bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arthroscopic Plafond Access for Osteochondral Lesions- The Effect of Limited Ankle Range of Motion on Anterior and Posterior Arthroscopic Accessibility
Authors: Akoh Craig C. , Phisitkul Phinit , Rungprai Chamnanni , Amendola Annunziato , Hartog Bryan Den , Glass Natalie A. 
Published: October 2016

Category: Arthroscopy. Introduction/Purpose: Osteochondral lesions of the tibial plafond (OLTPs) can lead to chronic ankle pain and disability. Arthroscopic treatment has been described after failure of initial nonoperative treatment. However, the ideal appropriate approach for OLTPs is controversial, and it is not known if ankle positioning or joint distraction affects the accessibility of these lesions. The purpose of this study was to determine the effects of predetermined ankle flexion angles on arthroscopic accessibility of the distal tibial articular surface through either the anterior or posterior approach. The effects of non- invasive joint distraction were also analyzed. Methods: Fourteen below-knee cadaver specimens were subjected to pre-operative range of motion measurements. Joint distraction was measured using sizing rods with the precision of 1 mm. The accessible areas at the tibial plafond were marked using a curette at predetermined ankle positions. Arthroscopy was performed using a 30-degree 2.7 mm camera via standard anterior and posterior approaches in randomized fashion in all specimens. Following arthroscopic accessibility, each cadaveric ankle was disarticulated and arthroscopic accessibility was quantified using a surface laser scan. Statistical analyses were performed to determine the correlation between pre-operative ankle range of motion and amount of distraction on arthroscopic accessibility of the tibial plafond. Results: The average accessibility of the tibial plafond was 56 percent and 68 percent for the anterior and posterior approaches, respectively (p = 0.056). There was no difference in accessibility from the anterior approach with increasing level of plantarflexion (p >0.05). Increasing dorsiflexion during the posterior approach significantly reduced ankle accessibility (p = 0.028). There was a significant increase in accessibility through either anterior or posterior approach with increasing level of ankle distraction; (parameter estimates ±SE): anterior= 14.2±3.34, p < 0.01 and posterior= 10.6±3.7, p < 0.05). Conclusion: Arthroscopic accessibility for the treatment of OLTPs was vastly dependent on the amount of intra-operative joint distraction achieved. Posterior approach had more joint distraction and wider plafond accessibility. Increasing ankle distraction significantly improved arthroscopic plafond accessibility for both anterior and posterior approaches while ankle joint position did not influence accessibility from either approach.
Trabecular Metal Total Ankle Using Transfibular Approach
Authors: Barg Alexej , Lyman Mikayla , Gililland Jeremy 
Published: October 2016

Category: Ankle Arthritis Introduction/Purpose: The Trabecular Metal total ankle, introduced in 2012, is the most recent design of a lateral approach, total ankle replacement. The objectives of this study were to (1) determine postoperative radiographic outcomes including hindfoot alignment, alignment of prosthesis components, and periprosthetic radiolucencies, and (2) determine the failure rate of prosthesis components in the short-term. Methods: Fifty-six consecutive primary total ankle replacements were performed between October 2012 and November 2014 using a Trabecular Metal prosthesis (Zimmer Biomet, Warsaw, IN, USA) through transfibular approach. There were 30 male and 26 female patients with a mean age of 66.7 ± 9.2 years (46.7–84.9). Radiographic assessment was performed using preoperative and postoperative weight-bearing radiographs (Figure 1). Periprosthetic radiolucency was assessed by two independent observers, according to each of the 6 zones around the tibial and talar components. Hindfoot alignment was analyzed by medial distal tibial angle, tibio-talar tilt, calcaneal moment arm, and anterior distal tibial angle. Degenerative changes in the tibiotalar and adjacent joints were assessed according to the Kellgren-Lawrence scale. Prosthesis alignment was measured by α, β, and γ angles. The mean time to final follow-up was 19.5 ± 5.2 months (12.0-32.8). All patients were available for a minimum of one year of follow-up. Results: At the latest follow-up, radiolucencies were observed in tibial zones 1 through 6 in 33.9%, 26.8%, 7.1%, 5.4%, 10.7%, and 21.4%, respectively. Radiolucencies were seen in talar zones 1 through 6 in 12.5%, 3.6%, 0.0%, 0.0%, 5.4%, and 0.0%, respectively. The prosthesis alignment α, β, and γ angles were 87.0° ± 3.1° (80°–95°), 87.1° ± 5.3° (75°–100°), and 5.2° ± 6.1° (-7°–20°). In all patients, osseous union of the fibular osteotomy was observed within 4 months postoperatively. In two patients, a painful loosening of the tibial component was observed, resulting in revision of tibial component at 17.6 and 24.6 months after the index procedure. Conclusion: The short-term results of a lateral approach, Trabecular Metal implant are encouraging and comparable with those of other third-generation ankle implants. All osteotomies healed in appropriate alignment.
A New Concept of 3D Biometric for Hindfoot Alignment Using Weight Bearing CT
Authors: Lintz François , Welck Matthew J. , Goldberg Andy J. 
Published: October 2016

Category: Hindfoot Introduction/Purpose: Hindfoot alignment measures based on 2D radiographs present many anatomical and operator-related bias and do not account for the contribution of the forefoot in ankle biomechanics. Weight-bearing CT provides an opportunity to solve this. In this study, a new system: TALAS™ (Torque Ankle Lever Arm System) designed for weight-bearing CT was used to calculate an innovative 3D biometric: FAO (Foot Ankle Offset) which represents the lever arm generated in the ankle from the actions of body weight and ground reaction force. The objective was to describe the distribution of FAO in a series of anonymised datasets from clinically normal or varus cases. We hypothesized that normal and varus cases should be significantly different and that the distribution should be Gaussian in the normal population. Methods: This is a retrospective cohort study, level 3 evidence. Thirty four anonymous datasets (26 normal, 8 varus) from weight bearing scans (PedCAT, CurveBeam LLC, Philadelphia, USA) were obtained from an existing database in a specialized foot and ankle unit. Datasets were screened by an independent observer who collected the 3D coordinates of specific anatomical landmarks, which included the weight bearing points of the calcaneus, and the 1st and 5th metatarsal heads as well as the highest and centermost point on the talar dome. This data was processed with the TALAS™ system, which resulted in an FAO value for each case, given as a percentage of foot length. Results: Mean value for the Foot Ankle Offset in normal cases was 2.34%, Median was 2.44% (range:-3.22; 9.09%), Standard Deviation was 2.92%. In varus cases, Mean was -11.36%, Median was -10.74%(range:-22.36;-1.05), Standard Deviation was 9.19%. FAO values were significantly different in normal and varus cases (p < 0,005). The distribution of the normal population demonstrated a Gaussian shape. Conclusion: This pilot study suggests that the FAO is efficient in measuring hindfoot alignment using weight bearing CT. Drawbacks are the limited number of cases and the use of a beta version of TALAS™ which requires more development in order to be usable in daily practice. Further research in larger patient populations is necessary. Previously published research in this field had looked at weight bearing CT but only tried to adapt 2D biometrics. The present study suggests the possibility of discovering and describing new 3D biometrics in the foot and ankle field.
Adjacent Joint Kinematics after Ankle Arthrodesis in Cadaveric Gait Simulation
Authors: Demetracopoulos Constantine A. , Sturnick Daniel R. , Ellis Scott J. , Deland Jonathan T. , Baxter Josh R. 
Published: October 2016

Category: Ankle Arthritis Introduction/Purpose: Ankle arthrodesis is an effective treatment for decreasing pain in patients with end-stage ankle arthritis. However, all patients with an ankle arthrodesis will eventually develop adjacent joint arthritis. The etiology of adjacent joint arthritis after ankle arthrodesis is not fully understood due to the difficulty of investigating these joints in vivo. Cadaveric simulation provides a unique capability of studying intrinsic foot and ankle joint mechanics. The objective of this study was to establish the effect of ankle arthrodesis on adjacent joint kinematics using cadaveric gait simulation. We hypothesized that adjacent joint motion of the hindfoot would increase after ankle arthrodesis. Methods: Four mid-tibia cadaveric specimens were potted and secured to a static mounting fixture about a six-degree of freedom robotic platform.(Figure 1A) The nine extrinsic ankle tendons were isolated and connected to linear actuators instrumented with load cells in series. During simulations, a force plate was moved relative to the stationary specimen through an inverse tibial kinematic path. Three-dimensional ankle and hindfoot kinematics were captured using a motion capture system. After ankle arthrodesis, kinematics were recorded using the same muscle force and kinematic inputs as the intact condition to determine how the hindfoot would behave when simulating normal gait. To assess the effect of ankle arthrodesis during simulated walking on adjacent joint kinematics, pre- and post-arthrodesis kinematics of the subtalar and talonavicular joint were directly compared along the stance phase and differences were assessed using two-tailed, paired Student’s t-tests with an alpha value set at p = 0.05. Results: Subtalar and talonavicular joint plantarflexion was greater during the early phase of stance in the ankle arthrodesis condition.(Figure 1B and 1C). Talonavicular joint motion also demonstrated greater dorsiflexion during late stance following ankle arthrodesis (Figure 1C). Ankle arthrodesis had no detectable effect on axial or coronal plane motion in adjacent joints of the hindfoot. Conclusion: This study reveals that sagittal plane motion in the hindfoot is increased following ankle arthrodesis. These results provide further insight into how motion is redistributed to adjacent joints after arthrodesis during gait. Such compensatory motions may be related to changes in contact mechanics in adjacent joints which can lead to degenerative changes.
A Biomechanical Comparison of First Metatarsophalangeal Arthrodesis Using Crossed Screws and Shape-Memory Staples in Various Configurations
Authors: Grice John E. , Willmott Henry , Halewood Camilla , MBiomedE MEng , Dunning Mike , Amis Andrew 
Published: October 2016

Category: Midfoot/Forefoot Introduction/Purpose: Arthrodesis of the first metatarsophalangeal joint (MTPJ) is a commonly performed procedure for the treatment of hallux rigidus. A range of fixation methods have been used. Most recently, the shape-memory staple has been described. Made from an equiatomic alloy, the staple changes its shape when heated to body temperature so as to provide compression across the arthrodesis. We aimed to determine load to failure, cyclic loading and failure characteristics of different staple configurations compared to crossed screws. Methods: A cadaveric porcine model was used to simulate first MTPJ arthrodesis. Five forms of fixation were tested: single vertical staple; single horizontal staple; paired staples in orthogonal superior-inferior and medial-lateral configuration (0-90° to sagittal plane); paired staples in an oblique orthogonal configuration (45-135° to sagittal plane); two crossed screws. Using a materials-testing machine, specimens were loaded in dorsiflexion to simulate weight bearing. Cyclical loading was performed from 5-40N at a rate of 0.5 Hz for 1000 cycles. Plantar gapping, shear and creep were measured. Specimens were then loaded to failure in order to generate a load-displacement curve. The mechanism of failure was noted for each group. Results: Single staple configurations failed at very low loads. Single vertical staples failed at a mean load 15N±5N and single horizontal staples at 19N±3N. Mean failure load for paired 0-90° staples was 43N±9N which was significantly lower than the paired 45-135° staples which failed at 141N±25N (p < 0.001) and crossed screws, which failed at 180N±67N (p < 0.001). The was no significant difference between the 45-135° staples and crossed screws. Cyclic testing demonstrated plantar gap formation of 0.2mm±0.1 mm in the crossed screw specimens and 0.4mm±0.4 mm in the 45-135° staple specimens. However, stapled specimens demonstrated more shear compared to crossed screws (mean 1.0mm±0.5 mm compared to 0.14mm±0.4 mm, p < 0.01). Furthermore, crossed screw specimens showed mainly plastic deformation whereas stapled specimens showed combined plastic and elastic deformation. Conclusion: First MTPJ arthrodeses fixed with single staples failed at very low loads and cannot be recommended. The widely accepted 0-90° orthogonal staple configuration proved to be significantly less strong than two crossed screws. However, changing staple position to an oblique configuration at 45° and 135° to the sagittal plane significantly improved stability, rendering the construct as strong as crossed screws. Nevertheless, none of the constructs would have been strong enough to withstand full weight-bearing in the immediate post-operative period.
Does Arthrodesis of the First Metatarso-Phalangeal Joint Correct the Intermetatarsal M1M2 Angle? Analysis of Continuous Series of 208 Arthrodesis Plate-Osteosyntheses
Authors: Besse Jean-Luc , Dalat Frederic , Cottalorda Francois , Fessy Michel-Henry 
Published: October 2016

Category: Midfoot/Forefoot Introduction/Purpose: MTP-1 arthrodesis allows effective correction of both inter-metatarsal M1M2 and M1P1 angles. Undercorrection of wide M1M2 angle after MTP-1 arthrodesis causes persistently wide forefoot, metatarsalgia and unaesthetic gap between first and second toes. In severe deformities, Rippstein recommended supplementary first metatarsal osteotomy or cuneo-metatarsal arthrodesis. The present study sought to investigate correction of inter-metatarsal M1M2 angle after MTP-1 arthrodesis according to aetiology and pre-operative deformity severity. Methods: A prospective continuous series (June 2007- March 2011) included 208 patients: 48% severe hallux valgus and/or osteoarthritis, 18% hallux rigidus, 16% rheumatoid osteoarthritis, 13% revision, 5% hallux varus; mean age, 62.4±9.9 years (19-87 years). All patients were operated on by a single senior surgeon with the same technique: articular surface reaming (cup-ball), osteosynthesis with titanium anatomical plate (Fyxis-Biotech) and the same rehabilitation procedure. Pre- and post-operative hallux positions were analysed on antero-posterior and lateral weightbearing views. M1M2 and M1P1 were measured according to American Orthopaedic Foot and Ankle Society guidelines. Results: Mean follow-up was 18.6±12.4 months; fusion rate, 97%; 5% plate removal. Mean M1P1 angle was 33.8±19.7° (-45° to 67°) preoperatively, and 13.4±5.3° (0-32°) at follow-up; M1M2, 14.2±5.4° (0° to 26°) and 6.5± 2.3° (0-12°) respectively. M1M2 angle was < 15° in 97 patients, 15-19° in 78 and ≥20° in 33 preoperatively, and respectively 5.8±2.1° (0-10°), 6.7±2.2° (0-10°) and 8.1±2.4° (3-12°) at follow-up. No significant differences were observed according to aetiology. M1M2 angle was >10° in only 2 patients (0.9%) associated with cuneometatarsal osteoarthritis. Improvement increased with severity of preoperative M1M2 angle (p < 0.05). However, mean postoperative M1M2 angle in the severe group was nevertheless wider than in the moderate group. Conclusion: MTP1-arthrodesis corrected M1M2 angle even in severe deformity, of whatever aetiology, in agreement with the literature, whereas Rippstein recently recommended supplementary M1 osteotomy or C1M1 arthrodesis for preoperative M1M2 angle >10°. Pydah correlated preoperative and postoperative intermetatarsal angle with a regression line, without recommending any secondary procedure to improve M1M2 angle. In severe increased preoperative M1M2 angle, we do not recommend associating systematic C1M1 arthrodesis or basal metatarsal osteotomy to MTP-1 arthrodesis, but suggest that additional basal metatarsal osteotomy or C1M1 fusion might be required only in exceptional associated degenerative C1M1 joint.
Effect of First Ray Insufficiency and Metatarsal Index on Metatarsalgia in Hallux Valgus
Authors: Slullitel Gaston , Lopez Valeria , Calvi Juan P. , Seletti Maximiliano C. , Bartolucci Carla , Pinton Gustavo 
Published: October 2016

Category: Midfoot/Forefoot Introduction/Purpose: There are two concepts that tried to explain the etiology of metatarsalgia in hallux valgus patients: First, the one that states that as the magnitude of hallux valgus increases, there is a mechanical overload of the lesser metatarsals. Second, that an increased relative lesser metatarsal length is a factor in the development of metatarsalgia. However there is no current evidence that these facts predisposes for primary metatarsalgia. The purpose of the study was to evaluate the factors associated with metatarsalgia in hallux valgus patients. Methods: A cross-sectional study of 121 consecutive adult patients with non-arthritic hallux valgus was carried out. Binary logistic regression was performed to identify the effect of the clinical and demographic factors on the occurrence of metatarsalgia. Results: One hundred twenty one patients (184 feet) with hallux valgus were analyzed. The median weight was 65 Kg (IQR 58 – 72). Metatarsalgia was present in 84 (45.6%) feet. The binary logistic regression showed that lesser toe deformity (OR 2.6 IC95% 0.2-0.5), gastrocnemius shortening (OR 5.8 IC95% 2.8-12.3), metatarsal index (OR 0.3 IC95% 0.2-0.5) and weight (OR 2.5 IC95% 1.2-5.3) were significantly associated. Conclusion: Metatarsalgia occurs in almost a half of hallux valgus patients. It has a multifactorial etiology. Our finding questions the common theory that both the magnitude of hallux valgus deformity and an increased length of a lesser metatarsal by themselves, predisposes for primary metatarsalgia. Metatarsalgia was associated with Achilles shortening, excessive weight and associated lesser toe deformity. These factors should be addressed in order to treat this disorder adequately.
The Use of Infrared Thermometry in Confirming First Metatarsophalangeal Joint Fusion
Authors: Mayich D. Joshua , Myerson Mark S. , MacNeill A. Luke 
Published: October 2016

Category: Midfoot/Forefoot Introduction/Purpose: Confirming the presence or absence of union is a critical determination in the care of individuals following attempted surgical fusion. This most commonly is done using clinical examination in conjunction with imaging. Infrared thermometry (IRT) has been used in other areas of clinical foot and ankle care, and has been shown to be a reliable method of measuring skin temperature. Given the complex morphology of the foot and ankle and the confounding clinical presentation of cases of foot and ankle fusions during the post-operative recovery, trying to determine the presence of absence of clinical union can be difficult. An adjunctive method to further inform the post-operative recovery would be helpful. In this study, IRT is investigated as an adjunctive method of confirming clinical union of attempted first metatarsophalangeal (or 1st MTP) fusion. Methods: Thirty-three individuals undergoing 1st MTP joint fusion were prospectively measured using IRT. Temperature at the 1st MTP site was recorded preoperatively, 10-14 days postoperatively, 42 days postoperatively, and 90 days postoperatively. Each case was followed post-operatively as per usual clinical care guidelines, and union was confirmed by a combination of clinical examination and radiographs. All data were collected from two testing centers, using compatible IRT devices. Results: Temperature at the 1st MTP site increased from preoperatively (82.7°F ± 4.4°) to 10-14 days postoperatively (89.2°F ± 2.7°; p < .001); it declined from 10-14 days postoperatively to 42 days postoperatively (84.5°F ± 3.9°; p < .001); and it declined from 42 days postoperatively to 90 days postoperatively (81.5°F ± 4.6°; p < .001). The final temperature was statistically not significant from the pre-operative value, or the value measured on the opposite 1st MTP joint. Temperature data collected from one of the testing centers was significantly higher than the data collected from the other center (p < .001), suggesting a potential location or climate effect. No non-unions were recorded during the study. Conclusion: Results suggest that IRT was successful in predicting and confirming union in the setting of 1st MTP joint fusion - where temperature of the 1st MTP joint returned to pre-operative and opposite side levels. For this reason, IRT presents itself as a valuable adjunct in the setting of 1st MTP joint fusion. Collecting contralateral foot temperature data may be a less biased means of tracking the progression of healing than the use of absolute foot temperatures, and a method to avoid regional ambient temperature differences.