Investigating causal mechanisms in randomised controlled trials

INTRODUCTION

In some randomised trials, the primary interest is in the mechanisms by which an intervention exerts its effects on health outcomes. That is, clinicians and policy-makers may be interested in how the intervention works (or why it does not work) through hypothesised causal mechanisms. In this article, we highlight the value of understanding causal mechanisms in randomised trials by applying causal mediation analysis to two randomised trials of complex interventions.

MAIN BODY

In the first example, we examine a potential mechanism by which an exercise programme for rheumatoid arthritis of the hand could improve hand function. In the second example, we explore why a rehabilitation programme for ankle fractures failed to improve lower-limb function through hypothesised mechanisms. We outline critical assumptions that are required for making valid causal inferences from these analyses, and provide results of sensitivity analyses that are used to assess the degree to which the estimated causal mediation effects could have been biased by residual confounding.

CONCLUSION

This paper demonstrates how the application of causal mediation analyses to randomised trials can identify the mechanisms by which complex interventions exert their effects. We discuss methodological issues and assumptions that should be considered when mediation analyses of randomised trials are used to inform clinical practice and policy decisions.

Selective fixation of the medial malleolus in unstable ankle fractures

BACKGROUND

Whilst the lateral malleolus appears to be crucial in controlling anatomical reduction of the talus, the role of the medial malleolus is less clear. Medial sided complications including infection, damage to local structures and symptomatic hardware are not without morbidity. This study compares the outcomes of patients with bimalleolar or trimalleolar ankle fractures who underwent fibular nail stabilisation with or without medial malleolar fixation.

METHODS

From a prospective single-centre trauma database, we identified 342 patients over a nine-year period who underwent fibular nail insertion to stabilise a bimalleolar or trimalleolar ankle fracture. Isolated lateral malleolar fractures were excluded. Demographic data, clinical outcomes, radiographic evaluation, return to work and sport, and patient reported outcomes, including Olerud-Molander Ankle Score (OMAS), EuroQol-5D (EQ-5D) and Manchester-Oxford Foot Questionnaire (MOXFQ) were collected.

RESULTS

This study included 247 patients with a mean age of 66.7 years (range, 25-96 years), of whom 200 were female (81%). Medial malleolar fixation was not performed in 54 cases (22%). There was no significant difference between groups with respect to failure of fixation (p = 0.634) or loss of talar reduction (p = 0.157). No patient required surgery for a symptomatic medial malleolar non-union. Medial sided complications occurred in 32 (16%) of the fixation group, of whom 20 (10%) required further surgery. At a mean mid-term follow-up of 4.8 years (range, 8 months - 9 years) there was no significant difference between the non-fixation and fixation groups with respect to the median OMAS (85 vs 80; p = 0.885) or median EQ-5D (0.80 vs 0.81; p = 0.846). Patient satisfaction was not significantly different between the two groups (85/100 vs 87/100; p = 0.410).

CONCLUSION

Non-operative management of the medial malleolar component of an unstable ankle fracture treated with a fibular nail may reduce the rate of post-operative complications without compromising the patient reported outcome.

The diagnosis and treatment of isolated type B fibular fractures: Results of a nationwide survey

INTRODUCTION

In isolated Weber B fractures (type B fibular fractures), ruling out instability is critical for safe conservative treatment. In fractures without evident medial injury, additional diagnostics like MRI scan or gravity stress test should be done to differentiate between a stable and unstable fracture. The aim of the current study is to gain more insight in current practice and treatment of type B fractures by Dutch trauma- and orthopaedic surgeons.

MATERIALS & METHODS

In December 2017 and January 2018, 559 trauma surgeons were invited by email to join an online survey. This survey consisted of questions regarding diagnostics and treatment of isolated distal fibula fractures. Also, respondents were asked to state their preferred treatment of eight separate cases.

RESULTS

In total, 161 surgeons participated, covering 68 different hospitals in the Netherlands. Of them, 32.0% treat more than 30 ankle fractures a year. Based on regular mortise radiographs, 13.6% of the respondents chose surgical treatment in case of a medial clear space (MCS) > 4 mm, 33.8% in case of a MCS > 6 mm and 45.5% in case of a MCS > 4 mm in addition to the MCS ≥ superior clear space + 1 mm. Moreover, 18.2% make use of additional diagnostics (43.9% repeat mortise view after a week, 16.6% weight bearing radiograph, 8.6% gravity stress view, 7.9% exorotation radiograph, 6.5% MRI scan, 0.7% ultrasound, 16.8% other) and 8% establishes their decision not based on the mortise radiograph. Fibular dislocation of ≥ 2 mm was used as an indication for surgical treatment by 69%. Of them, 56% decides to treat surgically in these cases, even with proven medial stability.

CONCLUSION

Many surgeons treat type B fibular fractures with a MCS > 4 mm at mortise view surgically, even without proven medial injury. Rarely, additional diagnostics as MRI or gravity stress test are performed in cases with a MCS 4-6 mm. Consequently many stable ankle fractures are treated operatively unnecessarily.

Trimalleolar Fracture-Dislocation of the Ankle with a Double Fragment of the Medial Malleolus: A Separate Fracture Subtype?

INTRODUCTION

Lauge-Hansen classification for ankle fractures is helpful in directing the management of the fracture and has got prognostic significance. However, trimalleolar fractures with double medial malleolar fracture are not yet described.

CASE REPORT

Two cases of trimalleolar fracture-dislocation of the ankle with a double fracture of the medial malleolus are reported. Both of them had a Weber B fracture of the lateral malleolus, accompanied by a posterior dislocation of the ankle and a fracture of the posterior malleolus. The medial malleolus though presented an interesting variation, a large vertical or oblique fragment was combined with a small horizontal fragment of its tip.

CONCLUSION

We propose a separate subtype in the Lauge-Hansen classification of supination with combined external rotation and adduction when this pattern of the medial malleolus is accounted. Awareness of this fracture pattern will help better pre-operative planning.

Discordant pattern of peripheral fractures in diabetes: a meta-analysis on the risk of wrist and ankle fractures

To clarify if the peripheral microarchitectural abnormalities described in diabetics have clinical consequences, we evaluated the risk of wrist and ankle fractures. The meta-analysis resulted in an increase in the risk of ankle fractures and a decrease in wrist fractures risk, suggesting that microarchitecture may not be the major fracture determinant.

INTRODUCTION

There is evidence for an increase in the risk of hip fractures in diabetes (both in type 1 and 2), but the risk is not established for other skeletal sites. Microarchitecture evaluations have reported a decrease in volumetric bone mineral density and an increase in cortical porosity at the radius and tibia. To investigate if there is a clinical consequence for these microarchitectural abnormalities, we performed a systematic review and meta-analysis on the risk of ankle and wrist fractures in diabetes.

METHODS

Medline and Embase were searched using the terms 'diabetes mellitus', 'fracture', 'ankle', 'radius' and 'wrist'. Relative risks and 95% confidence intervals were calculated using random effects model.

RESULTS

For ankle fractures, six studies were selected including 2,137,223 participants and 15,395 fractures. For wrist fractures, 10 studies were eligible with 2,773,222 subjects and 39,738 fractures. The studies included men and women, ages 20 to 109 years for the wrist and 27 to 109 years for the ankle. The vast majority of subjects had type 2 diabetes. Diabetes was associated with an increase in the risk of ankle fractures (RR 1.30 95%CI 1.15-1.48) and a decrease in wrist fractures (RR 0.85 95%CI 0.77-0.95). In the studies that reported body mass index (BMI), the mean values were 10% higher in the diabetic groups than controls.

CONCLUSION

The risk of fractures is increased in diabetes at the ankle and decreased at the wrist. The same pattern is observed in obesity. Although bone microarchitectural features are different in obesity and diabetes, the epidemiology of peripheral fractures is similar in both diseases suggesting that microarchitecture may not be the major determinant of peripheral fractures in these populations.

Return to car driving is safe 6 weeks after operative treatment of right ankle fractures

BACKGROUND

There is no clear consensus on when patients with surgically treated right ankle fractures can return to car driving, or how best to assess their fitness to drive. Through a rigorous driving assessment program consisting of both off-road and on-road tests, we aim to determine if these patients are able to pass a standard driving test, even before weight bearing has been initiated.

METHODS

A prospective grant-funded (Supported by AOTrauma Asia Pacific Ref: AOTAP12-17) clinical study was conducted. Patients aged 25-65 years who underwent surgery for right ankle fractures and held a valid motorcar driving license were recruited in a single institution from 2013 to 2015. The surgeon and a specialist occupational therapist assessed the patients at 2, 6 and 12 weeks post-surgery. A Short Musculoskeletal Functional Assessment (SMFA) Questionnaire was administered and the brake reaction time was measured using a driving simulator. Patients who met the minimal criteria were then subjected to a full on-road driving test in a real-world environment with a driving instructor. A follow-up telephone questionnaire was administered at least 6 months after return to driving to determine if patients had returned to driving safely.

RESULTS

A total of 23 patients (8 females, 15 males) were recruited. The mean age was 42.8 (± 12.9) years. There was a significant improvement in the SMFA (p < 0.05) and braking time (p < 0.05) at 6 and 12 weeks post-surgery. Nearly all (91%) patients passed the on-road driving test at 6 weeks, before their fractures had healed or weight bearing was initiated. The questionnaire administered at least 6 months after return to driving revealed that all patients had returned to regular driving safely.

CONCLUSION

We conclude that patients with isolated, surgically treated right ankle fractures can successfully pass a standard driving test at 6 weeks post-surgery, even before weight bearing has been initiated. We also showed that the ability to drive correlates with improvements in the SMFA scores and braking times.

LEVEL OF EVIDENCE

II.

Does routinely repairing deltoid ligament injuries in type B ankle joint fractures influence long term outcomes?

Deltoid ligament reconstruction following type B ankle fractures continues to generate a vivid discussion amongst trauma surgeons. There is a difference of opinion as to whether operative or non operative treatment should prevail. We therefore conducted a prospective comparative cohort study to determine whether it is necessary to routinely repair the injured deltoid ligaments. 41 Type B ankle joint fracture patients were enrolled, all the patients were associated with deltoid ligament ruptures and lateral/posterior-lateral dislocation of talus. After fixation of the lateral malleolus fracture, 12 patients were treated by superficial deltoid ligaments repairing, 16 patients with deep components augmentation, 13 patients had no direct surgical intervention. In the deep components group, the planter and the dorsi flexion was 3.2° (0-10°) and 8.8° (0-15°) less than the normal side. In the superficial components group, plantar and dorsi flexion was 0.8° (0-5°) and 4.2° (0-15°) less than the normal side. In the non-repairing group, the plantar and dorsi flexion was 2.4° (0-10°) and 5.6° (0-20°) less than the normal side. Overall, no significant statistical difference was observed comparing the 3 groups. In addition, no statistically significant inter-group differences were evident in terms of measurement of the ankle medial clear space and the clinical and functional outcomes recorded. In conclusion, the results of this study do not support routine exposure and repairing of the injured deltoid ligaments.

Fixation of unstable ankle fractures using a long hindfoot nail

BACKGROUND

Management of fragility fractures of the ankle is challenging. Non-operative treatment often requires significant periods of reduced weight bearing. Operative fixation is difficult due to osteoporotic bone and poor soft tissues. The aim of this study was to review the initial experience of treating unstable ankle fractures with a retrograde femoral nail used as a long tibiotalocalcaneal nail.

PATIENTS AND METHODS

Sixteen patients were treated from January 2014 until November 2017. Mean age was 73 (50-96) and twelve of the sixteen patients were female. All patients had three or more co-morbidities and an American Society of Anaesthesiologists score of 3. All patients had unstable ankle fracture configurations and were classified using the AO classification.

RESULTS

All patients regained baseline mobility by final follow-up (mean 21 months follow-up). Four of the sixteen patients died within 12 months of surgery. There were no wound complications or deep infections. There were no cases of metalwork failure or peri-prosthetic fracture.

DISCUSSION

Use of a retrograde femoral nail has been shown to be a safe and effective option in the management of unstable ankle fractures in elderly and frail patients. This technique may lead to lower wound complications compared to traditional fixation techniques and allows earlier mobilisation.

Microfracture provides better clinical results than debridement in the treatment of acute talar osteochondral lesions using arthroscopic assisted fixation of acute ankle fractures

PURPOSE

Ankle arthroscopy is a useful tool for detection and treatment of accompanying intraarticular pathologies in acute ankle fractures. The purpose of this study was to compare the treatment results of talus osteochondral lesions (OLT) with debridement and microfracture in arthroscopy assisted surgery of acute ankle fractures.

METHODS

Eleven consecutive patients who were treated with arthroscopic acute debridement and 14 consecutive patients who were treated with arthroscopic acute microfracture in the treatment of ankle fracture were included in the study. All patients were controlled clinically and radiologically in the postoperative period. Ankle pain was evaluated with the visual analog score (VAS), ankle functions were assessed with American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS), and osteoarthritic changes were analyzed with Van Dijk score.

RESULTS

There was no significant difference between the groups in terms of age, gender, injury side and trauma mechanism (n.s). Mean time to surgery, fracture healing duration, first weight-bearing and full weight-bearing, follow-up period and Van Dijk score were all similar in both groups (n.s). The AOFAS score and VAS activity score were statistically significantly better in the microfracture group (p = 0.044 and p = 0.001).

CONCLUSIONS

The clinical relevance of the present study is to define the acute treatment of the first osteochondral damage that occurred simultaneously with ankle fracture, to improve postoperative functional outcomes and to prevent post-traumatic osteoarthritis. Both debridement and microfracture yield good functional outcomes in the second year of the treatment. Microfracture ensures significantly more successful clinical results than debridement.

LEVEL OF EVIDENCE

Level III.

When and how to operate the posterior malleolus fragment in trimalleolar fractures: a systematic literature review

OBJECTIVES

Whether or not and how to fixate the posterior malleolus fracture seems to depend on the fracture fragment size and its amount of dislocation, but clear guidelines for daily practice are lacking. In this review, we summarize the literature on preferred treatment of the posterior fragment in trimalleolar fractures.

METHODS

A systematic review of publications between January 1995 and April 30 2017 on this topic in the PubMed, Embase, and Cochrane databases was performed according to the PRISMA statement.

RESULTS

Seventeen (2 prospective and 15 retrospective) of the 180 identified studies were included. Six studies report on indications for fixation of posterior malleolus fracture fragments. Eleven studies compare different fixation approaches and techniques for the posterior fragment. Meta-analysis was not possible due to varying fixation criteria and outcomes. There was no clear association between posterior fragment size and functional outcome or development of osteoarthritis. The non-anatomical reduction of the fragment was of more influence on outcome. Radiological and functional outcome was better after open reduction and internal fixation via the posterolateral approach than after percutaneous anterior-to-posterior screw fixation.

CONCLUSION

The posterior fragment size is not a clear indication for its fixation. A step-off, however, seems an important indicator for developing posttraumatic osteoarthritis and worse functional outcome. Posterior fragments involving the intra-articular surface need to be reduced and fixated to prevent postoperative persisting step-off. Furthermore, fixation of the posterior malleolus via an open posterolateral approach seems superior to percutaneous anterior-to-posterior fixation. However, these results need to be confirmed in a prospective comparative trial.

LEVEL OF EVIDENCE

Therapeutic level II.

Fixation of medial malleolar fractures with magnesium bioabsorbable headless compression screws: short-term clinical and radiological outcomes in eleven patients

OBJECTIVE

The purpose of this retrospective study was to evaluate the outcome of medial malleolar fractures treated with magnesium (MgYREZr) bioabsorbable compression screw fixation.

MATERIALS AND METHODS

Eleven patients with a medial malleolar fracture (either isolated or accompanied by bimalleolar or trimalleolar ankle fractures) who were treated with magnesium bioabsorbable compression screws between 2015 and 2016 in our hospital were retrospectively evaluated. Patients were monitored with a mean follow-up of 17.3 ± 4.1 months (range 12-24 months). The mechanism of injury was ground level falls in all patients. All fractures were classified as closed fractures. American Orthopedic Foot and Ankle Society's (AOFAS) scale and the visual analog scale (VAS) were used to evaluate the clinical results during the final follow-up. Bone union and a possible loss of reduction were assessed with serial radiographs. Potential complications including revision surgery and infection were recorded and reported.

RESULTS

There were 11 patients (4 female, 7 male) with a mean age of 41 ± 21.9 years (range 20-78 years). Six patients had Herscovici type C and five patients had type B fractures. At the final follow-up the mean AOFAS score was 94.9 ± 5.7 points (range 85-100 points) and the mean VAS score was 0.4 ± 1.2 points (range 0-4 points). Radiographic solid union was achieved in all cases. No complications were seen during the follow-up. No patients required implant removal or revision surgery.

CONCLUSIONS

This is the first study that investigates the use of bioabsorbable magnesium compression screws in medial malleolar fractures. The results of this study revealed that fixation of medial malleolar fractures with bioabsorbable magnesium compression screws provides adequate fixation with good functional results.

LEVEL OF EVIDENCE

Level IV, therapeutic, retrospective case series.

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.

Nurse-initiated radiographic-test protocol for ankle injuries: A randomized controlled trial

INTRODUCTION

Nurse-initiated radiographic-test protocol was compared with usual practice in reducing unnecessary ankle and foot radiographic-test requests and shortening patients' length of stay (LOS) in an emergency department (ED) by reducing their waiting time for physician reassessment.

METHODS

Patients with ankle injuries were enrolled in an unblinded randomized controlled trial. Participants were randomized to receive either the protocol (n = 56) or usual practice (n = 56). Primary outcome was the proportion of radiographic-test requests. Secondary outcomes were the proportion of fractures detected and patients' LOS and waiting times.

RESULTS

The proportions of ankle and foot radiographic tests requested by triage nurses implementing the Ottawa Ankle Rules (OARs) in protocol group were smaller than those requested by physicians using their expertise in usual practice group. The proportions of malleolar and midfoot fractures detected by triage nurses implementing the OARs in protocol group were higher than those detected by physicians using their expertise in usual practice group. Patients' LOS and waiting time from consultation to discharge in protocol group were shorter than those in usual practice group.

CONCLUSIONS

Implementing the nurse-initiated radiographic-test protocol reduced unnecessary ankle and foot radiographic-test requests and shortened patients' LOS in the ED by reducing their waiting time for physician reassessment.

Outpatient Management of Ankle Fractures

Interest in outpatient orthopedic surgery has been fueled by provider desire to control costs and development of rapid recovery protocols. Open reduction and internal fixation (ORIF) is a commonly elected treatment strategy for ankle fracture that may be performed in an outpatient setting. Lessons on cost-savings of the outpatient model in orthopedics can be learned in total joint replacement and spine surgery. Moreover, in properly selected patients, outpatient ORIF has been shown to be comparably safe. Reasons for admission of the surgically managed patient with ankle fractures, including concern for surgical delay and additional social factors, warrant further investigation.

Supination-external rotation ankle fractures: analysis of clinical results after syndesmotic screw removal

Objective

To evaluate the postoperative results of patients with supination-external rotation ankle fractures who underwent syndesmotic screw (SS) removal.

Methods

Retrospective cohort study assessing the late postoperative results of 35 patients operated from January 2013 to June 2015. Patients undergoing treatment of rupture of the distal tibiofibular syndesmosis with SS fixation and who did not have any concomitant surgical injuries in sites other than the ankle were included. Patients who did not complete appropriate follow-up after surgery were excluded from the study.

Results

There was no statistical significant difference in the evaluated outcomes among the patients who had their SS removed and those who remained with the SS.

Conclusion

SS removal did not significantly alter the clinical results of patients surgically treated with SS for supination-external rotation fractures.

Is osteoporosis a risk factor for ankle fracture?: Comparison of bone mineral density between ankle fracture and control groups

Objectives

There remains controversy over osteoporotic feature of the ankle. Therefore, we investigated the possibility of the existence of a relationship between axial bone mineral density (BMD) in patients with ankle fracture group with that of the normal population in Korea under control of other confounding factors such as body mass index (BMI).

Methods

This study retrospectively reviewed medical records of patients who were treated in our institution from 2005 to 2015. A comparative analysis was carried out between 116 patients with ankle fracture (ankle fracture group) and 113 patients admitted with other orthopedic reasons (control group). Sex, age, energy level of trauma, and BMI were analyzed as variables affecting axial BMD.

Results

Age and sex of ankle fracture group were not different from them of control group (P = 0.968 and P = 0.870, respectively). BMI of ankle fracture group was higher than that of control (P = 0.029). The other variables showed no differences between the 2 groups. The energy level of trauma in ankle fracture group was related to only BMI (P = 0.013).

Conclusions

Axial BMD of ankle fracture patients showed no difference from that of a control group in Korean population. The occurrence of ankle fracture is affected by only BMI rather than axial BMD. Evaluation of osteoporosis for patients with ankle fracture should be considered separately.

Ankle fracture controversies: Do the foot and ankle specialists have a different vision?

OBJECTIVE

To analyse the differences in the management of ankle fractures between orthopaedic/trauma surgeons and foot and ankle specialists.

MATERIAL AND METHOD

An e-mail survey was performed asking some of the country's orthopaedic surgeons controversial questions regarding the analysis of 5 clinical cases of different ankle fractures.

RESULTS

Seventy-two surgeons responded to the questionnaire (response rate of 24.2%): 37 foot and ankle specialists and 35 non-specialist orthopaedic surgeons. For trimalleolar fracture, 40.5% of the specialists would request a computed tomography scan compared to 14% of the non-specialists (P=.01). Ninety-four percent of all the respondents would synthesise the posterior malleolus; 91% of the non-specialists would use an antero-posterior approach, either with a plate or with screws (P=.006). No differences were found between groups in the treatment of syndesmotic injuries (P>.05). For trans-syndesmotic fracture (Weber B) with signs of medial instability, 54% of the non-specialists would revise the internal lateral ligament compared to only 32% of the specialists (P=.06).

CONCLUSIONS

The foot and ankle specialists ask for more complementary tests to diagnose ankle fractures. In turn, they use a greater diversity of surgical techniques in synthesis of the posterior malleolus (posterior plate) and the medial malleolus (cerclage wires). Finally, they indicated a lower revision rate of the internal lateral ligament.

Ankle fracture - Correlation of Lauge-Hansen classification and patient reported fracture mechanism

INTRODUCTION

The genetic Lauge-Hansen classification is used for reconstruction of the mechanism of ankle injury. In this study, we addressed the question of agreement between the mechanism of the fracture as postulated by the Lauge-Hansen classification and mechanism reported by the patient in rotational ankle fractures.

MATERIAL AND METHODS

Radiographs of 78 patients with acute malleolar fractures were analyzed and compared with fracture mechanisms reported by these patients.

RESULTS

The patient reported mechanisms were in concordance with the mechanism deducted from the X-rays in 49% of cases. Only 17% of patients who recalled a pronation trauma actually had radiographs classified as pronation fractures while 76% of patients who recalled a supination trauma were also radiographically classified as having sustained supination type fractures.

CONCLUSION

The Lauge-Hansen classification should be used with caution for determining the actual mechanism of injury as it was able to predict the patient reported fracture mechanism in less than 50% of cases. A substantial percentage of fractures appearing radiographically as supination type injuries may have been actually produced by a pronation fracture mechanism.

What's new in ankle fractures

The diagnosis and treatment of ankle fractures has evolved considerably over the past two decades. Recent topics of interest have included indications for operative treatment of isolated lateral malleolus fractures, need for fixation of the posterior malleolus, utilization of the posterolateral approach, treatment of the syndesmosis, and the potential role of fibular nailing. In this update, we concisely review these topics and what to expect in the future literature.

Trajectories in quality of life of patients with a fracture of the distal radius or ankle using latent class analysis

Purpose

This prospective study aimed to identify the different trajectories of quality of life (QOL) in patients with distal radius fractures (DRF) and ankle fractures (AF). Secondly, it was examined if subgroups could be characterized by sociodemographic, clinical, and psychological variables.

Methods

Patients (n = 543) completed the World Health Organization Quality of Life assessment instrument-Bref (WHOQOL-Bref), the pain, coping, and cognitions questionnaire, NEO-five factor inventory (neuroticism and extraversion), and the state-trait anxiety inventory (short version) a few days after fracture (i.e., pre-injury QOL reported). The WHOQOL-Bref was also completed at three, six, and 12 months post-fracture. Latent class trajectory analysis (i.e., regression model) including the Step 3 method was performed in Latent Gold 5.0.

Results

The number of classes ranged from three to five for the WHOQOL-Bref facet and the four domains with a total variance explained ranging from 71.6 to 79.4%. Sex was only significant for physical and psychological QOL (p < 0.05), whereas age showed significance for overall, physical, psychological, and environmental QOL (p < 0.05). Type of treatment or fracture type was not significant (p > 0.05). Percentages of chronic comorbidities were 1.8 (i.e., social QOL) to 4.5 (i.e., physical QOL) higher in the lowest compared to the highest QOL classes. Trait anxiety, neuroticism, extraversion, pain catastrophizing, and internal pain locus of control were significantly different between QOL trajectories (p < 0.05).

Conclusions

The importance of a biopsychosocial model in trauma care was confirmed. The different courses of QOL after fracture were defined by several sociodemographic and clinical variables as well as psychological characteristics. Based on the identified characteristics, patients at risk for lower QOL may be recognized earlier by health care providers offering opportunities for monitoring and intervention.

Comparison between carbon-peek plate and conventional stainless steal plate in ankle fractures. A prospective study of two years follow up

INTRODUCTION

The aim of our study is to compare the clinical and radiological outcomes of the treatment of distal fibular fracture with the traditional stainless steel or the new radiolucent CFR-PEEK plates. The hypothesis is that there are no differences in clinical and radiological outcomes at the final follow-up between the two fixation devices.

METHODS

All consecutive patients aged from 18 or over, who had undergone operative treatment for malleolar fracture between 2013 and 2014, have been included in the study. 87 were available for the study. The patients were assigned to group A (47 patients, radiolucent plate group) and group B (41 patients, stainless steal plate group). At 6, 12 and 24 months all patients were prospectively reviewed with radiographic and clinical evaluations (OMAS scale, AOFAS, VAS, ROM).

RESULTS

The groups were homogenous with regard to age, gender, BMI, dominance and disease duration. The mean follow-up was 23+/-2 months. The mean waiting time to operation was 2.94days (SD 2.74) (range 0.2-6.8). Statistical analysis showed no difference (p>0.05) about the VAS, OMAS, AOFAS and ROM evaluation at 6, 12 and 24 month follow-up between two groups. Radiographic evaluation showed no difference between two groups at all the follow-up with similar results obtained with the two fixation devices.

DISCUSSION

Our results showed a substantial equivalence of the two fixation devices at 6, 12 and 24 month of clinical and radiographic follow-up. Fixation of the lateral malleolus fractures with a CFR-PEEK plate provides satisfying clinical and radiographic results after 2 years of follow-up. These results are comparable to those achieved with conventional plates.

Management of acute injuries of the tibiofibular syndesmosis

The syndesmosis is important for ankle stability and load transmission and is commonly injured in association with ankle sprains and fractures. Syndesmotic disruption is associated with between 5 and 10% of ankle sprains and 11-20% of operative ankle fractures. Failure to recognize and appropriately treat syndesmotic disruption can portend poor functional outcomes for patients; therefore, early recognition and appropriate treatment are critical. Syndesmotic injuries are difficult to diagnose, and even when identified and treated, a slightly malreduced syndesmosis can lead to joint destruction and poor functional outcomes. This review will discuss the relevant anatomy, biomechanics, mechanism of injury, clinical evaluation, and treatment of acute injuries to the ankle syndesmosis.

Identification of fracture zones and its application in automatic bone fracture reduction

BACKGROUND AND OBJECTIVE

The preoperative planning of bone fractures using information from CT scans increases the probability of obtaining satisfactory results, since specialists are provided with additional information before surgery. The reduction of complex bone fractures requires solving a 3D puzzle in order to place each fragment into its correct position. Computer-assisted solutions may aid in this process by identifying the number of fragments and their location, by calculating the fracture zones or even by computing the correct position of each fragment. The main goal of this paper is the development of an automatic method to calculate contact zones between fragments and thus to ease the computation of bone fracture reduction.

METHODS

In this paper, an automatic method to calculate the contact zone between two bone fragments is presented. In a previous step, bone fragments are segmented and labelled from CT images and a point cloud is generated for each bone fragment. The calculated contact zones enable the automatic reduction of complex fractures. To that end, an automatic method to match bone fragments in complex fractures is also presented.

RESULTS

The proposed method has been successfully applied in the calculation of the contact zone of 4 different bones from the ankle area. The calculated fracture zones enabled the reduction of all the tested cases using the presented matching algorithm. The performed tests show that the reduction of these fractures using the proposed methods leaded to a small overlapping between fragments.

CONCLUSIONS

The presented method makes the application of puzzle-solving strategies easier, since it does not obtain the entire fracture zone but the contact area between each pair of fragments. Therefore, it is not necessary to find correspondences between fracture zones and fragments may be aligned two by two. The developed algorithms have been successfully applied in different fracture cases in the ankle area. The small overlapping error obtained in the performed tests demonstrates the absence of visual overlapping in the figures.

Posterior Malleolar Fractures: Changing Concepts and Recent Developments

Injuries to the posterior malleolus are of prognostic relevance in ankle fracture-dislocations. The three-dimensional outline of the fragments as reflected by computed tomography classification, involvement of the fibular notch, and the presence of intercalary fragments seem to be of greater therapeutic relevance than the size of the fragment and amount of the articular surface involved. Operative treatment aims at reconstruction of the posterior tibial plafond, the fibular notch, and the integrity of the posterior inferior tibiofibular syndesmosis. Direct open reduction and fixation of posterior malleolus fragments via posterior approaches is biomechanically more stable than indirect reduction and anteroposterior screw fixation.