Medial Malleolar Fractures and Associated Deltoid Ligament Disruptions: Current Management Controversies

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.

Is just one screw really enough? Single- versus double-screw in the medial malleolus in supination-external rotation ankle fractures: A comparative biomechanical study using partially threaded cancellous screws

OBJECTIVE

The aim of this study is to investigate stiffness and the maximum load to failure values of single- and double-screw fixation of oblique medial malleolus fractures using partially threaded cancellous screws. Our hypothesis is that single-screw fixation of medial malleolus fractures after SER injuries provides similar stiffness when compared with double-screw fixation.

DESIGN

Biomechanical study.

METHODS

Twelve composite polyurethane synthetic right distal tibiae were used in the experiment. Oblique fractures of the medial malleolus were created with a band saw using a custom-made osteotomy guide to standardize the cuts in all models. Bone models were randomly separated into two groups and fixed with one (n = 6) or two (n = 6) 4.0 mm partially threaded cancellous screws placed perpendicular to the fracture line. These were tested by applying an offset axial tension at 10 mm/minute up to maximum load displacement, defined as subsidence of the medial malleolus fragment. Maximum load to failure was determined for the groups at the point where the curve ceased to be linear and suffered an inflection. Force versus displacement curves were obtained and recorded. The student's t-test for independent samples was used to compare stiffness (N / mm) and maximum load (N) between experimental groups, with a p value of < 0.05.

RESULTS

There were no significant differences in stiffness (p = 0.290) and maximum load (p = 0.191) among the two fixation constructs. Mean stiffness was 62.26 (±SD 21.11) N/mm for double-screw fixation group and 48.24 (±SD 22.40) N/mm for single-screw fixation group. Mean maximum load was 387.83 (±SD 115.78) N for double-screw fixation group and 306.64 (±SD 81.97) N for single-screw fixation group.

CONCLUSION

Fixation with one 4.0 mm partially threaded cancellous screw was not shown to be biomechanically inferior to fixation with two 4.0 mm partially threaded cancellous screws in an oblique fracture of the medial malleolus, supporting previous clinical studies that have shown that one screw is sufficient for fractures of the medial malleolus.

Evaluation of Contact Area and Pressure After Malreduction in Isolated Medial Malleolar Fractures With 2 mm of Displacement: A Cadaveric Study

This study was performed to evaluate the changes in contact area and pressure in the tibiotalar joint, with a 2 mm displacement after IMMF (isolated medial malleolar fracture). Ten cadavers with pairs were used to establish a situation in which IMMF occurred during ankle injury. We performed IMMF corresponding to types C and D of the Herscovici classification, and it was displaced by 2 mm. The normal group was defined as a normal tibiotalar joint, the TF (transverse fracture) group as a 2 mm transverse displacement corresponding to the Herscovici classification type C, and the OF (oblique fracture) group as a 2 mm oblique displacement corresponding to the Herscovici classification type D. We measured the contact area and pressure at the tibiotalar joint. The film was scanned and analyzed using the digital imaging software, Scion Image (Scion Crop. Frederick, MD). In normal group, the average contact area of the tibiotalar joint was 317 mm2 (IQR; interquartile range, 256; 347) and 308 mm2 (IQR, 262; 364), average pressure was 2.19 N/mm2 (IQR, 1.94; 2.27) and 2.15 N/mm2 (IQR, 2.06; 2.53). In the TF and OF groups, the average contact area of the tibiotalar joint decreased by 9% and 12%, respectively, and the average pressure increased by 8% and 14%, respectively. There was no statistical difference in peak pressure between the normal, TF, and OF groups. In the case of transverse and oblique fractures, a 2 mm displacement showed significant changes in contact area and contact pressure compared to the normal tibiotalar joint, but there were no significant changes pertaining to type, between the 2 fractures.

Prediction of anterior tibiotalar ligament injury: measurement of the angle between the deep posterior tibiotalar ligament and talus on MRI

Background

Identification of anterior tibiotalar ligament (aTTL) injury is essential because it influences the surgeon's treatment option and patient prognosis.

Purpose

To assess the diagnostic accuracy of the angle measurement between the talus and posterior tibiotalar ligament (talus-pTTL) on magnetic resonance imaging (MRI) in patients with arthroscopically proven aTTL injuries.

Material and Methods

Ankle MRI scans of 67 patients who underwent arthroscopic examination were retrospectively reviewed. The talus-pTTL angle on axial T2-weighted MRI and the medial clear space (MCS) on mortise ankle radiograph were measured. Inter-observer agreement of the measurements was calculated. Also, sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve (AUC) were the metrics of diagnostic accuracy.

Results

AUC was 0.90 for observer 1 with 78.6% sensitivity, 97.4% specificity, 88% accuracy, and 54.7° cutoff value for the talus-pTTL angle. AUC was 0.87 for observer 2 with 85.7% sensitivity, 84.6% specificity, 85.2% accuracy, and 53.7° cutoff value for the talus-pTTL angle. AUC was 0.86 with 82.1% sensitivity, 79.5% specificity, and 80.8% accuracy for observer 1 and 0.79 with 57.1% sensitivity, 92.3% specificity, and 74.7% accuracy for observer 2 for the MCS. Different MCS values and additional capabilities when complemented with the angle measurement showed an increase in diagnostic performances. Intra-observer reliability of MCS and talus-pTTL angle of the two radiologists was excellent. Inter-observer reliability of the two radiologists was excellent for both the talus-pTTL angle (0.95) and the MCS (0.85).

Conclusion

Measurement of the talus-pTTL angle showed good sensitivity, specificity, and accuracy for the evaluation of aTTL injury with excellent inter-observer reliability.

Efficacy of hook-type locking plate and partially threaded cancellous lag screw in the treatment of displaced medial malleolar fractures in elderly patients

INTRODUCTION

Traditionally, partially threaded cancellous lag screws (PTCS) are used for most medial malleolar fractures but are often challenging to execute in elderly patients because of the high risk of postoperative complications. Limited literature explores whether hook-type locking compression plates (LCPs) reliably offer better outcomes than PTCS in elderly patients. We aimed to compare the midterm radiologic and clinical outcomes between hook-type LCP and PTCS for medial malleolar fractures in an elderly population.

METHODS

We included 258 patients, aged 65 years and above, treated with either a hook-type locking plate (hook LCP group: 121 patients) or PTCS (screw group: 137 patients), and with follow-ups of at least 36 months in this retrospective study. Radiographic assessments included the union rate and interval to fracture union. Clinical assessment included the postoperative complications and revision procedures.

RESULTS

Although a significantly higher rate of comminuted fractures was observed in the hook LCP group than in the screw group (p < .001), no significant difference in the union rate was observed between the two groups (hook LCP group: 93.4% vs. screw group: 89.8%, p = .151), and a significantly shorter interval to union was observed in the hook LCP group (10.2 ± 7.0 vs. 12.3 ± 6.7 weeks, p = .015). There was a trend toward a lower rate of complications, including revision procedures, in the hook LCP group than in the screw group (19.9% vs. 28.5%, p = .107 and 6.6% vs. 13.8%, p = .074).

CONCLUSION

Hook-type LCP may be an alternative option for treating medial malleolar fractures with comminution in elderly patients.

A novel classification for medial malleolar fracture based on the 3-D reconstruction CT

Background

Fracture of the medial malleolus is one of the most frequent injuries treated surgically; however, the classification of the fracture has not attracted much attention and a good classification system is still lacking.

Methods

Consecutive cases of medial malleolus fractures were prospectively enrolled. Based on the 3-D reconstruction CT morphology and centered on the posterior colliculus of the medial malleolus, we classified the fractures into 4 types: type 1 with no involvement of the posterior colliculus, type 2 with partial involvement of posterior colliculus, type 3 with the entire involvement of posterior colliculus, and type 4 with the fracture line 4 vertically extended from the intercollicular groove to the comminuted fracture of the posterior malleolus. Statistical analyses were performed to evaluate the clinical significance of the classification.

Results

There were 273 cases prospectively enrolled. The distribution of the cases was type 1 of 12.1%, type 2 of 41.0%, type 3 of 30.0%, and type 4 of 16.8%. Statistics showed that the new classification had significant associations but did not totally depend on the classical ankle fracture classifications. Results showed that the new classification had implications in the severity of ankle fractures. From type 1 to type 4, the ankle joint was more and more unstable. Furthermore, comminuted medial malleolar fractures could be subdivided, and the new classification could provide useful information for surgical decision-making.

Conclusions

The novel classification was a useful system to describe the 3-D geometry of the fractured medial malleolus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02688-9.

Therapeutic approach to combined deltoid ligament disruption with lateral malleolus fracture: Current evidence and literature review

Ankle fractures are among the most common injuries treated by orthopaedic traumatologists. These fractures range from stable, simple injuries to complex, multi-planar unstable ones. Osseo-ligamentous structures play a paramount role in maintaining the stability of the ankle joint. The deltoid ligament is among the most important ankle static stabilizers. Rupture of this ligament along with a lateral malleolar fracture is considered by many as an unstable type of injury and usually requires surgical treatment (bi-malleolar equivalent). Left untreated, it may lead to chronic pain, loss of function and secondary arthritis. Due to lack of high-quality evidence, there are no welldefined, well-accepted criteria for the diagnosis and treatment for treating this type of injury.

Acute Deltoid Ligament Repair in Ankle Fractures

There is no consensus on whether the deltoid ligament must be repaired in ankle fractures. Recent studies have shown better early radiologic results when the deltoid ligament is repaired, but no differences in long term functional outcomes. However, there is evidence suggesting that patients with high fibular fractures or injuries with concomitant syndesmotic instability may benefit from repair. The authors recommend repairing the deltoid ligament complex in bimalleolar equivalent fractures associated with syndesmotic or gross multiligamentous instability as well as in heavier patients with greater mechanical requirements.

Acute Deltoid Ligament Repair in Ankle Fractures: Five-year Follow-up

Direct repair of deep deltoid ruptures after traumatic ankle fracture is not commonly performed. Previous studies overlook the contributions of the medial deltoid to overall ankle stability and long-term patient satisfaction. Historically, deep deltoid injuries have been addressed indirectly through syndesmotic ligament repair. This technique fails to restore, however, the anatomic function of the primary medial stabilizing structure. The oversight of direct deltoid repair may be one contributing factor to the less than optimal outcomes after ankle fractures with syndesmotic injuries. This article reports a positive response with direct deep deltoid repair, at average 5-year follow-up, with 93% positive return to normal function.

Adding deltoid ligament repair in ankle fracture treatment: Is it necessary? A systematic review

BACKGROUND

Deltoid ligament injuries are typically caused by supination-external rotation or pronation injury. Numerous ligament reconstruction techniques have been proposed; however, clear indications for operative repair have not yet been well established in the literature.

METHODS

We reviewed primary research articles comparing ORIF treatment for ankle fracture with versus without deltoid ligament repair.

RESULTS

Five studies were identified with a total of 281 patients. 137 patients underwent ORIF with deltoid repair, while 144 patients underwent ORIF without deltoid ligament repair. Clinical, radiographic, and functional outcomes, as well as complications were considered. The average follow-up was 31 months (range, 5-120).

CONCLUSIONS

Current literature does not provide clear indication for repair of the deltoid ligament at the time of ankle fracture repair. There may be some advantages of adding deltoid ligament repair for patients with high fibular fractures or in patients with concomitant syndesmotic fixation.

LEVEL OF CLINICAL EVIDENCE

III.

Transarticular external fixation versus deltoid ligament repair in treating SER IV ankle fractures: a comparative study

BACKGROUND

The topic that whether the injured deltoid ligament should be repaired when associated with ankle joint fractures is still discussed. The objective of this study was to compare the clinical effect of open reduction and internal fixation (ORIF) with deltoid ligament repair (DLR) or transarticular external fixation (TEF) in treating supination-external rotation type IV (SER IV) ankle fractures.

METHODS

Between January 2012 and December 2015, 43 patients were diagnosed as SER IV ankle fractures, 20 underwent ORIF and transarticular external fixation (TEF) without DLR (group 1), 23 were treated with ORIF and DLR (group 2). The pre- and post-operative radiographic examination were performed, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the visual analog scale (VAS), the Medical Outcomes Short Form 36-item questionnaire score (SF-36), and the ankle range of motion (ROM) were used for functional evaluation.

RESULTS

In both groups, the three scores improved significantly after surgery, but there was no significant difference between the two groups. At 6 weeks after surgery, patients in group 2 had better ankle ROM than group 1 (29.35 ± 2.033 vs. 40.35 ± 3.550, P <  0.001), but there was no difference at 12 months postoperatively. No cases of bone nonunion or post-traumatic arthritic changes were seen during the follow-up. Patients in group 1 required a shorter time to achieve fracture union than patients in group 2.

CONCLUSIONS

ORIF with TIF is an optional strategy to manage SER IV ankle fractures as it achieves comparable functional results to ORIF with DLR. It also allows patients to start relatively earlier weight-bearing and may promote fracture union.

Treatment of a Scientifically Neglected Ankle Injury: The Isolated Medial Malleolar Fracture. A Systematic Review

Isolated medial malleolar fractures are frequently encountered injuries. Literature regarding their treatment, though, is scarce and contradicting. The aim of this systematic review is to compare surgical and conservative treatment of isolated medial malleolar fractures considering complication rates and functional outcomes. PubMed, Embase, Cochrane, and CINAHL were searched for this review. Articles from 1980 or later, written in English, French, German, or Dutch, reporting any outcome of 10 or more isolated medial malleolar fractures in skeletally mature patients were included. Study quality was assessed using the Methodological Index for Non Randomized Studies (MINORS) instrument. Eighteen studies were included involving 2566 isolated medial malleolar fractures, which showed a mean (± SD) MINORS score of 8 ± 2. Mean nonunion rate was 1.7% after surgical treatment and 3.5% after conservative treatment. Overall, comparable functional outcomes were found after both treatment methods. Only 2 of the included studies reported the exact amount of fracture displacement. One study-comparing surgical and conservative treatment-showed similar functional outcomes for 1- and 2-mm displaced isolated medial malleolar fractures, and the other, a nonunion rate of 3.5% and a good mean functional outcome in 57 conservatively treated isolated medial malleolar fractures with a mean displacement of 3.8 mm. The available evidence is scarce and of low quality but suggests that conservative treatment of isolated medial malleolar fractures displaced ≤2 mm is safe. No study exists that compares surgical and conservative treatment in isolated medial malleolar fractures displaced >2 mm. Therefore, further research is needed. Until then, the eventual choice of treatment for isolated medial malleolar fractures displaced >2 mm, might be mainly dependent on the patients' characteristics and demands.

Surgical Reconstruction of an Open Medial Malleolus Fracture Using a Novel Technique: A Case Report

CASE

A 17-year-old male sustained an open fracture of the right medial malleolus (MM) with significant bone and soft tissue loss following a motor-vehicle accident. Following serial wound debridement, his ankle was effectively reconstructed with MM antiglide plate stabilization, iliac autogenous bone graft, and a free radial forearm soft tissue flap.

CONCLUSIONS

Open MM fracture with bone and soft tissue loss is rare. It is feasible to treat this injury with a novel surgical reconstruction technique involving autogenous bicortical iliac bone graft and radial forearm free flap.

Medial malleolar fractures: current treatment concepts

The medial malleolus, once believed to be the primary stabilizer of the ankle, has been the topic of conflicting clinical and biomechanical data for many decades. Despite the relevant surgical anatomy being understood for almost 40 years, the optimal treatment of medial malleolar fractures remains unclear, whether the injury occurs in isolation or as part of an unstable bi- or trimalleolar fracture configuration. Traditional teaching recommends open reduction and fixation of medial malleolar fractures that are part of an unstable injury. However, there is recent evidence to suggest that nonoperative management of well-reduced fractures may result in equivalent outcomes, but without the morbidity associated with surgery. This review gives an update on the relevant anatomy and classification systems for medial malleolar fractures and an overview of the current literature regarding their management, including surgical approaches and the choice of implants. Cite this article: Bone Joint J 2019;101-B:512-521.

Unstable Ankle Fracture Fixation Using Locked Fibular Intramedullary Nail in High-Risk Patients

Open reduction internal fixation is the gold standard for unstable ankle fracture fixation; however, complications in patients with multiple medical comorbidities are common. Intramedullary nail fixation of the fibula can help to mitigate these difficulties. A retrospective chart review was performed on all patients who underwent fixation for unstable ankle fracture between January 2015 and March 2016 at our level I trauma center. Comorbidities in the patient sample included were one or several of diabetes, renal disease, hypertension, advanced age with osteoporosis, hemorrhagic blisters, and alcoholism. The primary outcomes studied were wound complications, infections, and hardware failure or failure of fixation. Eighteen patients with a mean age of 61 years underwent fibular intramedullary nail fixation, all of whom were considered at high risk for postoperative complications. Patients presented with Weber B or C fracture patterns. All patients had syndesmotic fixation through the nail by one or two 3.5-mm tricortical screws. A medial malleolus was added if needed for stability. The average follow-up time was 291.1 (range 9 to 14 months) days. The prescribed range of time to weightbearing was 2 to 6 weeks. All patients maintained reduction of the fracture and had no wound complications. No syndesmotic screws broke postoperatively, although most patients to failed comply with the postoperative non-weightbearing restrictions. Intramedullary nailing of the fibula with syndesmotic intranail fixation is minimally invasive, quick, and provides adequate fixation strength. It offers a viable treatment option for patients at high risk for complications or who are suspected to have difficulty with follow-up or compliance.

Adverse Radiographic Outcomes Following Operative Treatment of Medial Malleolar Fractures

BACKGROUND

We initiated a retrospective study on ankle fractures to assess (1) the time needed for fracture union; (2) the incidence of adverse radiographic outcomes (AROs); (3) factors that might lead to AROs; and (4) whether AROs were associated with worse function and higher incidence of post-trauma osteoarthritis (PTOA).

METHODS

From 2007 to 2016, a total of 296 patients (169 women, 127 men; average age, 48.6 years; range, 20-84) were diagnosed with a medial malleolar fracture, whether isolated or in the setting of bi- or trimalleolar fractures, and underwent open reduction and internal fixation (ORIF) or percutaneous screw fixation (PSF). The interval to fracture union, radiographic outcomes, American Orthopaedic Foot & Ankle Society (AOFAS) score at 6 months postoperatively, and the incidence of PTOA were recorded. Risk factors were identified both in univariate and multivariate analysis. The average follow-up period was 52.0 months (range, 12-118).

RESULTS

The incidence of delayed union, nonunion, and malunion were 20.3%, 3.7%, and 4.4%, respectively. The interval to fracture union was 10.3 ± 6.4 weeks. In the multivariate analysis, the risk factors for AROs were tobacco use, vertical fractures, interposed soft tissue, and fair/poor reduction. Patients with AROs had significantly worse AOFAS score at 6 months postoperatively ( P < .001) and higher incidence of PTOA ( P < .001).

CONCLUSION

AROs of medial malleolar fractures have an underestimated incidence rate and are associated with worse ankle function and higher incidence of PTOA. Risk factors including tobacco use, vertical fractures, interposed soft tissue, poor/fair reduction should be prudently taken into consideration when treating medial malleolar fractures.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Early and mid-term results of transarticular external fixation in the treatment of supination-external rotation type IV equivalent ankle fractures

PURPOSE

To investigate the early and mid-term results of open reduction and internal fixation (ORIF) with transarticular external fixation (TEF) but no deltoid ligament repair (DLR) in the treatment of supination-external rotation type IV equivalent (SER IV E) ankle fractures (AO/OTA classification 44-B 3.1) and provide evidence for clinical practice.

METHODS

This study cohort consisted of 22 patients with SER IV E ankle fractures that underwent ORIF with TEF but no DLR between December 2011 and December 2014. There were 13 males and 9 females, mean age 38.9 years (range, 17-73 years). Eight cases involved the left side and 14 the right side. The causes of fractures included road traffic accidents (11 cases), falling from height (6 cases) and sports injuries (5 cases). The mean period of hospitalization was 9.8 days (range, 6-14 days). For all the patients, MRI and three-dimensional CT were done before surgery and X-rays done preoperatively and during follow-ups. The external frame was kept for 8-10 weeks. The preoperative American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was 56.86 ± 4.400, the Medical Outcomes Short Form 36-item (SF-36) questionnaire score was 57.41 ± 4.102 and the visual analog score (VAS) was 5.50 ± 1.058. Patients' main complaints about inconvenience of daily life were also recorded.

RESULTS

All the 22 patients were followed up for 24-63 months (mean, 33.6 months). None of them developed nonunion during the follow-up; pin site infection was observed in one patient and posttraumatic osteoarthritis in another. At the final follow-up, the average AOFAS score, SF-36 score and VAS score were respectively 90.59 ± 5.096, 79.59 ± 5.394 and 1.82 ± 1.181, which were significantly improved compared with the preoperative data (t = 26.221, p < 0.001; t = 11.910, p < 0.001; t = 11.571, p < 0.001). The therapeutic effect was excellent in 13 cases, good in 7 cases and fair in 2 cases, with a good-excellent rate of 90.9%. Patients' main complaints were inconvenience of clothing (17 cases) and extremity cleaning (5 cases).

CONCLUSION

In the treatment of SER IV E ankle fractures, ORIF with TEF but no DLR can achieve satisfactory outcome, but long-term effect should be confirmed by large sample randomized controlled trials.

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.