Current Organizations / Institutes

The organizations/institutes from the scholar's latest article

Previous Organizations / Institutes

The organizations / institutes from the scholar's other articles in the past ten years


Toran D. MacLeod has a total of 72 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Prosthesis Embodiment in Lower Extremity Limb Loss: A Narrative Review

    by Tuyet Thao Nguyen, Bingjie Wang, Haddy Alas, Quincy Jones, Chase Clark, Sabrina Lazar, Shaddy Malik, Joshua Graham, Yasmeen Talaat, Chris Shin, et al.

    Lower limb prosthesis abandonment is a significant challenge, leading to reliance on walking aids, such as wheelchairs, which frequently do not match the patient’s needs and lead to increased morbidity. Prosthesis abandonment is driven by a lack of embodiment, the latter defined as the integration of a prosthetic device into one’s body schema. This review evaluates interventions enhancing embodiment through three dimensions: ownership, agency, and co-location. The aim of this narrative review is to ask what interventions are available to improve embodiment, and what dimensions of embodiment should be included in the standard of care for lower-limb amputation surgery and componentry development. This narrative is constructed through a thorough literature search on how the aforementioned dimensions of embodiment can be optimized. In the studies reviewed, standardization of embodiment metrics and longitudinal data are lacking, hindering clinical translation. Future work must prioritize patient-centered design, integrate multidimensional assessments, and address practical issues to expand eligibility for advanced interventions.


  • Open Access

    Kinematic and Radiographic Evaluation of Acromioclavicular Reconstruction with a Synthetic Ligament

    by Rafael F. Escamilla, Chad Poage, Scott Brotherton, Toran D. MacLeod, Charles Leddon, James R. Andrews

    Purpose. The optimal surgical technique for unstable acromioclavicular (AC) and coracoclavicular (CC) joint injuries has not yet been established. The biomechanical and radiographic effect of the LockDown device, a synthetic ligament for AC joint reconstruction, was evaluated to assess the optimal surgical technique for unstable AC and CC joint injuries. It was hypothesized that the LockDown device would restore AC joint kinematics and radiographic stability to near native values. Methods. Three fresh frozen cadaveric torsos (6 shoulders) modelled CC joint motion in their “native,” “severed,” and “reconstructed” states. The effects of stressed and unstressed native, severed, and reconstructed conditions on AC separation and CC distances in anteroposterior, mediolateral, and inferosuperior directions during shoulder abduction, flexion, and scaption were assessed. The analysis of variance (, 0.05) was used to compare CC distance and peak AC distance in anteroposterior, mediolateral, and inferosuperior directions during shoulder flexion, abduction, and scaption measurements among native, severed, and reconstructed states with unstressed and stressed Zanca radiographic views. Results. From radiographic analyses, the CC distance was significantly greater ( ) across the surgical state in stressed versus unstressed views. Mean difference between stressed and unstressed views was 1.8 mm in native state, 4.1 mm in severed state, and 0.9 mm in reconstructed state. The CC distance was significantly greater in the “severed” state (10.4 mm unstressed; 14.5 mm stressed) compared to the “native” state ( ) (6.5 mm unstressed; 8.3 mm stressed) and compared to the “reconstructed” state ( ) (3.1 mm unstressed; 4.0 mm stressed) and significantly less ( ) in the “reconstructed” state compared to the “native” state. CC distances decreased from native to reconstructed, an average of 3.3 mm for unstressed and 4.3 mm for stressed. On average, peak AC joint separation distance in anteroposterior, mediolateral, and inferosuperior directions during shoulder-abduction, flexion, and scaption was shown to be restored to 11.5 mm of native values after reconstruction with LockDown device. Conclusion. Reconstruction of AC joint with LockDown synthetic ligament restores motion of clavicle and acromion to near native values, thereby decreasing scapular dyskinesis and enhancing AC joint stability.


  • Top Cited Papers

    Effects of and Response to Mechanical Loading on the Knee

    by David S. Logerstedt, Jay R. Ebert, Toran D. MacLeod, Bryan C. Heiderscheit, Tim J. Gabbett, Brian J. Eckenrode

    Mechanical loading to the knee joint results in a differential response based on the local capacity of the tissues (ligament, tendon, meniscus, cartilage, and bone) and how those tissues subsequently adapt to that load at the molecular and cellular level. Participation in cutting, pivoting, and jumping sports predisposes the knee to the risk of injury. In this narrative review, we describe different mechanisms of loading that can result in excessive loads to the knee, leading to ligamentous, musculotendinous, meniscal, and chondral injuries or maladaptations. Following injury (or surgery) to structures around the knee, the primary goal of rehabilitation is to maximize the patient’s response to exercise at the current level of function, while minimizing the risk of re-injury to the healing tissue. Clinicians should have a clear understanding of the specific injured tissue(s), and rehabilitation should be driven by knowledge of tissue-healing constraints, knee complex and lower extremity biomechanics, neuromuscular physiology, task-specific activities involving weight-bearing and non-weight-bearing conditions, and training principles. We provide a practical application for prescribing loading progressions of exercises, functional activities, and mobility tasks based on their mechanical load profile to knee-specific structures during the rehabilitation process. Various loading interventions can be used by clinicians to produce physical stress to address body function, physical impairments, activity limitations, and participation restrictions. By modifying the mechanical load elements, clinicians can alter the tissue adaptations, facilitate motor learning, and resolve corresponding physical impairments. Providing different loads that create variable tensile, compressive, and shear deformation on the tissue through mechanotransduction and specificity can promote the appropriate stress adaptations to increase tissue capacity and injury tolerance. Tools for monitoring rehabilitation training loads to the knee are proposed to assess the reactivity of the knee joint to mechanical loading to monitor excessive mechanical loads and facilitate optimal rehabilitation.


    • 1 January 2021
      • Vol. 50  (1) , 29-37

    Amputation Rehabilitation and Prosthetics Curricula in Physical Therapist Professional Education Programs.

    by Toran D MacLeod, Bradley Stockert

    Curricular guidelines do not exist currently for content related to amputation rehabilitation and prosthetics in entry-level physical therapy education programs. Documents exist to provide context, but before guidelines can be written, the current content of entry-level physical therapist professional education programs must be known. Faculty members teaching amputation rehabilitation and prosthetics at 225 accredited physical therapist education programs in the United States were recruited via e-mail. A link to the survey was emailed to faculty to report on amputation rehabilitation and prosthetics curricula, faculty qualifications, attitudes, and experiences. Faculty from 74 (32.9%) programs responded to the survey in part or whole. Faculty rated student competence on a scale of 0 (not taught), and 1 (not competent) to 5 (competent). In the areas of lower extremity amputation care, transtibial and transfemoral gait deviations, >63/68 respondents rated students 3 or greater. In contrast, 38/68 faculty rated students as <3 in the area of upper extremity amputation care, with 12 responding "not taught." Variability was noted between programs in hours of exposure, faculty-rated student competence, and minimum skill requirements. These results serve to describe the current level of training of entry-level graduates, assess and compare existing curricula, and provide guidance for further curricular development.


  • Magnetic resonance analysis of loaded meniscus deformation: a novel technique comparing participants with and without radiographic knee osteoarthritis

    by Toran D. MacLeod, Karupppasamy Subburaj, Samuel Wu, Deepak Kumar, Cory Wyatt, Richard B. Souza

    To establish a novel method of quantifying meniscal deformation using loaded MRI. More specifically, the goals were to evaluate the (1) accuracy, (2) inter-rater reliability, (3) intra-rater reliability, and (4) scan-rescan reliability. The secondary purpose of this experiment was to evaluate group differences in meniscal deformation in participants with and without radiographic knee OA.


  • Changes in the Preferred Transition Speed With Added Mass to the Foot

    by Toran D. MacLeod, Alan Hreljac, Rodney Imamura

    This study was conducted to investigate whether adding mass to subjects’ feet affects the preferred transition speed (PTS), and to ascertain whether selected swing phase variables (maximum ankle dorsiflexion angular velocity, angular acceleration, joint moment, and joint power) are determinants of the PTS, based upon four previously established criteria. After the PTS of 24 healthy active male subjects was found, using an incremental protocol in loaded (2 kg mass added to each shoe) and unloaded (shoes only) conditions, subjects walked at three speeds (60%, 80%, and 100% of PTS) and ran at one speed (100% of PTS) on a motor-driven treadmill while relevant data were collected. The PTS of the unloaded condition (2.03 ± 0.12 m/s) was significantly greater (P < .05) than the PTS of the loaded condition (1.94 ± 0.13 m/s). Within both load conditions, all dependent variables increased significantly with walking speed, decreased significantly when gait changed to a run, and were assumed to provide the necessary input to signal a gait transition, fulfilling the requirements of the first three criteria, but only ankle angular velocity reached a critical level before the transition, satisfying all four criteria to be considered a determinant of the PTS.


  • Quadriceps intramuscular fat fraction rather than muscle size is associated with knee osteoarthritis

    by D. Kumar, D.C. Karampinos, T.D. MacLeod, W. Lin, L. Nardo, X. Li, T.M. Link, S. Majumdar, R.B. Souza


  • Differences in Neuromuscular Control and Quadriceps Morphology Between Potential Copers and Noncopers Following Anterior Cruciate Ligament Injury

    by Toran D. MacLeod, Lynn Snyder-Mackler, Thomas S. Buchanan

    Study Design: Prospective cross-sectional study. Objectives: To compare knee muscle morphology and voluntary neuromuscular control in individuals who sustained an anterior cruciate ligament (ACL) injury and were identified as being capable of avoiding surgery (potential copers) and those who were recommended for surgery (noncopers), within 6 months of injury. Background: Quadriceps atrophy and poor neuromuscular control have been found in noncopers. However, the reasons why some noncopers may be able to avoid surgery remain elusive. Methods: Twenty participants (10 ACL-deficient noncopers and 10 ACL-deficient potential copers) were included in this study. Axial spin-echo, T1-weighted magnetic resonance imaging data of the lower extremities were captured. The volume and maximum cross-sectional area (CSA) of each muscle of the quadriceps and hamstrings were calculated following digital reconstruction. In addition, voluntary neuromuscular control was evaluated using an established target-matching task that required participants to produce static isometric loads across the knee joint. Electromyography was acquired from 5 muscles as participants performed the target-matching task. Circular statistics were used to calculate a specificity index to describe how well focused each muscle was activated toward its primary direction of muscle action. The ACL-deficient limb was then compared to the uninvolved limb of the noncopers and potential copers. Results: The vasti (vastus medialis and vastus intermedius) of the involved limb of the noncopers were significantly smaller (P<.031) in comparison to those of their uninvolved limb. The potential copers' vastus lateralis maximum CSA (P = .047), total quadriceps muscle volume (P = .020) and maximum CSA (P = .015), and quadriceps-hamstring ratio volume (P = .021) and maximum CSA (P = .007) demonstrated quadriceps atrophy. However, only the ACL-deficient limb of the older (mean ± SD age, 27.4 ± 11.4 versus 19.9 ± 3.3 years; P = .032) and lower-activity-level (3.3 ± 0.5 versus 3.6 ± 0.5; P = .098) noncoper group demonstrated reduced rectus femoris (P = .057) and lateral hamstring (P = .064) neuromuscular control in comparison to their uninvolved limb. Conclusion: These findings suggest that quadriceps and hamstring muscle function, rather than muscle size, may be an important factor in the varied response early after ACL injury. J Orthop Sports Phys Ther 2014;44(2):76–84. Epub 21 November 2013. doi:10.2519/jospt.2014.4876