The ankle ligaments: consideration of syndesmotic injury and implications for rehabilitation

Syndesmotic ankle sprains in athletes

Ankle sprains are among the most common athletic injuries and represent a significant source of persistent pain and disability. Despite the high incidence of ankle sprains in athletes, syndesmosis injuries have historically been underdiagnosed, and assessment in terms of severity and optimal treatment has not been determined. More recently, a heightened awareness in sports medicine has resulted in more frequent diagnoses of syndesmosis injuries. However, there is a low level of evidence and a paucity of literature on this topic compared with lateral ankle sprains. As a result, no clear guidelines are available to help the clinician assess the severity of injury, choose an imaging modality to visualize the injury, make a decision in terms of operative versus nonoperative treatment, or decide when the athlete may return to play. Increased knowledge and understanding of these injuries by clinicians and researchers are essential to improve the prevention, diagnosis, and treatment of this significant condition. This review will discuss the anatomy, mechanism of injury, diagnosis, and treatment of syndesmosis sprains of the ankle while identifying controversies in management and topics for future research.

Chronic tibiofibular syndesmosis injury of ankle: evaluation with contrast-enhanced fat-suppressed 3D fast spoiled gradient-recalled acquisition in the steady state MR imaging

PURPOSE

To retrospectively determine the accuracy of coronal contrast material-enhanced fat-suppressed three-dimensional (3D) fast spoiled gradient-recalled acquisition in the steady state (SPGR) magnetic resonance (MR) imaging, as compared with that of routine transverse MR imaging, in the assessment of distal tibiofibular syndesmosis injury, with arthroscopy as the reference standard.

MATERIALS AND METHODS

The review board of the College of Medicine in Yonsei University approved this study; informed consent was waived. The study group comprised 45 patients (26 men, 19 women; mean age, 32.1 years; range, 18-58 years) with a chronic ankle injury who had undergone MR imaging and arthroscopic surgery. Three independent readers retrospectively reviewed the two sets of MR images (one set of gadolinium-enhanced 3D fast SPGR images and one set of routine T1-, T2-, and intermediate-weighted images). Scores from 1 to 5 in increasing order of the probability of injury were assigned to both sets. Arthroscopy was the reference standard. Syndesmotic recess height was measured on contrast-enhanced images. The two sets of images were compared for diagnostic performance with receiver operating characteristic (ROC) analysis. Dissection and histologic examination of six cadaveric ankles was performed to assess the syndesmotic area and ascertain the enhancing structure at MR imaging.

RESULTS

At arthroscopy, syndesmotic injury was found in 24 ankles but not in 21 ankles. Areas under the ROC curve were significantly higher for the contrast-enhanced images (P<.05). The contrast-enhanced set showed higher accuracy, sensitivity, and specificity compared with the routine set for the assessment of syndesmosis injury. Mean syndesmotic recess height was significantly greater (P<.05) in patients with syndesmotic injury. Dissection and histologic examination revealed a highly vascular synovial fold in the syndesmotic area that is expected to enhance at MR imaging.

CONCLUSION

In the assessment of chronic syndesmosis injury, coronal gadolinium-enhanced fat-suppressed 3D fast SPGR MR images were more sensitive, specific, and accurate than routine MR images.

Syndesmosis sprains of the ankle: a systematic review

Syndesmosis sprains have received increasing recognition during recent years because of a heightened awareness of the mechanism, symptoms, and signs of injury. Syndesmosis injuries take longer to recover than lateral ankle sprains, and no consensus exists regarding optimal treatment of these injuries. Therefore, we undertook a systematic review of the literature to evaluate the effect of treatment on outcome following syndesmosis injury. We identified six articles that evaluated treatment of syndesmosis injuries. All studies were case series including prospectively collected data of young, active patients with a minimum of 6 months followup and represented the highest level of evidence available. Three specifically addressed patient outcomes at final followup: one indicated 44 percent of patients had acceptable outcomes, and two rated patient outcomes as good to excellent. Time lost from sport ranged from 0 to 137 days, with averages ranging from approximately 10 to 14 days up to 52 days. The studies did not employ consistent diagnosis or grading schemes, did not use uniform treatment protocols, and did not compare treatments. Therefore, this review generates several prospective areas for additional investigation rather than providing strong evidence to support a particular method of treatment.

Evidence-based approach to treatment of acute traumatic syndesmosis (high ankle) sprains

Ankle sprains in the athlete are one of the most common injuries, and syndesmosis or "high-ankle" sprains seem to being diagnosed at an increasing rate. As a result, there has been a heightened interest in recognizing and treating these difficult injuries on a timely basis, particularly in the athlete. Although the recognition and diagnosis of these injuries have improved, there still exists a paucity of information on optimal conservative and operative management. In this paper, a systematic review of the literature was conducted to provide an evidence-based rationale in the diagnosis and treatment of syndesmosis (high ankle) sprains in athletes. It is obvious from the low level of evidence available in the literature on this topic that a great deal of work is needed before conclusive statements regarding the management of these injuries can be made with confidence. The current diagnostic tests are not very specific. Because this is a spectrum of injury, there is a lot of variability in the time lost from sport. It is clear that we need a much more definitive diagnostic process for this injury that allows us to predict the severity of the injury, time loss from sport, and the treatment required.

Ankle syndesmosis injuries: anatomy, biomechanics, mechanism of injury, and clinical guidelines for diagnosis and intervention

Syndesmosis injuries are rare, but very debilitating and frequently misdiagnosed. The purpose of this clinical commentary is to review the mechanisms of syndesmotic injuries, clinical examination methods, diagnosis, and management of the injuries. Cadaveric studies of the syndesmosis and deltoid ligaments are also reviewed for further understanding of stress transmission and the roles of different structures in stabilizing the distal syndesmosis. External rotation and excessive dorsiflexion of the foot on the leg have been reported as the most common mechanisms of injury. The injury is most often incurred by individuals who participate in skiing, football, soccer, and other sport activities played on turf. The external rotation and squeeze tests are reliable tests to detect this injury. The ability of imaging studies to assist in an accurate diagnosis may depend on the severity of the injury. The results of cadaveric studies indicate the importance of the deltoid ligament in maintaining stability of the distal tibiofibular syndesmosis and the congruency of the ankle mortise. Intervention programs with early rigid immobilization and pain relief strategies, followed by strengthening and balance training are recommended. Heel lift and posterior splint intervention can be used to avoid separation of the distal syndesmosis induced by excessive dorsiflexion of the ankle joint. Application of a rigid external device should be used with caution to prevent medial-lateral compression of the leg superior to the ankle mortise, thereby inducing separation of the distal syndesmosis articulation. Surgical intervention is an option when a complete tear of the syndesmotic ligaments is present or when fractures are observed.

Ankle syndesmosis sprains in national hockey league players

BACKGROUND

Although syndesmosis sprains are less common in sports than lateral ankle sprains, they represent a significant source of morbidity. Several studies have described the increased recovery time for these injuries in a variety of sports. No previous study has described this injury in hockey players.

HYPOTHESIS

Syndesmosis ankle sprains require a longer recovery time and are less common than lateral ankle sprains in elite hockey players.

STUDY DESIGN

Uncontrolled retrospective review.

METHODS

The medical records of the St Louis Blues (1994-2001) and Dallas Stars (1991-2001) National Hockey League teams were reviewed by the head athletic trainers. Ankle sprains were identified and divided into 2 groups: syndesmosis and lateral sprains. Player demographics, treatment, and time lost to play were recorded for each injury.

RESULTS

Fourteen players were diagnosed with syndesmosis sprains, and 5 players sustained lateral sprains during this time period. Mean time to return to play in games was 45 days (range, 6-137 days) for syndesmosis sprains versus 1.4 days (range, 0-6 days) for lateral sprains.

CONCLUSIONS

Syndesmosis sprains represent a significant injury in hockey players with an extended time lost and, unlike in other sports, are a more common injury than lateral ankle sprains.

MRI findings associated with distal tibiofibular syndesmosis injury

OBJECTIVE

Our objective was to describe the MRI findings associated with acute and chronic distal tibiofibular syndesmosis injury.

MATERIALS AND METHODS

Ninety-four 1.5-T MRIs of ankles of 90 individuals with histories of severe sprain were assessed by two musculoskeletal radiologists for syndesmosis injury (acute, edema of the syndesmosis; chronic, disruption or thickening of the syndesmosis without edema). We examined associated MRI findings, including anterior talofibular ligament injury (scar, chronic injury; edema, acute injury), bone bruise, osteochondral lesion, tibiofibular joint congruity, tibiofibular recess height, and osteoarthritis. The Fisher's exact test and analysis of variance test were used to evaluate the significance of the associations.

RESULTS

In 94 ankles, syndesmosis injury was seen in 63% (n = 59; 23 acute; 36 chronic). Anterior talofibular ligament injury (acute or chronic) was seen on MRIs in 74% (n = 70; 49 with syndesmosis injury; 21 without; p = 0.03). Bone bruises were present in 24% (n = 23; 18/23 acute; 4/36 chronic; 4/35 no injury; p < 0.0001). Of these, talar dome osteochondral lesions were present in 28% (n = 26; 11/23 acute; 14/36 chronic; 1/35 no injury; p = 0.0001; 13 medial; 13 lateral). The tibiofibular joint was incongruent in 33% (n = 31; 6/23 acute; 21/36 chronic; 4/35 no injury; p < 0.0001). The tibiofibular recess (mean +/- SD) was 1.2 +/- 0.92 cm in acute cases, 1.4 +/- 0.57 cm in chronic cases, and 0.54 +/- 0.68 cm in cases with no syndesmosis injury (p < 0.0001). Osteoarthritis was present in 10% (n = 9; 1/23 acute; 7/36 chronic; 1/35 no injury; p = 0.06).

CONCLUSION

Injury to the distal tibiofibular syndesmosis has a significant association with a number of secondary findings on MRI, including anterior talofibular ligament injury, bone bruises, osteochondral lesions, tibiofibular joint congruity, and height of the tibiofibular recess.

Ilizarov ring fixator for a difficult case of ankle syndesmosis disruption

Syndesmotic stabilization is recommended for tibiofibular diastasis, a Maisonneuve fracture, or syndesmotic instability after fixation of distal tibia-fibula fractures. In the case presented, a syndesmotic stabilization was performed with a screw inserted 2 cm above the tibiotalar joint Subsequent failure occurred due to the weight of the patient and a lack of compliance with the necessary nonweight bearing protocol. The Ilizarov frame was used to reduce and maintain a stable syndesmosis with a simple two-ring construct which allowed the patient to bear weight on the injured limb while his syndesmosis healed. This is not recommend as a routine method of treatment, but is presented as an extended indication of the Ilizarov frame for difficult cases.

Tibiofibular diastasis without ankle fracture: a review and report of two cases

Diastasis of the distal tibiofibular syndesmosis is commonly seen with ankle fractures, but is a rare finding in the absence of fracture. The anatomy, biomechanics, mechanism of injury, evaluation, and radiographic assessment of the tibiofibular syndesmosis are reviewed. The authors present a review and two cases of traumatic ankle diastasis without ankle fracture.

Persistent disability associated with ankle sprains: a prospective examination of an athletic population

The purpose of this study was to examine a young athletic population to update the data regarding epidemiology and disability associated with ankle injuries. At the United States Military Academy, all cadets presenting with ankle injuries during a 2-month period were included in this prospective observational study. The initial evaluation included an extensive questionnaire, physical examination, and radiographs. Ankle sprain treatment included a supervised rehabilitation program. Subjects were reevaluated at 6 weeks and 6 months with subjective assessment, physical examination, and functional testing. The mean age for all subjects was 20 years (range, 17-24 years). There were 104 ankle injuries accounting for 23% of all injuries seen. There were 96 sprains, 7 fractures, and 1 contusion. Of the 96 sprains, 4 were predominately medial injuries, 76 were lateral, and 16 were syndesmosis sprains. Ninety-five percent had returned to sports activities by 6 weeks; however, 55% of these subjects reported loss of function or presence of intermittent pain, and 23% had a decrement of >20% in the lateral hop test when compared with the uninjured side. At 6 months, all subjects had returned to full activity; however, 40% reported residual symptoms and 2.5% had a decrement of >20% on the lateral hop test. Neither previous injury nor ligament laxity was predictive of chronic symptomatology. Furthermore, chronic dysfunction could not be predicted by the grade of sprain (grade I vs. II). The factor most predictive of residual symptoms was a syndesmosis sprain, regardless of grade. Syndesmosis sprains were most prevalent in collision sports. This study demonstrates that even though our knowledge and understanding of ankle sprains and rehabilitation of these injuries have progressed in the last 20 years, chronic ankle dysfunction continues to be a prevalent problem. The early return to sports occurs after almost every ankle sprain; however, dysfunction persists in 40% of patients for as long as 6 months after injury. Syndesmosis sprains are more common than previously thought, and this confirms that syndesmosis sprains are associated with prolonged disability.

Clinical tests for ankle syndesmosis injury: reliability and prediction of return to function

Despite the severity of ankle syndesmosis injuries, it has been argued that they are relatively poorly detected. This study investigated the interrater reliability of four orthopaedic tests for ankle syndesmosis injury and assessed their ability to predict the extended recovery times that have been reported as a consequence of this injury. Nine physiotherapists, working in random pairings, examined 53 subjects, all receiving treatment for ankle injury at two private clinics. Each subject was tested by two physiotherapists who independently performed the palpation test, external rotation test, squeeze test, and dorsiflexion-compression test. Kappa coefficient testing indicated that the external rotation test had the best interrater reliability (kappa = 0.75). The squeeze test was found to have moderate reliability (kappa = 0.50), and the palpation and dorsiflexion-compression tests both had only fair reliability (kappa = 0.36). The degree of pair-wise association between the results of the four tests was low (phi < or = 0.30 for all test combinations), suggesting that if all four tests were performed on the same subject, it was not likely that they would achieve similar results. Follow-up interviews were conducted to determine the time taken for subjects to walk 10 m without pain and, for sports injuries, the time taken to return to training and then to competition. For each test, Mann-Whitney U values showed no significant difference between the recovery times of subjects with positive or negative test results, although subjects with recovery times markedly longer than normal were detected by three of the four tests. When an either/or combination of the external rotation and dorsiflexion-compression tests was considered, subjects with a positive test result took significantly longer to return to playing sports.