Hindfoot kinematics and kinetics - A combined in vivo and in silico analysis approach.

BACKGROUND: The complex anatomical structure of the foot-ankle imposes challenges to accurately quantify detailed hindfoot kinematics and estimate musculoskeletal loading parameters. Most systems used to capture or estimate dynamic joint function oversimplify the anatomical structure by reducing its complexity. RESEARCH QUESTION: Can four dimensional computed tomography (4D CT) imaging in combination with an innovative foot manipulator capture in vivo hindfoot kinematics during a simulated stance phase of walking and can talocrural and subtalar articular joint mechanics be estimated based on a detailed in silico musculoskeletal foot-ankle model. METHODS: A foot manipulator imposed plantar/dorsiflexion and inversion/eversion representing a healthy stance phase of gait in 12 healthy participants while simultaneously acquiring 4D CT images. Participant-specific 3D hindfoot rotations and translations were calculated based on bone-specific anatomical coordinate systems. Articular cartilage contact area and contact pressure of the talocrural and subtalar joints were estimated using an extended foot-ankle model updated with an elastic foundation contact model upon prescribing the participant-specific rotations measured in the 4D CT measurement. RESULTS: Plantar/dorsiflexion predominantly occurred at the talocrural joint (RoM 15.9±3.9°), while inversion/eversion (RoM 5.9±3.9°) occurred mostly at the subtalar joint, with the contact area being larger at the subtalar than at the talocrural joint. Contact pressure was evenly distributed between the talocrural and subtalar joint at the beginning of the simulated stance phase but was then redistributed from the talocrural to the subtalar joint with increasing dorsiflexion. SIGNIFICANCE: In a clinical case study, the healthy participants were compared with four patients after surgically treaded intra-articular calcaneal fracture. The proposed workflow was able to detect small but meaningful differences in hindfoot kinematics and kinetics, indicative of remaining hindfoot pathomechanics that may influence the onset and progression of degenerative joint diseases.

3D imaging added value in the treatment and diagnosis of displaced intra-articular calcaneal fractures (DIACF): measuring the orientation of the posterior talo-calcaneal facet in the space.

PURPOSE: Measure the reduction quality of calcaneal fractures on 3 D segmented images. METHODS: The Ethics Review Board approved this study and written informed consent was collected from all patients. Bilateral CT scans of fifty-four patients with unilateral displaced calcaneal fracture were obtained before and after osteosynthesis. Orientation angle of the posterior subtalar joint facet (PTC) of displaced intra-articular calcaneal fractures of 54 patients was measured on segmented 3 D images before and after surgery and compared to the uninjured side. This orientation angle (OAC) is the average of every normal vector of each point of the PTC, as compared to the main calcaneal axis (calculated by first principal component analysis). The PTC is a well-known anatomical structure, relatively easy to identify on 3 D imaging. RESULTS: This OAC angle was low before surgery (mean= 95°, std dev= 6°), statistically significantly different from the uninjured side value, p < 0.001. The OAC angle of the operated bone was nearly equal to the uninjured side (mean= 103°, std dev= 5°), without any statistically significant difference between postoperative values and uninjured side values. We found linear correlation between the quality of the reduction when assessed with this OAC and the functional score (AOFAS) (Adjusted R2=0.62, p = 0.04). CONCLUSIONS: This angle seems to be useful to quantify the quality of the operative reduction of displaced intra-articular calcaneal fractures.

Accelerated Rehabilitation in Non-operative Management of Acute Achilles Tendon Ruptures: A Systematic Review and Meta-analysis.

The optimal treatment and rehabilitation strategy for Achilles tendon ruptures is still under debate. There is a paradigm shift toward early mobilization and weightbearing. We examined the treatment effect of accelerated functional rehabilitation in nonoperative management of acute Achilles tendon ruptures. A systematic search of PubMed, EMBASE, and Web of Science databases for articles comparing accelerated versus delayed rehabilitation in the nonoperative management of acute Achilles tendon rupture was performed. Outcomes of interest were Achilles tendon rupture score (ATRS) (standardized patient-reported instrument related to symptoms and physical activity after treatment of an acute Achilles tendon rupture), rerupture rate, strength, range of motion, return to work, and sports. A total of 2001 articles were identified using our search strategy. We included 6 randomized controlled trials of interest. Although the concept of accelerated rehabilitation has gained popularity in recent years, no statistically significant differences could be revealed in any of the outcomes of interest. We performed a meta-analysis on the following outcomes: ATRS (mean difference -0.93 95% confidence interval [CI] -6.01 to 4.14), Rerupture rate (odds ratio [OR] 0.97, 95% CI: 0.46-2.03), Return to sports (OR 1.31, 95% CI 0.76-2.25), Return to work (mean difference 5.24, 95% CI to -12.04 to 22.51). The treatment effect of accelerated rehabilitation in nonoperatively treated patients seems to be small. However, we recommend accelerated rehabilitation for all conservatively treated patients, because it is a safe option and no detrimental effects have been described in the literature. Furthermore, many patients prefer this type of rehabilitation to avoid the practical disadvantages of prolonged immobilization.

Three-Dimensional Imaging of Displaced Intra-articular Calcaneal Fractures Correlates With the Perioperative Diagnosis.

BACKGROUND: Intra-articular calcaneal fractures are complex injuries, and CT imaging has become the standard imaging in the preoperative assessment. Most classifications of these fractures are CT-based but have been associated with limited interobserver agreement. Three-dimensional imaging has become widely available and may give a better perspective but often with 1 image only. There is not much evidence of the added value of this imaging, compared with the CT imaging. METHODS: Eight experienced trauma surgeons assessed 28 different intra-articular calcaneal fractures, on conventional radiology (CR), CT, and 3-D imaging. All had extensive experience in the diagnosis and treatment of this difficult injury. The main questions concerned Sanders classification, the severity of the injury and the difficulty of the operative procedure, choice of approach, and choice of procedure. RESULTS: The classical 2-D CT imaging of the fractures were associated with a higher Sanders classification ranking, compared with the 3-D imaging scores. However, the interobserver agreement, as measured by the Fleiss kappa, was low for all 3 imaging modalities. We found more frequent Sanders III and IV classifications with CT scan imaging compared with 3-D imaging or CR. The scores obtained after assessing 3-D imaging were also not statistically significantly different from the scores of a consensus achieved by 2 authors and based on the 3 imaging modalities and the perioperative diagnosis. CONCLUSION: The 3-D imaging may result in a more realistic view, reducing the frequency of classifying Sanders III fractures than with the 2-D CT imaging series. 3-D imaging may be more reliable than CT in the planning of operative treatment of displaced intra-articular calcaneal fractures. LEVEL OF EVIDENCE: Level III.

Intra- and inter-observer reliability of measurements on 3D images of the calcaneus bone.

BACKGROUND: The use of the 3D orientation angle of the calcaneal posterior subtalar (PTC) joint facet might be superior to the Böhler's angle to evaluate the quality of reduction after performing an open reduction and internal fixation (ORIF) of displaced intra-articular calcaneal fractures (DIACFs). Methods: Three-Dimensional segmentations of the preoperative, postoperative and uninjured calcaneus of 54 patients with a DIACF were assessed by 4 observers with different medical backgrounds. After the delineating of the PTC on the 3D images, a MeVisLab™ software calculated the 3D orientation angle of the PTC, which was determined as the average of the angles between the normal vectors of the PTC and the main axis of the calcaneus, calculated by principal component analysis. The intraclass correlation coefficient (ICC) was used to determine the intra- and inter-observer reliability. Results: The ICC of the intra-observer measurements varied from 0.699 to 0.890. For the preoperative measurements an inter-observer ICC of 0.828 was calculated. For the postoperative measurements the calculated inter-observer ICC amounted 0.692. The inter-observer ICC of the uninjured measurements amounted 0.776. Discussion: Observation of the PTC on 3D images of the calcaneus shows a good intra- and inter-observer reliability, which means it is safe to use the 3D OAC of the PTC in clinical practice.

Identification of Postoperative Step-Offs and Gaps With Brodén's View Following Open Reduction and Internal Fixation of Calcaneal Fractures.

BACKGROUND: To date, there is no consensus regarding which postoperative imaging technique should be used after open reduction and internal fixation of an intra-articular calcaneal fracture. The aim of this study was to clarify whether Brodén's view is sufficient as postoperative radiologic examination to assess step-offs and gaps of the posterior facet. METHODS: Six observers estimated the size of step-offs and gaps on Brodén's view in 42 surgically treated intra-articular calcaneal fractures. These findings were compared to postoperative CT scans (gold standard). Inter- and intraobserver reliability were calculated and compared using intraclass correlation coefficients (ICCs). RESULTS: An accuracy of approximately 75% for both step-offs and gaps was found in foot and ankle experts. Less experienced observers correctly identified step-offs and gaps in approximately 62% of cases on fluoroscopy and in 48% on radiographs. Interobserver reliability for intraoperative fluoroscopy as well as postoperative radiographs was fair for step-offs, whereas interobserver reliability for gaps was excellent. Intraobserver reliability showed a low level of agreement for intraoperative fluoroscopy, in contrast to postoperative radiographs with excellent agreement for step-offs and good agreement for gaps. CONCLUSION: Our results show that especially for more experienced foot and ankle surgeons, in the majority of fractures, Brodén's view accurately showed step-offs and gaps following open reduction and internal fixation. Interobserver reliability showed a fair level of agreement for step-offs and excellent agreement for gaps. Intraobserver reliability was only enough for radiographs, not for fluoroscopy. LEVEL OF EVIDENCE: Level IV, case series.

The implementation of a clinical pathway enhancing early surgery for geriatric hip fractures: how to maintain a success story?

BACKGROUND: Timing of surgery in geriatric hip fracture treatment remains controversial. Early surgery is acknowledged as a quality indicator and NICE guidelines recommend surgery within 0-48 h from admission. In 2014 we implemented the indicator of early surgery in our institution, enhancing operative treatment within the next calendar day. We aimed to evaluate the implementation, define the room for improvement and provide strategies to maintain the quality indicator. METHODS: Clinical outcome of 744 patients (January 2011-December 2013) before early surgery was implemented, compared to 817 patients (June 2014-May 2017) after implementation of early surgery with a follow-up of 6 months. Data-analysis was done by Pearson's Chi-square test and Mann-Whitney U test. RESULTS: Early surgery was achieved in 47.6% and 85.7% in the preimplementation and postimplementation group, respectively (P < 0.001). Both 30 days and 6 months mortality were similar (6.0% vs. 5.4%, P = 0.573 and 18.7% vs. 16.9%, P = 0.355, preimplementation vs. postimplementation, respectively). Early surgery resulted in a significantly shorter total length-of-stay (14 vs. 12 days, P < 0.001, preimplementation vs. postimplementation, respectively). Early surgery did not reduce the readmission rate. CONCLUSIONS: The indicator of early surgery has been successfully implemented. Early surgery resulted in a significantly shorter LOS. No significant reduction in 30 days and 6 months mortality, and 90 days readmission was observed. To maintain early surgery, continuous engagement and monitoring is required by all shareholders involved and if necessary, adjustment of the clinical route is appropriate.

Is open acute Achilles tendon rupture repair still justified? A single center experience and critical appraisal of the literature.

INTRODUCTION: Acute Achilles tendon ruptures are injuries with multiple treatment strategies with possibly far reaching consequences. Open repair is associated with a high complication rate, whereas percutaneous techniques are associated with higher re-rupture rates. The goal of this study was to evaluate the clinical outcome and economic burden of open surgical repair and define a medically and economically sound treatment protocol for acute Achilles tendon ruptures. METHODS: Between June 2012 and December 2016 one hundred and five patients with an acute Achilles tendon rupture, treated in an open surgical manner, were studied retrospectively. All demographic, clinical and hospital-related costs were retrieved from the electronic patient database. ATRS questionnaires were sent to assess the functional outcome. A response rate of 70.5% was achieved. RESULTS: We recorded a complication rate of 40%, respectively sural nerve hypoesthesia (14.3%), delayed wound healing (28.6%), infection (20.9%) and re-rupture (4.8%). Surgical resident, as primary operating surgeon was associated with a higher complication rate (p = 0.042). Overall, a median functional ATRS score of 17 (IQR 6.5-39.5) was recorded. Infection was associated with significantly higher total healthcare costs per patient as compared to re-rupture (€17,435 vs. €4,537, p = 0.013). The total cost for surgical debridement (n = 6) was approximately 5-times higher than for re-rupture (n = 5), €108,382 vs. €22,272. The median ATRS score for surgical debridement after infection and re-rupture did not differ significantly from the overall ATRS score, respectively 32 (IQR 21-63) and 28 (IQR 15-28). Nevertheless, a difference of 10 points is considered clinically relevant. CONCLUSION: The overall functional outcome of open repair of Achilles tendon ruptures is rather good, however associated with a high complication rate, mainly due to wound problems and infection. Although several risk factors were identified, only the operating surgeon is modifiable. Considering the high total costs for surgical debridement in the context of infection compared to re-rupture surgery, despite equal functional outcome,we decided to change clinical practice to reduce the complication rate and healthcare costs. The outcome and precise costs for percutaneous repair will be addressed.

Are the current guidelines for surgical delay in hip fractures too rigid? A single center assessment of mortality and economics.

PURPOSE: Controversy remains around acceptable surgical delay of acute hip fractures with current guidelines ranging from 24 to 48 h. Increasing healthcare costs force us to consider the economic burden as well. We aimed to evaluate the adjusted effect of surgical delay for hip fracture surgery on early mortality, healthcare costs and readmission rate. We hypothesized that shorter delays resulted in lower early mortality and costs. METHODS: In this retrospective cohort study 2573 consecutive patients aged ≥50 years were included, who underwent surgery for acute hip fractures between 2009 and 2017. Main endpoints were thirty- and ninety-day mortality, total cost, and readmission rate. Multivariable regression included sex, age and ASA score as covariates. RESULTS: Thirty-day mortality was 5% (n = 133), ninety-day mortality 12% (n = 304). Average total cost was €11960, dominated by hospitalization (59%) and honoraria (23%). Per 24 h delay, the adjusted odds ratio was 1.07 (95% CI 0.98-1.18) for thirty-day mortality, 1.12 (95% CI 1.04-1.19) for ninety-day mortality, and 0.99 (95% CI = 0.88-1.12) for readmission. Per 24 h delay, costs increased with 7% (95% CI 6-8%). For mortality, delay was a weaker predictor than sex, age, and ASA score. For costs, delay was the strongest predictor. We did not find clear cut-points for surgical delay after which mortality or costs increased abruptly. CONCLUSIONS: Despite only modest associations with mortality, we observed a steady increase in healthcare costs when delaying surgery. Hence, a more pragmatic approach with surgery as soon as medically and organizationally possible seems justifiable over rigorous implementation of the current guidelines.

Improved Interobserver Reliability of the Sanders Classification in Calcaneal Fractures Using Segmented Three-Dimensional Prints.

We examined the added value of 3-dimensional (3D) prints in improving the interobserver reliability of the Sanders classification of displaced intraarticular calcaneal fractures. Twenty-four observers (radiologists, trainees, and foot surgeons) were asked to rate 2-dimensional (2D) computed tomography images and 3D prints of a series of 11 fractures, selected from cases treatment at our level I trauma center between 2014 and 2016. The interobserver reliability for the Sanders classification was assessed using kappa coefficients. Three versions of the Sanders classification were considered: Sanders classification with subclasses, Sanders classification without subclasses, and the combination of Sanders types III and IV because of the high incidence of comminution in both types. The reference standard for classification was the perioperative findings by a single surgeon. The 3D print always yielded higher values for agreement and chance-corrected agreement. The Brennan-Prediger-weighted kappa equaled 0.35 for the 2D views and 0.63 for the 3D prints for the Sanders classification with subclasses (p = .004), 0.55 (2D) and 0.76 (3D) for the classification without subclasses (p = .003), and 0.58 (2D) and 0.78 (3D) for the fusion of Sanders types III and IV (p = .027). Greater agreement was also found between the perioperative evaluation and the 3D prints (88% versus 65% for the 2D views; p < .0001). However, a greater percentage of Sanders type III-IV were classified with 2D than with 3D (56% versus 32%; p < .0001). The interobserver agreement for the evaluation of calcaneal fractures was improved with the use of 3D prints after "digital disarticulation."

Soft tissue complications and timing of surgery in patients with a tongue-type displaced intra-articular calcaneal fracture: An international retrospective cohort study.

INTRODUCTION: Tongue-type displaced intra-articular calcaneal fractures (DIACF) are associated with a specific pattern of fracture displacement in contrast to joint depression fractures. This may result in tension of soft tissue in the posterior part of the heel. Tension-induced ischemia can result in skin necrosis. The objectives of this study were to investigate whether patients with tongue-type calcaneal fractures exert a higher risk of complications, especially of the posterior soft tissues, than joint depression type fractures. Also, late interventions (e.g., antibiotics, debridements, and amputations) and the effect of timing of surgery on the complication rate was assessed. METHODS: In this international retrospective cohort study, data of adult patients with a DIACF in the period January 1, 2005-December 31, 2015 were extracted from patients' medical files. Descriptive, univariate, and multivariable analyses were performed in SPSS. RESULTS: A total of 560 patients with 632 DIACF were included (295 tongue-type and 337 non-tongue-type fractures). At hospital presentation, 20.3% of the patients with a tongue-type fracture had compromised posterior soft tissue versus 12.8% with non-tongue-type fractures (p = 0.032). However, corrected for potential confounders the risk was no longer statistically significant (OR 1.497; 95% CI 0.831-2.696). Patients with a TT-DIACF had a 1.2-3.4-fold higher rate of any local wound complication (deep infections, and full thickness lesions, p < 0.03). In addition they had 2.0-8.0-fold more intravenous antibiotics, debridements, soft tissue coverage procedures and amputations (p < 0.03). Patients who underwent surgery within two days after trauma had a higher risk to develop any complication, in particular superficial infections, when compared to surgery between 3-7 days, but no significant difference between 3 and 7 and ≥8 days could be demonstrated. CONCLUSION: Despite the fact that patients with a tongue-type fracture developed posterior skin and soft tissue compromise nearly twice as often, this difference disappeared after correction for confounders. The overall complication risk was increased in patients with tongue-type calcaneal fractures as compared to patients with a non-tongue-type fracture. Whether or not patients with tongue-type fractures require immediate surgery cannot be concluded from the data.

3D Printing Calcaneal Fractures: Continuously Improving our Care by Making a Complex Problem Tangible.

Calcaneal fractures are amongst the most complex injuries known to man. Their intricate anatomy and extensive damage after trauma make them difficult to understand and treat. Most surgeons specialized in foot and ankle trauma agree that in most patients surgical managements yields the best result. Functional outcome is largely dependent on preventing complications and restoring anatomy. Reconstruction of height and suntalar joint congruency for example are both associated with improved outcome. Over the years insight in the complex (patho-)anatomy has increased. First by conventional radiographs, later with computed tomography. Recently 3D scans and prints have been added to this armamentarium. The study in the current issue of the Journal of Investigative Surgery explores the use of 3D printed calcaneal fractures and the effect on restoring anatomy and functional outcome. An invited short commentary was provided.

The gracilis free muscle flap is more than just a "graceful" flap for lower-leg reconstruction.

In 60 consecutive cases, a gracilis free muscle flap was used to reconstruct defects in the lower extremity. Although the harvest of the gracilis free flap is straightforward, the flap is not frequently considered as a valid option for reconstruction because of its "gracile" shape. Hence, it is not considered voluminous enough to cover defects of significant size in the lower leg. However, once the epimysium is separated, the muscle flap spreads out and covers a large surface area, large enough to reconstruct wide rectangular wounds or extended spindleshaped defects. Especially in young patients, the volume of the gracilis muscle is much larger than expected from its descriptive but misleading name. Often it is precisely this patient population that gets involved in motorcycle accidents or traumas caused by contact sports. For the treatment of Gustilo type III open tibia fractures with moderately large-sized soft-tissue defects and for chronic lower leg defects with osteomyelitis, the gracilis muscle flap is an excellent choice. Fifty-nine out of the 60 flaps in long-term follow-up (minimally 3 years) fully healed. The pedicle can be more than 7 cm in length when the final dissection under the long adductor muscle is carried up to the origin at the deep femoral vessels. The functional and aesthetic outcomes at the donor site at the inner thigh are minimal, compared to alternative transfers for such defects, while the reconstructive features of the gracilis muscle flap are excellent.