Technical improvements in preparing 3D printed anatomical models for comminuted fracture preoperative planning.

Preoperative planning of comminuted fracture repair using 3D printed anatomical models is enabling surgeons to visualize and simulate the fracture reduction processes before surgery. However, the preparation of such models can be challenging due to the complexity of certain fractures, particularly in preserving fine detail in bone fragments, maintaining the positioning of displaced fragments, and accurate positioning of multiple bones. This study described several key technical considerations for preparing 3D printed anatomical models for comminuted fracture preoperative planning. An optimized segmentation protocol was developed that preserves fine detail in bone fragments, resulting in a more accurate representation of the fracture. Additionally, struts were manually added to the digital model to maintain the positioning of displaced fragments after fabrication, reducing the likelihood of errors during printing or misrepresentation of fragment positioning. Magnets were also used to enable separation and visualization of accurate positioning of multiple bones, making it easier to visualize fracture components otherwise obscured by the anatomy. Finally, the infill for non-target structures was adjusted to minimize print time and material wastage. These technical optimizations improved the accuracy and efficiency of preparing 3D printed anatomical models for comminuted fracture preoperative planning, improving opportunities for surgeons to better plan surgical treatment in advance, reducing the likelihood of errors, with the goal of improving surgical outcomes.

A deep surgical site infection risk score for patients with open tibial shaft fractures treated with intramedullary nail.

OBJECTIVES: To identify deep infection risk factors in patients with open tibial shaft fractures and to develop a scoring algorithm to predict the baseline deep infection risk in this patient population. METHODS: A retrospective cohort study conducted at a single academic trauma center identified patients with open tibial shaft fractures treated with intramedullary nail fixation from December 2006 to October 2020. The primary outcome was a deep surgical site infection requiring surgical debridement. The outcome was identified by Current Procedural Terminology codes and confirmed with a medical chart review documenting evidence of a tibial draining wound or sinus tract. RESULTS: Deep surgical site infection occurred in 13% of patients (97/769). Factors that predicted deep surgical site infection were identified. Gustilo-Anderson type IIIB or IIIC was the strongest predictor with a 12-fold increase in the odds of deep infection (OR 11.8, p < 0.001). Additional factors included age >40 years (OR 1.7, p = 0.03), American Society of Anesthesiologists score ≥3 (OR 1.9, p < 0.01), Gustilo-Anderson type IIIA vs. type I or II (OR 2.8, p = 0.004), and gunshot wounds (OR 2.9, p = 0.02). The risk scoring model predicted patients who would develop an infection with an acceptable level of accuracy (AUC 0.79). The risk score categorized patients from a low probability of deep infection 2%-6% with <10 points to high risk (58%-69%) with >40 points. CONCLUSIONS: This risk score model predicts deep postoperative infection in patients with open tibial shaft fractures treated with intramedullary nails. The ability to accurately estimate deep infection risk at the time of presentation might aid patient expectation management and allow clinicians to focus infection prevention strategies on the high-risk subset of this population.

Is the timing of fixation associated with fracture-related infection among tibial plateau fracture patients with compartment syndrome? A multicenter retrospective cohort study of 729 patients.

BACKGROUND: Tibial plateau fractures with an ipsilateral compartment syndrome are a clinical challenge with limited guidance regarding the best time to perform open reduction and internal fixation (ORIF) relative to fasciotomy wound closure. This study aimed to determine if the risk of fracture-related infection (FRI) differs based on the timing of tibial plateau ORIF relative to closure of ipsilateral fasciotomy wounds. METHODS: A retrospective cohort study identified patients with tibial plateau fractures and an ipsilateral compartment syndrome treated with 4-compartment fasciotomy at 22 US trauma centers from 2009 to 2019. The primary outcome measure was FRI requiring operative debridement after ORIF. The ORIF timing relative to fasciotomy closure was categorized as ORIF before, at the same time as, or after fasciotomy closure. Bayesian hierarchical regression models with a neutral prior were used to determine the association between timing of ORIF and infection. The posterior probability of treatment benefit for ORIF was also determined for the three timings of ORIF relative to fasciotomy closure. RESULTS: Of the 729 patients who underwent ORIF of their tibial plateau fracture, 143 (19.6%) subsequently developed a FRI requiring operative treatment. Patients sustaining infections were: 21.0% of those with ORIF before (43 of 205), 15.9% at the same time as (37 of 232), and 21.6% after fasciotomy wound closure (63 of 292). ORIF at the same time as fasciotomy closure demonstrated a 91% probability of being superior to before closure (RR, 0.75; 95% CrI, 0.38 to 1.10). ORIF after fasciotomy closure had a lower likelihood (45%) of a superior outcome than before closure (RR, 1.02; 95% CrI; 0.64 to 1.39). CONCLUSION: Data from this multicenter cohort confirms previous reports of a high FRI risk in patients with a tibial plateau fracture and ipsilateral compartment syndrome. Our results suggest that ORIF at the time of fasciotomy closure has the highest probability of treatment benefit, but that infection was common with all three timings of ORIF in this difficult clinical situation.

Sensitivity and specificity of modified RUST score using clinical and radiographic findings as a gold standard.

AIMS: The modified Radiological Union Scale for Tibia (mRUST) fractures score was developed in order to assess progress to union and define a numerical assessment of fracture healing of metadiaphyseal fractures. This score has been shown to be valuable in predicting radiological union; however, there is no information on the sensitivity, specificity, and accuracy of this index for various cut-off scores. The aim of this study is to evaluate sensitivity, specificity, accuracy, and cut-off points of the mRUST score for the diagnosis of metadiaphyseal fractures healing. METHODS: A cohort of 146 distal femur fractures were retrospectively identified at our institution. After excluding AO/OTA type B fractures, nonunions, follow-up less than 12 weeks, and patients aged less than 16 years, 104 sets of radiographs were included for analysis. Anteroposterior and lateral femur radiographs at six weeks, 12 weeks, 24 weeks, and final follow-up were separately scored by three surgeons using the mRUST score. The sensitivity and specificity of mean mRUST score were calculated using clinical and further radiological findings as a gold standard for ultimate fracture healing. A receiver operating characteristic curve was also performed to determine the cut-off points at each time point. RESULTS: The mean mRUST score of ten at 24 weeks revealed a 91.9% sensitivity, 100% specificity, and 92.6% accuracy of predicting ultimate fracture healing. A cut-off point of 13 points revealed 41.9% sensitivity, 100% specificity, and 46.9% accuracy at the same time point. CONCLUSION: The mRUST score of ten points at 24 weeks can be used as a viable screening method with the highest sensitivity, specificity, and accuracy for healing of metadiaphyseal femur fractures. However, the cut-off point of 13 increases the specificity to 100%, but decreases sensitivity. Furthermore, the mRUST score should not be used at six weeks, as results show an inability to accurately predict eventual fracture healing at this time point. Cite this article: Bone Jt Open 2021;2(10):796-805.

Intraoperative Spinal Cord Monitoring Does Not Decrease New Postoperative Neurological Deficits in Patients With Cervical Radiculopathy or Spondylotic Myelopathy Undergoing One or Two Level Anterior Cervical Discectomy And Fusion.

BACKGROUND: Intraoperative neurological monitoring (IONM) is commonly used in spine surgery. However, the utility of IONM in anterior cervical decompression and fusion (ACDF) remains a topic of debate. The purpose of the study was to investigate the utility and cost of IONM (both Somatosensory evoked potentials (SSEPs) and Motor Evoked Potentials (Tc-MEPs)) in reducing postoperative neurological deficits in myelopathic and non-myelopathic patients undergoing ACDF. METHODS: Retrospective chart review was performed to include only patients with cervical radiculopathy or myelopathy undergoing one or two level ACDF over a 7-year period at a busy academic center. SSEP and Tc-MEP tracings were reviewed for all monitored patients and significant changes and inconsistencies were noted. IONM billing codes (SSEP/Tc-MEP) were reviewed and summed to evaluate the average procedural cost. Medical records were reviewed for preoperative physical exam and for new postoperative neurological deficits on postoperative day one and again at six weeks and matched to the monitored tracings. RESULTS: There were 249 total patients (48 Non-monitored, 201 monitored). There was no difference in gender, age, or BMI between monitored and non-monitored groups. There was no difference in new neurological deficits in monitored compared with non-monitored patients with radiculopathy (p=0.1935) or myelopathy (p=0.1977). However, when radiculopathy and myelopathy patients were combined, there was an increased incidence of new neurologic deficits in monitored patients (8.0%) versus non-monitored patients (0%) (p=0.0830). All new neurological deficits occurred in patients with normal IONM tracings. There were no new neurologic deficits in the non-monitored radiculopathy or myelopathy groups. The average IONM procedure charge was $6500. CONCLUSION: Our results indicate that intraoperative spinal cord monitoring did not reduce new neurological deficits in our cohort of patients. The higher incidence in new neurological deficits despite no IONM changes in our monitored group suggests a lack of utility of IONM in ACDF. Furthermore, at an average of $6500 per IONM procedure, the present study underlines the importance of prudence when choosing to use IONM in the era of cost containment.Level of Evidence: III.

Minimally Invasive Treatment of Displaced Intra-Articular Calcaneal Fractures.

Minimally invasive surgical techniques are increasingly used for definitive treatment of displaced intra-articular calcaneal fractures. These approaches have been shown to minimize soft tissue injury, preserve blood supply, and decrease operative time. These methods can be applied to all calcaneal fractures and have particular advantages in patients with higher than usual risks to the soft tissues. The literature suggests that results of limited soft tissue dissection approaches provide equivalent outcomes to those obtained with the extensile lateral approach. We predict that as imaging and other techniques continue to improve, more calcaneal fractures will be treated by these appealing safer techniques.

Use of Blood Flow Restriction Training for Postoperative Rehabilitation.

Blood flow restriction (BFR) training is commonly used to induce muscle hypertrophy and strength and is gaining popularity as a modality for treatment of musculoskeletal conditions and postoperative rehabilitation. This article reviews the current literature on BFR as a rehabilitative tool, identifies gaps in the literature, and reports the authors experience using BFR in the postoperative environment.

Radiographic Healing of Far Cortical Locking Constructs in Distal Femur Fractures: A Comparative Study With Standard Locking Plates.

OBJECTIVES: To investigate the radiographic healing of far cortical locking (FCL) construct fixation in distal femur fractures compared with traditional locking plate (LP) constructs. DESIGN: A retrospective cohort of 143 consecutive patients with 146 distal femur fractures. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: After excluding patients with OTA/AO type B fractures, referred nonunion cases, patients younger than 16 years, and patients with less than 24 weeks of follow-up, 69 patients with 70 total fractures were included for analysis. INTERVENTION: AP and lateral knee radiographs were blinded to type of screws and individually reviewed by 3 orthopaedic trauma surgeons. OUTCOME MEASUREMENTS: The modified RUST (mRUST) score was our primary outcome measure. mRUST scores were assigned at 6, 12, and 24 weeks and final follow-up based on AP and lateral radiographs and compared between FCL and LP groups as a tool for evaluating fracture healing. Secondary outcomes compared between FCL and LP included union rate and postoperative complications. RESULTS: Statistically significant differences in mRUST scores were noted between FCL and LP groups at 6 weeks (P = 0.040), 12 weeks (P = 0.034), 24 weeks (0.044), and final follow-up (P = 0.048). There was no significant difference in union or specific complication rates between the 2 groups. The union rate was 90.5% and 82.1% for the FCL and LP groups, respectively, at final follow-up. CONCLUSIONS: To our knowledge, this is the first comparative study between FCL and LP constructs. The FCL group was noted to have significantly higher mRUST scores at all periods indicating increased callus formation, but the differences seen were small and there were no differences in healing rates or complications between the 2 groups, thus bringing the clinical benefit of FCL into question. Further prospective study designs are needed to compare FCL with LP constructs and to investigate the role of interfragmentary motion on callus formation in distal femur fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Perioperative nutrition assessment in musculoskeletal trauma patients: Dietitian evaluation is superior to serum chemistries or modified screening questionnaire for risk stratification.

INTRODUCTION: Malnutrition is a potentially modifiable risk factor associated with increased hospital charges, major wound complication, and fracture non-union after orthopaedic surgery. The goal of this study was to examine the relationship between three nutrition screening tools and postoperative complications in patients undergoing acute fracture fixation. METHODS: Patients aged 18 or older undergoing acute operative fracture fixation at a Level I academic trauma center were screened upon admission using a malnutrition screening questionnaire (MSQ), and classified as low-, moderate- or high risk. Patients at moderate-to-high risk were assessed for clinical malnutrition by dietitian. Serum albumin, transferrin, total lymphocyte count, and 25(OH) Vitamin D were measured preoperatively. Primary outcome measures included twelve-month postoperative surgical and medical complications obtained by retrospective chart review. RESULTS: Of 373 patients, 17% were moderate-to-high risk of malnutrition by MSQ. Clinical malnutrition was diagnosed by dietitian in 4.3% of patients assessed. Nearly half of all subjects had deficiency in one or more serum biomarkers. Cost of biomarker assays was $624 per patient. Medical or surgical complications occurred in 19% of patients. Dietitian diagnosed malnutrition (clinical malnutrition) was the strongest predictor of complication (OR 3.49, p = 0.017). Hypoalbuminemia was also associated with increased complication risk (OR 1.79, p = 0.045). MSQ score was not correlated with postoperative complication. CONCLUSIONS: Among the examined malnutrition screening tools, clinical malnutrition had the strongest association with postoperative complication. Hypoalbuminemia was associated with increased odds of complication, however there was a large false positive rate with all tested serum chemistries and high associated hospital charges compared to dietitian assessment. MSQ was a poor predictor of malnutrition and clinical outcome. Dietetic assessment is advised for orthopaedic trauma patients.

Systemic Lupus Erythematosus is a Risk Factor for Complications in Total Joint Arthroplasty.

Introduction: Systemic Lupus Erythematosus (SLE) has been associated with increased complications following hip and knee arthroplasty. The Purpose of this study was to determine the extent to which SLE is a risk factor in outcomes following total joint arthroplasty (TJA). Methods: The nationwide inpatient sample was used to identify a cohort of 505,841 patients who had a total hip arthroplasty (THA) or total knee arthroplasty (TKA) between 2009-2011. Of these patients, 2,284 patients (0.45%) had been previously diagnosed with SLE. The impact of SLE on short-term TJA outcomes was determined using multivariate logistic regression. Differences in discharge destination and length of stay were also evaluated. Results: SLE patients were more likely to have an all-cause medical complication, (OR 1.9, p<0.0001) and more likely to have an all-cause surgical complication (OR 1.3, p<0.0001). SLE patients were four times more likely to become septic in the post-operative period (OR 3.8, p<0.0487). SLE patients were more likely to have a genitourinary complication (OR 1.7, p<0.0001) and bleeding complications requiring transfusion (OR 2.1, p<0.0001). Patients with SLE also had an increased length of stay (0.38 days, p<0.0001) and increased probability of discharging to a facility (OR 2.1, p<0.0001). Discussion: Patients with SLE had an increased rate of both medical and surgical all-cause complications. Patients were specifically found to be at higher risk for sepsis, genitourinary complications, and blood transfusions. Future risk adjustment models should include SLE as a contributor to medical and surgical complications in the postoperative period.

What Is the Impact of Smoking on Revision Total Knee Arthroplasty?

BACKGROUND: There is a paucity of literature evaluating the impact of smoking on revision arthroplasty procedures. The purpose of this study was to identify the effect of smoking on complications after revision total knee arthroplasty (rTKA). METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database to identify patients who underwent rTKA between 2006 and 2014. Patients were divided into current smokers and nonsmokers according to the NSQIP definitions. Each cohort was compared in terms of demographic data, preoperative comorbidities, and operative time. Infection end points were created from composite surgical site infection variables defined by the NSQIP database. Multivariate logistic regression analysis was utilized to adjust for confounding variables and calculate adjusted odds ratios (ORs) and associated 95% confidence intervals (95% CIs). RESULTS: In total, 8776 patients underwent rTKA. Of these patients, 11.6% were current smokers. Univariate analyses demonstrated that smokers had a higher rate of any wound complication (3.8% vs 1.8%, P < .0001), deep infection (2.5% vs 1.0%, P < .0001), pneumonia (1.3% vs 0.4%, P < .0001), and reoperation (5.0% vs 3.1%, P = .001) compared to nonsmokers undergoing revision total knee arthroplasty. Multivariate analysis identified current smokers as being at a significantly increased risk of any wound complication (OR 2.1; 95% CI 1.4-3.1) and deep infection (OR 2.1, 95% CI 1.2-3.6) after rTKA. CONCLUSION: This study demonstrates that smoking significantly increases the risk of infection, wound complications, and reoperation after rTKA. The results are even more magnified for revision procedures compared to published effects of smoking on primary total knee arthroplasty complications. Further research is needed regarding the impact of smoking cessation on mitigation of these observed risks.

The Functional and Structural Outcomes of Arthroscopic Iliopsoas Release.

BACKGROUND: Arthroscopic release of the iliopsoas tendon may alleviate pain associated with internal snapping hip, but previous reports of physical function, hip strength, and muscle atrophy after surgery are mixed. HYPOTHESIS: The hips of patients who underwent arthroscopic iliopsoas release would demonstrate significantly reduced hip flexion strength and iliopsoas muscle volume when compared with their contralateral hips and the hips of patients who underwent hip arthroscopy without psoas release. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Eighteen patients who underwent hip arthroscopy with iliopsoas release for symptomatic internal snapping hip and concomitant femoroacetabular impingement (FAI) and/or chondrolabral damage (release group) and 18 patients who underwent arthroscopy for FAI and/or chondrolabral damage without iliopsoas release (control group) were evaluated at a mean of 21 months (range, 16-30 months) postoperatively. Magnetic resonance images were performed and segmented to calculate iliopsoas volume. Isometric hip flexion strength was evaluated in the supine and seated positions with a custom testing apparatus. Differences between groups and differences between the operative and nonoperative limbs within groups were compared with unpaired and paired t tests, respectively. RESULTS: In the release group, the iliopsoas muscle of the surgical limb was significantly smaller (288 ± 98 vs 384 ± 113 cm(3), P < .001) and weaker in the seated position (13 ± 4.7 vs 17 ± 5.8 kg, P < .001) than the contralateral limb. Compared with the control group, the release group demonstrated a greater percentage decrease in iliopsoas volume on magnetic resonance imaging (-25% ± 9.1% vs -0.6% ± 4.6%, P < .001) and seated hip flexion strength (-19% ± 16% vs -3.9% ± 20%, P = .018) between the operative and contralateral limbs. There were no significant differences in supine strength between limbs or groups (all P > .168). CONCLUSION: Arthroscopic iliopsoas release results in iliopsoas atrophy with a 25% volume loss and a 19% reduction in seated hip flexion strength.