Acute ankle injuries: association between sprain severity and ancillary findings

ABSTRACT Objective To correlate the significance of osseous, chondral, tendon, and ligamentous injuries with anatomical variations in low-grade versus high-grade acute ankle sprains. Methods We retrospectively identified the magnetic resonance imaging findings of acute ankle sprains (<15 days). Participants with a history of previous sprains, arthritis, tumors, infections, or inflammatory conditions were excluded. Images were independently evaluated by two musculoskeletal radiologists and assessed for osseous, chondral, tendon, and ligamentous injuries and anatomical variations. Participants were divided into low-grade versus high-grade sprain groups, according to the presence of a complete tear in at least one component of the lateral ligament complex. Results The final study group comprised 100 magnetic resonance images (mean age, 36 years), the majority of males (54%), the right ankle (52%), and a mean sprain duration of 5 days. Participants with high-grade sprains presented with increased rates of medial malleolus edema (p<0.001), moderate and large articular effusions (p=0.041), and shorter calcaneonavicular distance (p=0.008). Complete tears of the anterior talofibular ligament and calcaneofibular ligaments were observed in 100% and 51.2% of the participants in the High-Grade Group, respectively. The deltoid ligament complex was partially torn in this group (55.8% versus 8.8%, p<0.001). Extensor tendon retinaculum lesions occurred significantly more frequently in this group (41.9%) compared to the overall study population (23%) (p<0.001). Conclusion Participants with high-grade ankle sprains presented with shorter calcaneonavicular distances and increased rates of medial malleolus edema, deltoid complex partial tears, extensor retinaculum lesions, and articular effusion.

Evaluation of Posterior Element Injury in Traumatic Thoraco-Lumbar Burst Fractures

PURPOSE: The purpose of this study is to examine the frequency of posterior element injury in patients with traumatic thoraco-lumbar burst fractures and to evaluate the correlation between the MR imaging and CT findings. MATERIALS AND METHODS: The MR images of 38 patients with 39 thoraco-lumbar burst fractures and the results of the CT examinations of 28 patients with 29 fractures were retrospectively analyzed. Both procedures were performed within two weeks of injury. Twenty-one males and 17 females were included ; their average age was 51.3 (range, 11-75) years. MR images were evaluated for injury to the posterior ligamentous complex, comprising the supraspinous ligament(SSL), the interspinous ligament(ISL), the flaval ligament(FL), and the capsule of facets. Analysis of the CT findings focused on the posterior bony elements of the lamina, pedicle, spinous process, and facet joint. RESULTS: MR imaging revealed posterior ligamentous injuries in 18(46.2%) of 39 burst fractures ; there was tearing of the ISL in 15 cases(38.5%), of the SSL in 11(28.2%), of the capsule of facets in 11(28.2%), and of the FL in nine(23.1%). Among the 29 burst fracture cases examined by CT, posterior bony injuries were detected in 13(44.8%). Lamina and facet joint fractures were detected in six cases(20.7%), facet separation or dislocation in six(20.7%), and spinous process and pedicle fracture in one(3.4%). In 29 burst fracture cases, both MRI and CT were performed. Among the 18 cases in which MR imaging revealed posterior ligamentous injuries, CT failed to demonstrate posterior element fractures in seven. On the other hand, among the 13 cases in which CT indicated posterior bony fractures, MR failed to reveal posterior ligamentous injuries in two. CONCLUSION: Posterior element injury is frequently found in patients with traumatic thoraco-lumbar burst fractures demonstrated by MR imaging(46.2%) and CT(44.8%). Both MRI and CT are useful tools for the evaluation of posterior element injury, which determines the degree of instability of traumatic burst fracture.

MR Imaging of the Combined Anterior and Posterior Cruciate Ligament Tears: Focussing on the Patterns of Injuries and Associated Findings

PURPOSE: To evaluate the patterns of injuries and frequency of associated findings on MR imaging in patients with both anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears; to compare the associated findings, as seen on MR imaging, in cases with both ACL and PCL tears with those with ACL or PCL tears. MATERIALS AND METHODS: Ten patients with combined ACL and PCL tears, 16 with ACL tears and 18 with PCL tears, all confirmed by arthroscopy or open surgery, were involved in this study. To identify the associated knee injuries, MR images were retrospectively evaluated. RESULTS: In ten patients with combined ACL and PCL tears, open surgery led to the identification of six complete ACL tears (60%), four partial ACL tears (40%), eight complete PCL tears (80%) and two partial PCL tears (20%). Injuries associated with these combined tears, and revealed by MR imaging, comprised six medial collateral ligament injuries (60%), six lateral collateral ligament injuries (60%), five medial meniscal injuries (50%), three lateral meniscal injuries (30%), nine bony injuries (90%), two posterior capsular injuries (20%), and three popliteus muscle injuries (30%). The frequency of popliteus muscle injury was significantly different (p<0.05, Fisher's exact test) between the group with both ACL and PCL tears and that with ACL or PCL tears. CONCLUSION: Associated findings in patients with combined ACL and PCL tears are more frequentthan in those with ACL or PCL tears. In cases involving combined ACL and PCL tears, associated findings-as seen on MR images-should thus be carefully examined.

Injury of Anterior Cruciate Ligament with Associated Bony Lesions: MR Image

PURPOSE: To evaluate the characteristic MR findings in injury of the anterior cruciate ligament (ACL) with associated bony lesions. MATERIALS AND METHODS: We reviewed MR findings and the corresponding arthroscopic or operative results of 48 patients with ACL injuries, and evaluated ACL signal intensity and contour. In associated bony lesions, we determined the location of avulsion fracture and bony bruise. RESULTS: Cmplete ACL tears were seen in 27 cases, partial tears in 13, and avulsion injury in eight. Complete tears showed heterogeneously increased signal intensity with contour bulging in ten cases (37 %), and combined bony lesion in 14 (52 %). ACL with a thin continous low signal intensity band surrounding heterogeneously-increased signal intensity suggested partial tears, and was seen in three of 13 proven cases (23 %) of partial ACL tears ; combined bony lesion was seen in four such cases (31 %). There were eight cases of avulsion fracture ; the most frequent site was the anterolateral portion of the tibial spine (n=6). The most frequent sites of bony lesion were at the midportion of the lateral femoral condyle (n=6), and the posterior portion of the lateral tibial plateau (n=6) ; the next most frequent site was the anterior portion of the lateral tibial plateau (n=5). CONCLUSION: Tearing of the ACL was seen on MRI as ligament discontinuity, and heterogeneously increased signal intensity with ACL contour bulging. The most frequent sites of associated bony lesions were the midportion of the lateral femoral condyle, and the posterior portion of the lateral tibial plateau. In associated bony lesions, bony contusion suggested ACL tearing, but avulsion fracture suggested ligament avulsion injury without tear.

MR Imaging Diagnosis of Posterior Cruciate Ligament Injury: Importance of Ancillary Findings

PURPOSE: To evaluate the importance of two ancillary findings of anterior tibial plateau bruise/fracture and popliteus muscle strain on MR diagnosis of posterior cruicate ligament injury. MATERIALS AND METHODS: We retrospectively evaluated 48 patients with confirmed posterior cruciate ligament tear. We studied the incidence of anterior tibial plateau injury and popliteus muscle strain, and the specificity of popliteus muscle strain with or without bony injury. RESULTS: A complete tear of the posterior cruciate ligament was noted in 37 cases, a partial tear in 11. Anterior tibial plateau lesion was found in 21 of 48 cases (44%); This total was made up of 17/37 PCL complete tears (46%) and 4/11 partial tears (36%). The difference in the incidence of complete and partial tears is not statisticially significant. Popliteus muscle injury was found in 20 of 48 cases (42%), the total consisted of 19/37 PCL complete tears (51%) and 1/11 partial tears (10%). The incidence of 42% is relatively high, approximating that of bony injury. The difference in the incidence of complete and partial tears is statistically significant (p<0.006). Specificity for posterior cruciate ligament tear is 69% (20/29), and when concomitant with anterior tibial plateua injury is 94% (16/17). CONCLUSION: As in the case of anterior cruciate ligament injury, these documented ancillary findings of anterior tibial plateau and popliteus muscle injuries are very helpful when MR diagnosis of posterior cruciate ligament injury itself and differentiation of partial and complete rupture are doubtful.

Acute knee ligaments injuries.

One hundred and ten cases of the acute ligamentous injury of the knee were treated at Siriraj Hospital between 1978 and 1981. The most common cause of the injury was through traffic accidents, then sports injuries. In forty five cases, the injuries were so severe that operative treatments were performed within two weeks of the initial injury, using the combined criteria of Reynolds, O’Conner and Larson. The most frequent operative findings were the combined injury of the anterior cruciate ligament, the medical collateral ligament and the medial meniscus. Primary repair was performed in every case. Some needed reconstructive procedures as well. Four cases developed postoperative infection; three superficial and one deep wound infection. After the wound desloughing and intravenous antibiotics administration, every case did clear up. Follow up of one to three year period showed satisfactory results in most cases, except in complicated cases which had fair results. We concluded that in managing the acute ligamentous injury of the knee, the single most important facet of the problem is the diagnosis. If there is any indication for surgery, it should be performed as early as possible.