Effects of Parallax and Distortion in Total Ankle Arthroplasty.

BACKGROUND: Surgeons rely on intraoperative fluoroscopy to assist in placement of implant components during total ankle arthroplasty (TAA). Parallax alters the direction of an object when viewed from two different points, resulting in image distortion. The purpose of this study was to evaluate parallax/distortion in intraoperative fluoroscopic images during TAA. METHODS: A retrospective review of all TAAs performed by two surgeons (R.W.M. and B.S.) from August 2019 to April 2023 were reviewed. Intraoperative fluoroscopic anteroposterior (AP) ankle views were evaluated for any obvious parallax image distortion. Cases with obvious parallax distortion were included for angular evaluation of AP intraoperative fluoroscopic and first postoperative plain films. The tibia was marked at 2-centimeter intervals to create zones from the proximal stem of the implant. The anatomical axis of the tibia (AAT) was drawn at the mid-diaphysis. The anatomic lateral distal tibial angle (aLDTA) and anatomic axis deviation (AAD) were measured for each zone. RESULTS: A total of 22 TAAs were performed during the study period. Four cases were excluded due to inadequate imaging, leaving a total of 18 TAAs for review. We found 6 of 18 (33.3%) cases had obvious parallax distortion. We found the average aLDTA was 90.9° (84°-101°). At the most proximal tibial zone, the average aLDTA was 94° (91°-101°). We found the average AAD was 4.7 (0.5-17.2) mm. The AAD ranged from 0.5 to 17.2 mm lateral to 0.8 to 8.2 mm medial. Postoperative plain film radiographs displayed a normal aLDTA and an AAT centered within the ankle joint. CONCLUSION: Parallax can distort the appearance of the tibia on fluoroscopic images. Deviation from the normal aLDTA and anatomical axis should be anticipated. Surgeons should be aware of the potential impact of parallax and ways to mitigate these effects.

Parallax and Distortion in Fluoroscopy Units.

BACKGROUND: Parallax is an imaging phenomenon where an object appears to be at different positions when viewed from different angles. Distortion can occur secondary to internal fluoroscopic, or external environmental, factors. Fluoroscopy is a vital tool to assist surgeons intraoperatively. However, parallax and distortion can lead to inaccuracy, potentially leading to incorrect surgical decisions. The purpose of this study was to investigate the prevalence of parallax/distortion in large fluoroscopy units at a level-1 trauma center. METHODS: Two types of C-arm models were evaluated, including (1) round image intensifiers, and (2) flat plate detectors (FPD). A square plexiglass grid with embedded wire at ½-in intervals was created, with a round metal washer secured centrally. The grid was placed 16 in from the image intensifier. A metal ball bearing (BB) was secured to the center of the x-ray tube. Fluoroscopic images were obtained until the BB and washer were "center-center." A straight blade served as a fiducial marker to ensure there was no off-axis angulation. Standard anterior-posterior and lateral views were obtained. External factors were considered, tested, and limited. Images were printed and the patterns of parallax/distortion were identified. RESULTS: All 11/11 (100%) of fluoroscopy units had some degree of parallax and/or distortion. We noted 3 different patterns, including sigmoidal, converging, and diverging. The FPD units had less apparent distortion overall; however, two-thirds (66%) were off-axis in the x- and y-axes in relation to the fiducial marker. CONCLUSION: All fluoroscopy units had varying degrees and patterns of parallax/distortion. We noted less overall distortion in FPDs. However, some of these units may produce images that are off-axis. This research has important implications for improving the accuracy of intraoperative fluoroscopy. Musculoskeletal surgeons should understand the limitations of fluoroscopy and how to combat parallax distortion to improve surgical outcomes and reduce patient morbidity. LEVEL OF EVIDENCE: Level V.

Anatomic Description of the Calcaneocuboid Joint: Implications for Staple Fixation.

Understanding the anatomy of the calcaneocuboid (CCJ) remains essential when selecting staple fixation to optimize osseous purchase during rearfoot procedures. This anatomic study quantitatively describes the CCJ in relation to staple fixation sites. The calcaneus and cuboid from 10 cadavers were dissected. Widths at 5 mm and 10 mm increments away from the joint were measured in dorsal, midline, and plantar thirds of each bone. The widths between each position's 5 mm and 10 mm increments were compared using the Student's t test. The widths among the positions at both distances were compared using an ANOVA then post hoc testing. Statistical significance was set at p ≤ 0.05. The middle (23 ± 3 mm) and plantar third (18 ± 3 mm) of the calcaneus at the 10 mm interval was greater than the 5 mm interval (p = .04). At 5 mm distal to the CCJ, the dorsal third of the cuboid maintained a statistically significant greater width than the plantar third (p = .02). The 5 mm (p = .001) and 10 mm (p = .005) dorsal calcaneus widths as well as the 5 mm (p = .003) and 10 mm (p = .007) middle calcaneus widths were significantly greater than the plantar widths. This investigation supports the use of 20 mm staple 10 mm away from the CCJ in dorsal and midline orientations. Care should be taken when placing a plantar staple within 10 mm proximal to the CCJ as the legs may extend beyond the medial cortex compared to dorsal and midline placements.

Correlation of Lisfranc Injuries With Regional Bone Density.

Lisfranc injuries present a challenge due to their ubiquity though frequent missed diagnoses. A paucity of data exists associating the contribution of bone density to injury type. This investigation compares the regional bone density between Lisfranc injury types using computed-tomography (CT)-derived Hounsfield units. A retrospective chart review identified patients with gross ligamentous and avulsion-type Lisfranc injuries determined by CT examination of the second metatarsal base and medial cuneiform. Regional bone density was assessed by averaging the Hounsfield units of the first metatarsal base, navicular, cuboid, calcaneus, and talus between 2 reviewers. Density was compared between injury type, isolated concomitant forefoot, and mid/hindfoot fractures. One hundred thirty-four patients were separated into avulsion (n = 85) and ligamentous (n = 49) groups. No statistically significant difference in patient body mass index, age, smoking status, or Quenu and Kuss injury pattern was observed between groups. The regional bone density of the cuboid (p = .03) and talus (p = .04) was greater in the ligamentous group. Lower extremity concomitant mid/hindfoot fracture patients exhibited greater regional bone density in the ligamentous group in all assessed bones (p ≤ .04) except the calcaneus. Ligamentous injuries of the Lisfranc complex are associated with increased regional bone density among patients sustaining concomitant mid/hindfoot fractures. This study expands the utility of regional bone density analysis in foot and ankle trauma.

CMS Open Payments Database Analysis of Industry Payments for Foot and Ankle Surgery Research.

With decreasing federal funding, the role of industry in supporting medical investigations continues to grow. To increase transparency between physicians and industry, the Centers for Medicare and Medicaid Services introduced the Open Payments Program, providing a searchable database of physician payments from entities including medical device companies. This study describes industry research payments and trends among foot and ankle surgeons. Research Payment Data among foot and ankle surgeons from the Open Payments Database was reviewed from 2013 through 2020. Payment year, value, type, and physician name were collected, and descriptive statistics were presented. Linear regression assessed trends in the number and value of payments. Analysis of variance and subsequent post hoc testing assessed differences in mean payment value. A p value of ≤.05 was considered statistically significant. Overall, 10,872 payments totaling $69,595,393.10 among 446 foot and ankle surgeons were analyzed. No statistically significant increase in number of physicians, payments, or mean payment value per physician was observed from 2013 through 2020. However, the average value of payments in 2019 and 2020 was greater than 2015 and 2017 (p ≤ .05). The top 50 physicians according to cumulative payment value received $54,696,623.10 with 9427 (86.7%) cash and cash-equivalent payments representing the most common payment type overall. Industry continues to provide financial support to foot and ankle surgery research. Results of this investigation spur future studies to examine the relationship between payments and positive results reported by lead investigators in published research.

Self-Reported Conflicts of Interests and Financial Disclosures in The Journal of Foot & Ankle Surgery: A Systematic Review.

Industry, academia, and professional societies provide financial and in-kind support for physician-lead research; however, the prevalence and role remain unreported. From consultancies to leadership positions, foot and ankle surgeons receive a spectrum of support. To provide transparency between these relationships and published outcomes, journals report conflicts of interest (COI) and financial disclosures (FD). This investigation analyzes self-reported COIs and FDs in The Journal of Foot & Ankle Surgery (JFAS)®. A systematic review of manuscripts reporting COIs and FDs from the January 2008 through November 2020 issues of JFAS was conducted. Editorials, commentaries, and technique articles were excluded. Disclosure type, level of evidence, and affiliated country of authorship were collected. Trends and proportions of articles with disclosures were analyzed from before a published Open Payments Database (OPD) (2008-2013) through 2020. Among 2699 articles, 382 reported a COI or FD. The number of manuscripts with COIs and FDs increased since 2008 (p < .001). The proportion of articles with COIs or FDs was greater after the OPD was published compared to prior (p < .001). Overall, 86.35% of reported COIs were industry related while 37.09% of FDs were hospital, university, or state sponsor affiliated. International authorship was a negative predictor of COIs and FDs (p < .001). Level 3 and 4 studies were 4.60 (95%CI [0.85-24.85]) and 5.56 (95%CI [1.04-29.72]) times as likely to have self-reported a COI compared to level 1 studies, respectively. Level 2 and 5 studies were 0.33 (95%CI [0.04-3.16]) and 0.36 (95%CI [0.04-3.13]) times as likely to have self-reported a FD compared to level 1 studies, respectively. This investigation found an increase in the proportion of manuscripts with self-reported COIs and FDs since first documented in JFAS. These findings illustrate the ubiquity of author industry involvement, though future studies may examine the relevancy of these roles to published research.

Is advanced imaging necessary before surgical repair.

Posterior tibial tendon dysfunction (tendinitis, tendinosis, or rupture) and adult acquired flatfoot deformity can manifest with a wide array of bony and soft tissue abnormalities visible on plain radiographs, ultrasound, and magnetic resonance imaging. Imaging abnormalities include various combinations of malalignment, anatomic variants, and enthesopathic and tendinopathic changes. A thorough understanding of differences between anatomic and pathologic presentations of structures in various imaging modalities is an essential tool for clinical and surgical planning.

Triple arthrodesis for adult acquired flatfoot.

The primary goal of triple arthrodesis for stage III and IV adult acquired flatfoot is to obtain a well-aligned plantigrade foot that will support the ankle in optimal alignment. Ancillary procedures including posterior muscle group lengthening, medial displacement calcaneal osteotomy, medial column stabilization, peroneus brevis tenotomy, or transfer and harvest of regional bone graft are often necessary to achieve adequate realignment. Image intensification is helpful in confirming optimal realignment before fixation. Results of triple arthrodesis are enhanced with adequate preparation of joint surfaces, bone graft/orthobiologics, 2-point fixation of all 3 tritarsal joints, and a vertical heel position.

Surgical considerations for the neglected or chronic Achilles tendon rupture: a combined technique for reconstruction.

The Achilles tendon is among the most commonly injured tendons in the human body. The most common reason for delayed treatment is a missed diagnosis or a deficiency in presentation. The neglected or chronically ruptured Achilles tendon presents a unique treatment challenge. The surgical approach varies greatly depending on the extent of degeneration and the resultant gap between the opposing tendon ends. Most surgeons have recommended the use of a tendon transfer or augmentation to strengthen the Achilles tendon repair. The following technique uses a flexor hallucis longus tendon transfer with gastrocnemius aponeurosis turndown flap augmentation. This technique has been commonly performed by us with success.

Surgical approach for combined ankle and subtalar joint chronic mechanical instability.

Combined ankle and subtalar joint instability can lead to severe disability of the lower extremity. Multiple procedures have been described for hindfoot and ankle instability, including anatomic and non-anatomic reconstructions. The authors present their technique consisting of a free autogenous split peroneus longus tendon graft combined with a modified Brostrom-Gould repair.

Technical considerations for surgical intervention of Jones fractures.

Jones fractures are a common injury treated by foot and ankle surgeons. Surgical intervention is recommended because of the high rate of delayed union, nonunion, and repeat fracture, when treated conservatively. Percutaneous intramedullary screw fixation is commonly used in the treatment of these fractures. We present techniques that can increase the surgical efficiency and decrease the complications associated with percutaneous delivery of internal fixation.

Role of body mass index in acute charcot neuroarthropathy.

Obesity has been posited as a predictor for the development of Charcot neuroarthropathy, a severe form of degenerative joint disease associated with peripheral neuropathy and diabetes mellitus. The present case-control study investigated the relationship between elevated (overweight and obese) body mass index and acute Charcot neuroarthropathy in a diabetic population. The final data set consisted of 49 patients, 20 (40.82%) of whom had Charcot foot and 29 (59.18%) who served as controls. In the present investigation, no statistically significant association was found between an elevated body mass index and the development of acute Charcot neuroarthropathy involving the foot.

Factors affecting healing of ankle fractures.

Ankle fractures have been widely described in orthopedic and podiatric studies. These injuries have been associated with significant patient morbidity, infection, malunion, nonunion, and arthritis. Avoiding complications and optimizing outcomes demands an awareness of the factors affecting the healing of ankle fractures. The prognosis of surgical treatment of these injuries has varied according to patient factors or injury severity, or a combination. Cigarette smoking, obesity, and diabetes are some of the factors linked to the prognosis of ankle fractures. We conducted a retrospective cohort study of 58 patients treated for an ankle fracture at a single center. The objective of the present study was to comprehensively evaluate the factors affecting the clinical outcome of surgically treated ankle fractures.

Venous thromboembolism and foot and ankle surgery: current updates 2012.

Significant patient morbidity and mortality is associated with the development of venous thromboembolism (VTE) following orthopedic surgery. The majority of the literature supports proper prophylaxis following major orthopedic surgery involving hip and knee procedures. Foot and ankle surgery, however, is starkly contrasted because of the lack of recommendations. This article provides a comprehensive overview of the risk factors and incidence of VTE in foot and ankle surgery while also outlining the newest literature guidelines for prophylaxis.

An anatomic safe zone for posterior ankle arthroscopy: a cadaver study.

Posterior ankle arthroscopy has traditionally been associated with concern for injury to the posterior tibial nerve and vessels, and this concern is greatest when the patient is positioned supine. Positioning the patient prone could be a safer method for posterior ankle arthroscopy. The purpose of this cadaver study was to determine the anatomic safe zone devoid of vital structures relative to the posteromedial and posterolateral arthroscopic portals created. In addition, exposure of the posterior ankle was evaluated by direct visualization and fluoroscopy to determine the relative utility of these portals. Based on our findings, which are consistent with other previously reported results, we believe that a wide range of ankle pathology can be suited to treatment by means of posterior arthroscopy with the patient in the prone position.

Incidence of talar dome lesions with concomitant peroneal tendon pathologic features: a magnetic resonance imaging evaluation.

Few studies have evaluated the incidence of talar dome lesions and injuries to the peroneal tendons occurring concomitantly. The purpose of our research was to evaluate the incidence of osteochondral lesions of the talus (OLT) with peroneal tendon pathologic features according to the magnetic resonance imaging (MRI) findings. A database search was conducted in the Department of Radiology at the Western Pennsylvania Hospital and Forbes Regional Campus for all MRI examinations ordered by attending physicians of the Department of Foot and Ankle Surgery from 2008 to 2010. A total of 810 MRI reports were reviewed, of which 198 contained a diagnosis of peroneal tendon pathologic features (e.g., tenosynovitis, split tears) or OLT (i.e., chondral, osteochondral, subchondral edema, cystic changes), or both. MRI scans were then reviewed to confirm the report findings and findings not identified in the report. A total of 76 patients were identified as having an OLT. Of these 76 patients, 49 had associated peroneal tendon pathologic features. MRI evaluation revealed that 49 (65.3%) of the 76 patients with a talar dome lesion had concomitant peroneal pathologic features. Talar dome lesions with concomitant tears/tendinopathy of the peroneus brevis were associated in 14.6%. The incidence of an OLT with tears/tenosynovitis of the peroneus longus was 10.6%, because tears/tendinopathy of both peroneal tendons was present in 18.6%. Tenosynovitis of the brevis and longus were seen in 21.3% of those with an OLT. Our findings suggest the need for an increased level of suspicion for injuries to the lateral ankle ligaments, peroneal tendon complex, and ankle joint when evaluating a patient with ankle instability and chronic pain.

Deep vein thrombosis after bunionectomy: a case report of two genetic mutations.

Deep venous thrombosis after foot and ankle surgery is a serious complication that can have potentially life-threatening complications, such as pulmonary embolus. Genetic mutations have been reported in the published data to cause an increased risk of developing deep vein thrombosis. Two such genetic mutations are the methylenetetrahydrofolate reductase gene variant C677T and the 4G/5G polymorphism of the plasminogen activator inhibitor gene. This case report presents a female patient who developed a postoperative deep vein thrombosis after hallux valgus reconstruction. A hypercoagulable panel revealed the 2 mentioned genetic mutations. We hope this case study will highlight the importance of ascertaining all patient risk factors and the relation to perioperative deep vein thrombosis prophylaxis.

The hematoma block: a simple, effective technique for closed reduction of ankle fracture dislocations.

Management of a dislocated ankle fracture can be challenging because of instability of the ankle mortise, a compromised soft tissue envelope, and the potential neurovascular compromise. Every effort should be made to quickly and efficiently relocate the disrupted ankle joint. Within the emergency department setting, narcotics and benzodiazepines can be used to sedate the patient before attempting closed reduction. The combination of narcotics and benzodiazepines provides relief of pain and muscle guarding; however, it conveys a risk of seizure as well as respiratory arrest. An alternative to conscious sedation is the hematoma block, or an intra-articular local anesthetic injection in the ankle joint and the associated fracture hematoma. The hematoma block offers a comparable amount of analgesia to conscious sedation without the additional cardiovascular risk, hospital cost, and procedure time.