Discrepancies Between Intraoperative and Postoperative Ankle Motion Measured for Anterior-Approach Total Ankle Arthroplasty.

BACKGROUND: Although intraoperative ankle motion serves as a foundational reference for anticipated motion after surgery and guides the addition of procedures to enhance ankle motion in total ankle arthroplasty (TAA), the relationship between intraoperative and postoperative ankle motion remains unclear. This study aimed to investigate the discrepancy between intraoperative and postoperative ankle range of motion (ROM) following TAAs using the anterior-approach, fixed-bearing systems. METHODS: This study retrospectively reviewed 67 patients (67 ankles) who underwent primary TAA at a single institution. Three different types of anterior-approach, fixed-bearing TAA systems were included. Intraoperative fluoroscopy was used to document the maximal dorsiflexion and plantar flexion at the end of the case. Standardized weightbearing maximum dorsiflexion and plantar flexion sagittal radiographs were obtained pre- and postoperatively, following a previously described method. The motion between 3 different time points (preoperative, intraoperative, and postoperative [mean 11.4 months]) was compared using pairwise t tests, and their differences were quantified. RESULTS: The mean total tibiotalar ROM was 38.1 degrees (SD 7.8) intraoperatively, and the postoperative total tibiotalar ROM was 24.2 degrees (SD 9.7) (P < .001), indicating that a mean of 65.3% (SD 26.7) of the intraoperative motion was maintained postoperatively. Intraoperative dorsiflexion (mean 11.6 [SD 4.5] degrees) showed no evidence of difference from postoperative dorsiflexion (mean 11.4 [SD 5.8] degrees, P > .99), indicating that a median of 95.6% (interquartile range: 66.2-112) of the intraoperative maximum dorsiflexion was maintained postoperatively. However, there was a significant difference between intraoperative plantarflexion (mean 26.4 [SD 6.3]) and postoperative plantarflexion (12.8 [SD 6.9] degrees, P < .001), indicating a mean 50.6% (SD 29.6) of intraoperative motion maintained in the postoperative assessment. There was an improvement of 2.5 degrees in the total tibiotalar ROM following TAA with statistical significance (P < .043). CONCLUSION: This study revealed a significant difference between intraoperative ankle ROM and ankle ROM approximately 1 year after anterior-approach, fixed-bearing TAA, mainly due to plantarflexion motion restriction. Minimal difference in dorsiflexion suggests the importance of achieving the desired postoperative dorsiflexion motion during the surgery using the best possible adjunct procedures. LEVEL OF EVIDENCE: Level IV, case series.

Early Radiographic and Clinical Outcomes of a Novel, Fixed-Bearing Fourth-Generation Total Ankle Replacement System.

BACKGROUND: The Cadence Total Ankle System is a 2-component, fixed-bearing fourth-generation total ankle arthroplasty (TAA) system that was introduced for clinical use in 2016. The purpose of this study was to report non-inventor, non-industry funded survivorship, radiographic and clinical outcomes, and early complications following use of this implant at a minimum of 2 years. METHODS: This single-center retrospective study included patients who underwent TAA by 2 surgeons with this novel fixed-bearing system between January 2017 and September 2018. Forty-eight patients were evaluated at an average of 33.6 months. Radiographic outcomes included preoperative and postoperative tibiotalar angle on anteroposterior radiographs of the ankle, sagittal tibial angle (STA) on lateral radiographs of the ankle, and periprosthetic lucency formation and location. Revision and reoperation data were collected, and patient-reported outcomes were assessed using Patient Reported Outcomes Measurement Information System (PROMIS). Subgroup analysis assessed associations between preoperative deformity, postoperative implant alignment, PROMIS scores, and periprosthetic lucency formation. RESULTS: Survivorship of implant was 93.7%, with 3 revisions, 1 due to infection and 2 due to loosening of the implant (1 tibial and 1 talar component). Three patients had reoperations (6.3%): 2 for superficial infection and 1 for gutter debridement due to medial gutter impingement. Fifteen patients (35.8%) developed periprosthetic lucencies, all on the tibial side. PROMIS scores improved after surgery in all domains except Depression. Patients with significant postoperative periprosthetic lucency had worse postoperative PROMIS Physical function scores than patients without lucency (P < .05). CONCLUSION: This study demonstrated excellent minimum 2-year clinical and radiographic outcomes and low revision and reoperation rates of this new fourth-generation TAA system. Future studies with longer follow-up, especially on patients with periprosthetic lucency, are necessary to investigate the long-term complications and understand the long-term functional and radiographic outcomes of this implant.

Orthosis and Foot Structure Affect the Fifth Metatarsal Principal Strains During Simulated Level Walking.

BACKGROUND: Fractures of the proximal fifth metatarsal bone are common injuries in elite athletes and are associated with high rates of delayed union and nonunion. Structural features of the foot may increase fracture risk in some individuals, emphasizing the need for intervention strategies to prevent fracture. Although orthotic devices have shown promise in reducing fractures of the fifth metatarsal bone, the effect of orthosis on fifth metatarsal strains is not well understood. PURPOSE: To quantify the effects of different foot orthotic constructs on principal tensile strains in the proximal fifth metatarsal bone during cadaveric simulations of level walking. An additional purpose was to investigate the relationships between structural features of the foot and corresponding strains on the fifth metatarsal bone during level walking. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 10 midtibial cadaveric specimens were attached to a 6 degrees of freedom robotic gait simulator. Strain gauges were placed at the metaphyseal-diaphyseal junction (zone II) and the proximal diaphysis (zone III) during level walking simulations using 11 different foot orthotic configurations. Images of each specimen were used to measure structural features of the foot in an axially loaded position. The peak tensile strains were measured and reported relative to the sneaker-only condition for each orthotic condition and orthotic-specific association between structural features and principal strains of both zones. RESULTS: In total, 2 of the 11 orthotic conditions significantly reduced strain relative to the sneaker-only condition in zone II. Further, 6 orthotic conditions significantly reduced strain relative to the sneaker-only condition in zone III. Increased zone II principal strain incurred during level walking in the sneaker-only condition showed a significant association with increases in the Meary's angle. Changes in zone III principal strain relative to the sneaker-only condition were significantly associated with increases in the Meary's angle and fourth-fifth intermetatarsal angle. CONCLUSION: The use of orthotic devices reduced principal strain relative to the condition of a sneaker without any orthosis in zone II and zone III. The ability to reduce strain relative to the sneaker-only condition in zone III was indicated by increasing values of the Meary's angle and levels of the fourth-fifth intermetatarsal angle. CLINICAL RELEVANCE: Clinicians can use characteristics of foot structure to determine the proper foot orthosis to potentially reduce stress fracture risk in high-risk individuals.

Finite Element Modeling of Planus and Rectus Foot Types for the Study of First Metatarsophalangeal and First Metatarsocuneiform Joint Contact Mechanics.

The foot is a highly complex biomechanical system for which finite element (FE) modeling has been used to evaluate its loading environment. However, there is limited knowledge of first metatarsophalangeal (MTP) and first metatarsocuneiform (MTC) joint contact mechanics. Our goal was to develop a framework for FE modeling of the medial forefoot which could accurately predict experimental measurements of first MTP and first MTC joint loading. Simulations of planus and rectus foot types were conducted for midstance of gait. A custom-built force-controlled cadaveric test-rig was used to derive intracapsular pressure sensor measurements of contact pressure, force, and area during quasi-static loading. The FE model was driven under the same boundary and loading conditions as the cadaver. Mesh sensitivity analyses and best-fit calibrations of moduli for first MTP and first MTC joint cartilage were performed. Consistent with previous experimental research, a lower compressive modulus was best-fit to the first MTP compared to first MTC joint at 10 MPa and 20 MPa, respectively. Mean errors in contact pressures, forces, and areas were 24%, 4%, and 40% at the first MTP joint and 23%, 12%, and 19% at the first MTC joint, respectively. The present developmental framework may provide a basis for future modeling of first MTP and first MTC joint contact mechanics. This study acts as a precursor to validation of realistic physiological loading across gait to investigate joint loading, foot type biomechanics, and surgical interventions of the medial forefoot.

A short single-incision approach for antiglide plate fixation of oblique fractures of the lateral malleolus: a technical tip.

Displaced fractures (> 2 mm) of the lateral malleolus, without medial or syndesmotic injuries, are often the subject of controversy regarding the best treatment option. In the past, these fractures were usually treated conservatively using a cast for 6 to 8 weeks without weightbearing. Currently, most of the patients desire a quick return to their previous activities, what makes surgical treatment a reasonable choice. It has benefits as earlier ankle mobilization and weightbearing. It also restores ankle biomechanics, preventing secondary osteoarthritis. However, postoperative complications with the standard lateral incision exist such as implant discomfort, dehiscence and infection. Minimally invasive techniques have been described to help avoiding these complications. This technical note described a short single-incision approach for the surgical treatment of displaced oblique fibular fractures type AO/OTA 44-B1 with an antiglide plate that presents the advantage of less risk of damaging the soft tissues, periosteal stripping and disturbance of the fracture hematoma.

HALLUX PROXIMAL PHALANX FRACTURE IN ADULTS: AN OVERLOOKED DIAGNOSIS.

OBJECTIVES: To describe the surgical treatment of fractures that involves the hallux interphalangeal joint, current indications and management options. METHODS: we performed a literature review of relevant clinical studies in multiple databases, including PubMed, MedLine and Scopus, from January 1989 to October 2020. RESULTS: There is consensus for surgical treatment of intra-articular fractures with a deviation greater than 2 mm, metadiaphyseal fractures with malrotation and/or malangulation, open fractures and unstable fractures. CONCLUSION: The use of more rigid implants allow alignment maintenance during healing process and lower risk of reduction loss. Valgus deformity and interphalangeal joint osteoarthritis are possible complications that must be avoided. Level of Evidence III, Systematic review of Level III studies.

OBJETIVOS: destacar o tratamento cirúrgico das fraturas que envolvem a articulação interfalangiana do hálux, suas indicações atuais e as opções de tratamento. MÉTODOS: Realizamos uma revisão da literatura de estudos clínicos relevantes em múltiplas bases de dados, incluindo PubMed, MedLine e Scopus, de janeiro de 1989 a outubro de 2020. RESULTADOS: Há consenso para o tratamento cirúrgico de fraturas intra-articulares com desvio superior a 2 mm, fraturas metadiafisárias com má rotação e/ou malangulação, fraturas expostas e fraturas instáveis. CONCLUSÃO: O uso de implantes mais rígidos permite a manutenção do alinhamento durante o processo de consolidação e menor risco de perda da redução. As complicações que devem ser evitadas são a deformidade em valgo e a osteoartrite da articulação interfalangeana. Nível de Evidência III, Revisão sistemática de Estudos de Nível III.

Expanding the horizons of clinical applications of proximal humerus locking plates in the lower extremities: A technical note.

Pre-contoured anatomical locking plates were designed to address the clinical need of fixing small epiphyseal segments with a larger number of screws. Those plates match the contour and shape of a variety of bones allowing for optimal buttress properties. The aim of this manuscript is to highlight the benefits of applying proximal humerus locking plates in the fixation of lower extremity bones. Although designed for the proximal humerus, the low-profile plate shape and anatomic contour also provides versatile use in certain areas of the lower extremity. This technical narrative highlights the versatile and reliable use of this plate for other anatomical areas than the one to which it has been originally conceived.

Intra-articular Transcalcaneal Fracture-Dislocation Associated With Ipsilateral Transtalar Fracture: A Report of a Rare Combination.

The association of ipsilateral talar and calcaneal fractures is an uncommon combination and is typically the result of a high-energy trauma. It is often associated with comminution, marked fracture displacement, and soft-tissue compromise. Obtaining satisfactory clinical and radiographic results is very challenging. Residual deformities, multiple procedures, and limitations are usually the norm. Therefore, studies have suggested that primary arthrodesis may represent the best option of surgical treatment. In this study, we report a case of a 30-year-old male patient with a rare combination of a highly comminuted transcalcaneal fracture-dislocation associated with a talar neck fracture successfully treated with open reduction and internal fixation (ORIF) with an 18-month follow-up. This case demonstrates that even when there are associated fractures of the talus and calcaneus with severe bone loss, ORIF may provide satisfactory outcomes in the short-term postoperative period.Levels of Evidence: Level V: Case report.

SAFE LOCALIZATION FOR PLACEMENT OF PERCUTANEOUS PINS IN THE CALCANEUS.

OBJECTIVE: To determine the areas presenting risk in six zones of the calcaneus, and to quantify the risks of injury to the anatomical structures (artery, vein, nerve and tendon). METHOD: Fifty-three calcanei from cadavers were used, divided into three zones and each subdivided in two areas (upper and lower) by means of a longitudinal line through the calcaneus. The risk of injury to the anatomical structures in relation to each Kirschner wire was determined using a graded system according to the Licht classification. The total risk of injury to the anatomical structures through placement of more than one wire was quantified using the additive law of probabilities and the product law for independent events. RESULTS: The injury risk calculation according to the Licht classification showed that the highest risk of injury to the artery or vein was in zone IA (43%), in relation to injuries to nerves and tendons (13% and 0%, respectively). CONCLUSION: This study made it possible to identify the most vulnerable anatomical structures and quantify the risk of injury to the calcaneus.

Localização segura na colocação dos pinos percutâneos no calcâneo / Safe localization for placement of percutaneous pins in the calcaneus

OBJETIVO: Determinar as áreas de risco em seis zonas do calcanhar e quantificar os riscos de lesão das estruturas anatômicas (artéria, veia, nervo e tendão). MÉTODO: Foram utilizados 53 calcâneos de cadáveres divididos em três zonas e subdivididas em duas áreas, superior e inferior, por meio de uma linha longitudinal do calcâneo. O risco de lesão das estruturas anatômicas em relação a cada fio de Kirschner foi determinado pelo sistema de graduação segundo a classificação de Licht. A quantificação do risco total de lesão das estruturas anatômicas na colocação de mais de um fio foi calculada pela lei aditiva das probabilidades e pela lei do produto para eventos independentes. RESULTADOS: O cálculo dos riscos de lesão, segundo a classificação de Licht, demonstrou que o risco de lesão da artéria ou veia na zona IA é mais expressivo (43%) em relação às lesões de nervo e tendão (13 e 0%, respectivamente). CONCLUSÃO: O estudo permitiu identificar as estruturas anatômicas mais vulneráveis e quantificar o risco de lesão no calcanhar.

OBJECTIVE: To determine the areas presenting risk in six zones of the calcaneus, and to quantify the risks of injury to the anatomical structures (artery, vein, nerve and tendon). METHOD: Fifty-three calcaneus from cadavers were used, divided into three zones and each subdivided in two areas (upper and lower) by means of a longitudinal line through the calcaneus. The risk of injury to the anatomical structures in relation to each Kirschner wire was determined using a graded system according to the Licht classification. The total risk of injury to the anatomical structures through placement of more than one wire was quantified using the additive law of probabilities and the product law for independent events. RESULTS: The injury risk calculation according to the Licht classification showed that the highest risk of injury to the artery or vein was in zone IA (43%), in relation to injuries to nerves and tendons (13% and 0%, respectively). CONCLUSION: This study made it possible to identify the most vulnerable anatomical structures and quantify the risk of injury to the calcaneus.

TIBIAL PLATEAU FRACTURES.

Tibial plateau fractures are joint lesions that require anatomical reduction of joint surface and functional restoration of mechanical axis of a lower limb. Patient profile, soft tissue conditions, presence of associated injuries and the available infrastructure for the treatment all contribute to the decision making about the best treatment for these fractures. High-energy fractures are usually approached in a staged manner respecting the principle of damage control, and are primarily targeted to maintain limb alignment while the resolution unfavorable soft tissue conditions is pending. Low-energy trauma can be managed on a singlestage basis, provided soft tissues are not an adverse factor, with open reduction and internal fixation. Stable fixation and early painless joint movement are related to a better prognosis. New developments as locked plates, bone replacements, intraoperative 3D imaging are promising and will certainly contribute for less invasive procedures and better outcomes.

Fraturas do planalto tibial / Tibial plateau fractures

As fraturas do planalto tibial são lesões articulares cujos princípios de tratamento envolvem a redução anatômica da superfície articular e a restauração funcional do eixo mecânico do membro inferior. Contribuem para a tomada de decisões no tratamento dessas fraturas o perfil do paciente, as condições do envelope de tecidos moles, a existência de outros traumatismos associados e a infraestrutura disponível para abordagens cirúrgicas. Para as fraturas de alta energia, o tratamento estagiado, seguindo o princípio do controle de danos, tem como prioridade a manutenção do alinhamento do membro enquanto se aguarda a resolução das más condições de tecidos moles. Já nos traumas de baixa energia, desde que os tecidos moles não sejam um fator adverso, o tratamento deve ser realizado em tempo único, com osteossíntese definitiva. Fixação estável e movimento precoce são variáveis diretamente relacionadas com os melhores prognósticos. Desenvolvimentos recentes, como os implantes com estabilidade angular, substitutos ósseos e imagens tridimensionais para controle intraoperatório, deverão contribuir para cirurgias menos invasivas e melhores resultados.

Tibial plateau fractures are joint lesions that require anatomical reduction of joint surface and functional restoration of mechanical axis of a lower limb. Patient profile, soft tissue conditions, presence of associated injuries and the available infrastructure for the treatment all contribute to the decision making about the best treatment for these fractures. High-energy fractures are usually approached in a staged manner respecting the principle of damage control, and are primarily targeted to maintain limb alignment while the resolution unfavorable soft tissue conditions is pending. Low-energy trauma can be managed on a single-stage basis, provided soft tissues are not an adverse factor, with open reduction and internal f-ixation. Stable fixation and early painless joint movement are related to a better prognosis. New developments as locked plates, bone replacements, intraoperative 3D imaging are promising and will certainly contribute for less invasive procedures and better outcomes.

Fraturas ocultas do platô tibial: estudo de três casos por ressonância magnética / Occult fractures of the tibial plateau: report of three cases by magnetic resonance imageing

Os autores relatam três casos de fratura oculta do platô tibial evidenciados pelos exames de ressonância magnética do joelho, os quais foram solicitados quando, na presença de um trauma agudo de joelho, o exame clínico foi dificultado pela dor e edema, com radiografias simples negativas.