Metatarsal Base Fractures Research Articles

Pediatric Foot: Development, Variants, and Related Pathology.

Pediatric foot development throughout childhood and adolescence can present a diagnostic dilemma for radiologists because imaging appearances may be confused with pathology. Understanding pediatric foot development and anatomical variants, such as accessory ossification centers, is essential to interpret musculoskeletal imaging in children correctly, particularly because many of these variants are incidental but others can be symptomatic. We first briefly review foot embryology. After describing common accessory ossification centers of the foot, we explain the different patterns of foot maturation with attention to irregular ossification and bone marrow development. Common pediatric foot variants and pathology are described, such as tarsal coalitions and fifth metatarsal base fractures. We also discuss pediatric foot alignment and various childhood foot alignment deformities.

Functional outcome and risk of non-union for 5th metatarsal base fractures.

Treatment of 5th metatarsal fractures via direct discharge from virtual fracture clinic (VFC) has become common practice in the NHS. We aim to assess the functional outcome and incidence of non-union in a series of 5th metatarsal base fractures, exposed to 1-year of follow-up. 194 patients who sustained a fracture between the period February 2019 to April 2020 were included, referred via the VFC pathway. Radiographs were reviewed to classify in which zone, the fracture occurred along with union on subsequent follow-up. Telephone follow-up was used to measure patient functional outcomes (EQ-5D & FAAM survey) and satisfaction with the VFC service. Off 194 patients, 53 (27.3%) had zone 1, 99 (51%) had zone 2, and 42 (21.6%) had zone 3 fractures. 80 were discharged directly from VFC, with 114 patients being offered at least one face to face clinic follow-up. Six (3.1%) patients had clinical and radiological evidence of non-union; 4 in zone 2, and 2 in zone 3. No zone 1 injuries were identified as a non-union. Only 2 patients had surgery, 1 of which was for symptomatic non-union. Of the 6 non-union patients, 1 had surgery, 4 did not wish to have surgery and the final non-union patient was deemed unsuitable for surgery. The VFC is an effective way of managing 5th metatarsal fractures, with high patient satisfaction. Conservative management has excellent outcomes, with a low percentage of zone 2 and 3 injuries developing a symptomatic non-union. Functional outcome surveys provide further reassurance.

Clinical and Radiographic Healing of Nonoperative and Operative Treatment of Jones Fractures.

Significant heterogeneity in the classification and treatment of zone 3 proximal fifth metatarsal base fractures ("true Jones fractures") exists. This study compared time to clinical and radiographic healing between patients treated operatively and nonoperatively. We hypothesized that patients treated nonoperatively may demonstrate a greater time to clinical healing. This was a retrospective cohort study of patients presenting to a large, urban, academic medical center with "Jones" fractures between December 2012 and April 2022. Jones fractures were defined as fifth metatarsal base fractures occurring in the proximal metadiaphyseal region, distal to the articulation of the fourth and fifth metatarsals on the oblique radiographic view. Clinical healing was the time point at which the patient had returned to their baseline ambulatory status with no tenderness to palpation. Radiographic healing was the presence of bridging callus across at least 3 cortices. A total of 2450 patients presented with fifth metatarsal fractures, and 166 fractures (6.8%) were true Jones fractures. Among patients with Jones fractures, 120 patients with 121 Jones fractures followed up at our institution and were included in the analysis (mean age 46.5 ± 18.5 years). Ninety-nine fractures (81.8%) were treated nonoperatively and 22 fractures (18.2%) operatively. There were no differences between nonoperative and operative groups in time to clinical healing (12.7 ± 7.1 vs 12.8 ± 4.8 weeks, P = .931) or radiographic healing (13.2 ± 8.1 vs 11.7 ± 5.9 weeks, P = .331). Overall healing rate was 96% for the nonoperative group compared with 96.2% for the operative group. In this study, nonoperative and operative treatment of true Jones fractures were associated with equivalent clinical and radiographic healing. The rate of delayed union in true Jones fractures was lower than previously described, and there was no difference in delayed union rate between nonoperative and operative management. Level III, retrospective cohort study.

Zone 2 Fifth Metatarsal Fractures Treated Nonoperatively Have Similar Time to Healing to Those Treated Operatively.

To quantify the rate of union and time to clinical and radiographic healing in Zone 2 proximal fifth metatarsal (MT) fractures and compare these outcomes between Zone 2 fractures treated operatively and nonoperatively. Retrospective cohort study. Academic Level I Trauma Center. Patients with fifth MT fractures who presented between December 2012 and April 2022 and confirmed to have Zone 2 fractures (defined as fractures entering the proximal 4-5 MT articulation on the oblique radiographic view) were included in the study analysis in either the operative or nonoperative cohort. Nonunion, time to clinical healing by, and time to radiographic healing between operative and nonoperative treatment. Among the 499 included patients, 475 patients (95.2%) were initially treated nonoperatively and 24 patients (4.8%) were treated operatively. Both groups were similar in demographics. There was no difference in the proportion of patients with nonunions between groups (6.1% in the nonoperative group vs. 3.8% in the operative group, P = 1.000). In addition, there was no statistically significant difference between groups with respect to the time to clinical healing (9.9 ± 8.3 weeks for the nonoperative group vs. 15.4 ± 15.0 weeks for the operative group, P = 0.117) or the time to radiographic healing (18.7 ± 12 weeks for the nonoperative group vs. 18.5 ± 16.6 weeks for the operative group, P = 0.970). Zone 2 fifth MT base fractures were successfully treated with nonoperative management. There was no evidence in this study that operative treatment leads to significantly faster clinical or radiographic healing. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Variations in the Management of Zone 2 5th Metatarsal Fractures Based on Physician Specialty

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: There is a wide variation in the management of acute “Zone 2” 5th metatarsal (MT) base fractures. The purpose of this study was to quantify these differences and evaluate the effect of treating physician specialty. Methods: This was a retrospective cohort study of patients with acute Zone 2 5th MT fractures who presented to a single large, urban, academic medical center between December 2012 and April 2022. Zone 2 was defined as the region of the 5th MT base bordered by the 4th and 5th MT articulation on the oblique radiographic view. Logistic regression was used to evaluate the odds of undergoing operative treatment based on provider specialty. Results: A total of 633 patients presented with Zone 2 fractures during the study period. 40.6% of patients initially presented to the ED, 36.3% to an urgent care (UC) center, and 23.1% directly to the office. Ultimately, 57.2% of patients were treated by orthopedic surgeons, 39.6% by podiatrists, and 3.2% by primary care physicians. For patients treated nonoperatively, the management plan significantly differed by treating specialty. Compared to podiatrists, patients treated by orthopedic surgeons were more likely to be treated in a hard sole shoe (30.8% versus 7.6%, p< 0.001) and less likely to be treated using a CAM boot (57.3% versus 76.3%, p< 0.001). Similarly, patients treated by orthopedic surgeons were more likely to be made WBAT compared to patients treated by podiatrists (71.8% versus 42.0%, p< 0.001). Conclusion: Overall, 2.5% of patients with Zone 2 metatarsal fractures were treated operatively. 0.5% of patients treated by orthopedic surgeons underwent surgery compared to 6.1% of patients treated by podiatrists (p=0.001). Furthermore, when controlling for age, sex, and time between injury and initial presentation to the office, the likelihood of undergoing operative treatment was still significantly greater when being treated by a podiatrist (OR=16.5, p=0.009). There is considerable heterogeneity among the treatment strategies for Zone 2 proximal 5th MT fractures. Compared to podiatrists, orthopedic surgeons are less likely to treat patients operatively and more likely to allow early weight bearing.

Operative Treatment of Jones Fractures (OTA Type 87,5.2A) is not Associated with Earlier Clinical or Radiographic Healing

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: The purpose of this study was to compare the time to radiographic and clinical healing between patients with metadiaphyseal metatarsal fractures (True Jones) treated operatively and those treated nonoperatively. Methods: This was a retrospective cohort study of patients presenting to a single large, urban, academic hospital center with Jones fractures between December 2012 and April 2022. Jones fractures were defined as 5th metatarsal base fractures occurring in the proximal metadiaphyseal region, just distal to the articulation of the 4th and 5th metatarsals on the oblique radiographic view (Zone 3). Information regarding patient demographics, injury mechanism, clinical presentation, management, and time to healing was collected. A fracture was defined as clinically healed when the patient had returned to their baseline ambulatory status without pain and there was an absence of tenderness to palpation on physical examination. Radiographic healing was defined as the presence of complete osseous consolidation. A total of 2,466 patients presented with 5th metatarsal fractures during the study period. Results: Among all 5th metatarsal fractures, 170 patients (6.9%) were classified as “true Jones” fractures. The mean age of patients presenting with Jones fractures was 46.1 +/- 18.6 years, and 65.8% were female. 19.9% were treated operatively (92.9% with screw fixation and 7.1% with ORIF), and 80.1% were treated nonoperatively. 95.9% of patients with Jones fractures went on to heal with no difference in time to radiographic healing (p = 0.296) or clinical healing between both groups (p = 0.228). Furthermore, there was no difference between groups with respect to the proportion of patients who developed delayed radiographic union with incomplete osseous healing at 6 months post-injury (9.3% in the nonoperative group versus 10.7% in the operative group, p = 0.098). Conclusion: Contrary to popular opinion, operative treatment of true Jones fractures was not associated with faster or more reliable radiographic union or time to clinical healing compared to patients treated nonoperatively. The overall rate of nonunion in true Jones fractures was found to be lower than previously described, and there was no evidence of any difference in nonunion rate with operative treatment compared to nonoperative management.

Normal Variation of the Lisfranc Joint: Tridimensional Analysis using Weight-Bearing Computed Tomography Imaging

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: Untreated Lisfranc injuries can lead to chronic pain, midfoot arthritis, and functional disability 1,2,5. Approximately 20% of Lisfranc injuries are misdiagnosed or completely missed on initial evaluation, which can be attributed to a lack of parameters of what is within normal limits for subjects without injury in the Lisfranc complex3,4. The purpose of this study is to identify anatomic variations of unidimensional, bidimensional, and tridimensional (1D, 2D, 3D) measurements of the Lisfranc complex of normal individuals using weight-bearing computed tomography (WBCT) imaging. Our hypothesis is that there is some variation among individuals with a difference between right and left of the same individual of less than 10%. Methods: A total of 191 subjects with bilateral WBCT scans of the foot were collected from three tertiary medical centers from 2019-2022. Exclusion criteria included: history of Lisfranc injury, first to fourth metatarsal base fractures, Charcot arthropathy, midfoot arthritis, cuneiform fractures, and forefoot surgery proximal to the metatarsal neck region. The following Lisfranc joint measurements were collected6 bilaterally: joint volume (3D), area of the joint on a consistent axial slice (2D), and distance between the second metatarsal and medial cuneiform (1D). Foot alignment was assessed using lateral talar-first metatarsal angle (Meary’s Angle). Patient demographics (age, sex, weight, height, BMI) were also collected. Descriptive statistics were calculated for quantitative variables. Percent difference was used to assess volume, area, and distance variation between sides.7 Correlation between demographic data and Lisfranc measurements was assessed using Pearson Correlation tests. A T-test was used for categorical variables. A p-value < 0.05 was considered statistically significant. Results: The cohort included 61% female and 39% male with an average age of 45.2±17.3 years. The mean volume, area, and distance measurements of the Lisfranc joint for both left and right sides are shown in Figure 1. Overall, the mean percent difference between left and right sides were 11.9%, 14.9% and 13.9% for volume, area and diastasis, respectively (Figure 1). No association was found between age, BMI, or weight and the volume, area or distance measurements. A correlation (r=0.48, p= < 0.001) was found between height and left Lisfranc joint volume, but no other measurements. Significant difference between sex in volume (p < 0.001) and area (p < 0.001) measurements were found. Foot alignment did not have a correlation with a variation of the Lisfranc complex measurements. Conclusion: This study provides an objective characterizing of the anatomic variations of the Lisfranc joint amongst healthy individuals. Differences in the measurements and the large standard deviation in absolute measurements of volume, area, and distance suggests that percent difference with the contralateral side may be a better metric to use to diagnose Lisfranc instability. Our results showed that the difference between bilateral sides in a patient is less than 15% for volume, area, and diastasis. The results of this study can set the foundation for future studies to determine the cut-off value for the diagnosis of Lisfranc instability using WBCT imaging.

The Accuracy of 3D Measurements in Weightbearing Computed Tomography to Diagnose Lisfranc Instability

Category: Midfoot/Forefoot; Other Introduction/Purpose: Up to one-third of Lisfranc injuries are missed on initial evaluation, resulting in significant morbidity. Prompt diagnosis of Lisfranc injuries is, therefore, critical in optimizing outcomes, and yet there remains a lack of consensus on diagnostic criteria to identify Lisfranc instability using anatomic measurements. Prior studies have underscored the utility of weight-bearing computed tomography (WBCT) in diagnosing Lisfranc instability, which allows for bilateral three-dimensional (3D) evaluation under physiologic load. The aim of this study was to quantify appropriate cutoff values using 3D anatomic measurements of Lisfranc instability under physiologic load and as compared to the uninjured extremity. Methods: A total of 234 adult patients with bilateral WBCT scans of the foot were included: 43 patients with Lisfranc instability & 191 patients without a history of midfoot injuries. Lisfranc instability was confirmed intraoperatively or by clinical evaluation by the surgeon. Patients with prior midfoot surgery, Charcot arthropathy, severe midfoot arthropathy, or significantly displaced fracture of the cuneiforms or 1st, 2nd, or 3rd metatarsal bases were excluded. Lisfranc joint measurements were conducted bilaterally, including C1-M2 diastasis, C1-M2 area and 3D WBCT volume. Patient demographics were collected. Descriptive statistics were calculated for quantitative variables. Percent difference as compared to the contralateral side was calculated for volume, area, and diastasis. Mann Whitney U tests were utilized to determine differences in measurements between patients in the Lisfranc cohort and patients in the uninjured cohort (p-value < 0.05). Diagnostic cutoffs for Lisfranc instability were determined with minimum distance to the corner analysis on ROC curves. Results: The distribution of patients with Lisfranc instability was 58% female with an average age of 38.5±17.6 years. Of the Lisfranc injuries, 36% were purely ligamentous, 18% demonstrated an avulsion injury, and 43% involved a metatarsal base fracture. In the Lisfranc cohort, the median percent difference between injured and uninjured feet was 28.2% (IQR: 20.9%) for volume, 36.3% (IQR: 31.1%) for C1-M2 area, and 40.0% (IQR: 23.3%) for C1-M2 diastasis. Mann-Whitney testing was significant for percent difference between left and right feet for Lisfranc patients versus patients with an uninjured midfoot (p < 0.001). The area under the curve and associated diagnostic cutoffs for Lisfranc instability, were 0.81 and 18% for volume, 0.84 and 20% for area, and 0.91 and 28% for diastasis (Figure 1). Conclusion: Diastasis (1D), area (2D), and volume (3D) measurements are effective measurements to diagnose Lisfranc instability on WBCT. With current diagnostic algorithms, however, 1D measurements afford superior diagnostic sensitivity as compared to 2D and 3D measurements when using WBCT, suggesting Lisfranc instability may be best appreciated in the axial plane. Additional studies are necessary to expand the sample population to assess for corroboration with the current results, especially for subtle Lisfranc instability.

Zone 2 5th Metatarsal Fractures Treated Nonoperatively Have Similar Time to Healing to Those Treated Operatively

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: The purpose of this study was to quantify the time to clinical and radiographic healing in Zone 2 proximal 5th metatarsal (MT) fractures and to compare these outcomes to those of Zone 2 fractures treated operatively. Methods: A retrospective cohort study of all Zone 2 metatarsal fractures seen at a single large, urban, academic medical center between December 2012 and April 2022 was performed. Zone 2 injuries were defined as fractures entering the proximal 4-5 MT articulation on the oblique radiographic view. Clinical healing was characterized by the return to baseline ambulatory function without discomfort and a lack of tenderness on physical examination. Radiographic healing was defined as complete osseous consolidation. A total of 374 patients with Zone 2 proximal 5th MT fractures were included in the analysis. The mean age of patients was 53.8 +/- 16.6 years, and 74.3% were female. Results: 93.3% of patients with Zone 2 metatarsal fractures were treated nonoperatively. In the nonoperative group, 6.6% experienced delayed bony union with incomplete radiographic healing after 6 months, compared to 16.0% of the operative group (p = 0.095). However, by 1 year post-injury, 98.9% of patients who underwent nonoperative management and 96.0% of operative patients demonstrated radiographic union. Two patients failed nonoperative management and underwent operative fixation for symptomatic nonunions. There was no difference in time to radiographic healing between patients treated nonoperatively and those treated operatively (4.4 +/- 2.8 months vs 5.4 +/- 4.7 months, p = 0.413). Similarly, there was no difference in time to clinical healing between both groups (2.3 +/- 1.9 months vs 2.6 +/- 3.8 months, p = 0.723). Conclusion: Zone 2 5th metatarsal base fractures, which are often incorrectly referred to as Jones fractures despite being proximal to the fractures originally characterized by Jones, can be successfully treated with nonoperative management. There is no evidence that operative treatment leads to significantly faster clinical or radiographic healing for patients.

Short term clinical and patient reported outcomes following Virtual Fracture Clinic management of fifth metatarsal fractures

IntroductionFracture clinics are experiencing increased referrals and decreased capacity. Virtual fracture clinics (VFC) are an efficient, safe, and cost-effective solution for specified injury presentations. There is currently a lack of evidence to support the use of a VFC model in the management of 5th metatarsal base fractures. This study aims to assess clinical outcomes and patient satisfaction with the management of 5th metatarsal base fractures in VFC. We hypothesise that it is both safe and cost effectiveness. MethodsPatients presenting to VFC at our major trauma centre with a 5th metatarsal base fracture, between January 2019 and December 2019, were included. Patient demographics, clinic appointments, complication and operative rates were analysed. Patients received standardised VFC treatment; walker boot/full weight bearing, rehabilitation information and instructions to contact VFC if symptoms of pain persist after 4 months. Minimum follow-up was one year; Manchester-Oxford Foot Questionnaires (MOXFQ) were distributed. A basic cost analysis was performed. Results126 patients met inclusion criteria. Mean age was 41.6 years (18–92). Average time from ED attendance to VFC review was 2 days (1 – 5). Fractures were classified according to the Lawrence and Botte Classification with 104 (82%) zone 1 fractures, 15 (12%) zone 2 fractures and 7 (6%) zone 3 fractures. At VFC, 125/126 were discharged. 12 patients (9.5%) arranged further follow-up after initial discharge; pain the reason in all cases. There was 1 non-union during the study period. Average MOXFQ score post 1 year was 0.4/64, with only 11 patients scoring more than 0. In total, 248 face-to-face clinic visits were saved. ConclusionOur experience demonstrates that the management of 5th metatarsal base fractures in the VFC setting, with a well-defined protocol, can prove safe, efficient, cost effective and yield good short term clinical outcomes.

Determining the Key Predictive Factors for Non-Union in Fifth Metatarsal Fractures: A Machine Learning-Based Study

Category: Midfoot/Forefoot; Trauma; Other Introduction/Purpose: Metatarsal fractures account for over 35% of all foot fractures, and of these 68% specifically involve the fifth metatarsal [1],[2]. Subgroups of fractures affecting the fifth metatarsal base may be at higher risk of nonunion and therefore benefit from early surgical fixation, but traditional predictive models focus on the location of the fracture and little else. In this study, we aimed to determine predictive factors associated with non-union of fifth metatarsal fractures to assist surgeons and patients, alike, in identifying those at higher risk of nonunion. Methods: A retrospective machine learning-based analysis of 1,000 patients, >=18 y/o, diagnosed with a fifth metatarsal fracture at three tertiary medical centers was conducted. The fifth metatarsal base fracture was confirmed radiographically. We gathered imaging and narrative data including demographics (age, height, weight, BMI, gender, race, smoking habits, activity level), medications, chronic conditions, and fracture status (fracture zone, displacement, treatment method, healing status, and healing time). Non-union was described as failing to heal within 180 days of initial injury [3]. A machine learning analysis together with Pearson's correlation test and T-test were utilized where applicable. Five imputation methods were used to fill in missing datapoints. P<0.05 was considered statistically significant. Results: Overall, this cohort of patients demonstrated a non-union rate of 22.4%. When divided by fracture zone, Zone 2 fractures results in a statistically significant increased rate of delayed union (17.2%) and non-union (8.6%), when compared to Zone 1 (10.8% and 5.8%, respectively) and Zone 3 (9.7%, 2.3%). Analysis of correlation between demographics data and union rates found no correlation with age, gender, race, or BMI. Our machine learning algorithm outcomes showed a significant correlation between nonunion and seven chronic diseases: diabetes, thyroid disease, hypertension, gastroesophageal reflux disease (GERD), irritable bowel syndrome (IBS) obstructive sleep apnea (OSA), and glaucoma. In terms of medications, significant correlation with nonunion was demonstrated with the use of levothyroxine, lisinopril, aspirin, steroids, and acetaminophen. Conclusion: Zone 2 fifth metatarsal base fractures have a significantly higher rate of nonunion as compared to other zones. Comorbid conditions including diabetes, thyroid disease, OSA, and glaucoma as well as medications, may also play a role, though their mechanism or correlative precipitants are yet to be determined. Although our results demonstrated correlation, causality can only be assessed using studies with limited confounding factors, such as clinical trials. Our outcomes suggest that physicians should pay attention not only to the location of the fracture, but also past medical history and medication use when making treatment decisions and discussing prognosis with patients.

Resection of a Symptomatic Os Vesalianum with Peroneus Brevis Reattachment: A Report of 3 Cases and Literature Review of 100 Years

Category: Midfoot/Forefoot; Sports Introduction/Purpose: Os vesalianum is a very rare accessory foot bone located adjacent to the fifth metatarsal base. The estimated prevalence is below 1 %. In most cases it remains asymptomatic and is diagnosed as an incidental radiographic finding. Rarely the os vesalianum causes pain in the lateral midfoot. Therefore, only a few case reports about a symptomatic os vesalianum were published in the past. Here, we present what we believe to be the first small case series on that subject together with a review of the literature. Methods: Over a course of 10 years, we have treated three female patients (aged 18-36 years) who presented with pain on exercise in their lateral midfoot over the fifth metatarsal base. All of them had been diagnosed having a nonunion of the fifth metatarsal base, two after having sustained a direct or indirect trauma to the foot. The diagnosis of an accessory bone (os vesalianum) adjacent to the fifth metatarsal base fracture and with a joint facet to the cuboid bone could be made in retrospect in all cases by critically evaluating the initial radiographs. Technetium bone scans revealed an isolated increased uptake at the fifth metatarsal base. Upon surgical exploration, an irritation of the lateral facet of the cuboid with focal cartilage lesion through the accessory bone was noted in all 3 cases as a potential source of pain. Results: In all three cases, resection of the symptomatic os vesalianum and reinsertion of the peroneus brevis tendon into the fifth metatarsal base with a suture anchor was performed an led to a complete relief of pain within 3 months. At a minimum of 12 months follow-up all three patients fully returned to all previous activities including sports. The foot function index (FFI-D) improved from an average of 25.7 to an average of 3.67 at follow-up. One patient had a prominent subcutaneous suture knot removed, otherwise no complications were seen and no revision surgeries were needed in the further course. A systematic review of the literature revealed just 20 reported cases of a symptomatic os versalianum over 100 years (between 1922 and 2021). Previous treatment included observation, rest, resection with or without tendon reattachment, internal fixation and bone grafting. Conclusion: The knowledge of the location and morphology of accessory bones is indispensable when searching for rare causes of chronic foot pain. An os vesalianum may become symptomatic after direct and indirect trauma. The differential diagnosis must include an acute fifth metatarsal base fracture, non-union, or apophysitis (Iselin's disease), a distal peroneus brevis tendon lesion and lateral plantar fasciopathy. Resection of a symptomatic os vesalianum with reattachment of the peroneus brevis tendon to the 5th metatarsal base leads to a foot that is pain free and fully functional in most reported cases including the present series.

Reliability of Fifth Metatarsal Base Fracture Classifications and Current Management.

Classification of fifth metatarsal base fractures has been a source of confusion since originally described by Jones in 1902. Zone classifications have been described but never evaluated for reliability. The most recent classification, metaphyseal vs meta-diaphyseal, may be unknown to many surgeons. The purpose of this study was to evaluate reliability of American Orthopaedic Foot & Ankle Society (AOFAS) members classifying fifth metatarsal base fractures and current management of these fractures. A survey was emailed to AOFAS members including radiographs of 18 fifth metatarsal base fractures. Demographic information was collected in addition to evaluation of the radiographs. Interrater reliability was assessed for each measurement: presence of Jones fracture, zone classification, and metaphyseal vs metaphyseal-diaphyseal, using Fleiss kappa. After 3 weeks, a second email was sent to the members asking to retake the survey to evaluate intrarater reliability. Respondents were asked which region is a Jones fracture, which classification is used, if symptomatic zone 2 and 3 fractures are treated similarly, and what fractures are operative in healthy symptomatic acute fractures. A total of 223 AOFAS members, with a median time in practice of 12 years (range 0-50), completed the initial survey. Eighty members (36%) repeated the survey for intrarater comparison. Interrater reliability was moderate for Jones and zone classification but substantial for the 2-zone metaphyseal/meta-diaphyseal classification. The median intrarater kappa was 0.78, 0.75, and 0.78 for Jones, zone, and metaphyseal/meta-diaphyseal respectively. Seventy percent of respondents treat zones 2 and 3 similarly, and approximately 60% consider an acute symptomatic fracture identified as Jones, zone 2 or zone 3 operative. A 2-zone system may be the best available classification for fifth metatarsal base fractures given high interrater reliability and 70% of AOFAS members treat zones 2 and 3 in similar fashion. Level III, diagnostic study.

CORR Insights®: What Is the Interrater and Intrarater Reliability of the Lawrence and Botte Classification System of Fifth Metatarsal Base Fractures?

1Professor, Department of Orthopaedics, Case Western Reserve University, Cleveland, OH, USA R. E. Marcus ✉, Department of Orthopaedics, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH 44106, USA, Email: [email protected] This CORR Insights® is a commentary on the article “What Is the Interrater and Intrarater Reliability of the Lawrence and Botte Classification System of Fifth Metatarsal Base Fractures?” by Noori and colleagues available at: DOI: 10.1097/CORR.0000000000002131. The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writer, and do not reflect the opinion or policy of CORR® or The Association of Bone and Joint Surgeons®.

What Is the Interrater and Intrarater Reliability of the Lawrence and Botte Classification System of Fifth Metatarsal Base Fractures?

Fractures of the proximal fifth metatarsal are common, and often they are classified using a three-part scale first proposed by Lawrence and Botte. A clear consensus on prognosis and treatment for these fractures is lacking, particularly for fractures in the middle classification, Zone 2; the reliability of the classification scheme itself may be partly at fault for this. The intra- and interrater reliability of the classification itself has never been established, and it remains unclear whether the three-part classification of fifth metatarsal fractures can be applied consistently enough to guide treatment. When used by experienced orthopaedic surgeons, (1) What is the overall interrater reliability of the three-part Lawrence and Botte classification of fifth metatarsal base fractures? (2) What is the overall intrarater reliability of the three-part Lawrence and Botte classification of fifth metatarsal base fractures? (3) What are these same metrics for the individual transitions within the classification (Zone 1-2 and Zone 2-3)? Thirty sets of initial presentation radiographs representing an equal number of fractures originally diagnosed by treating clinicians as Zone 1, Zone 2, and Zone 3 were evaluated and classified by three orthopaedic surgeons specializing in foot and ankle surgery and eight foot and ankle fellows to determine interrater reliability. Two weeks later, the same set of radiographs were reevaluated in random order to determine intrarater reliability. Kappa values for interrater and intrarater reliability were calculated. Additionally, the individual transitions between zones were separately analyzed by calculating kappa values for a hypothetical two-part classification based on each transition. The three-part Lawrence and Botte classification of fifth metatarsal fractures demonstrated an overall interrater agreement of κ = 0.66 (observed agreement 77% versus chance agreement 33%). Intrarater reliability for the 11 surgeons ranged from κ = 0.60 to κ = 0.90. A two-part scheme divided by the transition between Zone 1 and Zone 2 demonstrated an interrater agreement of κ = 0.83, and a two-part scheme divided by the transition between Zone 2 and Zone 3 demonstrated a much lower interrater reliability of κ = 0.66. The three-part Lawrence and Botte classification system demonstrated a concerningly low level of interrater reliability with an observed agreement of 77% compared with a chance agreement of 33%. The primary source of concern is the assessment of the interface between Zone 2 and Zone 3, which proved much less reliable than that between Zone 1 and Zone 2. This suggests that previous studies of isolated Zone 1 fractures likely contain a homogeneous fracture cohort, whereas studies of Zone 2 or Zone 3 fractures are likely to include a mixture of fracture types. In practice, the consensus treatment of fifth metatarsal fractures differs based on whether they represent a more proximal, avulsive injury or a more distal injury from indirect trauma. Our data suggest that the Lawrence and Botte classification should be abandoned. Further work should focus on developing a new classification scheme that demonstrates improved interobserver reliability and more directly corresponds to this treatment paradigm. Level III, diagnostic study.

Therapy strategies of fifth metatarsal base fracture with lateral collateral ligament injury

BackgroundFifth metatarsal base fracture (fifth MBF) and lateral collateral ankle ligament (LCAL) injury are mainly caused by plantar flexion and inversion of the foot. However, there is no relevant report on the incidence, injury type and treatment principle of the fifth MBF combined with an LCAL injury.Materials and methodsWe retrospectively analyzed 61 patients with fifth MBF. After admission, patients were given the symptomatic treatment and underwent standard anteroposterior (AP), 30-degree oblique foot radiographs, ankle MR and/or ultrasonic examination. The type of surgery varied base on the individual patients (type of fracture with/without lateral collateral ankle ligament injury).ResultsIn 61 patients, there were 39 patients with LCAL injury. Among the 39 patients with LCAL injury, 24 patients with Grade I–II injury, 6 patients with Grade III injury, and 9 patients with avulsion fractures. There was no significant difference between the patients without LCAL injury and the patients with LCAL injury in terms of age (p = 0.67) and gender (p = 0.575). The incidence of fifth MBF with LCAL injury accounted for 63.93% of fifth metatarsal base fracture; the most common causes of injury included sprains and falls. The average fracture healing time was 8.3 (range, 6–12) weeks. For fifth MBF with displaced more than 2 mm, hook plate or lag screw was used for fixation; for complete rupture of LCAL, suture anchor was used to repairing the ligament; for partial LCAL injury, plaster was used for fixation after surgery; for avulsion fractures, cannulated screw or suture anchor was used for repair. None of the patients had complications such as delayed union, nonunion, and incision infection.ConclusionEarly diagnosis and appropriate treatment can obtain good therapeutic results in fifth MBF patients combined with LCAL injury. Moreover, defining a treatment plan for ligament injury is essential for reducing postoperative complications. This study provides a basis for epidemiology, diagnosis, and treatment of fifth MBF with LCAL injury.

Inter-Rater Reliability of Classifications for Fifth Metatarsal Base Fractures

Category:Trauma; Midfoot/Forefoot; SportsIntroduction/Purpose:Fractures of the fifth metatarsal base have been a source of confusion since their original description by Jones in 1902. The term Jones' fracture has been used indiscriminately leading to further confusion. Zone classifications have been described but never evaluated for their reliability. The most recent classification, metaphyseal versus metaphyseal-diaphyseal is unknown to most surgeons. The purpose of this study was to evaluate the inter-rater reliability of American Orthopaedic Foot & Ankle Society (AOFAS) members classifying fractures of the base of the fifth metatarsal.Methods:A survey was emailed to members of the AOFAS including radiographs of 18 fifth metatarsal base fractures. Demographic information was collected in addition to evaluation of the 18 sets of radiographs using three classification systems. Surgeons were asked if the fracture is a Jones' fracture, zone of the fracture and if the fracture was metaphyseal or metaphyseal- diaphyseal. A total of 223 surgeons with an average experience of 14 years in practice (range: fellow - 50 years) completed the initial survey for inter-rater reliability. Additionally, each surgeon was asked which zones or zone junctions they consider a Jones' fracture. Reliability was tested using Fleiss' Kappa scores.Results:Inter-rater agreement for use of the term Jones' fracture was moderate (kappa 0.533, 95% confidence interval (CI) [0.530, 0.535]). The zone classification had an inter-rater agreement was moderate (kappa 0.537, 95% CI [0.535, 0.539]). Inter- rater agreement for metaphyseal versus metaphyseal-diaphyseal was substantial (kappa 0.705, 95% CI [0.702, 0.708]). Results of surgeon definition of a Jones' fracture is seen in Figure 1.Conclusion:This is the largest study of its kind looking at inter-rater reliability of an orthopaedic classification with 223 raters. The terminology regarding the classification of fifth metatarsal base fractures remains confusing and inconsistent. The term Jones' fracture has little meaning in terms of communicating these injuries as there is only moderate agreement when surveying surgeons and it is defined differently by most. The zone classification has similar reliability as the Jones' fracture. The terms metaphyseal and metaphyseal-diaphyseal was the most reliable means to describe these fractures.

Inter-Rater and Intra-Rater Reliability of the Lawrence and Botte Classification System of Fifth Metatarsal Base Fractures

Category:Trauma; Midfoot/ForefootIntroduction/Purpose:Fractures of the proximal fifth metatarsal are common injuries with a unique history. Treatment of these fractures is controversial, in part due to confusion regarding the nomenclature of the fracture subtypes. The most commonly utilized classification system is the Lawrence and Botte classification, which separates fractures into zones 1, 2, and 3 based on their relationship to the tuberosity and the 4th-5th intermetatarsal articulation. The purpose of this study was to evaluate the inter-rater and intra-rater reliability of the Lawrence and Botte classification of fifth metatarsal base fractures.Methods:Thirty sets of x-rays representing an equal number of zone 1, zone 2 and zone 3 fractures of varying chronicity were sent to eleven fellowship trained orthopedic foot and ankle surgeons. Surgeons were asked to classify each fracture according to the Lawrence and Botte classification system (round 1). No review of the classification system or visual aids were provided. Two weeks later, the same set of x-rays were reordered and renumbered in a random fashion. The surgeons then re-classified each fracture in a blinded fashion under the same conditions (round 2). Inter-rater and intra-rater reliability was summarized using the kappa statistic. To determine the source of variability between the zones, additional analyses were performed to determine the kappa statistic for a) combined zone 1 and 2 fractures versus zone 3 fractures and b) combined zone 2 and 3 fractures versus zone 1 fractures.Results:The Lawrence and Botte classification demonstrated substantial overall inter-rater agreement for both rounds 1 and 2 (kappa = 0.66 and 0.65, respectively). Zone 1 fractures demonstrated the highest inter-rater reliability (kappa = 0.83 and 0.83). There was moderate agreement for zone 2 fractures (kappa = 0.51 and 0.50). There was substantial agreement for zone 3 fractures (kappa = 0.64 and 0.65). Dichotomous evaluation of the zone 1 vs. combined zones 2-3 boundary yielded excellent agreement (kappa = 0.83, 0.83). The combined zones 1-2 vs. zone 3 boundary yielded a much lower agreement (kappa = 0.66, 0.65). Intra-rater reliability varied by individual, with kappa values ranging from 0.60 to 0.90, corresponding to modest to almost perfect agreement.Conclusion:The Lawrence and Botte classification system has overall substantial inter-rater and intra-rater reliability, but assessment of the interface between zone 2 and zone 3 fractures is much less reliable than that between zone 1 and zone 2. Previous studies of isolated zone 1 fractures most likely contain a homogenous fracture cohort, while studies of zone 2 or zone 3 fractures are likely to include a mixture of fracture types. Future studies may utilize supplemental imaging or modify the classification to best determine treatment of these more distal fractures.

Outcomes and Cost Analysis of Virtual Fracture Clinic Management of 5th Metatarsal Base Fractures

Category:Midfoot/Forefoot; TraumaIntroduction/Purpose:Overwhelming demand for trauma services with increasing emergency department (ED) attendances, has increased pressure on fracture clinics in many units, with this demand exceeding capacity. Virtual fracture clinics (VFCs) have been shown to be safe and cost-effective in many specialties. Optimal treatment of 5th metatarsal base fractures remains controversial. Complications of base of 5th metatarsal fractures include delayed union and painful mal/non-union. Surgical fixation has been shown to enable faster return to sport, with lower faster union times and lower non-union rates than conservative management. The aims of this study were to assess whether the management of 5th metatarsal base fractures using a VFC model is safe, cost-effective and accceptable to the patients, whilst avoiding undesirable outcomes.Methods:All patients presenting to the VFC at our major trauma centre, with a 5th metatarsal base fracture between January 2019 and December 2019 were included in the study. One hundred and thirty six patients were identified. All patients had a standardised VFC treatment protocol including full weight bearing in a walker boot, rehabilitation planning to wean out of the boot and advice to contact the unit for follow-up if ongoing pain after 4 months. Minimum follow-up was one year. Patient records were retrospectively reviewed for baseline demographic data, including co-morbidities and smoking history. Overall complication rates, including mal and non-union as well as operative intervention rates were noted. Patients from the cohort who required face to face appointments were identified and the cause for return was identified. A cost analysis was also performed to evaluate the financial implications of the service.Results:Mean age was 41,6 years (18-92). Average time from ED attendance to VFC review was 2 days (1 - 5). Fractures were classified according to the Torg Classification with 106 (78%) Type 1 fractures, 15 (11%) Type 2 fractures and 15 (11%) Type 3 fractures. At VFC, 135/136 (99.2%) were discharged with the appropriate 5th metatarsal base fracture protocol. Twelve patients (8.8%) arranged further follow-up after initial discharge. The most common reason for return was ongoing pain (6/8 - 75.0%). This subgroup of the patients required an average of 3 (1-6) further appointments. There was 1 non-union during the study period. Based on 2 face to face visits on a traditional pathway, 248 clinic visits were saved with an approximate cost saving of nearly £40,000 ($55,500).Conclusion:Our study supports the management of 5th metatarsal base fractures in the VFC setting. We have shown that the VFC model, with well a defined protocol is both safe and cost effective. Fifth metatarsal base fractures have good outcomes with conservative management, removing the traditional need to have in-person clinic visits to confirm the diagnosis, management and prognosis.

Association between Bone Mineral Density and Fracture Characteristics in the 5th Metatarsal Bone Base Fracture in Elderly for Prediction of Osteoporotic Fracture.

BackgroundThis study aimed to analyze the correlation between bone mineral density (BMD) and the type of 5th metatarsal fracture, as well as to demonstrate whether there is a difference in radiological findings (heel alignment angle [HAA], heel moment arm [HMA], and metatarsus angle) between fracture types.MethodsA total of 87 patients were enrolled in the study and allocated into 3 groups: the Zone 1 group (N=36), the Zone 2 group (N=33), and the Zone 3 group (N=18). The participants’ demographic data, T-scores, existing fracture or osteoporosis medications, and radiologic parameters including HAA, HMA, and metatarsus adductus angle were analyzed and compared.ResultsThere was a significant difference between the mean age of the participants, with the highest age in the Zone 1 group and the lowest in the Zone 3 group. Regarding the history of concurrent fracture or osteoporosis medications, there was no significant difference between the 3 groups. Similarly, no significant difference was observed between the 3 groups about the BMD values. In contrast, the HAA was statistically significant in all groups with a positive correlation of −8.9 in the Zone 1 group, a negative correlation of 3.55 in the Zone 2 group, and an inverse relationship of 6.1 in the Zone 3 group. The metatarsus adductus angle was significantly higher in the Zone 3 group than the Zone 1 and Zone 2 groups.ConclusionsThe location of a 5th metatarsal bone fracture is not significantly associated with BMD. However, mechanical influences, such as hindfoot varus or forefoot adductus, have a significant correlation with fracture types.