Special Considerations in Podiatric Science: Translational Research, Cadavers, Gait Analysis, Dermatology, and Databases

The objective of this article is to provide a brief overview of the critical analysis and design of unique and perhaps less common methodologies in podiatric science. These include basic science translational designs, cadaveric investigations, gait analyses, dermatologic studies, and database analysis. The relative advantages, disadvantages, and inherent limitations are reviewed with an intention to improve the interpretation of results and advance future foot and ankle scientific endeavors.

Basic Statistics, Statistical Design, and Critical Analysis of Statistics for Surgeons

Statistics is a set of tools used in medical decision-making no different than how a scalpel or a sagittal saw is used in the operating room. No foot and ankle surgeon is born with the inherent ability to perform, understand, and critically interpret them. Instead, it requires training and practice throughout the course of a career in medicine to develop a working proficiency. This article reviews the basic indications and interpretation of common descriptive and comparative statistical tests in the podiatric literature. Additionally, the concept of which tests are most appropriate for which investigational methodologies is introduced.

A Study Never Proves Anything: Contemporary Interpretation of the Levels of Clinical Evidence and Statistical Significance

Critical analysis of the medical literature and an evidence-based approach to clinical practice and medical decision-making is of vital importance in contemporary podiatric practice. This article reviews the levels of clinical evidence and their application within this paradigm. This includes determining which level of evidence is most appropriate for a given methodology, as well as an appreciation of inherent limitations within each level of evidence. The article concludes with a discussion on the difference between statistical significance and clinical significance.

Morbidity and Mortality of the Transmetatarsal Amputation: A Comparative NSQIP Analysis

The objective of this investigation was to compare the morbidity and mortality of transmetatarsal amputation to other frequently performed surgical procedures utilizing a large US database. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was interrogated for the purposes of this investigation. We initially extracted data related to the Current Procedural Terminology (CPT) code 28805 (amputation, foot; transmetatarsal) and the variable labels "estimated probability of morbidity" and "estimated probability of mortality." We subsequently performed a CPT code search for those procedures occurring at a frequency greater than 10,000 in the database, and additionally extracted data for estimated probability of morbidity and estimated probability of mortality for these procedures. This resulted in identification of 17 additional procedures. CPT code 28805 was associated with the highest estimated probability of morbidity of the cohort (0.1360 ± 0.0669), and this demonstrated statistical significance higher than all other CPT codes (p < .001). CPT code 28805 was associated with the second-highest estimated probability of mortality of the cohort (0.0327 ± 0.0596). This demonstrated statistical significance less than that of CPT code 27245 (0.0327 ± 0.0596 vs 0.0547 ± 0.0661; p < .0001), but statistical significance higher than all other CPT codes (p<0.001). The results of this investigation indicate that transmetatarsal amputation carries a substantial risk for morbidity and mortality in comparison to other commonly performed surgical procedures.

A Comparison of Adverse Short-Term Outcomes After Forefoot Amputation Based on Patient Height

BACKGROUND

The objective of this investigation was to evaluate adverse short-term outcomes after partial forefoot amputation with a specific comparison performed based on patient height.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was analyzed to select patients with a 28805 Current Procedural Terminology code (amputation, foot; transmetatarsal) who underwent the procedure with "all layers of incision (deep and superficial) fully closed." This resulted in 11 patients with a height of 60 inches or less, 202 with a height greater than 60 inches and less than 72 inches, and 55 with a height of 72 inches or greater.

RESULTS

Results of the primary outcome measures found no significant differences among groups with respect to the development of a superficial surgical site infection (0% versus 6.4% versus 5.5%; P = .669), deep incisional infection (9.1% versus 3.5% versus 10.9%; P = .076), or wound disruption (0% versus 5.4% versus 5.5%; P = .730). In addition, no significant differences were observed among groups with respect to unplanned reoperations (9.1% versus 16.8% versus 12.7%; P = .630) or unplanned hospital readmissions (45.5% versus 23.3% versus 20.0%; P = .190).

CONCLUSIONS

The results of this investigation demonstrate no differences in short-term adverse outcomes after partial forefoot amputation with primary closure based on patient height. Although height has previously been described as a potential risk factor in the development of lower-extremity pathogenesis, this finding was not observed in this study from a large US database.

Comparative Radiographic Analysis of the Width of the Lesser Digit Proximal Phalangeal Heads

BACKGROUND

Digital deformities represent a common presenting abnormality and target for surgical intervention in podiatric medicine and surgery. The objective of this investigation was to compare the radiographic width of the heads of the lesser digit proximal phalanges.

METHODS

One hundred fifty consecutive feet with a diagnosis of digital deformity and performance of weightbearing radiographs were analyzed. The maximum width of the heads of the lesser digit proximal phalanges were recorded from the radiographs using computerized digital software.

RESULTS

The mean ± standard deviation of the head of the second digit proximal phalanx was 9.74 ± 0.87 mm (range, 7.94-11.78 mm); the head of the third digit proximal phalanx, 9.00 ± 0.91 mm (range,7.27-10.94 mm); the head of the fourth digit proximal phalanx, 8.49 ± 1.01 mm (range, 5.57-10.73 mm); and the head of the fifth digit proximal phalanx, 8.67 ± 0.89 mm (range, 6.50-11.75 mm). The width of the head of the proximal phalanx decreased from the second digit to the third digit (P < .001), decreased from the third digit to the fourth digit (P < .001), and then increased from the fourth digit to the fifth digit (P = .032).

CONCLUSIONS

The results of this investigation provide evidence in support of an anatomical and structural contribution to digital deformities. The width of the heads of the lesser digit proximal phalanges decreased from the second to the third to the fourth toes, and then subsequently increased with the fifth proximal phalangeal head.

Minor and Major Amputation Rates Following Midfoot Charcot Reconstructive Surgery

Charcot neuroarthropathy (CNA) is a progressive disease that affects the bones and joints of the foot. To prevent collapse and loss of stability within the pedal architecture, CNA should be diagnosed and managed early. The objective of this retrospective study was to review patients who underwent midfoot CNA reconstructive surgery and evaluate subsequent rates of minor and major amputations. Secondary objectives include identifying patients that underwent midfoot CAN with and without a subtalar joint (STJ) arthrodesis. Out of the 72 patients, 4 (5.6%) underwent minor (digital, ray) amputation, 2 (2.8%) underwent proximal amputations (either below or above the knee), and none underwent midfoot amputation (transmetatarsal, Lisfranc, Chopart). A Fisher's exact test was employed to compare the outcomes of minor and major amputation rates in our CNA cohort with those who underwent midfoot CNA reconstruction with STJ arthrodesis and found no statistical significance (p = .15). Overall, a total progression to amputation was 8.4% following midfoot CNA reconstruction, with 2.8% of patients undergoing major amputation (below knee or above knee). Despite no statistical significance, we recommend surgeons to consider including an STJ arthrodesis in addition to midfoot CNA reconstruction to establish a stable and plantigrade foot.

Correlation Analysis Between Clinical Hypermobility Measurement and Radiographic Parameters of the Hallux Valgus Deformity

The finding of "hypermobility" has conventionally been considered as a dichotomous categorical variable in both clinical practice and in the literature. In other words, it is defined as being either "present" or "absent" in patients with hallux valgus. Yet it might be far more likely that this represents a continuous variable described by a bell-shaped distribution. Therefore the objective of this investigation was to consider hypermobility as a continuous variable, and to compare the sagittal plane first ray motion to radiographic parameters commonly used in the evaluation of the hallux valgus deformity by means of correlation analyses. The radiographs and measurements of 86 feet were included and measurement of sagittal plane first ray motion was performed with the validated Klaue device. No statistically significant correlation was observed between the total first ray motion with the first intermetatarsal angle (Pearson correlation coefficient 0.106; p = .333), hallux valgus angle (Pearson correlation coefficient -0.106; p = .330), nor sesamoid position (Pearson correlation coefficient 0.155; p = .157). The results of this investigation uniquely consider measurement of hypermobility as a continuous variable, and find no correlation between first ray sagittal plane motion and radiographic parameters associated with the hallux valgus deformity. These results might indicate that although the concept of hypermobility has traditionally been coupled with presentation of the hallux valgus deformity, this might simply represent the result of a historical confirmation bias.

The Role of Equinus in Flatfoot Deformity

Equinus plays an important role in flatfoot deformity. Proper evaluation and surgical management are critical to comprehensively treat and successfully resolved patients' symptoms. We have discussed the cause, evaluation, and some of the common surgical options. Each procedure has its inherent benefits and risks. It is imperative that the foot and ankle surgeon identify and include these procedures as part of the complete reconstructive surgery.

Progression to Hindfoot Charcot Neuroarthropathy After Midfoot Charcot Correction in Patients With and Without Subtalar Joint Arthrodesis

Charcot neuroarthropathy (CNA) is a disabling and progressive disease that affects the bones and joints of the foot. Successful Charcot reconstruction focuses on restoring anatomic alignment, obtaining multiple joint arthrodesis, selecting stable fixation, preserving foot length, and creating a foot suitable for community ambulation in supportive shoegear. Intramedullary fixation arthrodesis of the medial and lateral columns has been previously reported to produce improvement in midfoot Charcot reconstruction. More recently, a growing trend of stabilization of the subtalar joint (STJ) has been incorporated alongside the medial and lateral column fusion. Our objectives were to retrospectively review patients who underwent midfoot Charcot reconstructive surgery, whether with or without accompanying STJ arthrodesis, and establish which patients progressed to ankle CNA. Of the 72 patients who underwent midfoot Charcot reconstruction, 28 (38.9%) underwent STJ arthrodesis, and 22 converted to ankle CNA (30.6%). Fourteen (63.6%) of 22 ankle CNA cases had not undergone STJ arthrodesis; 8 patients (36.4%) had it. A Fisher exact test was performed to identify the relationship between those without STJ arthrodesis and those progressing to ankle CNA; it revealed statistical significance (P = 0.001). Performing an STJ arthrodesis with midfoot Charcot reconstructive surgery may be beneficial to aiding in hindfoot stability, establishing a plantigrade foot, and providing further insight into the management of midfoot Charcot. LEVEL OF CLINICAL EVIDENCE: III.

Factors Associated With Successful Closed Reduction of Dislocated Ankle Fractures at a US Level-1 Trauma Center

Dislocated ankle fractures represent a common presenting pathology at US emergency departments, and several different procedural and anesthetic techniques are employed for attempted closed reduction of these injuries. The objective of this investigation was to evaluate the frequency of and factors associated with success in the closed reduction of dislocated ankle fractures. A diagnostic code search produced 1050 ankle fractures presenting to an urban US level-1 emergency department. These medical records were interrogated and first categorized into whether or not a closed reduction was attempted. Those identified closed reduction attempts were further categorized into whether the attempt was successful. A comparative analysis was subsequently performed of variables associated with procedure success. Of the 1050, 97 (9.2%) required closed reduction and of these, 76 (78.4%) were successfully closed reduced on the first attempt. No differences were observed in initial procedure success with respect to subject age (p = .701), subject gender (p = .623), fracture laterality (p = 1.00), open versus closed injuries (p = .282), fracture mechanism (p = 1.00), utilized anesthetic technique (p value range 0.291-0.616), or the specialty performing the reduction (p-value range 0.402-1.00). A descriptive subanalysis was performed on those fractures with an unsuccessful first closed reduction attempt. It is our hope that this investigation adds to the body of knowledge with respect to a commonly performed procedure by foot and ankle surgeons.

Multiplanar, Multivariate Analyses of Hallux Valgus Radiographic Parameters

Hallux valgus is a complex condition understood to involve pathomechanics in all 3 of the cardinal planes. Despite this, the bulk of its historical evaluation has been in the transverse plane, and one might argue that the traditional and more commonly performed univariate and bivariate analyses within the literature do not comprehensively describe the potential interrelationships between the planes during perioperative assessment. Therefore this investigation aimed to evaluate relationships between common radiographic parameters measured in the three cardinal planes by means of a multivariate regression analysis. Serial analyses utilizing the first intermetatarsal angle, hallux valgus angle, tibial sesamoid position, proximal articular set angle, Engel's angle, first metatarsal inclination angle, and the sesamoid rotation angle were performed with varying dependent and independent variables. The tibial sesamoid position (p < .001) and proximal articular set angle (p = .014) were found to be independently associated with the first intermetatarsal angle, while the hallux valgus angle (p = .712), Engel's angle (p = .646), first metatarsal inclination angle (p = .097), and sesamoid rotation angle (p = .099) were not. The tibial sesamoid position (p = .003), proximal articular set angle (p < .001), Engel's angle (p = .006), and sesamoid rotation angle (p = .003) were found to be independently associated with the hallux valgus angle, while the first intermetatarsal angle (p = .712) and first metatarsal inclination angle (p = .400) were not. The first intermetatarsal angle (p < .001), hallux valgus angle (p = .003), and proximal articular set angle (p = .015) were found to be independently associated with the tibial sesamoid position, while Engel's angle (p = .400), the first metatarsal inclination angle (p = .088), and the sesamoid rotation angle (p = .649) were not. These findings appear to question a direct relationship between the first intermetatarsal angle and hallux valgus angle, as well as potentially infer a relationship between the frontal plane with the hallux valgus angle.

The Effect of Remnant Metatarsal Parabola Structure on Transmetatarsal Amputation Primary Healing and Durability

Although generally considered to be both a durable and functional procedure for limb preservation, the transmetatarsal amputation (TMA) has high rates of complication, failure, revisional operation, and progression to more proximal amputation. The objective of this investigation was to determine the effect of remnant metatarsal parabola structure on healing outcomes following TMA. A retrospective chart review was performed of subjects undergoing a complete TMA with primary closure. We considered 4 patterns of remnant metatarsal parabola structure. TMA pattern type 1 was a normal parabola with the remnant second metatarsal extending furthest distally and slightly longer than the remnant first and third metatarsals with a gradual lateral taper. TMA pattern type 2 was the first metatarsal remnant extending furthest distally with a gradual lateral taper. TMA pattern type 3 was a relatively long fifth metatarsal remnant without the presence of a gradual lateral taper. And TMA pattern type 4 was a relatively short first metatarsal remnant with a relatively long second metatarsal with a gradual lateral taper. Seventy-three transmetatarsal amputations in 73 subjects met selection criteria. Thirty-nine (53.4%) amputations healed primarily at 90 days. No statistically significant differences were observed between groups with respect to the 90-day primary healing rate (p = .571) or 1-year ambulation rate without wound recurrence or reoperation (p = .811). These results might indicate that the remnant metatarsal structure does not have an effect on transmetatarsal amputation outcome. It is our hope that these results add to the body of knowledge and lead to further investigations into outcomes of limb preservation surgical interventions.

Normal Distal Excursion of the Peroneus Brevis Myotendinous Junction

A low-lying peroneus brevis muscle belly has been described as a risk factor for the development of peroneal tendon pathology, but this finding has primarily been described based on cohorts with pre-existing clinical findings. Therefore, the objective of this investigation was to evaluate the frequency of apparently abnormal low-lying muscle bellies from a series of subjects without clinical or imaging findings of peroneal tendon pathology. One hundred consecutive MRIs were reviewed with measurement of the distance from the distal peroneal myotendinous junction to the tip of the fibula. This distance was observed to be 23.9 ± 8.8 mm (10.8-55.4 mm; 95% confidence interval 22.2-26.7 mm). If one assumed that a myotendinous junction within 2 cm of the distal tip of fibula represented an abnormal low-lying muscle, then we observed 37% of extremities without clinical or radiographic evidence of peroneal tendon pathology that would be considered anatomically "abnormal." When a low-lying muscle belly was defined as occurring within 2 cm of the distal tip of the fibula, then a probability analysis of our data distribution found a 32.6% probability for individuals to have an "abnormally" low-lying muscle belly. These results indicate that what has traditionally been defined intraoperatively as an abnormally low-lying peroneus brevis muscle belly might simply represent intraoperative confirmation bias of relatively normal structural anatomy.

An Evaluation of Basic Demographic Characteristics in Foot and Ankle Surgery From the American College of Surgeons National Surgical Quality Improvement Program

It has become increasingly prevalent in the foot and ankle surgical literature to evaluate outcomes and trends obtained from large databases. The objective of this investigation was to provide a broad descriptive analysis and compare basic demographic characteristics relating to foot and ankle surgery within the American College of Surgeons National Surgical Quality Improvement Program database. The 16 Current Procedural Terminology® (CPT) codes available within this database pertaining to foot and ankle surgery were studied. Several CPT codes were observed to be more frequently associated with male gender: 27650 (Achilles tendon repair), 27698 (Lateral ankle reconstruction), 27702 (Total ankle arthroplasty), 27766 (ORIF medial malleolus fracture), 27792 (ORIF lateral malleolus fracture), and 28805 (Metatarsal amputation). Several other CPT codes were observed to be more frequently associated with female gender: 27658 (Primary peroneal tendon repair), 27814 (ORIF bimalleolar fracture), 27822 (ORIF trimalleolar ankle fracture without posterior lip fracture), and 27823 (ORIF trimalleolar ankle fracture with posterior lip fracture). The elective case designation was observed to be more frequently associated with male gender (65.4 vs 58.7%; p < .001). These data have potential use in the development and interpretation of quality improvement/performance improvement protocols at individual health care delivery centers, as well as the interpretation of other published investigations utilizing this database.

A Critical Biomechanical Evaluation of Foot and Ankle Soft Tissue Repair

The objective of this article is to review the biomechanical stresses that occur during normal physiologic function of lower extremity soft tissue anatomic structures and to use this as a baseline for a critical analysis of the medical literature because it relates to surgical reconstruction following injury. The Achilles tendon, anterior talofibular ligament, plantar plate, and spring ligament are specifically evaluated.

The Effect of Hallux Valgus Surgery on the Transverse Plane Hallux Proximal Phalanx Position

The objective of this investigation was to evaluate the apparent movement of the hallux proximal phalanx in the transverse plane relative to the second metatarsal following hallux valgus surgery. Pre- and postoperative radiographs of a consecutive series of 45 feet undergoing hallux valgus surgery were analyzed. Significant improvements were observed in the first intermetatarsal angle (12.4 vs 7.5 degrees; p < .001), hallux valgus angle (24.3 vs 13.4 degrees; p < .001), tibial sesamoid position (4.6 vs 2.7; p < .001), and second metatarsal-hallux proximal phalanx angle (80.1 vs 84.6 degrees; p < .001). No difference was observed in the distance between the second metatarsal bisection and the medial aspect of the tibial sesamoid (31.7 vs 31.5 mm; p = .756) nor between the second metatarsal bisection and medial aspect of the hallux proximal phalanx base (34.6 vs 34.2 mm; p = .592). Significant differences were observed between the second metatarsal bisection and the central aspect of hallux proximal phalanx base (26.5 vs 23.9 mm; p < .001) and between the second metatarsal bisection and the lateral aspect of the hallux proximal phalanx base (19.3 vs 15.4 mm; p < .001). A statistically significant difference was observed in the change of distance between the second metatarsal bisection and the medial, central, and lateral aspects of the hallux proximal phalanx base (-0.4 vs -2.6 vs -3.9 mm; p = .002). These results indicate that the hallux proximal phalanx does not translocate in the transverse plane following hallux valgus surgery, but instead pivots about the medial aspect of the joint.

Multivariate Analysis of Hallux Valgus Radiographic Parameters

This investigation aimed to better understand the complex relationship of common radiographic measurements performed during the perioperative evaluation of the hallux valgus deformity while accounting for interactions and potential interdependence. Several analyses utilizing the first intermetatarsal angle, hallux valgus angle, tibial sesamoid position, Engel's angle, subject age and subject gender were performed with varying independent and dependent variables. The hallux valgus angle (p < .001), tibial sesamoid position (p < .001), and Engel's angle (p < .001) were found to be independently associated with the first intermetatarsal angle. The first intermetatarsal angle (p < .001), tibial sesamoid position (p < .001), and Engel's angle (p < .001) were found to be independently associated with the hallux valgus angle. This suggests that there is significant interdependence of these variables during a preoperative radiographic examination. However, only the change in tibial sesamoid position (p < .001) was found to be independently associated with the change in the first intermetatarsal angle following surgical correction, while no studied variables were found to be independently associated with the change in hallux valgus angle following surgical correction. This suggests that correction of the intermetatarsal angle and tibial sesamoid position might not always reliably predict correction of the hallux valgus angle following surgical intervention. It might also suggest that additional procedures beyond metatarsal osteotomies are required to reliably correct the hallux valgus angle in some deformities. It is hoped that this investigation adds to the body of knowledge with respect to the perioperative radiographic evaluation of the hallux valgus deformity.

Surgical Anatomy of the Endoscopic Gastrocnemius Recession

The objective of this investigation was to analyze the surgical anatomy of the endoscopic gastrocnemius recession procedure with reference to the curved nature of the aponeurosis. A consecutive series of 34 magnetic resonance imaging scans were evaluated under the direction of a musculoskeletal radiologist. An angular calculation of the effective curvature of the aponeurosis was measured 2 cm distal to the musculotendinous junction based on the maximal posterior excursion and terminal medial and lateral edges. A frequency count was additionally performed of the number of deep intramuscular septa extending from the aponeurosis, as well as a description of the location of the neurovascular bundle in this location. The mean effective curvature was 126.5 degrees (standard deviation [SD] = 6.3 degrees, range 115-143 degrees, 95% confidence interval 124.3-128.7 degrees). We observed an average of 1.2 (SD = 0.5, range = 0-2) deep intramuscular septa extending from the aponeurosis, and that 20.6% of neurovascular bundles were located superficial to the aponeurosis in this location. In conclusion, we found that a straight cannula needs to be navigated around an approximate 125-degree angle during performance of the EGR procedure. We think that this information provides evidence of potentially unrecognized complications of this procedure and leads to future investigations demonstrating anatomic and procedural outcomes.

Responsiveness and Inter-Rater Reliability of the Pulse Volume Recording Upstroke Ratio (PVRr)

The objective of this study was to evaluate a measure of the responsiveness and reliability of the pulse volume recording upstroke ratio (PVRr). A database of 389 subjects undergoing lower extremity revascularization was analyzed. Subjects were included in the analysis if they had undergone pedal radiographs, had PVRs performed pre- and postlower extremity revascularization, and had regular pulsatile digital waveforms with a pressure recording on both PVRs. The responsiveness of the PVRr was assessed by means of the postoperative percent change in comparison to the digital pressures. A statistically significant negative correlation was observed (Pearson -0.421; p = .007) indicating that as digital pressures increased, the PVRr decreased. Further, measurement of the reliability of the PVRr was performed on a selection of 10 recordings by 2 residents and 3 board-certified surgeons. The observed intraclass correlation coefficient of measurements was 0.960. Results of this investigation provide evidence in support of the responsiveness and inter-rater reliability in the calculation of the pulse volume recording upstroke ratio.

Approximation of the Ankle-Brachial Index in the Setting of Medial Arterial Calcific Sclerosis

The presence of medial arterial calcific sclerosis is known to cause inaccuracy in the interpretation of noninvasive vascular testing. This substantially limits the utility of an important baseline diagnostic test for peripheral arterial disease. Therefore, the objective of this investigation was to derive a method to effectively factor out calcification in the interpretation of the ankle and digital brachial indices. The noninvasive vascular testing results of 160 subjects were stratified into the absence of calcification, mild calcification, moderate calcification, and severe calcification based on plain film radiographic findings of the infrageniculate vessels. Measurements were then performed of the pulse volume recording (PVR) waveforms at brachial, ankle and digital anatomic levels to include PVR wavelength and PVR upstroke length, with a calculation of the ratio of PVR upstroke length to PVR wavelength. These measurements were compared between groups and then correlated to the ankle and digital brachial indices. A significant difference was observed in the PVR upstroke ratio between the 3 anatomic levels (0.1818 vs 0.2622 vs 0.3191; p < .001), but not between the 4 calcification groups (0.2457 vs 0.2363 vs 0.2694 vs 0.2631; p = .242). A significant negative correlation was observed between the PVR upstroke ratio and the ankle brachial index (ABI) (Pearson -0.454; p = .002) with linear regression indicating the relationship is defined by the formula: Effective ankle brachial index = 1.17 - (1.33 × PVR upstroke ratio at ankle level). A significant negative correlation was also observed between the PVR upstroke ratio and the digital brachial index (Pearson -0.553; p < .001) with linear regression indicating the relationship is defined by the formula: Effective toe brachial index = 1.04 - (1.61 × PVR upstroke ratio at digital level). The results of this investigation demonstrate the feasibility of, and provide equations to approximate, the effective ankle brachial and toe brachial indices in the setting of medial arterial calcification.

Anatomic and Treatment Descriptive Features of Foot Infections Presenting With Radiographic Soft Tissue Emphysema

Foot infections associated with soft tissue emphysema, or the radiographic appearance of gas, are widely considered to necessitate urgent decompression with excisional debridement of the necrotic and infectious tissue burden. The objective of this investigation was to describe anatomic features and clinical outcomes associated with the presence of soft tissue emphysema in foot infections. A retrospective chart review was performed of 62 subjects meeting selection criteria. These were primarily male (74.2%), with a history of diabetes mellitus (85.5%), and without a history of previous lower extremity revascularization (98.4%). The primary radiographic location of the soft tissue emphysema was most frequently in the forefoot (61.3%), followed by the midfoot (21.0%), and rearfoot (16.1%). The soft tissue emphysema was most frequently observed primarily in the dorsal foot tissue (49.2%), followed by both dorsal and plantar foot tissue (27.4%), and the plantar foot tissue (24.2%). The soft tissue emphysema was confined to the primary anatomic location in 74.2% of subjects, while 25.8% of cases demonstrated extension into a more proximal anatomic area. Eighty-two percent of subjects underwent a bedside incision and drainage procedure on presentation in the emergency department, and 95.2% underwent a formal incision and drainage procedure in the operating room at 1.05 ± 0.79 (0-5) postadmission days. Twenty-seven percent of subjects had an unplanned 30-day readmission and 17.7% underwent an unplanned reoperation within 30 days following the index discharge. Fifty-two percent of subjects underwent a minor or major amputation during the index admission, while 33.9% eventually resulted in major limb amputation within 12 months. We hope that this investigation adds to the body of knowledge and provides expectations with respect to the evaluation and treatment of foot soft tissue infections complicated by the presence of radiographic soft tissue emphysema.

A Comparison of Adverse Short-Term Outcomes Following Forefoot Amputation Performed on an Inpatient Versus Outpatient Basis

The objective of this investigation was to evaluate short-term adverse outcomes following forefoot amputation with a specific comparison between those procedures performed on an inpatient versus outpatient basis. The 2018 American College of Surgeons National Surgical Quality Improvement Program database was interrogated to select those subjects with a 28805 current procedural terminology code (amputation, foot; transmetatarsal) that underwent the procedure with "all layers of incision (deep and superficial) fully closed." This resulted in 326 subjects who underwent the procedure on an inpatient basis and 72 subjects who underwent the procedure on an outpatient basis. Results of the primary outcome measures found no significant differences between groups with respect to the development of a superficial surgical site infection (5.8% vs 5.6%; p = .950), deep incisional infection (3.4% vs 5.6%; p = .380), or wound disruption (3.4% vs 6.9%; p = .163). Additionally, no significant differences were observed between groups with respect to unplanned reoperations (15.6% vs 12.5%; p = .500) or unplanned hospital readmissions (21.8% vs 23.6%; p = .957). The results of this investigation demonstrate no difference in short-term adverse outcomes following the performance of forefoot amputation with primary closure when the procedure is performed on an inpatient or outpatient basis. We hope that this information is utilized in future investigations specifically examining this clinical scenario as it relates to hospital admission criteria related to lower extremity tissue loss, length of hospital stay considerations, the timing of partial foot amputation following revascularization, and the economics of limb preservation.

An Evaluation of Patient Characteristics Associated With Medical Disposition in the Surgical Treatment of Ankle Fractures

The objective of this investigation was to evaluate patient characteristics associated with medical disposition in treatment of ankle fractures. The 2018 American College of Surgeons National Surgical Quality Improvement Program database was interrogated with data extracted related to the 6 current procedural terminology (CPT) codes available pertaining to ankle fractures: 27766, 27769, 27792, 27814, 27822, and 27823. The primary outcome analysis involved a comparison of patient characteristics and short-term adverse outcomes between those fractures repaired on an inpatient basis versus outpatient basis. A secondary analysis was then performed on patient characteristics and adverse short-term outcomes between those fractures treated on an inpatient basis who were discharged home versus elsewhere. Age (p < .001), race (p < .001), ethnicity (p < .001), body mass index (BMI) (p < .001), estimated probability of mortality (p < .001), estimated probability of morbidity (p < .001), CPT code of fracture designation (p < .001), functional status (p < .001), elective surgery designation (p < .001), American Society of Anesthesiologists class (p < .001), diabetes (p < .001), smoking status (p < .001), dyspnea (p < .001), COPD (p < .001), congestive heart failure (p < .001), hypertension (p < .001), dialysis (p < .001), cancer (p < .001), steroid use (p < .001), blood transfusion history (p < .001), and sepsis/systemic inflammatory response syndrome history (p < .001) were all independently associated with the ankle fracture repair being performed on an inpatient basis on regression analysis. Age (p < .001), race (p = .025), ethnicity (p < .001), BMI (p = .001), CPT code of fracture designation (p < .001), preoperative functional status (p < .001), and American Society of Anesthesiologists class (p < .001) were all independently associated with inpatient ankle fracture repairs being discharged to home following the procedure on regression analysis. The results of this investigation demonstrate that differences in patient demographic characteristics might contribute to medical decision-making as it relates to patient management and discharge disposition in the treatment of ankle fractures.

Descriptive Quantitative Analysis of First Metatarsal Sagittal Plane Motion

Evaluation of the sagittal plane motion of the first ray is a commonly accepted physical examination technique performed during the assessment and treatment of the hallux valgus deformity. Excessive or abnormal motion in this location, termed "hypermobility," has also traditionally been strongly associated with surgical decision-making and serves as a widely accepted indication for performance of the first metatarsal-medial cuneiform arthrodesis procedure. The objective of this investigation was to perform an analysis of first ray sagittal plane motion from a large population in order to determine the descriptive quantitative characteristics of the data set. First metatarsal sagittal plane motion was measured from a group of 149 subjects (298 feet) with a Klaue device. The mean total first metatarsal sagittal plane motion was 9.37 ± 2.39 mm (3.97-18.76). The data set was found to demonstrate many of the characteristics of a normally distributed population based on the histogram distribution, skewness (0.651), and kurtosis (0.761). No difference was observed between measurement of total sagittal plane motion between right and left feet (9.13 ± 2.37 mm vs 9.61 ± 2.40 mm; p = .081), nor between male and female subjects (9.29 ± 2.27 mm vs 9.58 ± 2.70 mm; p = .352). No substantial correlation was observed between total sagittal plane motion and subject age (Pearson correlation -0.053; p = .522). Results indicate that first ray sagittal plane motion might be best considered as a continuous variable as opposed to categorical variable, and might help objectify the difference between "normal" and "abnormal" motion.

Evaluation of the Relationship Between Aspects of Medical Complexity and Work Relative Value Units (wRVUs) for Foot and Ankle Surgical Procedures

Work relative value units (wRVUs) have been assigned to current procedural terminology codes in an effort to help establish physician compensation. However, the ability of these to accurately and efficiently capture the time, technical, and perioperative managerial aspects required of various procedures has recently been called into question for several surgical subspecialties. Therefore, the objective of this investigation was to evaluate various measures of medical complexity against wRVUs for foot and ankle surgical procedures. The 2018 American College of Surgeons National Surgical Quality Improvement Program database was utilized to identify and extract data related to the perioperative medical complexity of 16 foot and ankle surgical current procedural terminology codes. We observed a "weak" positive relationship between wRVUs and operation time as defined by a correlation coefficient of 0.234 (p < .001). Other variables associated with medical complexity in the perioperative period were found to significantly vary between wRVUs categories, but these differences were neither consistently nor directly associated with assigned relative values. We conclude that wRVUs might not always represent an efficient means for determining compensation for foot and ankle surgical procedures.

Level of Agreement Between Systematic Doppler Examination of the Lower Extremity and Diagnostic Angiography in the Setting of Peripheral Arterial Disease

BACKGROUND

The objective of this investigation was to determine the level of agreement between a systematic clinical Doppler examination of the foot and ankle and diagnostic peripheral angiography.

METHODS

The described Doppler examination technique attempted to determine the patency, quality, and direction of the flow through the dorsalis pedis artery, posterior tibial artery, terminal branches of the peroneal artery, and vascular arch of the foot. These results were then compared with angiographic distal run-off images as interpreted by a blinded vascular surgeon.

RESULTS

Levels of agreement with respect to artery patency/quality ranged from 64.0% to 84.0%. Sensitivity ranged from 53.8% to 84.2%, and specificity ranged from 64.7% to 91.7%. Agreement with respect to arterial flow direction ranged from 73.3% to 90.5%.

CONCLUSIONS

We interpret these results to indicate that this comprehensive physical examination technique of the arterial flow to the foot and ankle with a Doppler device might serve as a reasonable initial surrogate to diagnostic angiography in some patients with peripheral arterial disease.

Evaluating the Impact of Medial Arterial Calcification on Outcomes of Infrageniculate Endovascular Interventions for Treatment of Diabetic Foot Ulcers

BACKGROUND

Medial arterial calcification (MAC) of the tibial and pedal arteries has been associated with an increased risk of amputation among people with diabetes. Endovascular interventions on infrageniculate vessels are frequently performed with the intent of treating peripheral artery disease (PAD) and decreasing the risk of amputation in those with diabetes. This study aimed to investigate how the extent of MAC impacts outcomes of endovascular procedures in people with diabetic foot ulcers (DFU).

METHODS

We identified all patients who had undergone infrageniculate angioplasty in the setting of DFU at our institution between 2009 and 2019. Subjects were assigned a MAC score based on the severity of MAC in each vessel visualized on plain radiographs of the ankle and foot. We evaluated the relationship between MAC and the primary outcome, major adverse limb event (MALE), using stratified Cox proportional modeling.

RESULTS

Among 99 subjects with DFU who had undergone infrageniculate angioplasty, MALE occurred in 50% (95% confidence interval [CI] 38%-61%) of patients within 1 year of intervention. On univariate Cox regression analysis, each 1 point increment in MAC score (hazard ratio [HR], 1.09; 95% CI 1.01-1.18), the third tertile of MAC score (HR, 2.27; 95% CI 1.01-5.11), age (HR 0.96; 95% CI 0.93-0.99), and wound grade (HR, 5.34; 95% CI 2.17-13.14), were significantly associated with increased risk of MALE. On adjusted analysis stratified by wound grade, MAC score was found to be associated with MALE only in patients with a low wound grade.

CONCLUSION

Increased severity of MAC is associated with increased risk of MALE for subjects undergoing infrageniculate angioplasty with a low wound grade. Further research is needed to better understand the complex relationships of MAC, PAD, DFU, and interventions aimed at promoting healing of DFU.

Retrospective chart review of perioperative pain management of patients having surgery for closed ankle fractures using peripheral nerve blocks at a level one trauma center

Chronic opioid use is unfortunately perceived among these postoperative patients, specifically within orthopedic surgery. Patients having orthopedic surgeries are at risk for becoming addicted to opioids, and one benefit of peripheral nerves blocks could be to provide an alternative mode of pain control. This study takes a retrospective look at the use of peripheral nerve blocks for pain control following surgery for isolated traumatic ankle injuries. We hypothesize that when peripheral nerve blocks are administered preoperatively to patients with closed ankle fractures, they will have overall better control of postoperative pain compared to patients who did not receive a peripheral nerve block.

OBJECTIVES

The objective of this investigation was to evaluate the effect of preoperative peripheral nerve blockade on pain outcomes after ankle fracture surgery.

METHODS

After approval from our institutional review board, a Current Procedural Terminology code search was performed of all patients within our institution over a 3-year data collection period (August 2016-June 2019). This resulted in 177 subjects who underwent isolated closed ankle fracture open reduction internal fixation (ORIF), of which 71 subjects met inclusion criteria.

RESULTS

Results of the primary outcome measures found no difference in the mean postoperative care unit (PACU) pain scores between the groups (2.39 ± 2.91 vs 3.52 ± 3.09; P = 0.1724) nor the frequency of those who reported only mild pain (63.0% vs 47.10%; P = 0.2704). Subjects who received a peripheral nerve block spent more time in the PACU before discharge (2.06 ± 1.05 vs 0.94 ± 1.21 hours; P = 0.0004). Subjects receiving a peripheral nerve block were more likely to be given no analgesics in the PACU (38.9% vs 11.8%; P = 0.042) and less likely to receive a narcotic analgesic in the PACU (53.7% vs 82.4%; P = 0.047).

CONCLUSION

Although the results of this investigation demonstrate no significant difference in the mean PACU pain scores, they do demonstrate a significant difference in the amount of pain medication given in the PACU setting. This information will be used for future investigations of this discrepancy between pain perception and need for immediate postoperative pain medications as it relates to multimodal pain control in the setting of ankle fracture surgery.

Attrition in Podiatric Medicine and Surgery Residency

BACKGROUND

The objective of this study was to investigate the rate of attrition within podiatric medicine and surgery residency training programs.

METHODS

Between the academic years 2006-2007 and 2015-2016, the Temple University School of Podiatric Medicine matched 780 graduates into 163 different residency training programs. Program directors from these sites were individually contacted by e-mail and asked whether the specific Temple University School of Podiatric Medicine graduates who originally matched with their program 1) completed the program, 2) transferred to another program, 3) quit the program, or 4) were fired from the program.

RESULTS

Results were returned with respect to 614 (78.7%) of the 780 graduates, representing 103 (63.2%) of the 163 training programs. Program directors reported that 573 (93.3%) of the 614 graduates completed the program, 17 (2.8%) transferred from the program, six (1.0%) quit the program, five (0.8%) were fired by the program, and 13 (2.1%) matched but never started the program. This equates to an annual attrition rate of 0.46% for residents who started the podiatric residency training program that they matched with.

CONCLUSIONS

We conclude that the rate of attrition in podiatric medicine and surgery residency training appears to be relatively low or at least in line with other medical specialties, and hope that this information leads to other investigations examining attrition, specifically as it relates to physician-specific and program-specific risk factors for attrition.

Perceived Stress of Podiatric Medical Students

BACKGROUND

The primary objective of this investigation was to objectify perceived stresses of students enrolled at a US college of podiatric medicine.

METHODS

Following preliminary pilot data collection and representative student interviews, the Perceived Stress Scale and a newly developed survey consisting of 46 potential stresses were administered to students. Participants were asked to identify up to ten items from the survey that caused them the most stress and to further identify up to three of these ten that they considered to be the most stressful.

RESULTS

A response rate of 71.5% (261 of 365) was observed. Specific results demonstrate that levels of perceived stress in podiatric medical students are higher than those in the general population, as well as some potential trends with respect to specific perceived stresses that change over time.

CONCLUSIONS

The results of this investigation provide quantitative evidence of perceived levels of stress and specific stresses of students enrolled at a US college of podiatric medicine. We hope that these findings increase awareness of stress in podiatric medicine, lead to colleges of podiatric medicine taking active steps to improve student stress education, and lead to future investigations of stress and mental health in the field of podiatric medicine.

Level of Agreement with the Microscopic Analysis of Joint Aspirate for the Diagnosis of Gout in the Lower Extremity

BACKGROUND

Although clinical findings, laboratory serum markers, and radiographic images are also used, the purported gold standard or standard reference test for the diagnosis of gout is microscopic analysis of aspirated joint fluid. This observational investigation sought to identify the level of agreement with the microscopic analysis of joint fluid aspirate for the diagnosis of gout in the lower extremity between two departments in a single health-care center.

METHODS

A retrospective medical record review identified consecutive patients seen for suspected gout who underwent diagnostic joint aspiration. Patients were included if a lower-extremity joint synovial fluid sample was obtained and were excluded if they were not independently evaluated by both the departments of rheumatology and pathology. We categorized the documented joint fluid findings into four groups: no crystals, sodium urate crystals, calcium pyrophosphate dihydrate crystals, or both sodium urate and calcium pyrophosphate dihydrate crystals. We defined a "clinically significant disagreement" as one department observing any type of crystals and the other department observing no crystals.

RESULTS

We observed a clinically significant disagreement rate of 23.26% (intraclass correlation coefficient = 0.496). The department of rheumatology was more likely to observe the presence of crystals in a sample compared with the department of pathology (88.37% versus 65.12%; P = .02).

CONCLUSIONS

These results provide evidence that microscopic analysis of joint fluid aspirate might lack the accuracy and reliability needed to be considered a gold standard diagnostic test for gout in the lower extremity.

Printed 3-Dimensional Computed Tomography Scanned Ankle Fractures as an Educational Instrument

The evaluation of and treatment protocols for ankle fractures represents an important aspect of the education of podiatric medical students. The objective of this investigation was to examine the feasibility of and student satisfaction with using 3-dimensional (3D) printed bone models representative of the Lauge-Hansen classification. The computed tomography scans of subjects with actual rotational ankle fractures representative of the Lauge-Hansen classification were identified and extracted into a format compatible with a 3D printer. The models were approximately 20 cm in height and made of acrylonitrile butadiene styrene plastic in ivory color. These were subsequently implemented into the curriculum of a traumatology course with third year podiatric medical students in the form of a hands-on workshop. Students expressed high levels of satisfaction with the use of these models, and most recommended their continued implementation within the curriculum. The results of this investigation indicate that 3D technology within podiatric medical education is feasible with high levels of student satisfaction.

Quantitative Assessment of the Obliquity of the First Metatarsal-Medial Cuneiform Articulation

The so-called obliquity of the first metatarsal-medial cuneiform articulation has been described as an atavistic trait of human foot morphology, and it is commonly proposed as a relative risk factor for development of the hallux abductovalgus (HAV) deformity. The objectives of this investigation were to 1) provide descriptive normative radiographic data on a series of first metatarsal-medial cuneiform articulations and 2) correlate these findings to other common radiographic parameters used to define the HAV deformity. We measured radiographic parameters including the first intermetatarsal angle, hallux abductus angle, tibial sesamoid position, Engel's angle, and 2 measures of obliquity in the transverse and sagittal planes on a consecutive series of 136 weightbearing foot radiographic projections from subjects without a history of foot/ankle surgery or fracture/dislocation. Measurements were considered as continuous variables, graphically depicted against each other on frequency scatter plots, and analyzed by means of Pearson correlation coefficients. Only 1 bivariate comparison demonstrated a weak negative correlation (Engel's angle versus Obliquity_1 [Pearson -0.259; p = .002]). The results of this investigation did not demonstrate a statistically significant or clinically substantial relationship between the obliquity of the first metatarsal-cuneiform joint and common radiograph parameters of the HAV deformity. Although not specifically studied here, these results might potentially indicate function, as opposed to structure, in the developmental pathogenesis of the HAV deformity.

Soft Tissue Reconstruction with Diabetic Foot Tissue Loss

Although substantial advances have been made in treatment of diabetic foot disease with respect to patient education, preventative measures, early intervention, and prophylactic procedures, most surgical interventions for this condition are reactionary. Patients still primarily present to emergency departments with acute infections and tissue necrosis. The surgical intervention for this results in soft tissue deficit, often with partial foot amputation, through excisional debridement of pathologic tissue. Minimizing this initial soft tissue loss, with subsequent reconstruction of the defect, forms the focus of this article with a detailed anatomic assessment of structures at risk in the forefoot, midfoot and rearfoot.

A Review of the Effect of Lower-Extremity Pathology on Automobile Driving Function

The effect of lower-extremity pathology and surgical intervention on automobile driving function has been a topic of contemporary interest in the medical literature. The objective of this review was to summarize the topic of driving function in the setting of lower-extremity impairment. Included studies involved lower-extremity immobilization devices, elective and traumatic lower-limb surgery, chronic musculoskeletal pathology, and diabetes as it relates to the foot and ankle, focusing on the effect each may have on driving function. We also discuss the basic US state regulations with respect to impaired driving and changes to automobile structure that can be made in the setting of lower-extremity pathology.

Early Weightbearing After Arthrodesis of the First Metatarsal-Medial Cuneiform Joint: A Systematic Review of the Incidence of Nonunion

Arthrodesis of the first metatarsal-medial cuneiform articulation is a reliable and effective surgery for correction of hallux abducto valgus deformity. However, one potential relative contraindication to the procedure is the extended period of non-weightbearing immobilization that is typically associated with the postoperative course. The objective of this investigation was to perform a systematic review of the incidence of nonunion after early weightbearing in patients who underwent arthrodesis of the first metatarsal-medial cuneiform articulation for correction of a hallux abducto valgus deformity. We performed a review of electronic databases with the inclusion criteria of retrospective case series, retrospective clinical cohort analyses, and prospective clinical trials with 15 or more participants; a mean follow-up period ≥12 months; a postoperative early weightbearing protocol (defined as ≤2 weeks); a clear description of the fixation construct; and a reported incidence rate of nonunion. Eight studies met our inclusion criteria, with a total of 443 arthrodeses analyzed. Of these, 16 (3.61%) were described as developing a nonunion. This would likely be considered an acceptable rate of nonunion when considering this procedure and might indicate that the Lapidus procedure does not always require an extended period of postoperative non-weightbearing immobilization.

Level of Agreement With a Multi-Test Approach to the Diagnosis of Diabetic Foot Osteomyelitis

Although bone biopsy has historically been considered the "gold standard" or "standard reference" for the diagnosis of diabetic foot osteomyelitis, some contemporary investigations have provided evidence against this as a single diagnostic test and in support of a combination of clinical, laboratory, and radiographic findings. The objective of this investigation was to measure the level of agreement between several commonly used forms of diagnostic testing for diabetic foot osteomyelitis. A retrospective chart review was performed of 50 consecutive patients admitted to a single tertiary healthcare center with the documented performance of 1) a clinical probe-to-bone test on hospital admission; 2) plain film radiographs prior to any surgical intervention; 3) magnetic resonance imaging prior to any surgical intervention; and an intraoperative excisional bone debridement performed, with samples sent for both 4) histologic analysis and 5) microbiologic analysis. A frequency count of agreement among these 5 tests was performed, and the interobserver (or inter-test) agreement was measured using the kappa statistic. We observed low levels of inter-test agreement between the 5 diagnostic tests (range 42.0%-62.0%), and levels of chance-corrected agreement were well below what would be considered appropriate for a "gold standard" or "standard reference." Levels of the kappa statistic ranged from 0.0 to 0.220, with most inter-test comparisons falling in the "poor agreement" and "slight agreement" interpretation ranges. The highest level of agreement occurred between the plain film radiographs and magnetic resonance imaging (62.0% agreement and kappa statistic of 0.220). Although it is likely that a combination of clinical, radiographic, and laboratory tests provides the best diagnostic approach for diabetic foot osteomyelitis, the data provided herein indicate that the tests themselves might have high intrinsic levels of unreliability and that the specific combination of tests that might be best used remains unclear.

Reliability, Surgeon Preferences, and Eye-Tracking Assessment of the Stress Examination of the Ankle Syndesmosis

The diagnosis and stabilization of ankle syndesmotic injuries after acute injury remains an area of controversy in the foot and ankle surgical literature, seemingly without universal consensus. The primary objective of this investigation was to determine the frequency of agreement and reliability of the stress examination of the ankle syndesmosis. Secondary objectives were to determine surgeon preferences and protocols with respect to the ankle syndesmosis and to use gaze recognition software to perform an eye-tracking assessment during performance of stress examinations. Twelve foot and ankle surgeons, 12 residents, and 12 students were shown 5 intraoperative fluoroscopic still images and videos of the stress examination of the ankle syndesmosis. They were asked to evaluate the result as being "positive" or "negative" for syndesmotic stability. The overall reliability of the interpretation of the stress examination of the ankle syndesmosis was a kappa of 0.123 (surgeons 0.087; residents 0.019; students 0.237), indicating "slight" agreement. Survey results indicated wide variability in the perioperative preferences and protocols of surgeons dealing with the evaluation and treatment of the ankle syndesmosis. Eye-tracking results also demonstrated variability in the anatomic structures of interest focused on during performance of this testing. The results of this investigation provide evidence of reliability well below what would be expected of a gold standard test during stress examination of the ankle syndesmosis. These results indicate that future scientific endeavors are required to standardize the performance and interpretation of this testing.

Evaluation of the Mechanical Axis of the First Ray Before and After First Metatarsal-Phalangeal Joint Reconstructive Surgery

LaPorta et al published a description of measurement of the mechanical axis of the first ray in an attempt to introduce center-of-rotation angulation principles into forefoot reconstructive surgery. They found significant differences in the measurement of the first intermetatarsal angle between groups of feet with and without hallux abducto valgus deformity, but they found no difference in the measurement of the M1-M2 mechanical axis angle between groups. The objectives of this study were to further investigate the proposed M1-M2 mechanical axis angle and to examine the effect of hallux abducto valgus corrective surgery on its measurement. We retrospectively evaluated weight-bearing dorsal-plantar projection radiographs taken in the angle and base of gait of 56 consecutive feet before and after first metatarsal-phalangeal joint corrective surgery. On each radiograph, we calculated the first intermetatarsal angle, the hallux abductus angle, the tibial sesamoid position, the M1-M2 mechanical axis angle, and the position of the sesamoids relative to the mechanical axis of the medial column. Statistically significant decreases were observed when comparing pre- versus post-operative measurement of the first intermetatarsal angle (-4.83°; p < .001), hallux abductus angle (-11.46°; p < .001), and tibial sesamoid position (-1.99 positional grade; p < .001). Statistically significant differences were also observed for the M1-M2 mechanical axis angle (-0.47°; p = .007) and the position of the sesamoids relative to the mechanical axis of the medial column (0.38 positional grade; p < .001), but it is unlikely that these results would be considered clinically significant given the differences of less than 1° and less than 1 positional grade, respectfully. The results of this investigation add to the body of knowledge and will hopefully lead to future investigations into the progression, evaluation, and treatment of the hallux abducto valgus deformity.

Anatomic Feasibility of Distal Fibula Bicortical Screw Fixation With Lateral Neutralization Plating for Rotational Ankle Fractures

A common technique for fixation of rotational fibular fractures is to use an interfragmentary compression screw with a laterally positioned neutralization plate. The objective of the present investigation was to examine the anatomic feasibility of distal fibula bicortical fixation within this plating technique. A specific screw insertion technique was performed through a laterally positioned one-third tubular plate on a consecutive series of 81 intact cadaveric ankle mortises. The most distal plate hole was drilled, aimed 10° posterior to the midline of the fibula. The second-most distal plate hole was drilled, aimed 25° superiorly. The specimens were then dissected, and the screw termini were physically examined for whether they had penetrated the articular cartilage of the ankle mortise. The length of the most distal bicortical screw measured a mean ± standard deviation of 20.44 ± 2.49 (range 14 to 26) mm, with an extra-articular terminus in 95.06% of specimens. The length of the second-most distal bicortical screw measured a mean ± standard deviation of 19.68 ± 3.02 (range 12 to 28) mm, with an extra-articular terminus in 100% of the specimens. The results of the present study provide evidence that bicortical distal fibular fixation in accordance with basic fixation principles is anatomically possible and feasible with a one-third tubular plate. This could potentially obviate the need for more expensive fixation options (i.e., locked plates or anatomically contoured plates) and fixation options that are biomechanically stable but potentially anatomically impeding (i.e., posterior antiglide plating).

Anatomic Limitations of the Transmetatarsal Amputation With Consideration of the Deep Plantar Perforating Branch of the Dorsalis Pedis Artery

The transmetatarsal amputation is considered a durable procedure with respect to limb salvage when managing the consequences of diabetic foot disease. The success of the procedure is, in part, determined by the preoperative appreciation of arterial and functional status. The objectives of the present investigation were to determine the length of the remaining first metatarsal required during transmetatarsal amputation to preserve the anastomotic connection of the deep plantar perforating artery and subsequent "vascular arch" of the foot and the insertion of the tibialis anterior tendon. The primary outcome measure of our investigation was a measurement of the distance between the first metatarsal-medial cuneiform articulation and the distal extent of the deep plantar perforating artery in 85 embalmed lower limbs. As a secondary outcome measure, the insertion of the tibialis anterior tendon was evaluated relative to the deep plantar perforating artery. The most distal extent of the deep plantar perforating artery was observed at a mean ± standard deviation of 15.62 ± 3.74 (range 6.0 to 28.28) mm from the first metatarsal-medial cuneiform articulation. Most (89.41%) of the arteries were found within 20 mm of the first metatarsal-medial cuneiform articulation. The insertion of the tibialis anterior tendon was found to be proximal to the deep plantar perforating artery in all specimens (100.0%). In conclusion, 2.0 cm of remnant first metatarsal might represent an anatomic definition of how "short" a transmetatarsal amputation can safely be performed in most patients when considering the vascular and biomechanical anatomy.

Triplanar Quantitative Radiographic Analysis of the First Metatarsal-Phalangeal Joint in the Hallux Abductovalgus Deformity

Although hallux abductovalgus (HAV) is widely considered to be a triplanar deformity involving the transverse, sagittal, and frontal planes, most of the published literature has focused on evaluating the deformity in only the transverse plane, and we are unaware of any investigation objectively evaluating the relationship among the 3 planes in the setting of HAV deformity. The objective of this investigation was to quantitatively evaluate radiographic measurement of the relationship between the transverse, sagittal, and frontal planes in the HAV deformity. Anteroposterior, lateral, and sesamoid axial radiographs from 42 consecutive feet were evaluated with measurement of the first intermetatarsal angle, hallux abductus angle, metatarsal sesamoid position, first metatarsal inclination angle, sesamoid rotation angle, and tibial sesamoid grade. Variables were graphically depicted against each other on frequency scatter plots with calculation of a regression line and Pearson's correlation coefficient. As transverse plane deformity increased, the frontal plane deformity also tended to increase and the first metatarsal inclination angle tended to decrease. And as frontal plane deformity increased, the first metatarsal inclination angle tended to decrease. To our knowledge, these are the first quantitative and objective data in support of a triplanar component to the HAV deformity, and we believe this reinforces the evaluation of this deformity with emphasis on all 3 planes.