Marcus Besser - Academia.edu (original) (raw)

Papers by Marcus Besser

Gait Posture, 1997

increaw. This will be addressed i n future study as the energy-speed relationship for these patie... more increaw. This will be addressed i n future study as the energy-speed relationship for these patients is formulated.

Foot Ankle International, Jun 1, 2009

The aim of this study was to evaluate the incidence and morphologic characteristics of osteochond... more The aim of this study was to evaluate the incidence and morphologic characteristics of osteochondral lesions of the distal tibial plafond (OLTP) by location and morphologic characteristics on MRI. We assigned 9 zones to the distal tibial plafond articular surface in an equal 3 x 3 grid configuration. Zone 1 was the most anterior and medial, zone 3 was anterior and lateral, zone 7 was most posterior and medial, and zone 9 was the most posterior and lateral. The grid was designed with all 9 zones being equal in surface area. Two observers reviewed MRI examinations of 38 patients (12 males and 26 females; mean age, 38.7 years; age range, 10 to 68 years) with reported OLTPs. We recorded the frequency of involvement and size of lesion for each zone. A chart review was performed. Of the 38 OLTP found in this study, 14 (37%) of the lesions were on the medial tibial plafond [zones 1, 4 and 7] and 11 (29%) involved the lateral tibial plafond [zones 3, 6 and 9]; 13 lesions (34%) localized to the center third of the plafond [zones 2, 5 and 8]. Nine of the lesions (24%) were on the anterior tibial plafond [zones 1, 2 and 3], 15 lesions (39%) predominately involved the posterior plafond [zones 7, 8 and 9], and 14 lesions (37%) localized to the central third of the plafond [zones 4, 5 and 6]. The medial central tibial plafond was most frequently involved site with 8 of the 38 (21%) lesions located there; the posterior medial tibial plafond was second most frequently involved with six of the 38 lesions (16%). Six of 38 ankles had both a talar osteochondral lesion and an OLTP. Of these, only one was a ;kissing' lesion. Chart review revealed that all subjects had ankle pain at time of MRI examination. We conclude that osteochondral lesions of the distal tibial plafond must be considered in the differential diagnosis of patients with symptomatic ankles and that no location had a significantly higher incidence.

Introduction The purpose of this study is to see (1) if differences exist between the gait of eld... more Introduction The purpose of this study is to see (1) if differences exist between the gait of elderly fallers and non-fallers; (2) if there is a relationship between temporal-spatial parameters and a history of falls in the elderly; and (3) whether we can use this information to predict who will fall. Our long-term goal is to be able to identify elderly individuals at risk of falling and intervene to prevent falls before they occur. Statement of Clinical Significance Approximately one-third of individuals over sixty-five years of age fall per year 3,6 . Falling is the leading cause of accidental death in those in this age group. Falls are the most common cause of injury in the elderly, resulting in over 200,000 hip fractures each year 1,7 . Over half of all elderly patients admitted to the hospital die within one year 5 . Falls are estimated to cost hospitals 2billionannuallyandindividuals,whohavefallen,morethan2 billion annually and individuals, who have fallen, more than 2billionannuallyandindividuals,whohavefallen,morethan38,000 a year 4,8 .

ABSTRACT No abstract available.

PURPOSE Our objective was to assess the utility of MRI in diagnosing injury to the Lisfranc ligam... more PURPOSE Our objective was to assess the utility of MRI in diagnosing injury to the Lisfranc ligament, and to determine whether conventional non-invasive MRI is a reliable tool for diagnosing Lisfranc joint complex instability, using manual stress radiographic evaluation under anesthesia (MSRE) and surgical findings as a reference standard. METHOD AND MATERIALS MRI exams dedicated to the midfoot at 1.5 Tesla in 21 patients with traumatic Lisfranc joint complex injury and equivocal radiographs were evaluated by two MSK radiologists. Signal and morphology of the dorsal (dC1-M2) and plantar (pC1-M2M3) bundles of the Lisfranc ligament were assessed on long and short axis sequences as was integrity of the plantar tarsal-metatarsal (pC2-M2) ligament. Fluid signal along the lateral aspect of the first metatarsal was recorded as were any regional fractures. MRI observations were correlated with MSRE/surgery findings (stable versus unstable Lisfranc joint) using logistic regression to find th...

PURPOSE Meniscal extrusion greater than 3mm has been shown to be associated with underlying tear.... more PURPOSE Meniscal extrusion greater than 3mm has been shown to be associated with underlying tear. We sought to evaluate the effect of axial load on the lower extremity for the MRI evaluation of medial meniscus extrusion in the knee. METHOD AND MATERIALS 50 patients (32F/18M, avg age 48, range 15-74) with clinical suspicion of medial meniscal tear had MR exams using a routine noncontrast knee protocol followed by repeat acquisition of sagittal PD FSE and coronal T2 FSE sequences after axial loading with an MRI compatible simulated weight-bearing device to 50% body weight. Pre and post loading sequences were evaluated by 2 MSK radiologists. Medial meniscus tears were recorded, medial meniscus extrusion (MME) was recorded and measured without and with simulated weight-bearing. Comparison between meniscus tear and non-tear groups were made. RESULTS 20 of 50 (40%) had medial meniscus tear. There was a significant difference in MME in the overall population with and without axial load; me...

BMC musculoskeletal disorders, Jan 17, 2004

The purpose of this study was to determine the test-retest reliability of temporal and spatial ga... more The purpose of this study was to determine the test-retest reliability of temporal and spatial gait measurements over a one-week period as measured using an instrumented walkway system (GAITRite). Subjects were tested on two occasions one week apart. Measurements were made at preferred and fast walking speeds using the GAITRite system. Measurements tested included walking speed, step length, stride length, base of support, step time, stride time, swing time, stance time, single and double support times, and toe in-toe out angle. Twenty-one healthy subjects participated in this study. The group consisted of 12 men and 9 women, with an average age of 34 years (range: 19-59 years). At preferred walking speed, all gait measurements had ICC's of 0.92 and higher, except base of support which had an ICC of 0.80. At fast walking speed all gait measurements had ICC's above 0.89 except base of support (ICC = 0.79), Spatial-temporal gait measurements demonstrate good to excellent test-...

Pain Medicine, 2004

Objective. To evaluate driving performance, cognition, and balance in patients with chronic nonma... more Objective. To evaluate driving performance, cognition, and balance in patients with chronic nonmalignant pain before and after the addition of transdermal fentanyl to their treatments.

Obstetrics & Gynecology, 2001

Purpose: To determine changes in foot use and foot pressure patterns during pregnancy.Methods: Th... more Purpose: To determine changes in foot use and foot pressure patterns during pregnancy.Methods: Thirteen pregnant women were enrolled in the study. At least once during each trimester, foot pressure was measured during barefoot walking using a computerized foot pressure measurement system. Morphologic structure and postural alignment of the feet were recorded. Location and severity of pain in the body and

The Journal of Bone and Joint Surgery (American), 2009

The objective of the present study was to assess the utility of magnetic resonance imaging for th... more The objective of the present study was to assess the utility of magnetic resonance imaging for the diagnosis of an injury to the Lisfranc and adjacent ligaments and to determine whether conventional magnetic resonance imaging is a reliable diagnostic tool, with manual stress radiographic evaluation with the patient under anesthesia and surgical findings being used as a reference standard. Magnetic resonance images of twenty-one feet in twenty patients (ten women and ten men with a mean age of 33.6 years [range, twenty to fifty-six years]) were evaluated with regard to the integrity of the dorsal and plantar bundles of the Lisfranc ligament, the plantar tarsal-metatarsal ligaments, and the medial-middle cuneiform ligament. Furthermore, the presence of fluid along the first metatarsal base and the presence of fractures also were evaluated. Radiographic observations were compared with intraoperative findings with respect to the stability of the Lisfranc joint, and logistic regression was used to find the best predictors of Lisfranc joint instability. Intraoperatively, seventeen unstable and four stable Lisfranc joints were identified. The strongest predictor of instability was disruption of the plantar ligament between the first cuneiform and the bases of the second and third metatarsals (the pC1-M2M3 ligament), with a sensitivity, specificity, and positive predictive value of 94%, 75%, and 94%, respectively. Nineteen (90%) of the twenty-one Lisfranc joint complexes were correctly classified on magnetic resonance imaging; in one case an intraoperatively stable Lisfranc joint complex was interpreted as unstable on magnetic resonance imaging, and in another case an intraoperatively unstable Lisfranc joint complex was interpreted as stable on magnetic resonance imaging. The majority (eighteen) of the twenty-one feet demonstrated disruption of the second plantar tarsal-metatarsal ligament, which had little clinical correlation with instability. Magnetic resonance imaging is accurate for detecting traumatic injury of the Lisfranc ligament and for predicting Lisfranc joint complex instability when the plantar Lisfranc ligament bundle is used as a predictor. Rupture or grade-2 sprain of the plantar ligament between the first cuneiform and the bases of the second and third metatarsals is highly suggestive of an unstable midfoot, for which surgical stabilization has been recommended. The appearance of a normal ligament is suggestive of a stable midfoot, and documentation of its integrity may obviate the need for a manual stress radiographic evaluation under anesthesia for a patient with equivocal clinical and radiographic examinations.

Journal of Biomechanics, 1994

Journal of Biomechanics, 1994

Gait & Posture, 1998

Abstracts / Gait R Posture 7 (1998) 157 oxygen consumptm and heart rate across harness-supported ... more Abstracts / Gait R Posture 7 (1998) 157 oxygen consumptm and heart rate across harness-supported conditmns. Statistical srgniticance was set at p = O.O( Average EMG actwty did not change stgmficantly for any of the muscle groups from FBW ta 20% BWS ambulabon. Average amplitude for the quadriceps decreased to 91.6 % ofthe FBW value. while average hams&g &d gastrocnem&u acti& decreased to 96.9 and 90 0 % ofthe FBW value, respectively. Average EMG activtty decreased sigmkicatttly from FBW to 40% BWS ambulation in the quadriceps muscles, but did not change s~gmficantly for the hamstrmg and gastrocnemious muscles. Average ampbtude for the quadriceps decreased to 72.8% of the FBW value, while hamstring and gastrocnemious activity decreased to 85 9 and 91 9 % oftbe FBW value, respectively. Oxygen consumption decreased sigmficantly from FBW to 20% BWS ambulation, decreasing by 6% from 14.3 ml/kg to I3 4 mb'kg. Oxygen consumption decreased significantly from FBW to 40% BWS ambulation, decreasmg by I?% from 14.3 ml/kg to 12 5 ml/kg Heart rate did not change s~gmficantly for any of the condmons

Gait & Posture, 1997

increaw. This will be addressed i n future study as the energy-speed relationship for these patie... more increaw. This will be addressed i n future study as the energy-speed relationship for these patients is formulated.

Gait & Posture, 1993

To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tens... more To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tensile stresses may be imposed on the surface of the plate. This condition is violated when stairs are attached to the plates, unless the plates are preloaded. Typical shear forces encountered when climbing stairs were used to determine required preloads of approximately 16.4 N/cm step height. Vertical and horizontal loads were applied at known locations on the steps, and points of application were calculated. Deviations were within l 3 mm. The effect of point of application inaccuracy on calculated joint moments is considerable. A 2 cm medial shift in the point of application resulted in calculated peak knee abduction/adduction moment errors of 35%.

Gait Posture, 1997

increaw. This will be addressed i n future study as the energy-speed relationship for these patie... more increaw. This will be addressed i n future study as the energy-speed relationship for these patients is formulated.

Foot Ankle International, Jun 1, 2009

The aim of this study was to evaluate the incidence and morphologic characteristics of osteochond... more The aim of this study was to evaluate the incidence and morphologic characteristics of osteochondral lesions of the distal tibial plafond (OLTP) by location and morphologic characteristics on MRI. We assigned 9 zones to the distal tibial plafond articular surface in an equal 3 x 3 grid configuration. Zone 1 was the most anterior and medial, zone 3 was anterior and lateral, zone 7 was most posterior and medial, and zone 9 was the most posterior and lateral. The grid was designed with all 9 zones being equal in surface area. Two observers reviewed MRI examinations of 38 patients (12 males and 26 females; mean age, 38.7 years; age range, 10 to 68 years) with reported OLTPs. We recorded the frequency of involvement and size of lesion for each zone. A chart review was performed. Of the 38 OLTP found in this study, 14 (37%) of the lesions were on the medial tibial plafond [zones 1, 4 and 7] and 11 (29%) involved the lateral tibial plafond [zones 3, 6 and 9]; 13 lesions (34%) localized to the center third of the plafond [zones 2, 5 and 8]. Nine of the lesions (24%) were on the anterior tibial plafond [zones 1, 2 and 3], 15 lesions (39%) predominately involved the posterior plafond [zones 7, 8 and 9], and 14 lesions (37%) localized to the central third of the plafond [zones 4, 5 and 6]. The medial central tibial plafond was most frequently involved site with 8 of the 38 (21%) lesions located there; the posterior medial tibial plafond was second most frequently involved with six of the 38 lesions (16%). Six of 38 ankles had both a talar osteochondral lesion and an OLTP. Of these, only one was a ;kissing' lesion. Chart review revealed that all subjects had ankle pain at time of MRI examination. We conclude that osteochondral lesions of the distal tibial plafond must be considered in the differential diagnosis of patients with symptomatic ankles and that no location had a significantly higher incidence.

Introduction The purpose of this study is to see (1) if differences exist between the gait of eld... more Introduction The purpose of this study is to see (1) if differences exist between the gait of elderly fallers and non-fallers; (2) if there is a relationship between temporal-spatial parameters and a history of falls in the elderly; and (3) whether we can use this information to predict who will fall. Our long-term goal is to be able to identify elderly individuals at risk of falling and intervene to prevent falls before they occur. Statement of Clinical Significance Approximately one-third of individuals over sixty-five years of age fall per year 3,6 . Falling is the leading cause of accidental death in those in this age group. Falls are the most common cause of injury in the elderly, resulting in over 200,000 hip fractures each year 1,7 . Over half of all elderly patients admitted to the hospital die within one year 5 . Falls are estimated to cost hospitals 2billionannuallyandindividuals,whohavefallen,morethan2 billion annually and individuals, who have fallen, more than 2billionannuallyandindividuals,whohavefallen,morethan38,000 a year 4,8 .

ABSTRACT No abstract available.

PURPOSE Our objective was to assess the utility of MRI in diagnosing injury to the Lisfranc ligam... more PURPOSE Our objective was to assess the utility of MRI in diagnosing injury to the Lisfranc ligament, and to determine whether conventional non-invasive MRI is a reliable tool for diagnosing Lisfranc joint complex instability, using manual stress radiographic evaluation under anesthesia (MSRE) and surgical findings as a reference standard. METHOD AND MATERIALS MRI exams dedicated to the midfoot at 1.5 Tesla in 21 patients with traumatic Lisfranc joint complex injury and equivocal radiographs were evaluated by two MSK radiologists. Signal and morphology of the dorsal (dC1-M2) and plantar (pC1-M2M3) bundles of the Lisfranc ligament were assessed on long and short axis sequences as was integrity of the plantar tarsal-metatarsal (pC2-M2) ligament. Fluid signal along the lateral aspect of the first metatarsal was recorded as were any regional fractures. MRI observations were correlated with MSRE/surgery findings (stable versus unstable Lisfranc joint) using logistic regression to find th...

PURPOSE Meniscal extrusion greater than 3mm has been shown to be associated with underlying tear.... more PURPOSE Meniscal extrusion greater than 3mm has been shown to be associated with underlying tear. We sought to evaluate the effect of axial load on the lower extremity for the MRI evaluation of medial meniscus extrusion in the knee. METHOD AND MATERIALS 50 patients (32F/18M, avg age 48, range 15-74) with clinical suspicion of medial meniscal tear had MR exams using a routine noncontrast knee protocol followed by repeat acquisition of sagittal PD FSE and coronal T2 FSE sequences after axial loading with an MRI compatible simulated weight-bearing device to 50% body weight. Pre and post loading sequences were evaluated by 2 MSK radiologists. Medial meniscus tears were recorded, medial meniscus extrusion (MME) was recorded and measured without and with simulated weight-bearing. Comparison between meniscus tear and non-tear groups were made. RESULTS 20 of 50 (40%) had medial meniscus tear. There was a significant difference in MME in the overall population with and without axial load; me...

BMC musculoskeletal disorders, Jan 17, 2004

The purpose of this study was to determine the test-retest reliability of temporal and spatial ga... more The purpose of this study was to determine the test-retest reliability of temporal and spatial gait measurements over a one-week period as measured using an instrumented walkway system (GAITRite). Subjects were tested on two occasions one week apart. Measurements were made at preferred and fast walking speeds using the GAITRite system. Measurements tested included walking speed, step length, stride length, base of support, step time, stride time, swing time, stance time, single and double support times, and toe in-toe out angle. Twenty-one healthy subjects participated in this study. The group consisted of 12 men and 9 women, with an average age of 34 years (range: 19-59 years). At preferred walking speed, all gait measurements had ICC's of 0.92 and higher, except base of support which had an ICC of 0.80. At fast walking speed all gait measurements had ICC's above 0.89 except base of support (ICC = 0.79), Spatial-temporal gait measurements demonstrate good to excellent test-...

Pain Medicine, 2004

Objective. To evaluate driving performance, cognition, and balance in patients with chronic nonma... more Objective. To evaluate driving performance, cognition, and balance in patients with chronic nonmalignant pain before and after the addition of transdermal fentanyl to their treatments.

Obstetrics & Gynecology, 2001

Purpose: To determine changes in foot use and foot pressure patterns during pregnancy.Methods: Th... more Purpose: To determine changes in foot use and foot pressure patterns during pregnancy.Methods: Thirteen pregnant women were enrolled in the study. At least once during each trimester, foot pressure was measured during barefoot walking using a computerized foot pressure measurement system. Morphologic structure and postural alignment of the feet were recorded. Location and severity of pain in the body and

The Journal of Bone and Joint Surgery (American), 2009

The objective of the present study was to assess the utility of magnetic resonance imaging for th... more The objective of the present study was to assess the utility of magnetic resonance imaging for the diagnosis of an injury to the Lisfranc and adjacent ligaments and to determine whether conventional magnetic resonance imaging is a reliable diagnostic tool, with manual stress radiographic evaluation with the patient under anesthesia and surgical findings being used as a reference standard. Magnetic resonance images of twenty-one feet in twenty patients (ten women and ten men with a mean age of 33.6 years [range, twenty to fifty-six years]) were evaluated with regard to the integrity of the dorsal and plantar bundles of the Lisfranc ligament, the plantar tarsal-metatarsal ligaments, and the medial-middle cuneiform ligament. Furthermore, the presence of fluid along the first metatarsal base and the presence of fractures also were evaluated. Radiographic observations were compared with intraoperative findings with respect to the stability of the Lisfranc joint, and logistic regression was used to find the best predictors of Lisfranc joint instability. Intraoperatively, seventeen unstable and four stable Lisfranc joints were identified. The strongest predictor of instability was disruption of the plantar ligament between the first cuneiform and the bases of the second and third metatarsals (the pC1-M2M3 ligament), with a sensitivity, specificity, and positive predictive value of 94%, 75%, and 94%, respectively. Nineteen (90%) of the twenty-one Lisfranc joint complexes were correctly classified on magnetic resonance imaging; in one case an intraoperatively stable Lisfranc joint complex was interpreted as unstable on magnetic resonance imaging, and in another case an intraoperatively unstable Lisfranc joint complex was interpreted as stable on magnetic resonance imaging. The majority (eighteen) of the twenty-one feet demonstrated disruption of the second plantar tarsal-metatarsal ligament, which had little clinical correlation with instability. Magnetic resonance imaging is accurate for detecting traumatic injury of the Lisfranc ligament and for predicting Lisfranc joint complex instability when the plantar Lisfranc ligament bundle is used as a predictor. Rupture or grade-2 sprain of the plantar ligament between the first cuneiform and the bases of the second and third metatarsals is highly suggestive of an unstable midfoot, for which surgical stabilization has been recommended. The appearance of a normal ligament is suggestive of a stable midfoot, and documentation of its integrity may obviate the need for a manual stress radiographic evaluation under anesthesia for a patient with equivocal clinical and radiographic examinations.

Journal of Biomechanics, 1994

Journal of Biomechanics, 1994

Gait & Posture, 1998

Abstracts / Gait R Posture 7 (1998) 157 oxygen consumptm and heart rate across harness-supported ... more Abstracts / Gait R Posture 7 (1998) 157 oxygen consumptm and heart rate across harness-supported conditmns. Statistical srgniticance was set at p = O.O( Average EMG actwty did not change stgmficantly for any of the muscle groups from FBW ta 20% BWS ambulabon. Average amplitude for the quadriceps decreased to 91.6 % ofthe FBW value. while average hams&g &d gastrocnem&u acti& decreased to 96.9 and 90 0 % ofthe FBW value, respectively. Average EMG activtty decreased sigmkicatttly from FBW to 40% BWS ambulation in the quadriceps muscles, but did not change s~gmficantly for the hamstrmg and gastrocnemious muscles. Average ampbtude for the quadriceps decreased to 72.8% of the FBW value, while hamstring and gastrocnemious activity decreased to 85 9 and 91 9 % oftbe FBW value, respectively. Oxygen consumption decreased sigmficantly from FBW to 20% BWS ambulation, decreasing by 6% from 14.3 ml/kg to I3 4 mb'kg. Oxygen consumption decreased significantly from FBW to 40% BWS ambulation, decreasmg by I?% from 14.3 ml/kg to 12 5 ml/kg Heart rate did not change s~gmficantly for any of the condmons

Gait & Posture, 1997

increaw. This will be addressed i n future study as the energy-speed relationship for these patie... more increaw. This will be addressed i n future study as the energy-speed relationship for these patients is formulated.

Gait & Posture, 1993

To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tens... more To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tensile stresses may be imposed on the surface of the plate. This condition is violated when stairs are attached to the plates, unless the plates are preloaded. Typical shear forces encountered when climbing stairs were used to determine required preloads of approximately 16.4 N/cm step height. Vertical and horizontal loads were applied at known locations on the steps, and points of application were calculated. Deviations were within l 3 mm. The effect of point of application inaccuracy on calculated joint moments is considerable. A 2 cm medial shift in the point of application resulted in calculated peak knee abduction/adduction moment errors of 35%.