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Yute Lin - One of the best experts on this subject based on the ideXlab platform.

  • chimeric free vascularized metatarsophalangeal Joint with Toe fillet flap a technique for reconstruction of the posttraumatic metacarpophalangeal Joint with concomitant soft tissue defect
    Journal of Hand Surgery (European Volume), 2018
    Co-Authors: Marco Pappalardo, Vincent G Laurence, Yute Lin
    Abstract:

    For painful, dysfunctional, posttraumatic metacarpophalangeal (MCP) Joints, the free vascularized Toe Joint transfer may represent a good solution. Successful reconstruction is potentially limited, however, by 2 features of the traditional vascularized metatarsophalangeal (MTP) transfer: inadequate arc of flexion and insufficient soft tissue coverage. The solution to both of these dilemmas lies in the manner of utilizing the donor site. Because of its innate hyperextensibility, rotating the MTP 180° volar to dorsal provides the greatest arc of flexion in the reconstructed MCP. Excellent soft tissue coverage can be provided by elevating the skin paddle of the transferred second Toe as a chimeric fillet flap, based on the tibial plantar digital artery.

  • the impact of transferred vascularized Toe Joint length on motion arc of reconstructed finger proximal interphalangeal Joints a cadaveric study
    Journal of Hand Surgery (European Volume), 2017
    Co-Authors: Chungchen Hsu, Charles Yuen Yung Loh, Steven L Moran, Dennis S Kao, Yute Lin
    Abstract:

    Vascularized Toe Joint transfer for finger proximal interphalangeal Joint reconstruction can result in sub-optimal arc of motion and extension lag due to inappropriate intercalated bony segment length. We investigated the impact of intercalated segment length on passive arc of motion and extension lag of the reconstructed proximal interphalangeal Joint. Cadaveric intercalated Joint grafts were harvested from lesser Toes and transferred to cadaveric fingers. The pre-determined finger proximal interphalangeal Joint defect size was 2 cm. Three different intercalated segment lengths were inserted and resulting proximal interphalangeal Joint arc of motion and extension lag were measured. The average arc of motion of finger proximal interphalangeal Joints was 81° and 54° for Toe proximal interphalangeal Joints. Long intercalated segments had an average arc of motion of 30° with 32° extension lag. Equal-length intercalated segments had an average 49° arc of motion with 15° extension lag. Short intercalated segments had an average arc of motion of 71° with 8° extension lag. Shorter intercalated segments provide the greatest reduction in extension lag.

  • the impact of transferred vascularized Toe Joint length on motion arc of reconstructed finger proximal interphalangeal Joint a cadaveric study
    Hand, 2016
    Co-Authors: Chungchen Hsu, Charles Yuen Yung Loh, Steven L Moran, Yute Lin
    Abstract:

    Objective: Vascularized Toe Joint transfer for finger proximal interphalangeal Joint (PIPJ) reconstruction is a well-described technique in the literature. However, the reconstructed PIPJ is known ...

  • improving the extensor lag and range of motion following free vascularized Joint transfer to the proximal interphalangeal Joint part 2 a clinical series
    Plastic and Reconstructive Surgery, 2013
    Co-Authors: Wee Leon Lam, Chungcheng Hsu, Yute Lin, Nicholas Waughlock, Fuchan Wei
    Abstract:

    BACKGROUND Free vascularized Joint transfer for reconstructing the posttraumatic proximal interphalangeal Joint has enjoyed limited popularity because of the low range of motion typically achieved after transfer. One of the commonest complaints is the significant extensor lag. Part 2 of this two-part study is focused on the clinical outcomes following a more anatomical approach to extensor tendon reconstruction. METHODS Nine patients (eight male and one female), with a mean age of 31.7 years, underwent free vascularized Joint transfer for posttraumatic proximal interphalangeal Joint injuries using the second Toe proximal interphalangeal Joint. In Part 1, two arrangements of the central slip mechanism were found: type I with an attenuated and type II with a distinct central slip. An algorithm was constructed using this information: in a type I Toe with sufficient recipient lateral bands, a centralization procedure was carried out; and when the lateral bands were insufficient, a modified Stack procedure was carried out. In type II Toe Joints, a tight repair of the corresponding extensor tendons was performed. RESULTS Four patients underwent centralization procedures, two underwent a modified Stack procedure, and three underwent tight extensor repair. At 23.4 months, the average extensor lag was 18.3 degrees. A total range of motion of 53.9 degrees (mean flexion, 72.2 degrees) was achieved that approximated 81.1 percent of the pretransfer passive range of motion at the Toe proximal interphalangeal Joint. CONCLUSION This preliminary result demonstrates that much improved range of motion can be achieved by reducing the extensor lag using an anatomical reconstruction that takes into account the recipient finger and Toe Joint anatomy. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, IV.

Charles Yuen Yung Loh - One of the best experts on this subject based on the ideXlab platform.

Chungcheng Hsu - One of the best experts on this subject based on the ideXlab platform.

  • rationalizing the vascular anatomy for oblique osteotomy of the metatarsal head during Toe Joint transfers of the metatarsophalangeal Joint
    Plastic and reconstructive surgery. Global open, 2018
    Co-Authors: Shihheng Che, Charles Yuen Yung Loh, Chungcheng Hsu
    Abstract:

    Background:The metatarsophalangeal Joint (MTPJ) of the lessor Toe has been used to reconstruct the metacarpophalangeal Joint. When an oblique osteotomy of the metatarsal head is performed, the orientation of the vascular pedicle is crucial to preserve the blood supply to the MTPJ. This study was con

  • Rationalizing the Vascular Anatomy for Oblique Osteotomy of the Metatarsal Head during Toe/Joint Transfers of the Metatarsophalangeal Joint
    Wolters Kluwer, 2018
    Co-Authors: Md ,yu-te Lin, Chungcheng Hsu, Shih-heng Chen, Charles Yuen Yung Loh, Mbbs Msc, Cheng-hung Lin
    Abstract:

    Background:. The metatarsophalangeal Joint (MTPJ) of the lessor Toe has been used to reconstruct the metacarpophalangeal Joint. When an oblique osteotomy of the metatarsal head is performed, the orientation of the vascular pedicle is crucial to preserve the blood supply to the MTPJ. This study was conducted to identify the path of the nutrient artery to the MTPJ. Methods:. We reviewed our operative records in consecutive series of 45 patients during Toe or Joint harvest. Retrograde dissection of the vascular pedicle was performed starting from the distal communicating artery at the first webspace toward the first dorsal metatarsal and first plantar metatarsal arteries. All the vessels related to the MTPJ were explored and ligated if the MTPJ was not included in the flap. Results:. The condylar branches to the proximal phalanx and the metaphyseal branches to the second metatarsus were barely identifiable during the dissections. The articular branch running perpendicularly from the plantar artery toward the plantar surface of MTPJ was verified in all cases. The articular branches originated either from the first plantar metatarsal artery (92.1%) or from the tibial plantar digital artery (7.9%). The external diameter of the articular branches was around 0.5–1 mm. When the articular branch was included and preserved, the metatarsal heads oozed immediately after the flap was reperfused. Conclusions:. The study demonstrated the constant and sizable articular branch of the MTPJ that originates from the plantar artery system. The consistency of the vascular anatomy enables oblique osteotomies of the metatarsal head to be performed without fear of injury to the pedicle

  • improving the extensor lag and range of motion following free vascularized Joint transfer to the proximal interphalangeal Joint part 2 a clinical series
    Plastic and Reconstructive Surgery, 2013
    Co-Authors: Wee Leon Lam, Chungcheng Hsu, Yute Lin, Nicholas Waughlock, Fuchan Wei
    Abstract:

    BACKGROUND Free vascularized Joint transfer for reconstructing the posttraumatic proximal interphalangeal Joint has enjoyed limited popularity because of the low range of motion typically achieved after transfer. One of the commonest complaints is the significant extensor lag. Part 2 of this two-part study is focused on the clinical outcomes following a more anatomical approach to extensor tendon reconstruction. METHODS Nine patients (eight male and one female), with a mean age of 31.7 years, underwent free vascularized Joint transfer for posttraumatic proximal interphalangeal Joint injuries using the second Toe proximal interphalangeal Joint. In Part 1, two arrangements of the central slip mechanism were found: type I with an attenuated and type II with a distinct central slip. An algorithm was constructed using this information: in a type I Toe with sufficient recipient lateral bands, a centralization procedure was carried out; and when the lateral bands were insufficient, a modified Stack procedure was carried out. In type II Toe Joints, a tight repair of the corresponding extensor tendons was performed. RESULTS Four patients underwent centralization procedures, two underwent a modified Stack procedure, and three underwent tight extensor repair. At 23.4 months, the average extensor lag was 18.3 degrees. A total range of motion of 53.9 degrees (mean flexion, 72.2 degrees) was achieved that approximated 81.1 percent of the pretransfer passive range of motion at the Toe proximal interphalangeal Joint. CONCLUSION This preliminary result demonstrates that much improved range of motion can be achieved by reducing the extensor lag using an anatomical reconstruction that takes into account the recipient finger and Toe Joint anatomy. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, IV.

Karl E Zelik - One of the best experts on this subject based on the ideXlab platform.

  • adding a Toe Joint to a prosthesis walking biomechanics energetics and preference of individuals with unilateral below knee limb loss
    Scientific Reports, 2021
    Co-Authors: Kirsty A Mcdonald, Gerasimos Bastas, Rachel H Teater, Justin P Cruz, John T Kerr, Karl E Zelik
    Abstract:

    Toe Joints play an important functional role in able-bodied walking; however, for prosthesis users, the effect of adding a Toe Joint to a passive prosthetic foot remains largely unknown. The current study explores the kinematics, kinetics, rate of oxygen consumption and user preference of nine individuals with below-knee limb loss. Participants walked on a passive prosthetic foot in two configurations: with a Flexible, articulating Toe Joint and with a Locked-out Toe Joint. During level treadmill gait, participants exhibited a decrease in Push-Off work when using the Flexible Toe Joint prosthesis versus the Locked Toe Joint prosthesis: 16% less from the prosthesis (p = 0.004) and 10% less at the center of mass level (p = 0.039). However, between configurations, participants exhibited little change in other gait kinematics or kinetics, and no apparent or consistent difference in the rate of oxygen consumption (p = 0.097). None of the traditional biomechanical or metabolic outcomes seemed to explain user preference. However, an unexpected and intriguing observation was that all participants who wore the prosthesis on their dominant limb preferred the Flexible Toe Joint, and every other participant preferred the Locked configuration. Although perhaps coincidental, such findings may suggest a potential link between user preference and limb dominance, offering an interesting avenue for future research.

  • effects of Toe length foot arch length and Toe Joint axis on walking biomechanics
    Human Movement Science, 2020
    Co-Authors: Eric C Honert, Gerasimos Bastas, Karl E Zelik
    Abstract:

    Abstract Toe Joint articulation has been shown to affect gait mechanics, as evidenced by walking simulations, biped robots, and foot prostheses. However, it is not known how parameters such as Toe length, foot arch length (i.e., heel-to-Toe-Joint length) or Toe Joint axis angle affect human walking. We utilized a previously developed adjustable ankle-Toe prosthesis to systematically examine these three foot parameters. We tested ten able-bodied persons walking on a force instrumented-treadmill while wearing a pair of adjustable prostheses attached bilaterally below simulator boots (which fixated their biological ankles). We collected motion and ground reaction force data to compute lower-limb kinematics and kinetics as well as COM power and work. We observed that increasing the foot arch length by 60 mm (35%) increased COM Push-off work by ~5 J, due to increased energy storage and return by the ankle spring. Increasing the Toe length by 40 mm (80%) and changing the Toe Joint axis by ±9° from a neutral angle resulted in negligible effects on COM mechanics and lower limb kinetics. This study provides further insights regarding Toe Joint function; knowledge which may benefit the design/integration of Toe Joints into prostheses, exoskeletons and legged robots.

  • effect of Toe Joint stiffness and Toe shape on walking biomechanics
    Bioinspiration & Biomimetics, 2018
    Co-Authors: Eric C Honert, Gerasimos Bastas, Karl E Zelik
    Abstract:

    During typical human walking, the metatarsophalangeal Joints undergo extension/flexion, which we term Toe Joint articulation. This Toe Joint articulation impacts locomotor performance, as evidenced by prior studies on prostheses, footwear, sports and humanoid robots. However, a knowledge gap exists in our understanding of how individual Toe properties (e.g. shape, Joint stiffness) affect bipedal locomotion. To address this gap, we designed and built a pair of adjustable foot prostheses that enabled us to independently vary different Toe properties, across a broad range of physiological and non-physiological values. We then characterized the effects of varying Toe Joint stiffness across a range of different ankle Joint stiffness conditions, and the effects of varying Toe shape on walking biomechanics. Ten able-bodied individuals walked on a treadmill with prostheses mounted bilaterally underneath simulator boots (which immobilized their biological ankles). We collected motion capture and ground reaction force data, then computed Joint kinematics and kinetics, and center-of-mass (COM) power and work. To our surprise, we found that varying Toe Joint stiffness affected COM Push-off dynamics during walking as much as, or in some cases even more than, varying ankle Joint stiffness. Increasing Toe Joint stiffness increased COM Push-off work by up to 48% (6 J), and prosthetic anklefoot Push-off work by up to 181% (12 J). In contrast, large changes in Toe shape had little effect on gait. This study brings attention to the Toes, an aspect of prosthetic and robotic foot design that is often overlooked or overshadowed by design of the ankle. Optimizing Toe Joint stiffness in assistive and robotic devices (e.g. prostheses, exoskeletons, robot feet) may provide a complementary means of enhancing Push-off or other aspects of locomotor performance, in conjunction with the more conventional approach of augmenting ankle dynamics. Future studies are needed to isolate the effects of additional Toe properties (e.g. Toe length).

Lei Ren - One of the best experts on this subject based on the ideXlab platform.

  • phalangeal Joints kinematics during ostrich struthio camelus locomotion
    PeerJ, 2017
    Co-Authors: Rui Zhang, Gang Luo, Shuliang Xue, Lei Ren
    Abstract:

    The ostrich is a highly cursorial bipedal land animal with a permanently elevated metatarsophalangeal Joint supported by only two Toes. Although locomotor kinematics in walking and running ostriches have been examined, these studies have been largely limited to above the metatarsophalangeal Joint. In this study, kinematic data of all major Toe Joints were collected from gaits with double support (slow walking) to running during stance period in a semi-natural setup with two selected cooperative ostriches. Statistical analyses were conducted to investigate the effect of locomotor gait on Toe Joint kinematics. The MTP3 and MTP4 Joints exhibit the largest range of motion whereas the first phalangeal Joint of the 4th Toe shows the largest motion variability. The interphalangeal Joints of the 3rd and 4th Toes present very similar motion patterns over stance phases of slow walking and running. However, the motion patterns of the MTP3 and MTP4 Joints and the vertical displacement of the metatarsophalangeal Joint are significantly different during running and slow walking. Because of the biomechanical requirements, osctriches are likely to select the inverted pendulum gait at low speeds and the bouncing gait at high speeds to improve movement performance and energy economy. Interestingly, the motions of the MTP3 and MTP4 Joints are highly synchronized from slow to fast locomotion. This strongly suggests that the 3rd and 4th Toes really work as an "integrated system" with the 3rd Toe as the main load bearing element whilst the 4th Toe as the complementary load sharing element with a primary role to ensure the lateral stability of the permanently elevated metatarsophalangeal Joint.