Gravity versus manual external rotation stress view in evaluating ankle stability: a prospective study

Deltoid ligament injuries: A review of the anatomy, diagnosis and treatments

PURPOSE

Ankle sprains remain the most common soft tissue injury presenting to Emergency Departments. Recently, there has been increased awareness and reporting of deltoid ligament injuries in association with injuries to the lateral ligament complex as well as with fibula fractures. This article reviews the currently available literature on the anatomy of the deltoid ligament, clinical and radiological diagnosis of injuries to the deltoid ligament and treatment recommendations.

METHODS

A literature review was conducted for keywords associated with deltoid ligament injuries. MEDLINE, PubMed and Embase databases were utilised for this search. Articles were included if involving an adult population, were English-language, were related to deltoid ligament injuries (with or without associated injuries) and reported on patho-anatomy, clinical or radiological diagnosis or treatment methods.

RESULTS

A total of 93 articles were assessed for relevance from the database search, and 47 were included after the removal of irrelevant articles and duplicates. Several studies reported on the clinical findings of deltoid ligament injury, as well as the radiographic analysis. Arthroscopy was considered the gold standard of diagnosis, with authors reporting on the potential benefit of performing arthroscopic repair or reconstruction at the same time. There were no studies that provided a system for the classification of deltoid ligament injury or larger studies of treatment pathways. Long-term studies of the incidence of instability in deltoid ligament injuries were not available.

CONCLUSION

There is limited evidence available regarding deltoid ligament injuries, particularly in terms of treatment options, either in isolation or with concomitant injuries. Long-term follow-up studies are needed to obtain more accurate data on the number of complications.

LEVEL OF EVIDENCE

Level IV.

The additional value of weight-bearing radiographs in assessing stability of isolated type B fibular fractures

INTRODUCTION

In isolated type B fibular fractures, the decision whether to operate or treat conservatively is principally based on congruency and stability of the ankle joint. The purpose of the current study is to examine the additional diagnostic value of the weight-bearing radiograph (WBR) in assessing stability of potentially unstable type B fibular fractures.

MATERIALS AND METHODS

In this retrospective cohort study, patients were selected based on who presented an isolated type B fracture of the fibula. Unstable fractures were directly planned for surgery. Other patients underwent additional weight-bearing imaging 4-7 days after initial trauma, on which definitive treatment was based. The medial clear space (MCS) was compared between the WBR and the conventional radiograph.

RESULTS

A total of 70 patients were included in the period January 2018-December 2021. The average MCS on conventional mortise radiograph was 3.56 mm compared to 3.02 mm on the WBR(p<0.05). The superior clear space (SCS) was equal between both groups (respectively 3.12 mm and 3.08 mm, p = 0.44). All 70 patients were initially treated conservatively with immediate weight-bearing in a brace or soft cast. One patient had the need for open repair and internal fixation due to non-union.

DISCUSSION

Different techniques for the assessment of deep deltoid ligament integrity exist, such as the MRI, the ultrasonography and different kinds of stress test radiographs. As fractured ankles don't need direct fixation and operative treatment can be postponed, a stepped approach for the assessment of deep deltoid ligament (DDL) integrity can be of assistance in assessing ankle stability. In isolated type B fibular fractures a stepped approach, using the weight-bearing radiograph can be of additional value in assessing the stability. It is a low cost, prevents unnecessary surgery and contributes to a quick weight-bearing non-operative treatment.

The Use of the Lateral Tibial Line to Assess Ankle Alignment: A Preliminary Investigation

BACKGROUND

Although the medial clear space (MCS) is commonly used to assess talar alignment and ankle stability, its measurement is variable with multiple reported normal values. We have observed that the lateral tibial shaft is a reliable landmark to assess talar alignment. The objective of the current investigation was to determine the normal relationship of the lateral tibia to the superolateral talus using a tangent drawn inferiorly from the lateral tibial shaft, which we refer to as the "lateral tibial line" (LTL).

METHODS

The relationship of the LTL to the superolateral talus was assessed by three reviewers on 99 standing ankle mortise radiographs in uninjured patients. This relationship was quantified by measuring the distance (in millimeters) between the LTL and the superolateral talus. In addition, the interobserver reliability of the LTL measurement was recorded and compared with that of the MCS.

RESULTS

The median value for the distance between the superolateral talus and LTL was -0.50 mm with an interquartile range of -1.4 to 0.0 mm. The LTL was within 1 mm of the lateral talus in 176 of 297 reviewer measurements (59.3%). Moreover, it was either lateral to or at most 1 mm medial to the lateral talus in 90.9% of cases. The LTL measurement also demonstrated good interobserver reliability (0.764, 95% confidence interval, 0.670 to 0.834), similar to the measurement of MCS (0.742, 95% confidence interval, 0.539 to 0.846).

CONCLUSIONS

The relationship between the LTL and superolateral talus is easily measured with good reliability for assessing the anatomic relationship of the tibia and talus. The LTL uncommonly fell more than 1 mm medial to the superolateral talus, as might be seen with displaced ankle fractures. These findings will hopefully serve as a basis for future studies evaluating its role in assessing lateral displacement and stability of isolated fibula fractures.

LEVEL OF EVIDENCE

Level III, retrospective review.

Successful Outcomes With Nonoperative Treatment and Immediate Weightbearing Despite Stress-Positive Radiographs in Isolated Distal Fibula (OTA/AO 44B) Fractures

OBJECTIVES

To determine whether a nonoperative management protocol results in equivalent outcomes in isolated OTA/AO 44B (Weber B) fractures without initial medial clear space (MCS) widening regardless of stress radiography findings.

METHODS

DESIGN

Prospective cohort.

SETTING

Level 1 academic trauma center.

PATIENT SELECTION CRITERIA

Nonoperatively managed patients with isolated OTA/AO 44B fractures and MCS ≤4 mm on initial non-weightbearing injury radiographs between from January 2018 and January 2022 were included. All patients underwent emergency department gravity stress radiographs and those with widening were considered the widening cohort and those without the non-widening cohort.

OUTCOME MEASURE AND COMPARISONS

MCS measurements on weightbearing radiographs were obtained at first follow-up, 6 weeks, 12 weeks, and 6 months postinjury, were considered indicative of instability if >4 mm and were compared between cohorts.; American Orthopaedic Foot and Ankle Society ankle-hindfoot scores were also compared between cohorts.

RESULTS

Sixty-nine patients were studied. None of the 38 patients (55%) with widening on gravity stress radiographs demonstrated widening with weightbearing radiographs at any time point. Mean MCS measurement differences between the 2 cohorts were statistically significant for all time points ( P = 0.012); however, with a model adjusted mean MCS value of 2.7 mm for the nonwidening cohort and 2.9 mm for the widening cohort, these are not clinically significant. There was no statistically significant difference in overall final American Orthopaedic Foot and Ankle Society scores between the 2 groups ( P = 0.451). In addition, statistical equivalence using Schuirmann 2 one-sided tests was achieved between the 2 groups. Both cohorts had mean American Orthopaedic Foot and Ankle Society scores representing excellent outcomes at the final follow-up.

CONCLUSIONS

Patients with isolated OTA/AO 44B fractures without MCS widening on initial injury radiographs did not demonstrate instability on subsequent weightbearing radiographs and had equivalent outcomes regardless of gravity stress radiography findings when treated nonoperatively. Weightbearing radiographs at the initial follow-up appear to be a reliable assessment of ankle stability in these injuries and are an appropriate alternative to painful and time-consuming stress radiography.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Current concepts in ankle fractures

Ankle fractures are among the most common orthopaedic injuries. Operative management is performed in unstable ankle fracture patterns to restore the stability and native kinematics of the ankle mortise and minimize the risk of post-traumatic degenerative changes. In this study, we review current concepts in ankle fracture management, including posterior malleolus fixation, syndesmosis fixation, deltoid ligament repair, fibular nailing, and early weightbearing, from both a biomechanical and clinical perspective.

The Lateral Drawer Test: A New Clinical Test to Assess Mortise Instability in Weber B Fibula Fractures

Background:

Assessment of mortise stability is paramount in determining appropriate management of ankle fractures. Although instability is readily apparent in bimalleolar or trimalleolar ankle fractures, determination of instability in the isolated Weber B fibula fracture often requires further investigation. Prior authors have demonstrated poor predictive value of physical examination findings such as tenderness, ecchymosis, and swelling with instability. The goal of this study is to test the validity of a new clinical examination maneuver, the lateral drawer test, against the gravity stress view (GSV) in a cohort of patients with Weber B fibula fractures. Secondary goals included assessing pain tolerability of the lateral drawer test, as well as testing interobserver reliability.

Methods:

Sixty-two patients presenting with isolated fibula fractures were prospectively identified by an orthopaedic nurse practitioner or resident. Three nonweightbearing radiographic views of the ankle as well as a GSV were obtained. Radiographs were not visualized before conducting the lateral drawer test. Two foot and ankle fellowship–trained orthopaedic surgeons performed and graded the lateral drawer test. Radiographs were then examined and medial clear space (MCS) was measured. Visual analog scale (VAS) pain scores were obtained before and after testing. The results of the lateral drawer test were compared with radiographic measurements of MCS on GSV. A cadaveric experiment was devised to assess interobserver reliability of the lateral drawer test.

Results:

Thirty (48%) of 62 consecutively enrolled patients demonstrated radiographic instability with widening of the MCS ≥5 mm on GSV. When correlated with MCS measurement, the lateral drawer test demonstrated a sensitivity of 83%, specificity of 97%, positive predictive value (PPV) of 96%, and negative predictive value (NPV) of 86%. There was a strong correlation between the lateral drawer test grade and amount of MCS widening (Spearman correlation ρ = 0.82, P < .005). Patients tolerated the maneuver well with an average increase of 0.7 on the VAS pain scale. Testing of 2 observers utilizing the cadaveric model demonstrated a Cohen’s Kappa coefficient of 0.7 indicating moderate interobserver agreement.

Conclusion:

The lateral drawer test demonstrates high sensitivity, specificity, PPV, and NPV with moderate interobserver reliability compared with the MCS on GSV in patients presenting with Weber B fibula fractures. Although further external validation is required, the lateral drawer test may offer an adjunct tool via physical examination to help determine mortise stability.

Level of Evidence:

Level II, Prospective Cohort Study.

Predisposing Factors for Posttraumatic Osteoarthritis After Malleolus Fracture Fixation in Patients Younger Than 50 Years

BACKGROUND

The purpose of this study was to identify the risk factors for posttraumatic osteoarthritis (OA) after surgery for ankle fractures in patients aged ≤50 years.

METHODS

We performed a retrospective review of consecutive patients who underwent surgery for ankle fractures and were followed up for a minimum period of 5 years. The patients were assigned to 2 groups according to the presence of advanced OA at the last follow-up. Binary logistic regression was used to model the correlation between risk factors and OA. Functional outcomes were assessed using the Foot and Ankle Outcome Score.

RESULTS

The data of 332 patients who met the inclusion criteria were included in the analysis. The overall rate of posttraumatic arthritis was 27.7% (nonarthritis group: 240 patients, arthritis group: 92 patients). The arthritic change was significantly affected by BMI (95% confidence interval [CI] 1.29-19.76; adjusted odds ratio [OR] ≥ 30, 6.56), fracture-dislocation injury (CI 1.66-11.57; adjusted OR, 4.06), posterior malleolus (PM) fracture (CI 1.92-12.73, adjusted OR > 25% of the articular surface, 5.72), and postoperative articular incongruence (CI 1.52-18.10; adjusted OR, 7.21). The mean scores of the arthritis group were lower than those in the nonarthritis group (P < .05).

CONCLUSION

Obesity, fracture-dislocation injury, concomitant large PM fracture, and articular incongruence were risk factors of posttraumatic OA after surgery for ankle fractures. Surgeons should be aware that accurate reduction is critical in patients with ankle fractures with associated large PM fractures, especially those with obesity or severe initial injuries such as fracture-dislocation.

LEVEL OF EVIDENCE

Level III, case control study.

Effectiveness of Gravity and Manual Stress Radiographs and the Use of Lateral Talar Displacement in Determining Ankle Stability of Supination-External Rotation Type Ankle Fractures

OBJECTIVES

(1) To evaluate adequacy and reproducibility of the gravity and manual stress imaging in the diagnosis of unstable ankle fractures and (2) to evaluate the diagnostic utility of lateral talar displacement ratio (LTDR) derived in relation to the talar body width on ankle stress imaging.

DESIGN

Retrospective cohort study.

SETTING

Level 1 Trauma Center.

PATIENTS

One hundred seventy consecutive patients who presented with supination-external rotation 2 ankle fractures (OTA/AO 44-B2.1) requiring dynamic stress testing.

INTERVENTION

Dynamic stress imaging to determine ankle stability.

MAIN OUTCOME MEASURE

Ankle instability and subsequent need for surgical fixation as determined by dynamic stress imaging.

RESULTS

No statistical significant difference was found between the adequacy of gravity stress radiographs and manual stress images in regards to surgical decision-making (P = 0.595). Using manual and gravity stress images, receiver operating characteristic curves were generated for medial clear space (MCS) (area under the curve = 0.793, 0.901) and LTDR (0.849, 0.850), corresponding to thresholds of 10.5% and 10.2% for manual and gravity, respectively. Seventy-three of 105 patients (69.5%) with MCS > 5 mm and 62 of 75 patients (82.7%) with LTDR > 10% were offered surgical intervention. Sixty-two of the 77 patients (80.5%) offered surgery had both MCS > 5 mm and LTDR > 10%.

CONCLUSION

This study shows that manual stress radiographs are just as effective as gravity stress radiographs in making an assessment of ankle fracture stability as there was no difference in diagnostic value between gravity and manual stress imaging in regards to surgical decision-making. Use of additional radiographic measurements such as the LTDR can provide additional information in determining stability when MCS is within a clinical gray area.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Value of Additional Gravity Stress Radiographs for Decision Making in the Treatment of Isolated Type B Distal Fibular Fractures

BACKGROUND

Prior to treatment decisions concerning isolated Weber type B ankle fractures, assessment of the stability of the ankle joint is mandatory. The gravity stress (GS) radiograph is a radiographic tool to determine stability. We hypothesized that this additional GS radiograph would lead to fewer operative treatments by applying the criterion of operative treatment when medial clear space (MCS) > superior clear space (SCS) + 2 mm on the GS radiograph, compared with the nonstressed mortise view criteria of advising operative treatment in case of MCS > SCS + 1 mm.

METHODS

This retrospective comparative cohort study analyzed 343 patients aged between 18 and 70 years with an isolated Weber type B ankle fracture diagnosed at the emergency department between January 2014 and December 2019. The cohort was divided into 2 groups based on whether an additional GS radiograph was performed. Group I consisted of 151 patients in whom a regular mortise and lateral radiograph were performed. Group II comprised 192 patients, with an additional GS radiograph. Primary outcome was type of treatment (conservative vs operative). Secondary outcomes were patient-reported functional outcomes and pain.

RESULTS

Baseline characteristics of both groups did not differ. In group I, surgery was performed in 60 patients (39.7%) compared with 108 patients (56.3%) in group II (P = .002). In the operatively treated patients, the mean MCS on regular mortise view was significantly smaller in patients in whom an additional GS radiograph was performed compared to patients without an additional GS radiograph (4.1 mm vs 5.2 mm, P < .001). Mean Olerud-Molander Ankle Score and mean visual analog scale (VAS) for pain did not differ significantly between groups I and II.

CONCLUSIONS

Contrary to what was hypothesized, the introduction of an additional gravity stress radiograph, by which operative treatment was indicated if the MCS was wider than the SCS + 2 mm, did not result in reduced operative treatment of Weber type B ankle fractures when operative treatment was indicated for MCS > SCS + 1 mm on non-gravity stress radiographs.

LEVEL OF EVIDENCE

Level III: retrospective comparative study.

Fibula fractures management

Isolated distal fibula fractures represent the majority of ankle fractures. These fractures are often the result of a low-energy trauma with external rotation and supination mechanism. Diagnosis is based on clinical signs and radiographic exam. Stress X-rays have a role in detecting associated mortise instability. Management depends on fracture type, displacement and associated ankle instability. For simple, minimally displaced fractures without ankle instability, conservative treatment leads to excellent results. Conservative treatment must also be considered in overaged unhealthy patients, even in unstable fractures. Surgical treatment is indicated when fracture or ankle instability are present, with several techniques described. Outcome is excellent in most cases. Complications regarding wound healing are frequent, especially with plate fixation, whereas other complications are uncommon.

Hybrid Fixation for Danis-Weber Type C Fractures With Syndesmosis Injury

BACKGROUND

This study aimed to assess the clinical and radiological outcomes of hybrid fixation for Danis-Weber type C ankle fractures with a syndesmotic injury.

METHODS

From January 2016 to April 2018, we retrospectively reviewed consecutive patients who underwent hybrid fixation for Danis-Weber type C ankle fractures with syndesmotic injury with a minimum follow-up of 12 months. We excluded patients who achieved syndesmosis stability after fracture fixation. In all patients, we allowed partial weightbearing at 4 weeks postoperatively. We evaluated the visual analog scale for ankle pain, the Olerud-Molander ankle score, and the American Orthopaedic Foot & Ankle Society score. Malreduction of the syndesmosis was defined based on 2 previously reported methods. Fourteen patients (11 men and 3 women) were included in this study. There were 11 patients with pronation external rotation-type fractures and 3 patients with Maisonneuve fractures. The average age at operation was 37.2 years (range, 18-70 years).

RESULTS

Clinical scores were significantly improved at the last follow-up. Postoperative malreduction was observed only in 1 patient (7.1%).

CONCLUSION

Hybrid fixation using a suture-button device combined with a syndesmotic screw in Danis-Weber type C fractures with syndesmosis injury showed a high accuracy of reduction, a low rate of diastasis, and favorable clinical outcomes. This combined method could be a good alternative treatment option for Danis-Weber type C ankle fractures with a syndesmosis injury.

LEVEL OF EVIDENCE

Level IV, case series.

Effect of Muscle Activation on the Gravity Stress View in Unstable Weber B Ankle Fractures

BACKGROUND

In the setting of apparently isolated distal fibula fractures, the gravity stress view (GSV) is a validated method to determine mortise stability. There is currently no published data evaluating whether dynamic muscle activation can reduce an unstable mortise. If patients with instability can overcome gravity, resultant images could yield false-negative results. The goal of this investigation was to determine if patient effort can influence medial clear space (MCS) measurements in proven unstable bimalleolar-equivalent ankle fractures.

METHODS

Patients presenting with Weber B fibula fractures were assessed for mortise stability using the GSV. If the GSV demonstrated instability based on MCS widening >4 mm, 3 additional views were performed: GSV with an assistant maintaining the ankle in a neutral position; GSV with the patient actively dorsiflexing to neutral; and GSV with the patient actively dorsiflexing and supinating the foot. Twenty-four consecutive patients met inclusion criteria, with a mean age of 48.7 (range, 22-85) years. Fifteen patients (62.5%) were female and 9 (37.5%) were male. The laterality was evenly divided.

RESULTS

The mean MCS was 5.8 ± 2.0 6.0 ± 2.6, and 6.2 ± 2.7 mm for the manual assist, active dorsiflexion, and active supination radiograph measurement groups, respectively (P = .434). Only 5 of 24 subjects had any measurable decrease in their MCS with active supination, with a maximum change of 1.2 mm. The remainder of the patients had an increase in MCS ranging from 0.1 to 4.0 mm.

CONCLUSION

There was no significant difference between measurement states indicating that muscle activation is unlikely to yield a false-negative result on GSV. Mortise instability, secondary to deep deltoid injury in the presence of gravity stress, is unlikely to be actively overcome by dynamic stabilizers, supporting the validity and specificity of the GSV.

LEVEL OF EVIDENCE

Level III, prospective study.

The Role of Deltoid Repair and Arthroscopy in Ankle Fractures

Despite the fact that ankle fractures are common injuries, not all patients obtain satisfactory results. Historically, the deltoid ligament injury and intra-articular pathology have not often been treated at the time of fracture stabilization. Recent literature has suggested that repair of the deltoid ligament may lead to better stability of the ankle mortise. Additionally, the use of arthroscopy in conjunction with fracture fixation may allow for better identification and treatment of intra-articular lesions and improve detection and reduction of subtle instability.

Medial tenderness revisited: Is medial ankle tenderness predictive of instability in isolated lateral malleolus fractures?

INTRODUCTION

Determining deltoid ligament incompetence in supination external rotation (SER) injuries commonly relies on stress radiography, given several studies demonstrating low predictive value of physical examination. Stress radiography can be difficult to obtain and may result in suboptimal radiographs with equivocal determination of stability. This study revisits the concept of medial ankle tenderness and its association with mortise instability.

METHODS

Patients who presented with an isolated lateral malleolus fracture underwent prospective data collection. VAS scores were recorded with palpation at the lateral malleolar fracture site, anterior deltoid ligament, and posterior deltoid ligament. Three non-weightbearing radiographs of the ankle and a gravity stress view were obtained. Statistical analysis was performed to determine a correlation between tenderness and instability defined as MCS widening > 4 mm on gravity stress x-ray.

RESULTS

51 patients met inclusion criteria. Group I (stable) and Group II (unstable) demonstrated no difference in tenderness over the lateral malleolus (p = 0.94) or anterior deltoid (p = 0.12), but patients in Group II reported significantly more tenderness over the posterior deltoid (p = 0.03). Taking the higher pain score from either anterior or posterior deltoid palpation, patients with unstable ankle fractures reported significantly more tenderness with medial palpation (p = 0.02). The relative risk of having an unstable ankle fracture with any tenderness to palpation over either the anterior or posterior deltoid ligament was 1.77 (95% CI 1.03 - 3.06, P = 0.039). When comparing no pain versus the presence of any pain with palpation medially, the sensitivity for any medial tenderness to detect an unstable ankle fracture was 0.76 (specificity 0.59, PPV 0.79, NPV 0.56).

CONCLUSION

Patients with any medial tenderness were at significantly higher risk of having an unstable SER ankle fracture in this study, but strict reliance on the presence or absence of medial tenderness without stress radiographs would lead to an unacceptable number of both false positive and false negative determinations of instability. However, our findings suggest that medial tenderness is associated with instability. The 0.79 PPV of any medial tenderness for instability may be useful to cast doubt on equivocal stress radiography and prompt surgeons to repeat stress radiography or shorten the interval for radiographic follow up.

LEVEL OF EVIDENCE

Diagnostic study, Level II-1 (development of diagnostic criteria on basis of consecutive patients [with universally applied reference "gold" standard]).

Ultrasonographic Assessment of Deltoid Ligament Integrity in Ankle Fractures

BACKGROUND

Regardless of fibular status, the presence of a superficial deltoid ligament disruption or a combination of deep and superficial deltoid ligament disruption is central to the decision-making process in treating ankle fractures. The aims of the present study were to test whether ultrasonography can assess deltoid ligament integrity and to determine its validity and reliability by comparing it with gravity stress radiography.

METHODS

A consecutive series of 81 eligible patients with a nondisplaced or minimally displaced fibula fracture identified on a standard radiograph were prospectively enrolled. All patients underwent gravity stress radiography and ultrasonography. Image analysis included the layer type, integrity, and tear site of the deltoid ligament. Ultrasound validity and intra- and interobserver reliability were assessed by the interpretations of the first author and an independent observer who were blinded to the results.

RESULTS

Of all patients, 64 (79.0%) had a deltoid ligament disruption; most of the tears were of both the superficial and deep layers, partial and proximal attachment tears, and only 8 (12.5%) were complete tears. Patients with an intact deltoid ligament had a mean medial clear space (MCS) value of 2.7 ± 0.5 mm, and those with deltoid ligament tears had a mean MCS value of 5.9 ± 3.4 mm (P < .001). In a comparison between ultrasonography and gravity radiography, we found a sensitivity of 100% versus 97%, a specificity of 90% versus 100%, a positive predictive value of 97% versus 100%, and a negative predictive value of 100% versus 90%, respectively. The intra- and interobserver reliability was evaluated as almost perfect in all conditions. In a comparison between ultrasonography and gravity radiography, we found a sensitivity of 100% versus 97%, a specificity of 90% versus 100%, a positive predictive value of 97% versus 100%, and a negative predictive value of 100% versus 90%, respectively.

CONCLUSION

Ultrasonography proved to be an accurate tool, allowing the identification of deltoid ligament disruption and the involved components in a more dynamic fashion. Its relative ease of use and lack of ionizing radiation make it a useful and confident technique that can be performed by an orthopedist.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Ankle Fractures: An Expert Survey of Orthopaedic Trauma Association Members and Evidence-Based Treatment Recommendations

OBJECTIVES

To describe current practice patterns of orthopaedic trauma experts regarding the management of ankle fractures, to review the current literature, and to provide recommendations for care based on a standardized grading system.

DESIGN

Web-based survey.

PARTICIPANTS

Orthopaedic Trauma Association (OTA) members.

METHODS

A 27-item web-based questionnaire was advertised to members of the OTA. Using a cross-sectional survey study design, we evaluated the preferences in diagnosis and treatment of ankle fractures.

RESULTS

One hundred sixty-six of 1967 OTA members (8.4%) completed the survey (16% of active members). There is considerable variability in the preferred method of diagnosis and treatment of ankle fractures among the members surveyed. Most responses are in keeping with best evidence available.

CONCLUSIONS

Current controversy remains in the management of ankle fractures. This is reflected in the treatment preferences of the OTA members who responded to this survey.

LEVEL OF EVIDENCE

Therapeutic Level V. See Instructions for authors for a complete description of levels of evidence.

Ankle gravity stress view in the seated position: A technical tip

The ankle gravity stress view (GSV) is often utilized to elucidate instability in patients with an apparent, isolated lateral malleolus fracture. While this has been demonstrated to have advantages over the manual external rotation stress test, positioning in the lateral decubitus position can be difficult, uncomfortable and time-intensive. We report a simple and safe technique that allows one to obtain a gravity stress view of the ankle with the patient seated.

Management of Isolated Lateral Malleolus Fractures

Isolated lateral malleolus fractures represent one of the most common injuries encountered by orthopaedic surgeons. Nevertheless, appropriate diagnosis and management of these injuries are not clearly understood. Ankle stability is maintained by ligamentous and bony anatomy. The deep deltoid ligament is considered the primary stabilizer of the ankle. In the setting of an isolated lateral malleolus fracture, identifying injury to this ligament and associated ankle instability influences management. The most effective methods for assessing tibiotalar instability include stress and weight-bearing radiographs. Clinical examination findings are important but less reliable. Advanced imaging may not be accurate for guiding management. If the ankle is stable, nonsurgical management produces excellent outcomes. In the case that clinical/radiographic findings are indicative of ankle instability, surgical fixation options include lateral or posterolateral plating or intramedullary fixation. Locking plates and small or minifragment fixation are important adjuncts for the surgeon to consider based on individual patient needs.

Compatibility of Lauge-Hansen Classification Between Plain Radiographs and Magnetic Resonance Imaging in Ankle Fractures

We evaluated the accuracy of the predictive injury sequences of the Lauge-Hansen (L-H) classification using magnetic resonance imaging (MRI) in patients with ankle fractures and determined the possible causes of mismatch. Sixty-five patients with ankle fractures who had a complete series of anteroposterior, lateral, and oblique radiographs and ankle MRI studies available were included. The fracture pattern was assigned by 2 senior orthopedic surgeons according to the L-H classification system. The syndesmotic ligaments, lateral collateral ligaments, and medial deltoid complex ligaments were evaluated on the preoperative MRI scans. Comparisons were performed between the predicted ankle ligamentous injury based on the radiographic L-H classification and preoperative MRI analysis. Of the 65 feet in 65 patients, 50 feet (76.9%) were classified as having a supination-external rotation (SER) fracture, 6 feet (9.2%) as having a pronation-external rotation fracture, 4 feet (6.2%) as having a supination adduction fracture, and 2 feet (3.1%) as having a pronation abduction fracture. The overall compatibility of the radiologic classification with the MRI classification was 66.1%. In the evaluation of 50 feet with the MRI SER designation, maximum compatibility was found for stage 4 (77.3%). The main cause for the discrepancy in the SER designation was missing the presence of deltoid ligament disruption on the plain radiographs, especially in the stage 2 and 3 SER fracture pattern. In the evaluation of deltoid complex injuries, all injuries were localized to the anterior part of the medial deltoid complex. The validity of the L-H classification system was low. A new classification system is needed to address the medial malleolus fracture or deltoid complex injuries without posterior injury. Also, stress radiographs could be added to standard radiographs for the classification to address deltoid complex injuries.

Evaluation and Significance of Mortise Instability in Supination External Rotation Fibula Fractures: A Review Article

Evaluation and management of ankle fractures has progressed in parallel to an evolving understanding of ankle stability. While stability of the mortise had historically been attributed to the lateral malleolus, Lauge-Hansen's contributions followed by multiple other investigations increased the emphasis on the significance of medial-sided injury in destabilizing the mortise. As the importance of the deltoid ligament has been elucidated, the means of assessing ligamentous incompetence and the prognostic significance of an unstable mortise continue to be defined.

LEVEL OF EVIDENCE

Level V, expert opinion.

Role for Primary Repair of Deltoid Ligament Complex in Ankle Fractures

Acute deltoid injuries may occur with ankle fractures. They are often left to heal without repair, possibly leading to chronic medial ankle instability. Stress radiographs identify the need for surgical repair of fractures or soft tissue damage. Gravity stress views have benefits over manually stressing the ankle. MRI can explore the extent of medial soft tissue injuries. Arthroscopy can evaluate and potentially treat deltoid injuries. Interposition of the deltoid may preclude adequate fracture reduction. Except with deltoid tear, fractures should be reduced and fixated, then the deltoid assessed. With persistent instability, primary repair may prevent long-term sequelae.

Two-View Gravity Stress Imaging Protocol for Nondisplaced Type II Supination External Rotation Ankle Fractures: Introducing the Gravity Stress Cross-Table Lateral View

Assessing ankle stability in nondisplaced Lauge-Hansen supination external rotation type II injuries requires stress imaging. Gravity stress mortise imaging is routinely used as an alternative to manual stress imaging to assess deltoid integrity with the goal of differentiating type II from type IV injuries in cases without a posterior or medial fracture. A type II injury with a nondisplaced fibula fracture is typically treated with cast immobilization, and a type IV injury is considered unstable and often requires operative repair. The present case series (two patients) highlights a standardized 2-view gravity stress imaging protocol and introduces the gravity stress cross-table lateral view. The gravity stress cross-table lateral view provides a more thorough evaluation of the posterior malleolus owing to the slight external rotation and posteriorly directed stress. External rotation also creates less bony overlap between the tibia and fibula, allowing for better visualization of the fibula fracture. Gravity stress imaging confirmed medial-sided injury in both cases, confirming the presence of supination external rotation type IV or bimalleolar equivalent fractures. Open reduction and internal fixation was performed, and both patients achieved radiographic union. No further treatment was required at 21 and 33 months postoperatively.

Does Foot Position and Location of Measurement Influence Ankle Medial Clear Space?

PURPOSE

There is still controversy regarding normal and abnormal values of the medial clear space (MCS) of the ankle. The aim of this study was to assess how much different degrees of plantar flexion, with and without stress, influenced the MCS.

METHODS

We submitted 30 volunteers to 6 different anteroposterior ankle radiographs in the following positions: neutral, neutral with external rotation stress, physiologic plantar flexion (FPF), physiologic plantar flexion with external rotation stress, maximum plantar flexion (MPF), and maximum plantar flexion with external rotation stress. The MCS oblique (MCSo) and perpendicular (MCSp) were measured in all images by an experienced foot and ankle surgeon.

RESULTS

The data showed that the position of the foot does influence the value of MCSp and MCSo ( P < .05), except for 3 comparisons. MCSo did not change between FPF with stress and MPF with stress. MCSp did not change in 2 situations: between FPF and neutral with stress and between MPF and FPF with stress.

CONCLUSIONS

This study is unique in showing that different ways of positioning the foot and performing stress radiographs results in different MCS values and that these values differ depending on the anatomical site where they are measured.

LEVELS OF EVIDENCE

Diagnostic, Level IV.

Results of the Gravity Stress Examination in the Normal Patient Population

In ankle fractures, the result of a gravity stress radiographic examination is clinically used to determine if a patient may need surgical intervention. The purpose of this study is to report the results of a gravity stress examination in the normal patient population. Fifty study participants were prospectively enrolled and complete ankle radiographs were obtained, including a nonweightbearing gravity stress examination. The mean medial clear space in the gravity stress view was 3.6 mm. This compared to a mean medial clear space of 3.3 mm, and 3.1 mm in the anteroposterior and mortise views. These values were statistically significantly different from the gravity stress view (  P = .006 and P < .001, respectively). There was no statistically significant difference between the talar tilt as measured on the anteroposterior and gravity stress radiographs (  P = .22). No participant had medial clear space widening with gravity stress to more than 5.2 mm or an increase in their widening by more than 0.2 mm. In conclusion, this study helps guide surgeons by providing normative radiographic data for a gravity stress examination and supports the notion that measureable medial clear space widening or talar tilt on gravity stress examination represents an unstable injury.

LEVELS OF EVIDENCE

Level II: Prospective.