Competence of the deltoid ligament in bimalleolar ankle fractures after medial malleolar fixation

BACKGROUND: The stability of the ankle joint is provided by the medial and lateral malleoli and ligaments. Recent studies of cadaveric ankles have demonstrated that injury to the medial structures of the ankle is necessary to allow lateral subluxation of the talus after fracture. However, cadaveric models are limited by the fracture pattern chosen for the model. We sought to investigate the competency of the deltoid ligament in vivo in patients with an operatively treated bimalleolar ankle fracture. METHODS: Twenty-seven patients with a bimalleolar ankle fracture were evaluated. In each patient, the medial malleolus was anatomically reduced and fixed. A radiograph of the ankle was then made with application of an external rotation load to the joint. All lateral malleolar injuries were then reduced and fixed. The radiographs were evaluated for restoration of the competence of the deltoid ligament according to established criteria. RESULTS: Seven (26 percent) of the twenty-seven patients had radiographically evident incompetence of the deltoid ligament after medial malleolar fixation. This finding was associated with a small medial malleolar fragment. CONCLUSIONS: In bimalleolar fractures, the medial injury may be an osseous avulsion, leaving the deltoid intact on the displaced fragment, or it may be a combination of ligamentous and osseous injury with disruption of the deep portion of the deltoid ligament.     

Ultrasonography as a diagnostic tool in assessing deltoid ligament injury in supination external rotation fractures of the ankle

The medial deltoid ligament is the primary stabilizing structure in the ankle joint following lateral malleolar fracture. However, medial deltoid ligament ruptures are difficult to diagnose using current imaging modalities. We hypothesized that ultrasonography can be used to accurately allow early clinical assessment of ankle fracture stability, thereby negating the need to perform plain film stress views of the acutely injured ankle. This prospective study included 12 patients (age range, 18-72) with supination external rotation fractures requiring operative fixation. Following induction of anesthesia, ultrasonography examination was performed, followed by an arthrogram under fluoroscopic screening. Radiographs, ultrasonography, and arthrographic findings were compared. There was 100% correlation between ultrasonography and arthrogram findings. Ultrasonography accurately diagnosed medial deltoid rupture with a sensitivity of 100% and specificity of 100%. Plain film radiographs of the ankle had a sensitivity of 57.1% and a specificity of 60%. The difference between these was significant (χ(2)=.0091). This study demonstrates diagnostic ultrasonography to be an accurate diagnostic modality in assessing medial deltoid ligament integrity in patients with supination external rotation fractures. It offers the same sensitivity and specificity as arthrography without the need for additional invasive procedures. Its relative ease of use and lack of ionizing radiation make it a potentially useful tool, particularly in a busy trauma service.     

Deltoid ligament integrity in lateral malleolar fractures: a comparative analysis of arthroscopic and radiographic assessments

Foot and ankle surgeons often rely on the medial clear space to evaluate competency of the deep deltoid ligament when evaluating ankle fractures. This investigation assesses the integrity of the deep deltoid ligament after lateral malleolar fracture by using direct arthroscopic visualization and medial clear-space separation on plain film radiographs. The objectives of this study were to test the reliability of medial clear-space separation and the Lauge-Hansen classification scheme in predicting deep deltoid rupture in displaced lateral malleolar fractures. The medial clear space was measured on injury radiographs of 40 patients with an isolated displaced lateral malleolar fracture who underwent open reduction and internal fixation. Injury radiographs were classified according to the Lauge-Hansen scheme. Direct arthroscopic visualization was used to evaluate the deep deltoid ligament under manual stress before fracture reduction. The mean preoperative medial clear space in patients with a deep deltoid rupture (n = 13) was 6.6 +/- 2.4 mm (range, 4 to 12 mm), and in patients without a deep deltoid rupture (n = 26), it was 4.0 +/- 1.0 mm (range, 2.5 to 6 mm) (P =.002, 2-sample t test). At an injury medial clear space > or =3 mm, the false positive rate for deltoid rupture was 88.5% (P =.54, Fisher's exact test). At > or =4 mm, the false positive rate was 53.6% (P =.007). All fractures were rotational injuries according to the Lauge-Hansen system. Three fractures were not classifiable; another 3 fractures showed deltoid ligament integrity opposite the expected finding. The results indicate that, in isolated displaced fractures of the lateral malleolus, radiographic widening of the medial clear space is not a reliable indicator for deep deltoid rupture. Some fractures considered stable by the Lauge-Hansen classification may require careful scrutiny to rule out deep deltoid injury.     

Deltoid ligament injuries: diagnosis and management

The medial ligaments of the ankle are injured more often than generally believed. Complete deltoid ligament tears are occasionally seen in association with lateral malleolar fractures or bimalleolar fractures. Chronic deltoid ligament insufficiency can be seen in several conditions, including posterior tibial tendon disorder, trauma- and sports-related deltoid disruptions, and valgus talar tilting in patients who have a history of triple arthrodesis or total ankle arthroplasty. This article focuses on the anatomy and function of the medial ligaments of the ankle and establishes a rationale for the diagnosis and treatment of incompetent deltoid ligament.     

Are outcomes of bimalleolar fractures poorer than those of lateral malleolar fractures with medial ligamentous injury?

BACKGROUND: Recommendations for surgical treatment and expected outcomes differ for two unstable patterns of supination-external rotation ankle injuries. We compared the demographic characteristics and functional outcome following surgical stabilization between the two types of supination-external rotation type-4 fractures: distal fibular fracture with a deltoid ligament rupture and bimalleolar fracture. METHODS: Demographic data on 456 patients in whom an unstable fracture of the ankle was treated surgically were entered into a database and the patients were prospectively followed. Two hundred and sixty-six of these patients sustained either a bimalleolar fracture or a lateral malleolar fracture with insufficiency of the deltoid ligament and widening of the medial clear space. No medial fixation was used in the patients with a deltoid ligament injury. All patients followed a similar postoperative protocol. The patients were followed clinically and radiographically at three, six, and twelve months after the surgery. Function was assessed with the Short Musculoskeletal Function Assessment and the American Orthopaedic Foot and Ankle Society score. RESULTS: Bimalleolar fractures were more commonly seen in female patients, in those older than sixty years of age, and in patients with more comorbidities. There was no significant association between the fracture pattern and either diabetes or the length of the hospital stay. At a minimum of one year postoperatively, the patients with a bimalleolar fracture had significantly worse function, even after we controlled for all other variables. The overall complication rate, including elective hardware removal, was also higher in the group with a bimalleolar fracture (seventeen compared with nine patients). CONCLUSIONS: At one year after surgical stabilization of an unstable ankle fracture, most patients experience little or mild pain and have few restrictions in functional activities. However, the functional outcome for those with a bimalleolar fracture is worse than that for those with a lateral malleolar fracture and disruption of the deltoid ligament, possibly because of the injury pattern and the energy expended.     

Posterior Malleolus Fracture Displacement Is Associated with Rotational Ankle Fracture Stability in Patients Without Medial Malleolar Fractures

Background

The optimal method for the determination of ankle stability remains controversial in rotational ankle fractures without medial bony injury.

Questions/Purposes

The purposes of this study were to (1) evaluate whether posterior malleolar (PM) fracture displacement is associated with deltoid ligament injury in supination-external rotation (SER) ankle fractures and (2) compare the diagnostic accuracy of PM displacement and magnetic resonance imaging (MRI) evaluation of the deep deltoid ligament in identifying fractures with deltoid ligament incompetence.

Methods

Patients with rotational bimalleolar injuries containing lateral malleolar and PM fractures without bony medial injury were included. After operative lateral and PM fixation, an external rotation stress test was performed to evaluate deltoid ligament stability. Operative dictations were reviewed to confirm injury pattern, stability on stress test, and visual inspection of the deltoid ligament. Maximum PM displacement was assessed on lateral X-ray. Pre-operative MRI of the ankle was performed following closed reduction and splinting.

Results

The final cohort consisted of 13 trimalleolar equivalent fractures (torn deltoid ligament) and 20 bimalleolar fractures (medial malleolus and deltoid ligament intact). Average PM displacement was significantly higher for SER trimalleolar equivalent patterns when measured on lateral X-ray. The sensitivity of detecting trimalleolar equivalent fracture was higher on all reported X-ray findings than the sensitivity obtained by the reported MRI findings of deltoid ligament injury.

Conclusion

PM displacement on X-ray is a useful adjuvant along with external rotation stress radiography and MRI evaluation of deep deltoid integrity to distinguish between stable and unstable fracture patterns and thus helps facilitate treatment decisions.

     

MRI与术中外旋应力试验在旋后-外旋踝关节骨折中的应用价值比较

背景：旋后-外旋骨折占所有踝关节骨折的40%~75%。其治疗方式的选择主要依赖对内侧结构损伤程度的判断,特别是内侧三角韧带是否有损伤。循证医学的资料表明,术前MR扫描与术中外旋应力试验是判断三角韧带损伤的方法。那么,术前MR扫描是否可以替代术中应力试验,明确三角韧带损伤的情况并指导踝骨折采用保守治疗或手术治疗。本文试图通过手术验证两者的敏感性是否一致。目的：探讨MRI与术中外旋应力试验在判断踝关节旋后-外旋型损伤程度中的应用价值。方法：2008年1月至2012年12月,我院收治的Lauge-Hansen分型旋后-外旋型踝关节骨折患者,共计30例,术前常规行X线、MR扫描,记录踝关节内侧三角韧带损伤情况。麻醉后行踝关节外旋应力位摄片,依据踝关节内侧间隙是否正常判定三角韧带损伤情况。再比较外旋应力试验与MR结果。结果：MR扫描对三角韧带损伤情况判定,等同于术中外旋应力试验。结论：MRI对于判断三角韧带是否损伤有一定价值,可以指导旋后-外旋型踝关节骨折不同程度损伤的鉴别与治疗方法的选择。     

Stable ankle joint fractures. Indications for operative or conservative treatment?

In German literature, ankle joint fractures are mostly classified in three groups according to Weber. In cases of the type A, the fracture line runs below, in cases of type B at height of the syndesmotic ligaments. C-type fractures are typically seen above this region. However, this practical and simple classification allows no inferences at accompanying injuries which in turn influence the functional outcome. We observed isolated fractures of the lateral malleolus in more than 60% of all type B-fractures, as soon as in the majority the type A-fractures. Since isolated medial ankle fractures occur very rarely, careful exclusion of further injuries is advisable here. In order to differentiate stable ones from unstable type B ankle injuries, we carry out a manual stress test, if there is less than 2 mm fracture dislocation and a congruent ankle mortise. In this manner we could find that stable lateral ankle fractures are characterized with a combination of an intact dorsal syndesmotic and medial ligament. Stable type B and undisplaced type A fractures were treated conservatively with an ankle brace (Aircast?). Unstable ankle injuries were treated by ORIF. Conservative treatment for undisplaced medial malleolar fractures is recommended, if x-rays showed less than 2 mm dislocation which allows a tibio-talare impingement. Biomechanical investigations could prove a significant increase in ankle joint stability, when an axial load of 300 N was applied to various horizontal loads. The talus does not follow automatically a displaced fibular fracture. The dorsal syndesmotic and the medial deltoid ligaments control ankle joint stability.     

The contribution of anterior deltoid ligament to ankle stability in isolated lateral malleolar fractures

The treatment of isolated lateral malleolar fractures with deltoid ligament rupture remains controversial. We prospectively analysed 35 patients with isolated lateral malleolar fractures during 2006–2013. Radiography and magnetic resonance imaging (MRI) were performed to assess the degree of reduction, ligament damage, and stability. Internal fixation was performed for all unstable valgus fractures with unacceptable fracture parameters. Fractures with residual valgus instability after fixation underwent anterior deltoid repair. The mean anterior deltoid ligament grade based on MRI was significantly different between the high-grade unstable group and the stable and low-grade unstable groups (p = 0.037 and 0.004, respectively). Postoperative medial clear space measurements were not significantly different between groups. MRI was shown to be a useful tool in the preoperative identification of isolated lateral malleolus fractures prone to valgus instability. In the case of high-grade unstable fractures of the lateral malleolus, repair of the anterior deltoid ligament is adequate for restoring medial stability.     

Does medial tenderness predict deep deltoid ligament incompetence in supination-external rotation type ankle fractures?

OBJECTIVE: To identify whether medial tenderness is a predictor of deep deltoid ligament incompetence in supination-external rotation ankle fractures. DESIGN: All Weber B lateral malleolar fractures with normal medial clear space over a 9 month period were prospectively included in the study. Fracture patterns not consistent with a supination-external rotation mechanism were excluded. SETTING: High-volume tertiary care referral center and Level I trauma center. PATIENTS/PARTICIPANTS: Fifty-five skeletally mature patients with a Weber B lateral malleolar fracture and normal medial clear space presenting to our institution were included. INTERVENTION: All study patients had ankle anteroposterior, lateral, and mortise radiographs. Each patient was seen and evaluated by an orthopedic specialist and the mechanism of injury was recorded. Each patient was assessed for tenderness to palpation in the region of the deltoid ligament and then had an external rotation stress mortise radiograph. MAIN OUTCOME MEASURE: Correlating medial tenderness with deep deltoid competence as measured by stress radiographs. RESULTS: Thirteen patients (23.6%) were tender medially and had a positive external rotation stress radiograph. Thirteen patients (23.6%) were tender medially and had a negative external rotation stress radiograph. Nineteen patients (34.5%) were nontender medially and had a negative external rotation stress radiograph. Ten patients (18.2%) were nontender medially and had a positive external rotation stress radiograph. We calculated a chi statistic of 2.37 as well as the associated P value of 0.12. Medial tenderness as a measure of deep deltoid ligament incompetence had a sensitivity of 57%, a specificity of 59%, a positive predictive value of 50%, a negative predictive value of 66%, and an accuracy of 42%. CONCLUSION: There was no statistical significance between the presence of medial tenderness and deep deltoid ligament incompetence. There is a 25% chance of the fracture in question with medial tenderness having a positive external rotation stress and a 25% chance the fracture with no medial tenderness having a positive stress test. Medial tenderness in a Weber B lateral ankle fracture with a normal clear space on standard plain radiographs does not ensure the presence of a positive external rotation stress test.     

The use of weightbearing radiographs to assess the stability of supination-external rotation fractures of the ankle

Background  

Isolated lateral malleolar fractures usually result from a supination-external rotation (SER) injury and may include a deltoid ligament rupture. The necessity of operative treatment is based on the recognition of a relevant medial soft-tissue disruption. Currently used tests to assess ankle stability include manual stress radiographs and gravity stress radiographs, but seem to overestimate the need for fracture fixation.     

High incidence of spring ligament laxity in ankle fractures with complete deltoid ruptures and secondary first ray instability

AimsTo assess the incidence of spring ligament failure in patients who have complete deltoid ruptures.Patients and methodsThe authors retrospectively analysed ankle fractures in our trauma database from January 2015 to January 2019. 61 patients who sustained ankle fractures with complete deltoid ligament ruptures based on an AP ankle radiographs with increased medial joint space were identified. 25 patients attended clinic for assessment. Of these, 5 were found to have gross planovalgus with pre-existing spring ligament laxity in the uninjured control foot and these were excluded from the analysis. 20 patients were assessed for spring ligament failure /laxity. For each patient, the uninjured foot was used as the control.ResultsThe TMT instability score and the lateral translation score showed statistically significant increases in the injured compared to the uninjured foot. The ratio of increase in both TMT instability and lateral translation scores (strain) in the injured versus the uninjured foot was assessed. A strong correlation (+0.62 pearson correlation coefficient) was found between the two ratios.ConclusionAll 20 patients showed increased spring ligament laxity and 19 patients showed increased TMT instability. Our results show that with complete deltoid rupture, there is likely greater disruption of the medial ligamentous structures of the foot than previously recognised. The degree of increase in the spring ligament strain also correlates with the degree of strain at the plantar TMT joint ligaments, and thus first ray instability. This finding has significant implications for the long-term assessment and management of ankle fractures involving complete deltoid disruption. Early intervention with orthotics in this cohort may prevent progressive destabilisation of the midfoot and the first ray. This evolving understanding may lead to the prospect of earlier surgical intervention to reconstitute the integrity of the spring ligament and protect the foot progressing to stage 2 AAFD.     

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.     

外踝骨折后三角韧带损伤程度的X线与MRI比较研究

目的 探讨急性外踝骨折后X线片与MRI评价三角韧带损伤程度的影像学诊断价值.方法 总结医院PACS系统中41例急性外踝骨折(排除合并内踝骨折病例)的X线片和MR影像资料,于踝穴位X线片上测量踝内侧间隙(medial clear space,MCS)宽度,应用MR影像对三角韧带深层(胫距后韧带)及浅层(胫弹簧韧带和胫跟韧带)损伤进行评价分级,统计分析MCS与三角韧带损伤程度的相关性;分别记录以X线片和MRI为参考的全部病例Lauge-Hansen分型.结果 MCS与三角韧带损伤等级呈正相关,经ROC曲线分析,判定三角韧带完全断裂(深层和浅层同时)的MCS最适临界值和深层单独完全断裂的MCS最适临界值均为7.85 mm;而判断浅层完全断裂的MCS最适临界值是6.48mm;以MRI为金标准,所有病例Lauge-Hansen分型的准确性为58.5％,但预测三角韧带断裂的准确性达82.9％,只是难以区分深层和(或)浅层断裂.结论 急性外踝骨折后即使未出现内踝骨折,也常伴有三角韧带损伤,X线片仍是踝关节骨折评价的首选检查技术,而MR检查是明确三角韧带损伤程度的敏感辅助检查技术.     

后外侧入路治疗后踝骨折的疗效及并发症

目的：探讨后外侧入路治疗后踝关节骨折的临床疗效及并发症。方法：采用后外侧入路治疗后踝骨折患者34例,采用Lauge-Hansen分型,旋后-外旋型26例;旋前-外旋型损伤8例。CT检查显示27例后踝骨折块占胫骨远端关节面积大于25%,7例大于10%,骨折移位程度均大于2 mm。术后采用Baird-Jackson踝关节功能评定标准对患者踝关节功能进行评价。结果：34例患者均获得随访,平均随访12.5个月。术后2周伤口一期愈合。复查X线检查,骨折对位满意,后踝骨折均获得骨性愈合。4例患者出现腓肠神经支配区麻木,2例患者术后半年完全恢复,1例有所好转,1例无明显改善。3例患者踝部疼痛明显,取出外踝钢板后症状消失。Baird-Jackson踝关节评分优20例,良9例,可4例,差1例,优良率85.3%。结论：后外侧入路治疗后踝骨折便于骨折复位且固定牢靠,可同时处理腓骨骨折。     

Ultrasound findings of the deltoid ligament in patients with acute ankle sprains: A retrospective review

BackgroundThe deltoid ligament is a complex structure composed of multiple ligaments located on the medial side of the ankle joint that can be injured by ankle sprains. Although there have been previous reports on ultrasound imaging of the injured deltoid ligament, a systematic method for depicting each ligament component has not been established. This study aimed to clarify the ultrasound findings of the deltoid ligament in ankle sprains using a systematic scanning protocol.MethodsWe examined the tenderness of the medial ankle and evaluated the ultrasound findings of the deltoid ligament in 169 sprained ankles with no fracture, within 3 days after injury. Observation and evaluation of the six components of the deltoid ligament were performed using a systematic scanning protocol with four probe positions.ResultsOf the 169 ankles, 48 ankles had tenderness in the deltoid ligament. Ultrasonography confirmed deltoid ligament damage in 13 of these 48 ankles. Of the 13 ankles, 3 ankles had damages only in the superficial layer, 3 ankles only in the deep layer, and 7 ankles in both the superficial and deep layers.ConclusionsWe clarified the details of the damage pattern of the deltoid ligament in acute ankle sprains. It was possible to identify the superficial and deep layers of the ligament and to observe the damage pattern of each ligament component in detail, and it appeared that ultrasonography could be used as a tool to evaluate the damage pattern of the deltoid ligament in acute ankle sprains.     

Diagnostic Value of Ultrasound in Ankle Sprain

The present study aimed to evaluate the sensitivity and specificity of clinical tests and ultrasonography in detecting ankle ligament injuries. In this cross-sectional study, 105 patients with a history of ankle sprain were included. Ankle ligaments, including syndesmosis of ankle, as well as deltoid, calcaneofibular, anterior talofibular, and posterior talofibular ligaments were evaluated by clinical tests, ultrasonography, and magnetic resonance imaging. The sensitivity and specificity of ultrasound and clinical tests were assessed in normal, sprain, partial tear, and complete tear groups. The inter-observer reliability (Cohen's Kappa score) of the evaluated techniques with magnetic resonance imaging was assessed. Anterior drawer test showed a sensitivity and specificity of 81 and 80% in the detection of anterior talofibular ligament injuries, respectively. Ultrasonography showed 100% sensitivity and specificity in distinguishing normal anterior talofibular ligament from the torn or sprained ligament with a kappa value of 1. The sensitivity of ultrasonography in detecting normal calcaneofibular ligament and deltoid ligament was 93% and 90%, respectively. Ultrasonography was highly specific in detecting calcaneofibular ligament tear but it was not sensitive in this regard. Ultrasonography was proved reliable in determining the normal anterior talofibular ligament and calcaneofibular ligament from the torn or sprained ligament. Ultrasonography is an effective complementary tool for primary evaluation of ankle injuries, which leads to early diagnosis and efficient quality of care. Clinical tests are not reliable to rule out the ankle ligaments injury and the results should be interpreted with caution.     

The diagnosis and treatment of deltoid ligament lesions in supination–external rotation ankle fractures: a review

The supination-external rotation or Weber B type fracture exists as a stable and an unstable type. The unstable type has a medial malleolus fracture or deltoid ligament lesion in addition to a fibular fracture. The consensus is the unstable type and best treated by open reduction and internal fixation. The diagnostic process for a medial ligament lesion has been well investigated but there is no consensus as to the best method of assessment. The number of deltoid ruptures as a result of an external rotation mechanism is higher than previously believed. The derivation of the injury mechanism could provide information of the likely ligamentous lesion in several fracture patterns. The use of the Lauge-Hansen classification system in the assessment of the initial X-ray images can be helpful in predicting the involvement of the deltoid ligament but the reliability in terms of sensitivity and specificity is unknown. Clinical examination, stress radiography, magnetic resonance imaging, arthroscopy, and ultrasonography have been used to investigate medial collateral integrity in cases of ankle fractures. None of these has shown to possess the combination of being cost-effective, reliable and easy to use; currently gravity stress radiography is favoured and, in cases of doubt, arthroscopy could be of value. There is a disagreement as to the benefit of repair by suture of the deltoid ligament in cases of an acute rupture in combination with a lateral malleolar fracture. There is no evidence found for suturing but exploration is thought to be beneficial in case of interposition of medial structures.     

Extraperiosteal plating of pronation-abduction ankle fractures

BACKGROUND: Pronation-abduction ankle fractures frequently are associated with substantial lateral comminution and have been reported to be associated with the highest rates of nonunion among indirect ankle fractures. The purpose of the present study was to report the technique for and outcomes of extraperiosteal plating in a series of patients with pronation-abduction ankle fractures. METHODS: Thirty-one consecutive patients with an unstable comminuted pronation-abduction ankle fracture were managed with extraperiosteal plating of the fibular fracture. The average age of the patients was forty-four years. There were nineteen bimalleolar and twelve lateral malleolar fractures with an associated deltoid ligament injury. No attempt to reduce the comminuted fragments was made as this area was spanned by the plate. The patients were evaluated functionally (with use of the American Orthopaedic Foot and Ankle Society score), radiographically, and clinically (with range-of-motion testing). RESULTS: Immediate postoperative and final follow-up radiographs showed that all patients had a well-aligned ankle mortise on the fractured side as compared with the normal side on the basis of standardized measurements. All fractures healed without displacement. At a minimum of two years after the injury, the average American Orthopaedic Foot and Ankle Society score (available for twenty-one patients) was 82. The range of motion averaged 13 degrees of dorsiflexion and 31 degrees of plantar flexion, with one patient not achieving dorsiflexion to neutral. There were no deep infections, and one patient had an area of superficial skin breakdown that healed without operative intervention. CONCLUSIONS: Extraperiosteal plating of pronation-abduction ankle fractures is an effective method of stabilization that leads to predictable union of the fibular fracture. The results of this procedure are at least as good as those of other techniques of open reduction and internal fixation of the ankle, although specific results for pronation-abduction injuries have not been previously reported, to our knowledge.     

Does a positive ankle stress test indicate the need for operative treatment after lateral malleolus fracture? A preliminary report

OBJECTIVES: At our institution, a standardized protocol using magnetic resonance imaging (MRI) to evaluate ankle stability and need for surgery following a positive manual stress test for isolated lateral malleolus fractures has been used. The purpose of this study was to evaluate the results using this standardized protocol. DESIGN: Retrospective review. SETTING: University teaching hospital. PATIENTS:: Twenty-one patients who had a positive ankle stress test (>or=5 mm clear space widening) after isolated Weber B lateral malleolus fracture were further evaluated by MRI to determine the status of the deep deltoid ligament. INTERVENTION: If the MRI showed the deltoid ligament was completely disrupted, the patient was advised to have operative ankle repair. However, if the MRI demonstrated that the deep deltoid was intact or only partially disrupted, the patient was treated nonoperatively in a walking boot with weightbearing as tolerated ambulation. MAIN OUTCOME MEASUREMENT: Patients were followed until fracture union and contacted at 12-month minimum follow-up to determine outcomes by radiographic evaluation, health related quality of life (HRQOL) based on Short Form (SF)-36 results and functional outcomes based on the American Orthopaedic Foot and Ankle (AOFAS) and patient report of treatment satisfaction. RESULTS: Twenty-one patients had an MRI after a positive ankle stress test and comprised the study group. There were 12 men and 9 women with an average age of 27 years (range, 16-62 years). Absolute medial clear space measurement on stress testing ranged from 5 to 8 mm. In all, 19 of 21 patients (90%) had evidence of partially torn deep deltoid ligament on MRI and were treated nonoperatively, whereas two patients had MRI findings of a complete deep deltoid injury and underwent surgical treatment. There were no statistically significant correlations between the medial clear space measurements and MRI documentation of complete deltoid ligament rupture. All fractures united without evidence of residual medial clear space widening or posttraumatic joint space narrowing. Of the 15 patients who were available for 1 year minimum follow-up and agreed to come back for clinical and radiographic evaluation, 14 had an AOFAS score of 100, with the remaining patient having a score of 85. HRQOL based on SF-36 results indicated all patients were above or at normal levels, and all patients reported that they were satisfied with their treatment; 93% (14/15) indicated that they would make the same treatment decision again. CONCLUSIONS: Using our protocol, we were able to identify and provide effective nonoperative care to 19 patients who otherwise might have underwent operative treatment after an isolated lateral malleolus fracture. Further work is needed to identify the subset of patients who could be treated nonoperatively without a need for MRI scanning.