A morphological review of medial malleolar fractures - A large single centre series.

BACKGROUND: Many approaches to management of medial malleolar fractures are described in the literature however, their morphology is under investigated. The aim of this study was to analyse the morphology of medial malleolar fractures to identify any association with medial malleolar fracture non-union or malunion. METHODS: Patients who had undergone surgical fixation of their MMF were identified from 2012 to 2022, using electronic patient records. Retrospective analysis of their preoperative, intraoperative, and postoperative radiographs was performed to determine their morphology and prevalence of non-union and malunion. Lauge-Hansen classification was used to characterise ankle fracture morphology and Herscovici classification to characterise MMF morphology. RESULTS: A total of 650 patients were identified across a 10-year period which could be included in the study. The overall non-union rate for our cohort was 18.77% (122/650). The overall malunion rate was 6.92% (45/650). Herscovici type A fractures were significantly more frequently mal-reduced at time of surgery as compared to other fracture types (p = .003). Medial wall blowout combined with Hercovici type B fractures showed a significant increase in malunion rate. There is a higher rate of bone union in patients who had been anatomically reduced. CONCLUSION: The morphology of medial malleolar fractures does have an impact of the radiological outcome following surgical management. Medial wall blowout fractures were most prevalent in adduction-type injuries; however, it should not be ruled out in rotational injuries with medial wall blowouts combined with and Herscovici type B fractures showing a significant increase in malunions. Herscovici type A fractures had significantly higher malreductions. LEVEL OF EVIDENCE: Level 3 - Retrospective Cohort Study.

Effect of postoperative fracture gap on bone union: A retrospective cohort analysis of simple femoral shaft fractures.

BACKGROUND: Intramedullary nailing (IMN) is considered the gold-standard treatment for femoral shaft fractures. The post operative fracture gap is commonly recognized as a risk factor for nonunion. However, no evaluation standard for measuring the fracture gap size has yet been established. In addition, the clinical implications of the fracture gap size have also not been determined so far. This study aims to clarify how we should evaluate fracture gaps when assessing simple femoral shaft fractures with radiographs and to determine the acceptable cut-off value of the fracture gap size in simple femoral shaft fractures. METHOD: A retrospective observational study with a consecutive cohort was conducted at the trauma center of a university hospital. We investigated the fracture gap using postoperative radiography and the postoperative bone union of transverse and short oblique femoral shaft fractures fixed by IMN. The receiver operating characteristic curve analysis was conducted to obtain the fracture gap's mean, minimum, and maximum cut-off values. Fisher's exact test was used at the cut-off value of the most accurate parameter. RESULTS: In the four nonunions among the 30 cases, the analysis using ROC curves revealed that the maximum value had the highest accuracy among the maximum, minimum, and mean values of fracture-gap size. The cut-off value was determined to be 4.14 mm with high accuracy. Fisher's exact test showed that the incidence of nonunion was higher in the group with a maximum fracture gap of 4.14 mm or greater (risk ratio = not applicable, risk difference = 0.57, P = 0.001). CONCLUSION: In simple transverse and short oblique femoral shaft fractures fixed with IMN, the fracture gap on radiographs should be evaluated by the maximum gap in the AP and lateral views. The remaining maximum fracture gap of ≥4.14 mm would be a risk factor for nonunion.

Risk factors for pubic ramus fracture nonunion after conservative treatment of pelvic ring injuries: a retrospective cohort multicenter study.

PURPOSE: To determine the incidence of nonunion, clinical and radiological outcomes, and risk factors for nonunion in conservatively treated pubic ramus fractures among patients diagnosed with pelvic ring injury. METHODS: A total of 546 patients (192 men, 354 women) diagnosed with pubic ramus fracture, treated conservatively, and who had completed > 1 year follow-up at three level 1 trauma centers between January 2014 and December 2020, were enrolled. Clinical and radiological evaluations were compared between union and nonunion groups. Logistic regression and Kaplan-Meier analyses were used. RESULT: At the final follow-up, 527 (96.5%) and 19 (3.5%) patients had union and nonunion of fractures, respectively. The union and nonunion groups exhibited statistically significant differences in posterior injury (p = 0.040), bilateral ramus fracture (p < 0.001), initial displacement (p < 0.001), and clinical result (p < 0.001). In the multivariate logistic regression analysis, initial displacement (odds ratio, 4.727; p = 0.005) was analyzed as a risk factor for nonunion. According to the Kaplan-Meier analysis, the median initial displacement of nonunion occurrence was 17.9 mm (standard error, 1.211; 95% confidence interval 15.526-20.274), and nonunion patients were included if the displacement was > 15.9 mm (standard error, 1.305) on the 75th percentile. CONCLUSION: Conservative treatment is ineffective in some ramus fracture cases with pelvic ring injury. As ramus nonunion causes functional deterioration, active treatment is required if the displacement is ≥ 16 mm.

A review of scaphoid fracture, treatment outcomes, and consequences.

PURPOSE: Scaphoid fractures are the most common carpal fracture and can lead to severe complications like carpal collapse and osteoarthritis. This study reviewed scaphoid fracture patterns, outcomes, and consequences in conservative and surgical management. METHODS: Sixty-four patients with scaphoid fracture who attended the hand clinic at King Hussein Medical City from January 2022 to December 2022 were included and reviewed regarding the anatomical fracture site, the associated injury, the treatment modality (conservative versus surgical), the healing time, and fracture sequelae such as nonunion and scaphoid nonunion advanced collapse. RESULTS: Most patients were males (62 patients, 96.9%), and most (47, 73.4%) fell within 25 to 40 years. Scaphoid waist fracture was the most common location (40, 52.5%). Most patients (47, 73.4%) received conservative treatment and 17 (26.6%) were fixed acutely. However, nonunion complicated 53 fractures (82.8%). Notably, there were no differences in the union rate or time between cases of scaphoid nonunion treated with vascularized or nonvascularized grafts. Furthermore, there were no variations in union rates among genders, extremities, age, fracture locations, or among smokers. However, a higher union rate was noted in office workers and those who received conservative treatment. CONCLUSION: Nonunions were higher in our study than in the literature, as our department is a referral center for established nonunion cases. For conservative treatment, we recommend aggressive management and follow-up with a clinical and CT scan at three months and early referral of non-united fractures to the hand clinic to avoid the advanced collapse of the scaphoid.

Odontoid fracture type and angulation affect nonunion risk, but comminution and displacement do not: A propensity score matched analysis of fracture morphology.

OBJECTIVE: Odontoid fractures disproportionately affect older patients who have high surgical risk, but also high rates of fracture nonunion. To guide surgical decision-making, we quantified the effect of fracture morphology on nonunion among nonoperatively managed, traumatic, isolated odontoid fractures. METHODS: We examined all patients with isolated odontoid fractures treated nonoperatively at our institution between 2010 and 2019. Multivariable regression and propensity score matching were used to quantify the effect of fracture type, angulation, comminution, and displacement on bony healing by 26 weeks from injury. RESULTS: 303 consecutive traumatic odontoid fracture patients were identified, of whom 163 (53.8 %) had isolated fractures that were managed nonoperatively. Selection for nonoperative management was more likely with older age (OR=1.31 [1.09, 1.58], p = 0.004), and less likely with higher fracture angle (OR=0.70 [0.55, 0.89], p = 0.004), or higher presenting Nurick scores (OR=0.77 [0.62, 0.94], p = 0.011). Factors associated with nonunion at 26 weeks were fracture angle (OR=5.11 [1.43, 18.26], p = 0.012) and Anderson-D'Alonzo Type II morphology (OR=5.79 [1.88, 17.83], p = 0.002). Propensity score matching to assess the effect of type II fracture, fracture angulation> 10o, displacement≥ 3 mm, and comminution all yielded balanced models (Rubin's B<25.0, 0.5  10o (p = 0.015), and there was an 18.2 % lower rate of bony healing for each 10o increase in fracture angle. Fracture displacement≥ 3 mm and comminution had no significant effect. CONCLUSION: Type II fracture morphology and fracture angle > 10o significantly increase nonunion among nonoperatively managed isolated traumatic odontoid fractures, but fracture comminution and displacement ≥ 3 mm do not.

"Fragment Width Ratio" as a Predictor of Nonunion for Femoral Shaft Fracture With Third Fragments.

Previous studies have reported that large fracture fragment with displacement might cause nonunion of femoral shaft fractures. We therefore intended to delineate significant risk factors for developing a nonunion predisposed by a major fracture fragment. We analyzed 61 patients who were operated on using interlocking nails for femoral shaft fractures from 2009 to 2018. We classified patients with modified Radiographic Union Scale for Tibia fractures scores of less than 11 or needing reoperations by 1 year postoperatively as nonunion. We thereafter measured parameters of the displaced fracture fragment and fracture site to identify the significant difference between the union and non-union groups. We also applied the receiver operating characteristic curve to demonstrate a threshold value for the fragment width (FW) ratio. Among 61 patients with complete follow-up, no significant difference was found regarding length, displacement, and angulation of fragments between patients with and without union. Except for higher mean FW (P=.03) and the FW ratio (P=.01) in patients with nonunion, the logistic regression analysis demonstrated that FW ratio significantly affected union (P=.018; odds ratio, 0.21; 95% CI, 0.001-0.522). Although a fracture fragment greater than 4 cm with displacement greater than 2 cm was reported to significantly cause nonunions, our study showed that an FW ratio greater than 0.55 instead of fragment size or displacement was predictive for the occurrence of nonunion adjoining to the fracture site. Fixation of the third fracture fragment should not be ignored for preventing a nonunion. More attention should be paid to achieve a better fixation for a major fracture fragment with an FW ratio greater than 0.55 to avoid the development of non-union following the use of interlocking nail for femoral shaft fracture. [Orthopedics. 2023;46(3):169-174.].

Nonunion of conservatively treated humeral shaft fractures is not associated with anatomic location and fracture pattern.

INTRODUCTION: Humeral shaft fractures make up 1-3% of all fractures and are most often treated nonoperatively; rates of union have been suggested to be greater than 85%. It has been postulated that proximal third fractures are more susceptible to nonunion development; however, current evidence is conflicting and presented in small cohorts. It is our hypothesis that anatomic site of fracture and fracture pattern are not associated with development of nonunion. MATERIALS AND METHODS: In a retrospective cohort study, 147 consecutive patients treated nonoperatively for a humeral shaft fracture were assessed for development of nonunion during their treatment course. Their charts were reviewed for demographic and radiographic parameters such as age, sex, current tobacco use, diabetic comorbidity, fracture location, fracture pattern, AO/OTA classification, and need for intervention for nonunion. RESULTS: One hundred and forty-seven patients with 147 nonoperatively treated humeral shaft fractures were eligible for this study and included: 39 distal, 65 middle, and 43 proximal third fractures. One hundred and twenty-six patients healed their fractures by a mean 16 ± 6.4 weeks. Of the 21 patients who developed a nonunion, two were of the distal third, 10 of the middle third, and nine were of the proximal third. In a binomial logistic regression analysis, there were no differences in age, sex, tobacco use, diabetic comorbidity, fracture pattern, anatomic location, and OTA fracture classification between patients in the union and nonunion cohorts. CONCLUSIONS: Fracture pattern and anatomic location of nonoperatively treated humeral shaft fractures were not related to development of fracture nonunion.

Serology and Comorbidities in Patients With Fracture Nonunion: A Multicenter Evaluation of 640 Patients.

INTRODUCTION: This multicenter cohort study investigated the association of serology and comorbid conditions with septic and aseptic nonunion. METHODS: From January 1, 2011, to December 31, 2017, consecutive individuals surgically treated for nonunion were identified from seven centers. Nonunion-type, comorbid conditions and serology were assessed. RESULTS: A total of 640 individuals were included. 57% were male with a mean age of 49 years. Nonunion sites included tibia (35.2%), femur (25.6%), humerus (20.3%), and other less frequent bones (18.9%). The type of nonunion included septic (17.7%) and aseptic (82.3%). Within aseptic, nonvascular (86.5%) and vascular (13.5%) nonunion were seen. Rates of smoking, alcohol abuse, and diabetes mellitus were higher in our nonunion cohort compared with population norms. Coronary artery disease and tobacco use were associated with septic nonunion (P < 0.05). Diphosphonates were associated with vascular nonunion (P < 0.05). Serologically, increased erythrocyte sedimentation rate, C-reactive protein, parathyroid hormone, red cell distribution width, mean platelet volume (MPV), and platelets and decreased absolute lymphocyte count, hemoglobin, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and albumin were associated with septic nonunion while lower calcium was associated with nonvascular nonunion (P < 0.05). The presence of four or more of increased erythrocyte sedimentation rate, C-reactive protein, or red cell distribution width; decreased albumin; and age younger than 65 years carried an 89% positive predictive value for infection. Hypovitaminosis D was seen less frequently than reported in the general population, whereas anemia was more common. However, aside from hematologic and inflammatory indices, no other serology was abnormal more than 25% of the time. DISCUSSION: Abnormal serology and comorbid conditions, including smoking, alcohol abuse, and diabetes mellitus, are seen in nonunion; however, serologic abnormalities may be less common than previously thought. Septic nonunion is associated with inflammation, younger age, and malnourishment. Based on the observed frequency of abnormality, routine laboratory work is not recommended for nonunion assessment; however, specific focused serology may help determine the presence of septic nonunion.

Clinical and Epidemiological Features of Scaphoid Fracture Nonunion: A Hospital-Based Study in Beijing, China.

OBJECTIVE: Studies exploring the epidemiological characteristics of scaphoid fracture nonunion are important to understand the causes and lead to effective prevention strategy. However, such knowledge is limited especially in China. This study aims to reveal the clinical and epidemiological features of scaphoid fracture nonunion in Chinese patients. METHODS: This was a retrospective study, which was based on patients with scaphoid fracture nonunion treated in a Chinese national orthopedic referral center from 1 August 2009 to 1 August 2020. The basic demographic and clinical characteristics, including gender, age at diagnosis of scaphoid fracture nonunion, dominant hand, the location of fracture, the side, the causes of the injury, age of the injury, age of the treatment for scaphoid fracture nonunion, and the delay period, were retrieved from the medical records. The patients were divided into a non-delay group and a delay group based on whether they had visited the doctor within 1 month after the injury. Scaphoid fracture was classified into the proximal, waist, and distal fractures according to the location. The t-test or Mann-Whitney U test was used to compare the difference between groups when the dependent variable is continuous, while a chi-square test was used when the dependent variable is categorical. RESULTS: A total of 363 patients were included in this study. The mean age at the diagnosis of scaphoid fracture nonunion was 32 (ranging from 14 to 78). Waist fracture nonunion (76.5%) was most common. Among the 169 patients who sought medical care within 1 month after the injury (non-delay group), more than half (90 cases) were misdiagnosed. 23 cases could not recall the injury, so the time of delay could not be determined. Among the 171 patients who did not seek medical care for acute injury (delay group), the average time was 52 months between the initial injury and the treatment. The proportion of waist nonunions was higher among patients in the delay group than that in the non-delay group. CONCLUSIONS: Nonunion of scaphoid fracture is caused mainly by delayed treatment and misdiagnosis in China, suggesting that timely treatment and improved diagnosis could lower the prevalence. The fracture location may be a factor contributing to the delaying of seeking medical care.

The Prevalence of Metabolic and Endocrine Disturbances on Fracture Nonunion.

OBJECTIVE: This study aims to determine the prevalence of metabolic disturbance in all fracture nonunion cases and identify the most common endocrine abnormalities seen using a simple screening algorithm. METHODS: A retrospective review study was performed evaluating patients who underwent operative intervention for nonunion from January 2010 to December 2018 at 2 level-1 trauma centers. Preoperative laboratory values were recorded for a 9-test "nonunion panel." A metabolic or endocrine abnormality, specifically an abnormality in the thyroid or parathyroid axis, was evaluated. RESULTS: 42% of patients had an undiagnosed metabolic laboratory abnormality. When multiple tests were used, the rate of metabolic dysfunction was between 60% and 75%, depending on the definition of vitamin D insufficiency vs deficiency used. CONCLUSION: Results indicate a relatively high prevalence of metabolic disturbance in patients with nonunion and suggest metabolic screening for all nonunion patients not only those without a mechanical or infectious cause. LEVEL OF EVIDENCE: IV, retrospective case series.

Non-union bone fractures.

The human skeleton has remarkable regenerative properties, being one of the few structures in the body that can heal by recreating its normal cellular composition, orientation and mechanical strength. When the healing process of a fractured bone fails owing to inadequate immobilization, failed surgical intervention, insufficient biological response or infection, the outcome after a prolonged period of no healing is defined as non-union. Non-union represents a chronic medical condition not only affecting function but also potentially impacting the individual's psychosocial and economic well-being. This Primer provides the reader with an in-depth understanding of our contemporary knowledge regarding the important features to be considered when faced with non-union. The normal mechanisms involved in bone healing and the factors that disrupt the normal signalling mechanisms are addressed. Epidemiological considerations and advances in the diagnosis and surgical therapy of non-union are highlighted and the need for greater efforts in basic, translational and clinical research are identified.

Open Reduction and Internal Fixation for Humeral Shaft Nonunion: Bone Grafting Is Not Routinely Required and Avoids Donor Site Morbidity.

OBJECTIVES: To document union rate, complications and patient-reported outcomes after open reduction and internal fixation (ORIF), with and without bone grafting (BG), for humeral diaphyseal nonunion after failed nonoperative management. DESIGN: Retrospective. SETTING: University teaching hospital. PATIENTS AND INTERVENTION: From 2008 to 2017, 86 consecutive patients [mean age 59 years (range 17-86), 71% (n = 61/86) women] underwent nonunion ORIF (plate and screws) at a mean of 7 months postinjury (range 3-21.5). Eleven (13%) underwent supplementary BG. MAIN OUTCOME MEASUREMENTS: Union rate and complications for 83 patients (97%) at a mean of 10 months (3-61). Patient-reported outcomes (QuickDASH, EQ-5D, EQ-VAS, SF-12, satisfaction) for 53 living, cognitively-intact patients (78%) at a mean of 4.9 years (0.3-9.2). RESULTS: Ninety-three percent (n = 77/83) achieved union after nonunion ORIF. Complications included recalcitrant nonunion (7%, n = 6/83), iatrogenic radial nerve palsy (6%, n = 5/83), infection (superficial 7%, n = 6/83; deep 2%, n = 2/83), and iliac crest donor site morbidity (38%, n = 3/8). The union rate with BG was 78% (n = 7/9) and without was 95% (n = 70/74; P = 0.125), and was not associated with the nonunion type (atrophic 91%, n = 53/58; hypertrophic 96%, n = 24/25; P = 0.663). Median QuickDASH was 22.7 (0-95), EQ-5D 0.710 (-0.181-1), EQ-visual analog scale 80 (10-100), SF-12 physical component summary 41.9 (16-60.5), and mental component summary 52.6 (18.7-67.7). Nineteen percent (n = 10/53) were dissatisfied with their outcome. CONCLUSIONS: ORIF for humeral diaphyseal nonunion was associated with a high rate of union. Routine BG was not required and avoided the risk of donor site morbidity. One in 5 patients were dissatisfied despite the majority achieving union. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Impact of Treatment Delay on Malunion and Nonunion After Open Reduction of Mandible Fractures.

Importance: Time to surgical intervention is an oft-investigated potentially modifiable risk factor for complications after mandible fracture. Objective: To identify novel risk factors for malunion/nonunion after mandible fracture and determine the impact of treatment delay on malunion and nonunion after open reduction of mandible fractures. Design: Retrospective cohort. Setting and Participants: Encounter billing records from the New York State Inpatient Databases, State Emergency Department Databases, and State Ambulatory Surgery Databases. Patients aged 18 years and older with isolated mandible fracture in the emergency department or inpatient setting from January 1, 2006 to September 30, 2015. Main Outcomes and Measures: Mandibular Malunion/Nonunion. Results: A total of 19,152 adults were diagnosed with isolated mandible fracture. After fracture, 247 patients (1.3%) developed mandibular malunion or nonunion. In multivariable analysis, patients with open fractures (odds ratio [OR] 1.93, confidence interval [95% CI] 1.40-2.65), body fractures (OR 2.00, 1.50-2.65), alcohol abuse (OR 1.61, 1.22-2.11), diabetes mellitus (OR 1.57, 1.02-2.42), and Medicaid insurance (OR 1.46, 1.03-2.07) had increased risk, whereas patients with subcondylar fractures had reduced risk (OR 0.45, 0.28-0.72) of mandibular malunion/nonunion. The risk of mandibular malunion/nonunion after open reduction increased with treatment delay until 6-7 days after presentation (OR 1.84, 1.11-3.06). Conclusion and Relevance: Although treatment delay is often unavoidable, these findings suggest that physicians should consider early intervention in patients requiring open reduction of mandible fractures when able.

Do Nonsteroidal Anti-Inflammatory or COX-2 Inhibitor Drugs Increase the Nonunion or Delayed Union Rates After Fracture Surgery?: A Propensity-Score-Matched Study.

BACKGROUND: The effects of nonsteroidal anti-inflammatory drugs (NSAIDs)/cyclooxygenase (COX)-2 inhibitors on postoperative fracture-healing are controversial. Thus, we investigated the association between NSAID/COX-2 inhibitor administration and postoperative nonunion or delayed union of fractures. We aimed to determine the effects of NSAID/COX-2 inhibitor administration on postoperative fracture-healing with use of a common data model. METHODS: Patients who underwent operative treatment of a fracture between 1998 and 2018 were included. To determine the effects of NSAID/COX-2 inhibitor administration on fracture-healing, postoperative NSAID/COX-2 inhibitor users were compared and 1:1 matched to nonusers, with 3,264 patients matched. The effect of each agent on bone-healing was determined on the basis of the primary outcome (nonunion/delayed union), defined as having a diagnosis code for nonunion or delayed union ≥6 months after surgery. The secondary outcome was reoperation for nonunion/delayed union. To examine the effect of NSAIDs/COX-2 inhibitors on bone union according to medication duration, a Kaplan-Meier survival analysis was performed. RESULTS: Of the 8,693 patients who were included in the analysis, 208 had nonunion (178 patients; 2.05%) or delayed union (30 patients; 0.35%). Sixty-four (30.8%) of those 208 patients had a reoperation for nonunion or delayed union. NSAID users showed a significantly lower hazard of nonunion compared with the matched cohort of nonusers (hazard ratio, 0.69 [95% confidence interval, 0.48 to 0.98]; p = 0.040) but did not show a significant difference in the other matched comparison for any other outcomes. Kaplan-Meier survival analysis revealed significantly lower and higher nonunion/delayed union rates when the medication durations were ≤3 and >3 weeks, respectively (p = 0.001). For COX-2 inhibitors, the survival curve according to the medication duration showed no significant difference among the groups (p = 0.9). CONCLUSIONS: Our study demonstrated no short-term impact of NSAIDs/COX-2 inhibitors on long-bone fracture-healing. However, continued use of these medications for a period of >3 weeks may be associated with higher rates of nonunion or delayed union. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Prediction of Nonunion After Nonoperative Treatment of a Proximal Humeral Fracture.

BACKGROUND: The prevalence of nonunion after a proximal humeral fracture (PHF) and the risk factors for its occurrence are poorly defined. We aimed to estimate the rate of nonunion in nonoperatively treated patients and to produce a clinical model for its prediction. METHODS: Two thousand two hundred and thirty adult patients (median age, 72 years [range, 18 to 103 years]; 75.5% were female) with a PHF underwent assessment of fracture union using standard clinical evaluation and conventional radiographs. We assessed the prevalence of nonunion and measured the effect of 19 parameters on healing. Best statistical practices were used to construct a multivariate logistic regression model. The PHF assessment of risk of nonunion model (PHARON) was externally validated in a subsequent prospectively collected population of 735 patients, treated by the same protocol in our institution. RESULTS: Overall, 231 (10.4%) of 2,230 patients developed nonunion. Only 3 (0.8%) of 395 patients with a head-shaft angle (HSA) of >140° developed nonunion; in this cohort, none of the measured candidate variables were independently predictive of nonunion on multivariate logistic regression analysis. In the larger cohort of 1,835 patients with an HSA of ≤140°, 228 (12.4%) developed nonunion. Decreasing HSA, increasing head-shaft translation (HST), and smoking were independently predictive of nonunion on multivariate analysis. The prevalence of nonunion was very low (1%) in the majority with both an HSA of >90° and HST of <50%, whereas the risk was much higher (83.7%) in the 8.3% with an HSA of ≤90° and HST of ≥50%. In both groups, the prevalence of nonunion was much higher in smokers. CONCLUSIONS: The prevalence of nonunion after PHF is higher than previously reported. Most patients have favorable risk-factor estimates and a very low risk of this complication, but a smaller subgroup is at much higher risk. The risk can be accurately estimated with PHARON, using standard clinical assessment tools. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The risk assessment model of fracture nonunion after intramedullary nailing for subtrochanteric femur fracture.

ABSTRACT: To investigate the influencing factors of fracture nonunion after intramedullary nailing for subtrochanteric fractures and to construct a risk assessment model.Based on the multicenter retrospective analysis of 251 patients, all patients were divided into modeling group and verification group. In the modeling group, postoperative fracture nonunion rate, general data, fracture-related factors, surgical reduction-related factors, mechanical and biological factors were calculated, and the influencing factors of fracture nonunion were screened by univariate analysis. Logistic regression model was used for multifactor analysis to construct the risk assessment model. Based on the logistic regression model, the risk prediction model was constructed by drawing the Nomogram diagram. Through the verification group, the influencing factors were evaluated again, and the differentiation and calibration of the model were evaluated. The calibration degree was evaluated by Hosmer-Lemeshow test, goodness of fit test, and calibration curve. The discriminant degree was evaluated by the receiver operating characteristic curve.Fracture nonunion occurred in 34 of 149 patients in the modeling group. Among the 14 potential influencing factors, univariate analysis and logistic regression analysis showed that postoperative hip varus, intramedullary nail fixation failure, and reduction of fracture with large incision were the risk factors of fracture nonunion. The medial cortex fracture was seen reduced on X-Ray was a protective factor for fracture nonunion, and a regression equation was established. Based on the logistic regression model, the Nomogram diagram is drawn. Twenty-four cases of fracture nonunion occurred in the verification group. The area under the receiver operating characteristic curve was area under curve =0.883 > 0.7, indicating that there was a moderate differentiation to evaluate the occurrence of fracture nonunion after operation. The goodness of fit test: the Hosmers-Lemeshow test (X2 = 2.921, P = .712 > .05) showed that the model had a good calibration.After intramedullary nailing of subtrochanteric fracture, hip varus, failure of intramedullary nail fixation and wide surgical dissection are the risk factors of fracture nonunion, and the postoperative reduction of medial cortex fracture is protective factor.National key research and development projects: 2016YFC0105806.

Breaking Barriers: Studying Fracture Healing in the BONES Program.

SUMMARY: The Bioventus Observational Noninterventional EXOGEN Studies (BONES) Program includes 3 concurrent studies designed to estimate the incidence of fracture nonunions in patients treated with the EXOGEN Ultrasound Bone Healing System compared with those receiving standard fracture care. This article outlines the design and methodology within the fifth metatarsal fracture study; similar approaches are taken in the second and third BONES Program studies, which examine nonunions of the tibia and scaphoid. The BONES Program is an external comparator design and incorporates several unique, fit-for-purpose components to strengthen the approach and allow it to be submitted to the US Food and Drug Administration (FDA) to be considered for a label expansion. BONES consisted of 2 cohorts: (1) EXOGEN-treated patients recruited into a patient registry and (2) comparator patients from a large administrative health claims database. The study used International Classification of Diseases, Tenth Revision, nonunion diagnosis codes reported by the treating clinician for the primary outcome measure. Many data sources (medical and billing records, patient-reported health data, usage data from the device itself, and commercial product complaint system) were used on the registry side, alongside insurance claims data to source the external comparator cohort, to achieve broader understanding of factors predisposing patients to the development of nonunions. In step with the FDA's increasing acceptance of real-world evidence for use in regulatory decision making and coupled with the infeasibility of a randomized clinical trial in this setting, the innovative study design of the BONES Program allowed for both an evaluation of the effect of EXOGEN in mitigating nonunions in a real-world setting and an assessment of the patient experience with EXOGEN treatment.

Risk Analysis of Nonunion After First Metatarsophalangeal Joint Arthrodesis.

Objective: The standard therapy for a symptomatic hallux rigidus is still the arthrodesis of the first metatarsophalangeal (MTP) joint. A nonunion of the arthrodesis is a possible postoperative complication. This study aimed to evaluate the incidence of nonunion associated with first MTP joint arthrodesis and identify risk factors influencing this. Methods: This retrospective study included 197 patients who were treated with an isolated first MTP joint arthrodesis. The severity of MTP-related osteoarthritis was assessed clinically and radiologically prior to surgery according to the Waizy classification. Patient characteristics and radiological parameters were evaluated postoperatively. Results: A full clinical and radiological data set was collected from 153 out of 197 patients. We identified 14 cases of nonunion and found that nonunion was associated with higher incidence of male gender (P = .29), comorbidity (P = .035), higher grade of osteoarthritis (P = .01), and increased postoperative great toe dorsiflexion (P = .022). Conclusions: Arthrodesis of the first MTP joint is a safe operative treatment, as demonstrated by a nonunion rate of 9.2%. Negative influencing factors were the presence of preexisting diseases, higher grades of osteoarthritis, and a relative increased dorsiflexion position of the great toe after surgery. These factors should be considered during pre-, intra-, and postoperative planning.Levels of Evidence: Therapeutic, Level IV: Retrospective.

The Rates of Nonunion and Malunion in Lower Extremity Fractures: Experience in South Carolina over 17 years.

Our purpose was to determine the rates of lower extremity nonunion and malunion over 17 years in South Carolina. Our hypothesis was that malunions and nonunions decreased over time due to improved access to trauma centers and improved orthopaedic surgical training. The South Carolina Department of Budget and Control Hospital Discharge Database was queried between 1998-2014 and yielded a total of 4,994 malunions and 16,454 nonunions. Malunions increased from 1.2% (1998) to 1.8% (2010); nonunions increased from 4.0% (1999) to 5.8% (2011). Older age and gender were predictive of malunion and nonunion. This study identified females as having a higher odds ratio for malunion or nonunion; higher nonunion rates in worker's compensation or government payer status; and older age as incurring greater risks for sustaining fractures or developing a malunion or nonunion. There was increased prevalence of nonunion and malunion despite improved access to trauma centers and trained orthopaedic trauma surgeons. (Journal of Surgical Orthopaedic Advances 29(3):129-134, 2020).