Charcot Neuroarthropathy Is Associated With Higher Rates of Phantom Limb After Lower Extremity Amputation.

BACKGROUND: The incidence of phantom limb pain in patients with Charcot neuroarthropathy who undergo major amputation is not well described. The purpose of this study was to determine whether patients with Charcot neuroarthropathy and diabetes who underwent either a below-knee amputation (BKA) or above-knee amputation (AKA) had an increased rate of phantom limb pain compared with those with a diagnosis of diabetes alone. METHODS: Using international classification of disease (ICD) and common procedural terminology (CPT) codes, the TriNetX research database identified 10 239 patients who underwent BKA and 6122 who underwent AKA between 2012 and 2022. Diabetic patients with and without Charcot neuroarthropathy were compared in terms of demographics and relative risk of developing phantom limb pain after AKA or BKA. RESULTS: Age, sex, ethnicity, and race did not significantly differ between groups. Charcot neuroarthropathy was associated with significantly increased risk of phantom limb pain following both BKA (risk ratio [RR]: 1.2, 95% confidence interval [CI]: 1.1-1.3, P < .01) and AKA (RR: 1.6, 95% CI: 1.2-2.3, P < .0068). CONCLUSION: Our results indicate that patients with a coexisting diagnosis of Charcot neuroarthropathy who require BKA or AKA may have an increased risk of developing phantom limb pain. LEVELS OF EVIDENCE: Level III.

Vancomycin Powder Is Highly Cost-Effective in Total Ankle Arthroplasty.

Prosthetic joint infection (PJI) is a costly and potentially fatal complication in total ankle arthroplasty (TAA). Some surgeons apply topical vancomycin powder to minimize the risk of infection during TAA procedures. The purpose of our study was to determine the cost-effectiveness of using vancomycin powder to prevent PJI following TAA and to propose an economic model that can be applied by foot and ankle surgeons in their decision to incorporate vancomycin powder in practice. Using our institution's records of the cost of 1 g of topical vancomycin powder, we performed a break-even analysis and calculated the absolute risk reduction and number needed to treat for varying costs of vancomycin powder, PJI infection rates, and costs of TAA revision. Costing $3.06 per gram at our institution, vancomycin powder was determined to be cost-effective in TAA if the PJI rate of 3% decreased by an absolute risk reduction of 0.02% (Number Needed to Treat = 5304). Furthermore, our results indicate that vancomycin powder can be highly cost-effective across a wide range of costs, PJI infection rates, and varying costs of TAA revision. The use of vancomycin powder remained cost-effective even when (1) the price of vancomycin powder was as low as $2.50 to as high as $100.00, (2) infection rates ranged from .05 to 3%, and (3) the cost of the TAA revision procedure ranged from $1000 to $10 000.Levels of Evidence: IV.

Improving Randomized-Controlled Trials in Foot and Ankle Orthopaedics: The Need to Include Sociodemographic Patient Data.

BACKGROUND: The representation of sociodemographic data within randomized-controlled trials (RCT) regarding foot and ankle surgery is undefined. The purpose of this study was to determine the incidence of sociodemographic data being reported in contemporary foot and ankle RCTs. METHODS: Randomized-controlled trials within the PubMed database from 2016 to 2021 were searched and the full text of 40 articles was reviewed to identify sociodemographic variables reported in the manuscript. Data regarding race, ethnicity, insurance status, income, work status, and education were collected. RESULTS: Race was reported in the results in 4 studies (10.0%), ethnicity in 1 (2.5%), insurance status in 0 (0%), income in 1 (2.5%), work status in 3 (7.5%) and education in 2 (5.0%). In any section other than the results, race was reported in 6 studies (15.0%), ethnicity in 1 (2.5%), insurance status in 3 (7.5%), income in 6 (15.0%), work status in 6 (15.0%), and education in 3 (7.5%). There was no difference in sociodemographic data by journal (P = .212), year of publication (P = .216), or outcome study (P = .604). CONCLUSION: The overall rate of sociodemographic data reported in foot and ankle RCTs is low. There was no difference in the reporting of sociodemographic data between journal, year of publication, or outcome study. LEVEL OF EVIDENCE: Level II.

Factors Associated With Amputation Following Ankle Fracture Surgery.

Patients with diabetes mellitus (DM) are at increased risk of complications following ankle fracture surgery. Previous research suggests that patients of low socioeconomic status are at increased risk of amputation following orthopedic complications. The purpose of this research was to determine if low socioeconomic status increases risk of below-knee amputation (BKA) following ankle fractures among patients with DM. The National Inpatient Sample (NIS) was queried from 2010 to 2014 to identify 125 diabetic patients who underwent ankle fracture surgical fixation followed by BKA. Two cohorts (BKA vs no BKA) and a multivariate logistic regression model were created to compare the effects of independent variables, including age, sex, race, primary payer, median household income by ZIP code, hospital location/teaching status, and comorbidities. The most predictive variables for BKA were concomitant peripheral vascular disease (odds ratio [OR] 5.35, 95% confidence interval [CI] 3.51-8.15), history of chronic diabetes-related medical complications (OR 3.29, CI 2.16-5.01), age in the youngest quartile (OR 2.54, CI 1.38-4.67), and male sex (OR 2.28, CI 1.54-3.36). Patient race and median household income were not significantly associated with BKA; however, risk of BKA was greater among patients with Medicaid (OR 2.23, CI 1.09-4.53) or Medicare (OR 1.85, CI 1.03-3.32) compared to privately insured patients. Diabetic inpatients with Medicaid insurance are at over twice the odds of BKA compared to privately insured patients following ankle fracture. Furthermore, peripheral vascular diseases, uncontrolled diabetes, younger age, and male sex each independently increase risk of BKA.

Cost-Effective Modeling of Thromboembolic Chemoprophylaxis for Total Ankle Arthroplasty.

BACKGROUND: Symptomatic venous thromboembolism (VTE) following total ankle arthroplasty (TAA) can cause substantial morbidity and mortality. To prevent this complication, surgeons often prescribe postoperative chemoprophylaxis. However, much controversy exists regarding the efficacy of chemoprophylaxis because of the limited studies exploring its use. Furthermore, even less is known about its cost-effectiveness. Therefore, this study sought to determine the cost-effectiveness of commonly prescribed chemoprophylactic agents using a break-even analysis economic model. METHODS: The literature was searched, and an online database was used to identify patients who developed a symptomatic VTE after undergoing TAA. Our institutional records were used to estimate the cost of treating a symptomatic VTE, and an online drug database was used to obtain the cost of commonly prescribed chemoprophylactic agents. A break-even analysis was then performed to determine the final break-even rate necessary to make a drug cost-effective. RESULTS: The low and high rates of symptomatic VTE were determined to be 0.46% and 9.8%. From 2011 to 2021, a total of 3455 patients underwent total ankle arthroplasty. Of these patients, 16 developed a postoperative symptomatic VTE (1.01%). Aspirin 81 mg was cost-effective if the initial symptomatic VTE rates decreased by an absolute risk reduction (ARR) of 0.0003% (NNT = 31 357). Aspirin 325 mg was also cost-effective if the initial rates decreased by an ARR 0.02% (NNT = 5807). Likewise, warfarin (5 mg) was cost-effective at all initial rates with an ARR of 0.02% (NNT = 4480). In contrast, enoxaparin (40 mg) and rivaroxaban (20 mg) were only cost-effective at higher initial symptomatic VTE rates with ARRs of 1.48% (NNT = 68) and 5.36% (NNT = 19). Additional analyses demonstrated that enoxaparin (40 mg) and rivaroxaban (20 mg) become cost-effective when costs of treating a symptomatic VTE are higher than our estimates. CONCLUSION: Chemoprophylaxis following TAA can be cost-effective. A tailored approach to VTE prophylaxis with cost-effectiveness in mind may be beneficial to the patient and health system.

Utility and Associated Charge of Anteroposterior Radiographs in Rotational Ankle Fractures During Postoperative Follow-Up: The Results of an Orthopaedic Trauma Association Survey.

OBJECTIVES: To evaluate the perceived utility and associated charges of the anteroposterior (AP) radiograph during rotational ankle fracture postoperative follow-up. DESIGN: Survey study with charge analysis using published data at 50 orthopaedic hospitals in the United States. SETTING: Not Applicable. PARTICIPANTS: Orthopaedic Trauma Association Members with an active email address who were invited and interested in answering a survey. RESULTS: Ninety-four percent of respondents stated that they did routinely obtain an AP radiograph during rotational ankle fracture follow-up. However, 57% thought that the AP view should be eliminated from standard follow-up and only 51% found this view useful after initial treatment. CHARGE ANALYSIS: The mean difference between a 2-view and 3-view ankle radiograph series was $102.00. Using this value and the assumption that each patient with a rotational ankle fracture gets 3 follow-up radiographs, there is the potential for a charge reduction of $306 per patient. Assuming over 134,000 rotational ankle fractures, a charge reduction of 41 million US dollars (USD) per year is possible if the AP image is routinely removed. Actual savings are likely to be less based on agreed on payer rates. Although less easy to quantify, there is also a potential reduction of radiation exposure, radiologists' interpretation time, and data storage. CONCLUSIONS: Routine AP radiographs should potentially be eliminated from routine postoperative ankle x-ray protocols based on this survey of experienced orthopaedic surgeons. If this specific radiograph is ordered on a case-by-case basis, then significant savings may occur.

Animal model detects early pathologic changes of Charcot neuropathic arthropathy.

Charcot neuropathic arthropathy is a degenerative, debilitating disease that affects the foot and ankle in patients with diabetes and peripheral neuropathy, often resulting in destruction, amputation. Proposed etiologies include neurotraumatic, inflammatory, and neurovascular. There has been no previous animal model for Charcot. This study proposes a novel rodent model of induced neuropathic arthropathy to understand the earliest progressive pathologic changes of human Charcot. High-fat-diet-induced obese (DIO) Wild-type C57BL/6J mice (n = 8, diabetic) and age-matched low-fat-diet controls (n = 6) were run on an inclined high-intensity treadmill protocol four times per week for 7 weeks to induce mechanical neurotrauma to the hind-paw, creating Charcot neuropathic arthropathy. Sensory function and radiologic correlation were assessed; animals were sacrificed to evaluate hindpaw soft tissue and joint pathology. With this model, Charcot-DIO mice reveals early pathologic features of Charcot neuropathic arthropathy, a distinctive subchondral microfracture callus, perichondral/subchondral osseous hypertrophy/osteosclerosis, that precedes fragmentation/destruction observed in human surgical pathology specimens. There is intraneural vacuolar-myxoid change and arteriolosclerosis. The DIO mice demonstrated significant hot plate sensory neuropathy compared (P < 0.01), radiographic collapse of the longitudinal arch in DIO mice (P < 0.001), and diminished bone density in DIO, compared with normal controls. Despite exercise, high-fat-DIO mice increased body weight and percentage of body fat (P < 0.001). This murine model of diet-induced obesity and peripheral neuropathy, combined with repetitive mechanical trauma, simulates the earliest changes observed in human Charcot neuropathic arthropathy, of vasculopathic-neuropathic etiology. An understanding of early pathophysiology may assist early diagnosis and intervention and reduce patient morbidity and mortality in Charcot neuropathic arthropathy.

Biomechanical Effects of Δ9-Tetrahydrocannabinol (THC) and Cannabidiol (CBD), the Major Constituents of Cannabis, in a Sprague Dawley Rat Achilles Tendon Surgical Repair Model: A Pilot Study.

BACKGROUND: The use of cannabis is common among athletes and the US population at large. Cannabinoids are currently being evaluated as alternatives to opioid medications for chronic pain management. However, the effects of recreational and/or medical use of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) on musculoskeletal injury and healing remain largely unknown. HYPOTHESIS/PURPOSE: The purpose of this study was to evaluate the biomechanical effects of CBD and THC on tendon-to-tendon healing in a rat Achilles tendon repair model. The hypothesis was that rats administered CBD would demonstrate decreased tensile load to failure of surgically repaired Achilles tendons compared with the THC and control groups. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 33 Sprague Dawley rats underwent Achilles tendon surgical transection and repair and were randomized to receive subcutaneous injection of THC, CBD, or vehicle once daily starting on the day of surgery and for 5 total days. After sacrifice, biomechanical tensile load-displacement testing was performed to determine Achilles tendon load to failure and stiffness. Data were analyzed by 1-way analysis of variance. RESULTS: The THC group demonstrated the highest median load to failure, 18.7 N (95% CI, 15.3-19.2 N); the CBD group had the second highest at 16.9 N (95% CI, 15.1-19.8 N), and the control group had the lowest at 14.4 N (95% CI, 12.1-18.3 N). Stiffness was highest in the THC group at 4.1 N/mm (95% CI, 2.7-5.1 N/mm) compared with 3.6 N/mm (95% CI, 2.9-4.1 N/mm) for the CBD group and 3.6 N/mm (95% CI, 2.8-4.3 N/mm) for the control group. No statistically significant differences for strength and stiffness were observed between the groups. CONCLUSION: In this pilot study using an animal tendon-to-tendon repair model, neither THC nor CBD resulted in altered biomechanical characteristics compared to control. CLINICAL RELEVANCE: Cannabinoids do not appear to adversely affect Achilles tendon healing.

Comparing the Efficacy of True-Volume Analysis Using Magnetic Resonance Imaging With Computerized Tomography and Conventional Methods of Evaluation in Cystic Osteochondral Lesions of the Talus: A Pilot Study.

Background: Osteochondral lesions of the talus (OLT) often require advanced imaging if they prove to be refractory to preliminary microfracture. Orthopedic surgeons may misinterpret the size and morphology of the OLT when evaluating through conventional methods. The purpose of this study was to evaluate MRI as a modality for calculating true-volumes and compare its utility to that of CT true-volume and conventional methods of measuring lesion size. METHODS: With IRB approval, an institutional radiology database was queried for patients with cystic OLT that had undergone and failed microfracture and had compatible CT and MR scans between 2011 and 2016. Five lesions, previously analyzed and described in the literature using CT true-volume, were selected. 10 orthopedic surgeons independently estimated the volume of these 5 OLT via standard MRI. Next, 3D reconstructions were created and morphometric true-volume (MTV) analysis measurements of each OLT were generated. The percent change in volumes from CT and MR was compared based upon MTVs determined from 3D reconstructive analysis. RESULTS: The volume calculated using conventional methods in CT and MR scans grossly overestimated the size by of the OLT by 285-864% and 56-374% respectively when compared to 3D true-volume analysis of those CT and MR scans. CONCLUSIONS: This study demonstrates that true-volume is more accurate for calculating lesion size than conventional methods. Additionally, when comparing MRI and CT, thin slice CT true-volume is superior to MRI true-volume. True-volume calculation improves accuracy with CT and MRI and should be recommended for use in revision OLT cases.Levels of Evidence: Level III: Case control study.

Demographic Distribution of Foot and Ankle Surgeries Among Orthopaedic Surgeons and Podiatrists: A 10-Year Database Retrospective Study.

BACKGROUND: Foot and ankle surgeries in the United States (US) are currently performed by orthopaedic surgeons or podiatrists with specialty surgical training. With the trend in healthcare now placing increased emphasis on quality and standardizing patient care, this study aimed to characterize the distribution, volume, and trends of certain foot and ankle surgeries performed in the US by both orthopaedic surgeons and podiatrists. MATERIALS AND METHODS: A retrospective analysis was performed using the Marketscan Claims Database (Truven Health Analytics, Ann Arbor, Michigan) which covers most privately insured patients under the age of 65 in the USA from 2005 to 2014. We searched current procedural terminology (CPT) codes for total ankle replacement (TAR), triple arthrodesis, hallux valgus correction, pilon fracture open reduction and internal fixation (ORIF), calcaneus fracture ORIF, and ankle fracture ORIF. We recorded the timing and nature of procedures along with various features associated with the surgeon and the geographic location of the treatment facility. RESULTS: We found that the number of foot and ankle procedures performed annually is steadily increasing. Orthopaedic surgeons are the main treating surgeon for common foot and ankle traumatic conditions or complex hind foot cases like TAR. On the other hand, our study showed that podiatrists perform almost 9 out of 10 hallux valgus correction surgeries. DISCUSSION: Our study showed the trends in surgical volumes and differences between surgical podiatrists and orthopaedic surgeons and the evolution of these volumes over a ten year period and differences in surgical repertoire between orthopaedists and podiatrists.Levels of Evidence: Level IV: Case series, Clinical research.

Achilles tendon moment arm changes with total ankle arthroplasty.

Prior research on total ankle arthroplasty (TAA) has focused on improvements in pain and function following the surgical treatment of ankle arthritis, but its effect on ankle joint mechanics has received relatively little attention. The plantarflexion moment arm of the Achilles tendon is a critical determinant of ankle function with the potential to be altered by TAA. Here we investigate the effect of TAA on Achilles tendon moment arm assessed using two methods. Standing sagittal-plane radiographs were obtained for ten patients presurgery and postsurgery, from which anterior-posterior distance between the posterior calcaneus and the center of the talar dome was measured. Ultrasound imaging and three-dimensional (3D) motion capture were used to obtain moment arm pre- and post-TAA. The absolute changes in moment arm pre- to post-TAA were significantly different from zero for both methods (9.6 mm from ultrasound and 4.6% of the calcaneus length from radiographs). Only 46% of the variance in postoperative 3D Achilles tendon moment arm was explained by the preoperative value (r2 = 0.460; p = .031), while pre- and post-TAA values from radiographs were not correlated (r2 = 0.192, p = .206). While we did not find significant mean differences in Achilles tendon moment arm between pre- and post-TAA, we did find absolute changes in 3D moment arm that were significantly different from zero and these changes were partially explained by a change in location of the talar dome as indicated by measurements from radiographs (r2 = 0.497, p = .023).

Outcomes of NCAA Defensive Football Players Following Achilles Tendon Repair.

BACKGROUND: The incidence of Achilles ruptures has been on the rise in National Collegiate Athletic Association (NCAA) football players, but the career impact of this injury is not fully understood. In this study, we analyzed a large series of Achilles tendon injuries in NCAA Football Bowl Subdivision (FBS) defensive football players who required repair in order to determine their return to play, performance, and career outcomes afterward. METHODS: FBS defensive football players who required Achilles repair from 2010 to 2016 were identified. The return to play of the eligible underclassmen athletes was then determined and the preinjury and postoperative performances of players who met criteria were compared with matched controls. The number of underclassmen who went on to participate in the National Football League (NFL) Combine or play in at least 1 NFL game was also determined and compared with controls. RESULTS: Fifty-seven total Achilles ruptures were identified, 40 of which occurred in underclassmen, who returned at a rate of 92.5%. Of the players who met performance criteria, only defensive backs differed from matched controls in terms of solo tackling (P = .025) and total tackling (P = .038), while still increasing compared with preoperative performance. Only 5.0% of underclassmen performed at NFL Combine and only 7.5% competed in at least 1 NFL game (20.0% and 21.3%, respectively, for matched controls). CONCLUSION: Defensive FBS players returned at a high rate following Achilles rupture and did not seem to experience a significant drop-off in performance upon return. An Achilles rupture did appear to impact their chances of playing professionally in the future, however. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Cost Comparison of Synthetic Hydrogel Implant and First Metatarsophalangeal Joint Arthrodesis.

Background. First metatarsophalangeal (MTP) arthrodesis is the "gold standard" treatment for hallux rigidus. Recently, there has been increased interest in new synthetic cartilage implants to preserve joint motion while eradicating pain. With current health care economics, the cost of a treatment is gaining particular importance. This study set out to perform a cost comparison between MTP arthrodesis and synthetic hydrogel implant to determine which treatment modality is more cost-effective based on direct aggregate costs. Study design. Economic and decision analysis. Methods. Studies in the available literature were analyzed to estimate hardware removal rates for MTP fusion and failure rates for a synthetic hydrogel implant and MTP fusion. Costs were determined by examining direct costs at a single institution for implants and data reported in the literature for operating room time. Sensitivity analysis and Monte Carlo simulation were performed to examine cost and measurement uncertainty. Results. Assuming a 4.76% MTP arthrodesis revision rate and 7.06% hardware removal rate, the total direct cost of MTP joint arthrodesis was $3632. Using a 9.2% failure rate with subsequent conversion to MTP arthrodesis, the total cost of synthetic hydrogel implant was $4565. Sensitivity analysis revealed that MTP fusion was more cost-effective even if the failure rate increased to 15% and synthetic hydrogel implant failure rate was 0%. The synthetic cartilage implant cost would have to be reduced 28% or approximately 200% the cost of MTP fusion implants to be comparable to MTP arthrodesis. Conclusion. Hallux rigidus treatment with a synthetic hydrogel implant resulted in a higher direct aggregate cost than MTP arthrodesis.Level of Evidence: Level II: Cost analysis.

What Is the Definition of Acute and Chronic Periprosthetic Joint Infection (PJI) of Total Ankle Arthroplasty (TAA)?

RECOMMENDATION: There is a paucity of data for defining acute or chronic periprosthetic joint infection (PJI) following total ankle arthroplasty (TAA) in the literature. Any discussion of PJI after ankle replacement is entirely reliant on the literature surrounding knee and hip arthroplasty. LEVEL OF EVIDENCE: Consensus. DELEGATE VOTE: Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Biomechanical Evaluation of Spring Ligament Augmentation With the FiberTape Device in a Cadaveric Flatfoot Model.

BACKGROUND: The structural importance of the spring ligament complex in arch stability has been described. Furthermore, the pathology of this complex is often noted in patients with posterior tibial tendon dysfunction. The purpose of this biomechanical study was to evaluate spring ligament repair alone versus augmentation with the FiberTape device in a cadaveric flatfoot model. METHODS: Eight paired, below-the-knee, cadaveric specimens underwent flatfoot creation and reconstruction. The experimental group received augmentation with FiberTape (InternalBrace). After potting, specimens were loaded statically to measure talonavicular contact pressures and flatfoot correction. Cyclic loading was performed in a stepwise fashion. Loading was performed at 1 Hz and 100 cycles, at 100-N intervals from 500 to 1800 N, with the Achilles tendon also loaded to simulate weightbearing in the postoperative period. RESULTS: Control specimen analysis demonstrated failures of 8 of 8 (100%) spring ligament suture repairs, occurring through suture cut-through (5 specimens), suture fatigue and elongation (2), or knot failure (1). One of 8 (12.5%) FiberTape-augmented repairs failed after cyclic loading. The difference in number of repair failures was statistically significant between the 2 groups ( P = .0014). Analysis revealed that at forces of 1600 N ( P = .03) and 1700 N ( P = .02) there were statistically significant differences between the FiberTape-augmented group and the control group, with a greater collapse in the lateral Meary talo-first metatarsal angle in the controls. There was no significant difference or abnormal increase in contact pressures of the talonavicular joint in both groups. CONCLUSION: FiberTape augmentation of the spring ligament appears biomechanically safe and effective under cyclic loading. CLINICAL RELEVANCE: Spring ligament augmentation with this device may be another biomechanically safe and reasonable treatment modality for surgeons during flatfoot reconstruction. It is possible that early protected weightbearing after these procedures may be performed.

Diagnostic Criteria and Treatment of Acute and Chronic Periprosthetic Joint Infection of Total Ankle Arthroplasty.

BACKGROUND: Prosthetic joint infection (PJI) after total ankle arthroplasty (TAA) is a serious complication that results in significant consequences to the patient and threatens the survival of the ankle replacement. PJI in TAA may require debridement, placement of antibiotic spacer, revision arthroplasty, conversion to arthrodesis, or potentially below the knee amputation. While the practice of TAA has gained popularity in recent years, there is some minimal data regarding wound complications in acute or chronic PJI of TAA. However, of the limited studies that describe complications of PJI of TAA, even fewer studies describe the criteria used in diagnosing PJI. This review will cover the current available literature regarding total ankle arthroplasty infection and will propose a model for treatment options for acute and chronic PJI in TAA. METHODS: A review of the current literature was conducted to identify clinical investigations in which prosthetic joint infections occurred in total ankle arthroplasty with associated clinical findings, radiographic imaging, and functional outcomes. The electronic databases for all peer-reviewed published works available through January 31, 2018, of the Cochrane Library, PubMed MEDLINE, and Google Scholar were explored using the following search terms and Boolean operators: "total ankle replacement" OR "total ankle arthroplasty" AND "periprosthetic joint infection" AND "diagnosis" OR "diagnostic criteria." An article was considered eligible for inclusion if it concerned diagnostic criteria of acute or chronic periprosthetic joint infection of total ankle arthroplasty regardless of the number of patients treated, type of TAA utilized, conclusion, or level of evidence of study. RESULTS: No studies were found in the review of the literature describing criteria for diagnosing PJI specific to TAA. CONCLUSIONS: Literature describing the diagnosis and treatment of PJI in TAA is entirely reliant on the literature surrounding knee and hip arthroplasty. Because of the limited volume of total ankle arthroplasty in comparison to knee and hip arthroplasty, no studies to our knowledge exist describing diagnostic criteria specific to total ankle arthroplasty with associated reliability. Large multicenter trials may be required to obtain the volume necessary to accurately describe diagnostic criteria of PJI specific to TAA. LEVEL OF EVIDENCE: Level III, systematic review.

Short- to Mid-Term Outcomes Following the Use of an Arthroereisis Implant as an Adjunct for Correction of Flexible, Acquired Flatfoot Deformity in Adults.

BACKGROUND: The use of an arthroereisis implant for the treatment of adolescent flatfoot deformity has been described. However, data that address the outcomes of patients treated with an arthroereisis implant in adults are limited. The purpose of this study was to investigate the radiographic and clinical outcomes and complications following the use of a subtalar arthroereisis implant as an adjunct for correction acquired flatfoot deformity secondary to posterior tibial tendon dysfunction. METHODS: A retrospective case-control study was performed querying all patients undergoing surgical flatfoot correction between January 1, 2010 and January 1, 2015. The experimental group included patients undergoing arthroereisis augmentation at the time of flatfoot correction. Patients undergoing the same flatfoot correction without the use of an arthroereisis implant were used as controls. Radiographic measurements were evaluated preoperatively and at final radiographic follow-up and included talonavicular (TN) coverage angle, and lateral talar-first metatarsal angle (T1MA). Patient-reported outcomes were assessed using preoperative visual analog scale (VAS) pain scores and postoperative Short Form-36, VAS, and satisfaction at final orthopedic follow-up. RESULTS: A total of 15 patients underwent flatfoot correction and were augmented with an arthroereisis implant and were matched with 30 controls. Postoperative, mid-term T1MA and regional analysis was found to be improved in the experimental group versus control. Patients undergoing adjunct subtalar arthroereisis demonstrated an increased likelihood of achieving radiographically normal talonavicular coverage <7° compared with our control group at follow-up. CONCLUSIONS: The adjunct use of an arthroereisis implant resulted in improved and maintained radiographic and clinical measurements in patients undergoing stage II flatfoot. CLINICAL SIGNIFICANCE: These results suggest utility of a subtalar arthroereisis implant as an adjunct to flatfoot correction with little additional risk of harm to the patient. LEVELS OF EVIDENCE: Level III: Case-control study.

Three-Dimensional Morphometric Modeling Measurements of the Calcaneus in Adults with Stage IIB Posterior Tibial Tendon Dysfunction: A Pilot Study.

Background: The pathophysiology of adult-acquired flatfoot deformity (AAFD) is not fully explained by degeneration of the posterior tibial tendon alone. While a shortened or dysplastic lateral column has been implicated in flatfoot deformity in pediatrics, there is no study that has quantified the degree of dysplasia in adults with a stage IIb flatfoot deformity, or if any exists at all. Methods: An institutional radiology database was queried for patients with posterior tibial tendon dysfunction (PTTD) who had computed tomography (CT) performed. Controls were patients receiving CT scan for an intra-articular distal tibia fracture without preexisting foot or calcaneal pathology. Clinical notes, physical examination, and weightbearing radiographs were used to find patients that met clinical criteria for stage IIb PTTD. Morphometric measurements of the calcanei were performed involving the length of the calcaneal axis (LCA), height of the anterior process (HAP), and length of the anterior process (LAP). All measurements were performed independently by separate observers, with observers blinded to group assignment. We considered a difference of ±4 mm as our threshold. Results: 7 patients and 7 controls were available for reconstruction and analysis. On average, the LCA was 3.1 mm shorter in patients with stage IIb PTTD compared with controls (P < .05). The LAP was shorter in PTTD patients compared with controls 3.4 mm (P < .001). Conclusions: Our results support the hypothesis that the calcaneus of adult patients with stage IIb AAFD is dysplastic when compared with healthy controls, which further supports the utility of lateral column lengthening. Levels of Evidence: Level III: Case-control study.

The Role of 3D Reconstruction True-Volume Analysis in Osteochondral Lesions of the Talus: A Case Series.

BACKGROUND: Evaluation and management of osteochondral lesions of the talus (OLTs) often warrant advanced imaging studies, especially in revision or cases with cystic defects. It is possible that orthopedic surgeons may overestimate the size and misinterpret the morphology of OLT from conventional computed tomography (CT), thereby influencing treatment strategies. The purpose of this study was to determine the utility of a novel means to estimate the true-volume of OLTs using 3D reconstructed images and volume analysis. METHODS: With Institutional Review Board approval, an institutional radiology database was queried for patients with cystic OLTs that failed previous microfracture, having compatible CT scans and magnetic resonance imaging (MRI) between 2011 and 2016. Fourteen patients met inclusion criteria. Of these, 5 cases were randomly selected for 3D CT reconstruction modeling. Ten orthopedic surgeons independently estimated the volume of these 5 OLTs via standard CT. Then 3D reconstructions were made and morphometric true-volume (MTV) analysis measurements of each OLT were generated. The percent change in volumes from CT were compared to MTVs determined from 3D reconstructive analysis. RESULTS: On average, the volume calculated by conventional CT scanner grossly overestimated the actual size of the OLTs. The volume calculated on conventional CT scanner overestimated the size of OLTs compared to the 3D MTV reconstructed analysis by 285% to 864%. CONCLUSIONS: Our results showed that conventional measurements of OLTS with CT grossly overestimated the size of the lesion. The 3D MTV analysis of cystic osteochondral lesions may help clinicians with preoperative planning for graft selection and appropriate volume while avoiding unnecessary costs incurred with overestimation. LEVEL OF EVIDENCE: Level IV, case series.

Is Dual Semitendinosus Allograft Stronger Than Turndown for Achilles Tendon Reconstruction? An In Vitro Analysis.

BACKGROUND: Large Achilles tendon defects pose a treatment challenge. The standard treatment with a turndown flap requires a large extensile incision, puts the sural nerve at risk, and demands slow, careful rehabilitation. Dual allograft semitendinosus reconstruction is a new clinical alternative that has the theoretical advantages of a smaller incision, less dissection, and a stronger construct that may allow for faster rehabilitation. QUESTIONS/PURPOSES: In a cadaver biomechanical model, we compared the dual allograft semitendinosus reconstruction with the myofascial turndown in terms of (1) mechanical strength and resistance to deformation and (2) failure mechanisms in reconstruction of large segmental Achilles defects. METHODS: An 8-cm segmental Achilles defect was created in 18 cadaveric lower extremities, nine matched pairs without defect or previous surgery (mean age, 78.4 years; range, 60-97 years; three female and six male pairs). Femoral neck densitometry to determine bone mineral density found that all specimens except two were osteopenic or osteoporotic. Specimens in each pair were assigned to allograft or turndown reconstruction. The constructs were mounted on a load frame and differential variable reluctance transducers were applied to measure deformation. Specimens were preconditioned and then loaded axially. Tensile force and proximal and distal construct deformation were measured at clinical failure, defined as 10 mm of displacement, and at ultimate failure, defined as failure of the reconstruction. Failure mechanism was recorded. RESULTS: Tensile strength at time zero was higher in the allograft versus the turndown construct at clinical failure (156.9 ± 29.7 N versus 107.2 ± 20.0 N, respectively; mean difference, -49.7 N; 95% CI, -66.3 to -33.0 N; p < 0.001) and at ultimate failure (290.9 ± 83.2 N versus 140.7 ± 43.5 N, respectively; mean difference, -150.2 N; 95% CI, -202.9 to -97.6 N; p < 0.001). Distal construct deformation was lower in the turndown versus the allograft construct at clinical failure (1.6 ± 1.0 mm versus 4.7 ± 0.7 mm medially and 2.2 ± 1.0 mm versus 4.8 ± 1.1 mm laterally; p < 0.001). Semitendinosus allograft failure occurred via calcaneal bone bridge fracture in eight of nine specimens. All myofascial turndowns failed via suture pullout through the fascial tissue at its insertion. CONCLUSION: In this comparative biomechanical study, dual semitendinosus allograft reconstruction showed greater tensile strength and construct deformation compared with myofascial turndown in a cadaveric model of large Achilles tendon defects. CLINICAL RELEVANCE: Further study of dual semitendinosus allograft for treatment of severe Achilles tendon defects with cyclic loading and investigation of clinical results will better elucidate the clinical utility and indications for this technique.