knee injuries. This study was undertaken to study the types and incidence of injuries in traumatic knee joint by MR imaging and to compare with arthroscopy findings in selected cases. METHODS: DESIGN: Prospective study Setting: In a tertiary care hospital, symptomatic patients who were referred from various service referral hospitals and units with history of trauma and clinical suspicion of IDK were referred to department of Orthopedics, Navodaya Medical College, Raichur. Patients: 50 consecutive patients with suspicion of IDK following knee trauma were selected for the study from 2011 to 2013. INVESTIGATIONS: Clinical examinations, MRI knee (within 4 days of referral) & in selected cases arthroscopy were performed and the findings were compared. Main Outcome Measures: Study of spectrum of MRI findings in traumatic knee and correlation of MRI findings with arthroscopy/surgical findings in selected cases. RESULTS: Of the total 50 patients evaluated, most common injury was ACL tear of which complete tears were more common. PCL tears were less common. Among the Meniscal injuries, MM tears are more common than LM and grade 2 tears are more common in both. MCL tears outnumbered LCL tears and grade 1 and 2 tears are more common in MCL. Osseous/Osteochondral lesions were seen in 17 patients (34%). Most of these were bony contusions involving the femoral and tibial condyles. INTERPRETATION AND CONCLUSIONS: From these observations, we found that MRI Magnetic resonance imaging is an excellent, non invasive, radiation free imaging modality with multiplanar capabilities and excellent soft tissue delineation. It can accurately detect, localize and characterize various internal derangements of the knee joint and help in arriving at a correct anatomical diagnosis thereby guiding further management of the patient.