The Influence of Talar Displacement on Articular Contact Mechanics: A 3D Finite Element Analysis Study Using Weightbearing Computed Tomography.

BACKGROUND: Talar displacement is considered the main predictive factor for poor outcomes and the development of post-traumatic osteoarthritis after ankle fractures. Isolated lateral talar translation, as previously studied by Ramsey and Hamilton using carbon powder imprinting, does not fully replicate the multidirectional joint subluxations seen in ankle fractures. The purpose of this study was to analyze the influence of multiple uniplanar talar displacements on tibiotalar contact mechanics utilizing weightbearing computed tomography (WBCT) and finite element analysis (FEA). METHODS: Nineteen subjects (mean age = 37.6 years) with no history of ankle surgery or injury having undergone WBCT arthrogram (n = 1) and WBCT without arthrogram (n = 18) were included. Segmentation of the WBCT images into 3D simulated models of bone and cartilage was performed. Three-dimensional (3D) multiple uniplanar talar displacements were simulated to investigate the respective influence of various uniaxial displacements (including lateral translation, anteroposterior translation, varus-valgus angulation, and external rotation) on the tibiotalar contact mechanics using FEA. Tibiotalar peak contact stress and contact area were modeled for each displacement and its gradations. RESULTS: Our modeling demonstrated that peak contact stress of the talus and tibia increased, whereas contact area decreased, with incremental displacement in all tested directions. Contact stress maps of the talus and tibia were computed for each displacement demonstrating unique patterns of pressure derangement. One millimeter of lateral translation resulted in 14% increase of peak talar contact pressure and a 3% decrease in contact area. CONCLUSION: Our model predicted that with lateral talar translation, there is less noticeable change in tibiotalar contact area compared with prior studies whereas external rotation greater than 12 degrees had the largest effect on peak contact stress predictions. LEVEL OF EVIDENCE: Level V, computational simulation study.

The role of imaging in the diagnosis, staging, and management of the osteochondral lesions of the talus.

Osteochondral lesions of the talus (OLT) represent an abnormality of the articular cartilage and sub-chondral bone. The abnormality is typically associated with trauma though the exact aetiology remains unknown. Multiple staging systems have been developed to classify the abnormality and management can vary from conservative treatment to different surgical options. Early diagnosis is essential for optimal outcome and all imaging modalities have a role to play in patient management. The aim of this article is to review the pathology, classification, multimodality imaging appearances of OLT, and how the imaging affects patient management.

Bilateral Os Trigonum Fracture Treated With Simultaneous Posterior Ankle Arthroscopy.

This is a case report of a 21-year-old female undergraduate student who sustained bilateral ankle injuries while jumping from a moving van wearing 3-inch high heel shoes. Upon initial presentation, her injury was treated conservatively as an acute bilateral ankle sprain for 6 weeks. However, the patient reported no improvement of pain and remained unable to self-ambulate. Bilateral MRI and CT scans of both ankles demonstrated bilateral os trigonum fractures. She underwent bilateral posterior ankle arthroscopic débridement of both os trigonum. At the postoperative 36-month follow-up, the patient reported notable improvement of all functional outcomes (36-item Short Form survey and Foot and Ankle Ability Measure), reported return to the same level of sports activities, and experienced no pain (visual analog scale) on either ankle. This is the first report in the literature of bilateral os trigonum fracture treated with simultaneous posterior ankle arthroscopic débridement.

Primary total talus arthroplasty for Hawkins type IV talar neck fracture dislocation.

A woman in her 40s was involved in a motor vehicle collision and sustained a closed Hawkins type IV talar neck fracture dislocation. The injury was treated with reduction, percutaneous pinning and spanning external fixation, followed by definitive treatment with total talus arthroplasty (TTA) 2 months following injury. This is a unique example of definitive management for a severe talar neck fracture dislocation with arthroplasty in the subacute setting. TTA is perhaps a primary option for these injuries at high risk for avascular necrosis, non-union, malunion and post-traumatic arthritis.

Os Trigonum Syndrome: A Cause of Posterior Ankle Pain.

BACKGROUND: Os trigonum syndrome represents a cause of posterior ankle pain that is predominantly seen in athletes. The os trigonum ossicle forms from a secondary ossification center of the talus and is located at its posterior aspect in an interval between the posterior lip of the tibial plafond and calcaneus. The os trigonum ossicle is often an incidental finding and asymptomatic. However, repetitive plantarflexion and push-off maneuvers can cause symptoms and lead a patient to pursue orthopedic care. MATERIALS AND METHODS: A review of the literature was conducted using the PubMed search engine with the following keywords: "os trigonum", "os trigonum ossicle", "os trigonum syndrome", "posterior ankle impingement", and "Stieda process". RESULTS: The pertinent anatomy, clinical presentation, diagnostic evaluation, and treatment of os trigonum syndrome were reviewed in the literature and are extensively discussed in this article. CONCLUSION: Os trigonum syndrome represents a potential cause of posterior ankle pain that needs thorough evaluation regarding history, physical examination, and imaging. Once diagnosed, treatment ranges from conservative to surgical interventions depending on surgeon preference and specific case presentation. [Orthopedics. 2024;47(2):e67-e72.].

Talar neck rotation angle in adults with clubfoot deformity: Observed values and intra- and inter-observer reliability using weightbearing CT.

INTRODUCTION: Adults presenting with symptomatic clubfoot represent a challenging cohort of patients. An appreciation of the location and degree of deformities is essential for management. Talar anatomy is often abnormal with varus within the talar neck, however, there are few reproducible methods which quantify talar neck deformity in adults. We describe a technique of assessing talar neck deformity, and report on observed values and intra- / inter-observer reliability. METHODS: This was a single-centre, retrospective study including 96 feet from 56 adult patients with clubfeet (82 feet had clubfoot deformity, 14 were normal). Mean age was 34.3 ± 16.9 years and 31 (55.3%) were male. Weight-bearing CT scans captured as part of routine clinical care were analysed. Image reformats were oriented parallel to the long axis of the talus in the sagittal plane. In the corresponding axial plane two lines were drawn (on separate slices): 1) a line perpendicular to the intermalleolar axis, 2) a line connecting the midpoints of the talar head and narrowest part of the talar neck. The talar neck rotation angle (TNR angle) was the angle formed between these lines. Intraclass correlation coefficients (ICC) were performed for intra- and inter-observer reliability. RESULTS: Mean TNR angle in clubfeet was 27.6 ± 12.2 degrees (95%CI = 25.0 to 30.2 degrees). Mean TNR angle in normal feet was 18.7 ± 5.1 degrees (95%CI = 16.0 to 21.4 degrees) (p < 0.001). The ICC for clubfeet was 0.944 (95%CI = 0.913 to 0.964) for intra-observer agreement, and 0.896 (95%CI = 0.837 to 0.932) for inter-observer agreement. CONCLUSION: This measurement technique demonstrated excellent intra- and inter-observer agreement. It also demonstrated that compared to normal feet, clubfeet had about 9 degrees of increased varus angulation of the talar neck. This technique and data may be used for future research into clubfoot deformity and in planning treatment. LEVEL OF CLINICAL EVIDENCE: 3.

Outcomes following total ankle total talus replacement: A systematic review.

BACKGROUND: Prosthetic substitution of the talus presents a significant challenge to the foot and ankle surgeon. The shear and compressive forces on the talus and its tenuous blood supply lead to high rates of avascular necrosis and eventual talar collapse. The purpose of this systematic review is to evaluate whether total ankle total talus replacement (TATTR) leads to improved clinical and radiographic outcomes with appropriate safety metrics in patients with a history of avascular necrosis or significant trauma. METHODS: We searched the concepts of talus, prosthesis, and arthroplasty in MEDLINE (PubMed), Embase (Elsevier), CINAHL Complete (EBSCOhost), and Scopus (Elsevier) from the database's inception through March 9, 2023. Inclusion Criteria were 1) previous trauma to the talus, 2) post-traumatic arthritis to the tibiotalar joint, 3) avascular necrosis of talus, 4) multiple failed prior interventions, 5) degenerative osteoarthritis to the tibiotalar joint, and 6) inflammatory arthropathy to tibiotalar joint. Patients less than 18 years of age and manuscripts in non-English languages were excluded. RESULTS: Of the 7625 references, 16 studies met the inclusion criteria, yielding data from 136 patients (139 ankles). The studies varied in design, with case reports and retrospective case series being predominant. The overall weighted average modified Coleman Methodology Score (mCMS) was 70.4 out of 100, indicating moderate flaws in study design that may be subject to various forms of bias and possible confounders. Demographics showed a diverse range of etiologies, with alumina ceramic being the primary prosthesis material. Functional scores demonstrated improvements in dorsiflexion and plantarflexion, although patient-reported outcome measures (PROs) were inconsistently reported. Complications included fractures, heterotopic ossification, prolonged wound healing, and infections. Revision details were sparsely reported. CONCLUSION: TATTR is a promising treatment modality for improving short-term functional outcomes for patients with avascular necrosis or trauma-related issues. However, this systematic review underscores the need for standardized reporting, longer-term follow-ups, and further research to establish the procedure's efficacy and safety, particularly in comparison to other treatment modalities. LEVEL OF EVIDENCE: III, Systematic Review of Level IV Studies.

Arthroscopy-assisted reduction and simultaneous robotic-assisted screw placement in the treatment of fractures of the posterior talar process.

PURPOSE: A fracture of the posterior talar process is easily missed because of its hidden position. Inappropriate treatment is likely to result in complications, such as nonunion of the fracture and traumatic arthritis. This study evaluated the outcomes of arthroscopy-assisted reduction combined with robotic-assisted screw placement in the treatment of fractures of the posterior talar process. METHODS: The clinical data for nine patients who underwent surgical treatment of a fracture of the posterior talar process at our institution between September 2017 and January 2021 were retrospectively reviewed. Arthroscopy-assisted reduction of the fracture was performed, and a cannulated screw was placed using three-dimensional orthopedic robotic-assisted navigation. RESULTS: The patients (seven men, two women) had a mean age of 36.33 ± 9.77 years and were followed up for 21 ± 5.43 months. The operation time was 106.67 ± 24.5 min with blood loss of 47.78 ± 9.05 ml. Primary healing was obtained in all cases, and no patient sustained a nerve or tendon injury, had fracture nonunion, or developed talar osteonecrosis. One patient developed subtalar arthritis, for which subtalar joint fusion was performed; pain was markedly less severe after cleaning. CONCLUSION: Arthroscopy-assisted reduction and robotic-assisted screw placement have the advantages of visualization of fracture reduction, minimal injury, and precise screw placement in the treatment of fractures of the posterior talar process.

Radiographic Anatomy of the Lateral Ankle Ligament Complex: A Cadaveric Study.

BACKGROUND: When lateral ankle sprains progress into chronic lateral ankle instability (CLAI), restoring precise anatomic relationships of the lateral ankle ligament complex (LALC) surgically is complex. This study quantifies the radiographic relationships between the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and prominent osseous landmarks visible under fluoroscopy to assist in perioperative practices for minimally invasive surgery for CLAI. METHODS: Ten fresh frozen ankle specimens were dissected to expose the LALC and prepared by threading a radiopaque filament through the ligamentous footprints of the ATFL and CFL. Fluoroscopic images were digitally analyzed to define dimensional characteristics of the ATFL and CFL. Directional measurements of the ligamentous footprints relative to the lateral process of the talus and the apex of the posterior facet of the calcaneus were calculated. RESULTS: Dimensional measurements of the ATFL were a mean length of 9.3 mm, fibular footprint of 9.4 mm, and talar footprint of 9.1 mm. Dimensional measurements of the CFL were a mean length of 19.4 mm, fibular footprint of 8.2 mm, and calcaneal footprint of 7.3 mm. From the radiographic apparent tip of the lateral process of the talus, the fibular attachment of the ATFL was found 13.3 mm superior and 4.4 mm posterior, whereas the talar attachment was found 11.5 mm superior and 4.8 mm anterior. From the radiographic apparent posterior apex of the posterior facet of the calcaneus, the fibular attachment of the CFL was found 0.2 mm inferior and 6.8 mm anterior, whereas the calcaneal attachment was found 14.3 mm inferior and 5.9 mm posterior. CONCLUSION: The ATFL and CFL were radiographically analyzed using radiopaque filaments to outline the ligamentous footprints in their native locations. These ligaments were also localized with reference to 2 prominent osseous landmarks. These findings may assist in perioperative practices for keyhole incision placement and arthroscopic guidance. Perfect lateral ankle joint imaging with talar domes superimposed is required to be able to do this. CLINICAL RELEVANCE: Radiographic evaluation of the ATFL and CFL with reference to prominent osseous landmarks identified under fluoroscopy may assist in perioperative practices for minimally invasive surgery to address CLAI for keyhole incision placement and arthroscopic guidance.

The Use of the Lateral Tibial Line to Assess Ankle Alignment: A Preliminary Investigation.

BACKGROUND: Although the medial clear space (MCS) is commonly used to assess talar alignment and ankle stability, its measurement is variable with multiple reported normal values. We have observed that the lateral tibial shaft is a reliable landmark to assess talar alignment. The objective of the current investigation was to determine the normal relationship of the lateral tibia to the superolateral talus using a tangent drawn inferiorly from the lateral tibial shaft, which we refer to as the "lateral tibial line" (LTL). METHODS: The relationship of the LTL to the superolateral talus was assessed by three reviewers on 99 standing ankle mortise radiographs in uninjured patients. This relationship was quantified by measuring the distance (in millimeters) between the LTL and the superolateral talus. In addition, the interobserver reliability of the LTL measurement was recorded and compared with that of the MCS. RESULTS: The median value for the distance between the superolateral talus and LTL was -0.50 mm with an interquartile range of -1.4 to 0.0 mm. The LTL was within 1 mm of the lateral talus in 176 of 297 reviewer measurements (59.3%). Moreover, it was either lateral to or at most 1 mm medial to the lateral talus in 90.9% of cases. The LTL measurement also demonstrated good interobserver reliability (0.764, 95% confidence interval, 0.670 to 0.834), similar to the measurement of MCS (0.742, 95% confidence interval, 0.539 to 0.846). CONCLUSIONS: The relationship between the LTL and superolateral talus is easily measured with good reliability for assessing the anatomic relationship of the tibia and talus. The LTL uncommonly fell more than 1 mm medial to the superolateral talus, as might be seen with displaced ankle fractures. These findings will hopefully serve as a basis for future studies evaluating its role in assessing lateral displacement and stability of isolated fibula fractures. LEVEL OF EVIDENCE: Level III, retrospective review.

The developing juvenile talus: Radiographic identification of distinct ontogenetic phases and structural trajectories.

Trabecular bone architecture in the developing skeleton is a widely researched area of bone biomechanics; however, despite its significance in weight-bearing locomotion, the developing talus has received limited examination. This study investigates the talus with the purpose of identifying ontogenetic phases and developmental patterns that contribute to the growing understanding of the developing juvenile skeleton. Colour gradient mapping and radiographic absorptiometry were utilised to investigate 62 human tali from 38 individuals, ranging in age-at-death from 28 weeks intrauterine to 20 years of age. The perinatal talus exhibited a rudimentary pattern comparable to the structural organisation observed within the late adolescent talus. This early internal organisation is hypothesised to be related to the vascular pattern of the talus. After 2 years of age, the talus demonstrated refinement, where radiographic trajectories progressively developed into patterns consistent with adult trabecular organisation, which are linked to the forces associated with the bipedal gait, suggesting a strong influence of biomechanical forces on the development of the talus.

Comparison of different internal fixation implants in the treatment of talar neck fractures: A finite element analysis.

OBJECTIVES: This study aimed to analyze the biomechanics of cannulated screws (CS) with or without a lateral locking plate (LLP) in talar neck fractures through a finite element analysis. PATIENTS AND METHODS: The computed tomography image of the talus from a healthy volunteer (adult male) was used to reconstruct a three-dimensional talar model. The method for fixing talar neck fractures with CS and an LLP was planned using computer-aided design software. Afterward, the three-dimensional models of comminuted talar neck fractures were used to simulate fixation with anteroposterior parallel dual CS, single CS+LLP, and dual CS+LLP. Finally, finite element analysis was carried out to compare the outcomes of dual CS+LLP to those of single CS+LLP and to those of using dual CS alone. The displacement and von Mises stress values of the three groups with different internal fixation were analyzed. RESULTS: For a simple talar neck fracture, the lowest amount of displacement was obtained with CS+LLP (0.407 mm), while dual CS (0.459 mm) showed the highest amount of total displacement; the lowest amount of peak stresses was obtained with CS+LLP (5.38 MPa), while dual CS (8.749 MPa) showed the highest amount of total peak stresses. For a comminuted talar neck fracture, the lowest amount of displacement was obtained with CS+LLP (0.398 mm), while dual CS (0.408 mm) showed the highest amount of total displacement; the lowest amount of peak stresses was obtained with CS+LLP (129.9 MPa), while dual CS (205.9 MPa) showed the highest amount of peak stresses. CONCLUSION: Compared to the other two groups, the dual CS+LLP group had better biomechanics properties in the displacement and stress peak of the talus and implant. Thus, the use of dual CS+LLP fixation is recommended for the surgical treatment of comminuted talar neck fractures.

Is medial or lateral localization of osteochondral lesions of talus related to foot angles?

OBJECTIVES: This study aims to examine the relationship between foot angles and the presence and localization of osteochondral lesions of the talus (OLTs). PATIENTS AND METHODS: Between January 2014 and January 2019, a total of 152 patients with a diagnosis of medial OTLs (95 males, 57 females; mean age: 28.8±6.4 years; range, 18 to 40 years), 51 patients with a diagnosis of lateral OTLs (36 males, 15 females; mean age: 27.1±6.2 years; range, 18 to 39 years), and 114 patients without known foot-ankle trauma as the control group (56 males, 58 females; mean age: 29.0±6.1 years; range, 18 to 40 years) were included. Magnetic resonance imaging and radiographs of each group were analyzed retrospectively. Lateral talocalcaneal angle (LTCA), calcaneal inclination angle (CIA), Böhler angle (BA), and Gissane angle (GA) were measured on the images and the values were compared among the groups. RESULTS: The CIA had a significant relationship with the localization (p<0.001). It was higher in patients with OLTs and had an effect on localization. The mean CIA was 26.6º±3.9º in the medial OLTs group, 23.0º±3.5º in the lateral OLTs group, and 18.5º±3.6º in the control group. There was a significant difference in the LTCA between the control and OLTs groups (p<0.001). The LTCA was higher in patients with OLTs, but had no effect on localization. The mean LTCA was 41.1º±4.2º for medial OLTs, 41.3º±4.2º for lateral OLTs, and 35.7º±6.8º for the controls. No significant relationship was found for BA and GA among the three groups. CONCLUSION: Factors affecting the localization of OLTs are still not fully understood. However, foot morphology seems to play a role in determining medial or lateral localization. The LTCA is not related to the localization of OLTs; however, an increased LTCA may be related to the occurrence of OLTS. Increased CIA may be related to both OLTS localization and OLTs occurrence.

Morphological features of the non-affected side of the hindfoot in patients with unilateral varus ankle osteoarthritis.

BACKGROUND: The innate shape characteristics of the hindfoot bones alter the loading conditions of the foot and thus may be associated with an increased risk of developing varus ankle osteoarthritis (OA). This study aimed to clarify the innate morphological patterns of the hindfoot bones that may be associated with ankle OA by analyzing the differences between the bone morphology of the non-affected side of patients with unilateral varus ankle OA and that of healthy participants. METHODS: In this case-control study, computed tomography images were used to develop three-dimensional models of three hindfoot bones (distal tibia with fibula, talus, and calcaneus) from 23 non-affected sides of patients with radiography-diagnosed unilateral ankle OA and 22 healthy control participants. Anatomical and sliding landmarks were placed on the surface of each bone, and the principal components (PCs) of shape variation among specimens were independently calculated for each bone, preserving homology between individuals. The PC modes representing 5% or more of the overall variation were statistically compared between the ankle OA and control groups. RESULTS: Significant differences were identified between the OA and control groups in the fifth PC mode for the tibia with fibula (proportion of variance, 5.1%; p =.025), fifth PC mode for the talus (6.7%, p =.031), and third PC mode for the calcaneus (7.4%, p =.001). The hindfoot bones of the participants who developed ankle OA had the following innate morphological characteristics: the lateral malleolar articular surface of the fibula was shifted superiorly, tibial plafond was enlarged posteroinferiorly, posterior width of the talar trochlea was narrower, talonavicular articular surface of the talus was oriented more frontally, anterior-middle talocalcaneal articular surfaces of the talus were more medially shifted and those of the calcaneus were flatter, calcaneal sustentaculum tali was less protruding, and lateral plantar process of the calcaneus was more superiorly positioned. CONCLUSIONS: These distinctive morphological alterations may increase the incidence and progression of varus ankle OA through aberrant anterior translation, internal rotation, and varus tilting of the talus.

Primary Ewing's sarcoma of the talus.

Ewing's sarcoma is a malignant round cell tumour of bones and soft tissues that usually arises from the diaphyseal or meta-diaphyseal parts of long bones and less commonly from flat bones. It occurs rarely in the foot and if occurs, the calcaneus and the metatarsals are commonly involved. We present a case of a young woman diagnosed with primary Ewing's sarcoma of the talus with local spread to adjacent tarsals and the ankle joint. Ewing's sarcoma of feet, if present with even a trivial suspicion of spread either locally or distant, makes limb salvage surgery difficult. So, the treatment with radical surgery or by combined chemotherapy and radiotherapy should be considered-keeping in mind the complex anatomy of the foot and the difficulty in achieving tumour-free margins. Based on this experience, she underwent below-knee amputation. The patient received adjuvant chemotherapy and survived with a disease-free survival at the latest follow-up of 1 year.

Statistical shape modeling of mean shape and principal variability of the human talar bone in the Chinese population.

PURPOSE: The talar bone plays a crucial role in ankle biomechanics and stability. Understanding the shape variability of the talar bone within specific populations is essential for various clinical applications. In this study, we aimed to investigate the mean shape and principal variability of the human talar bone in the Chinese population using statistical shape modeling (SSM). METHODS: CT scans of 214 tali were included to create SSM models. Principal component analysis was used to describe shape variation among the male, female, and overall groups. RESULTS: The largest amount of variation among three groups ranges from 17.2%-18.8% of each variation. The first seven principal components (modes) captured 62.4%-67.5% of the cumulative variance. No dominant shape of the talus was found. Male tali generally have a larger size than the female tali, with the exception of the articular surface of the anterior subtalar joint. CONCLUSIONS: SSM is an effective method of finding mean shape and principal variability. Considerable variabilities were noticed among these three groups and all principal modes of variation. No dominant talar model was found to represent the majority of tali, regardless the gender. Such information is crucial to improve the current understanding of talar pathologies and their treatment strategies.

Anteromedial cannulated screw fixation for Hawkins II/III talus fractures in children: a retrospective study.

OBJECTIVE: To investigate the clinical effect of the anteromedial cannulated screw approach in the treatment of Hawkins II/III talus fractures in children. METHODS: A retrospective study was conducted on 20 children with talar fractures admitted to Renmin Hospital from September 2018 to February 2022. The fracture healing and functional recovery of the affected limb were strictly followed up after the operation. There were 14 males and 6 females. The average age was 9 years (range 6-12 years). According to the Hawkins classification, there were 12 cases of talar neck fracture type II and 8 cases of type III. All patients were fixed with cannulated compression screws via an anteromedial approach. According to the American Orthopedic Foot and Ankle Society ankle and hindfoot function scoring system, limb function was evaluated before and after the operation. A visual analog scale was used to evaluate the degree of postoperative pain. RESULTS: All 20 children were followed up for 12 months to 30 months, with an average of 15 months. We found that there was no significant difference in the excellent and good rate (76.9%) and necrosis rate (30.8%) between male children and female children (71.4%) and necrosis rate (28.6%) (P > 0.05). The excellent and good rates (92.9%) of children younger than 9 years old at the time of injury were higher than those of children older than 9 years old (33.3%), and the incidence of avascular necrosis of the talus was lower. The differences between the two groups were statistically significant (P < 0.05). The average prognosis score of children who underwent surgery within 5 days after injury was 89.2 ± 6.4, which was significantly higher than that of children who underwent surgery after 5 days (72.9 ± 13.1), and the difference was statistically significant (P < 0.05). There was no significant difference between patients who underwent surgery within 5 days after injury (15.4%) and those who underwent surgery after 5 days (51.7%) (P > 0.05). The excellent and good rates of talar neck fracture type II and talar neck fracture type III were 90.1% and 55.6%, respectively. CONCLUSION: The anteromedial approach combined with cannulated compression screws for the treatment of Hawkins II/III talus fractures in children not only has a clear surgical field, but the fracture can also be reduced and fixed under direct vision using this technique. It does not affect the stability of the ankle joint and is conducive to the recovery of ankle function. It can be used as a surgical scheme for the treatment of talar fractures in children.

Extruded talus injuries are associated with significant complications: A double center series with minimum 1-year follow up.

BACKGROUND: Extruded talus (ET) injuries are rare, but high-energy open pantalar dislocations. Literature on these injuries is sparse and optimal treatment protocols are ill defined. The current study documents the clinical and radiological outcomes in cases seen at 2 centers, in an attempt to determine whether surgeons should choose primary reimplantation or primary talectomy and fusion for these injuries. METHODS: Patients with ET injuries were identified from the database of two hospitals. Baseline demographics and treatment details were evaluated, and patients were called for follow-up. Radiological evaluation was conducted, and function was evaluated by the AOFAS hindfoot score. Outcomes and complications were compared between patients who had undergone primary talectomy versus primary reimplantation. Predictors of poor functional outcomes were determined. RESULTS: Of 23 patients seen by us, 15 were available for follow-up at 45.7 ± 22.2 months. Of these 19 had undergone reimplantation and 4 had talectomy with tibio-calcaneal arthrodesis. The mean percentage AOFAS score was 66.2 ± 14.6 at follow up. AVN was noted in 5, ankle arthrosis in 10, subtalar arthrosis in 4 and infection in 4 cases; no patient needed salvage arthrodesis during this time. There was no difference in baseline demographics, range of motion, AOFAS scores or complication rates between patients undergoing primary reimplantation versus primary talectomy. The number of complications per patient showed a negative, moderate correlation with the AOFAS score (Pearson's correlation coefficient 0.6, P value = 0.02). CONCLUSION: Despite best treatment, ET injuries result in significant impairment of functional outcomes and complications. Within the numbers available, no difference in outcomes or complication rates was noted between primary reimplantation or talectomy. However, we recommend reimplantation as the treatment of first choice as this offers the chance to salvage the ankle joint and preserves bone stock for future fusion or arthroplasty.

The Ankle Joint: Management of Significant Bone Loss with Arthrodesis.

Segmental bone loss of the distal tibia and/or talus presents a challenge to successful reconstruction for the foot and ankle surgeon. When conservative care has been exhausted, multiple surgical treatment options are available including bone transport, bulk allografts, bulk autografts, titanium cages, and external fixation techniques. The primary goals of surgical correction include restoration of limb length as well as a plantigrade, stable lower extremity.