Musculoskeletal Injuries in Elite Collegiate Tenpin Bowling Athletes.

CONTEXT: Collegiate tenpin bowling participation is increasing. Accordingly, the experience level of athletes participating, factors related to performance, as well as training workload and sport specialization are likely evolving. However, literature regarding injury rates remains extremely limited. The purpose of this study was to characterize injuries in collegiate tenpin bowlers. DESIGN: Retrospective cohort survey study. METHODS: Tenpin bowling athletes of top-ranked collegiate programs in the United States were invited to participate. Each participant completed an online survey to report on their injury history and additional factors of interest. Descriptive statistics were generated for participant characteristics, injury counts, and overall injury prevalence and recurrence. Chi-square tests were used to determine if overall injury prevalence and recurrence occurred by chance, and to evaluate the influence of gender and conditioning program participation on injury frequencies. RESULTS: The response rate was 40.6% (101/249; N = 101). The sample was 20.02 (1.43) years old and 54.5% female. There were a total of 235 singular and recurrent injuries reported across all body parts. Upper-extremity injuries were the most common (n = 112). Injury prevalence (87%) and recurrence (75%) were more likely than chance (χ2 > 21.3, both P < .001) and not different based on gender (χ2 ≤ 1.1, both P ≥ .33). Injuries were more frequent in the absence of a conditioning program (χ2 = 50.6, P < .001). CONCLUSIONS: Injuries and injury recurrence in elite tenpin bowlers were frequent, most common in the upper-extremity, not different based on gender, and more frequent in those without conditioning programs. Findings may serve as foundational knowledge for developing sport-specific rehabilitation and conditioning programs.

When, where, and why should we look for vestibular dysfunction in people with diabetes mellitus?

The biochemistry of diabetes mellitus results in multi-system tissue compromise that reduces functional mobility and interferes with disease management. Sensory system compromise, such as peripheral neuropathy and retinopathy, are specific examples of tissue compromise detrimental to functional mobility. There is lack of clarity regarding if, when, and where parallel changes in the peripheral vestibular system, an additional essential sensory system for functional mobility, occur as a result of diabetes. Given the systemic nature of diabetes and the plasticity of the vestibular system, there is even less clarity regarding if potential vestibular system changes impact functional mobility in a meaningful fashion. This commentary will provide insight as to when we should employ diagnostic vestibular function tests in people with diabetes, where in the periphery we should look, and why testing may or may not matter. The commentary concludes with recommendations for future research and clinical care.

Ankle plantar flexor muscle performance and patient reported outcomes in people following total ankle arthroplasty.

BACKGROUND: The purpose of this study was to prospectively evaluate ankle power generation during gait in people with total ankle arthroplasty, and examine the relationships between postoperative plantar flexor strength, ankle power, and patient outcomes. METHODS: Nineteen people with end-stage ankle arthritis who received a total ankle arthroplasty and 19 healthy matched controls participated in this case-control study. Patient reported outcomes included a region specific measure of foot function and a generic measure of physical function. Gait speed was recorded with the 6-min walk test. Isokinetic plantar flexor strength was measured with an instrumented dynamometer. Motion capture and force plate data were used to calculate peak ankle power generation during walking. Paired or independent t-tests were used to compare ankle power across time and between groups, respectively. Bivariate correlations were performed to examine the interplay of postoperative strength, ankle power, gait speed, and patient reported outcomes. FINDINGS: Ankle power was not different between the preoperative and 6-month postoperative time points (d = 0.20). Six-month postoperative ankle power was less than controls (d = 1.32). Strength, ankle power, and gait speed were directly correlated in the patient group 6-months postoperatively (r or ρ ≥ 0.47). Six-month postoperative strength and ankle power were directly correlated to select 2-year patient reported outcomes (both ρ = 0.54). INTERPRETATION: Lower than normal 6-month postoperative ankle power, which was correlated to strength, gait speed, and longer-term patient reported outcomes, suggests efforts toward improving ankle plantar flexor muscle performance may improve patient outcomes.

The Enduring Controversy of Cervicogenic Vertigo, and Its Place among Positional Vertigo Syndromes.

The idea of cervicogenic vertigo (CV) was proposed nearly a century ago, yet despite considerable scrutiny and research, little progress has been made in clarifying the underlying mechanism of the disease, developing a confirmatory diagnostic test, or devising an appropriately targeted treatment. Given the history of this idea, we offer a review geared towards understanding why so many attempts at clarifying it have failed, with specific comments regarding how CV fits into the broader landscape of positional vertigo syndromes, what a successful diagnostic test might require, and some practical advice on how to approach this in the absence of a diagnostic test.

Total ankle arthroplasty: Strength, pain, and motion.

BACKGROUND: While outcomes such as pain and ankle motion are well researched, information regarding the effect of total ankle arthroplasty on ankle plantarflexion strength is extraordinarily limited. The purpose of this study was to evaluate ankle plantarflexion strength before and after total ankle arthroplasty, and examine the interplay of pain, motion, and strength. METHODS: This prospective case-control study included 19 patients with end-stage ankle arthritis who received a total ankle arthroplasty and 19 healthy control participants matched for age, sex, and body mass index. Pain was measured with a numeric pain rating scale. Passive sagittal plane ankle range of motion (°) and isokinetic ankle plantarflexion torque (Nm/kg) at 60 and 120°/s were measured with an instrumented dynamometer. t-tests or non-parametric tests were used to evaluate outcomes across time and between groups. Bivariate correlations were performed to evaluate the interplay of postoperative pain, motion, and torque. FINDINGS: Patient pain and motion improved between the preoperative and six-month postoperative time points (d ≥ 0.7). Ankle plantarflexion torque was not different across time (d ≤ 0.5), but was lower than control group values postoperatively (d ≥ 1.4). Significant correlations between pain and motion (r = -0.48), but not torque (-0.11 ≤ r ≤ 0.13), were observed. INTERPRETATION: Unchanged following surgery, impairments in muscle performance following total ankle arthroplasty do not appear to be changed by improved pain or motion. These findings provide impetus for postoperative strengthening interventions.

Midfoot Function Before and After Total Ankle Arthroplasty.

BACKGROUND: Information regarding the effect of total ankle arthroplasty (TAA) on midfoot function is extremely limited. The purpose of this study was to characterize midfoot region motion and power during walking in people before and after TAA. METHODS: This was a prospective cohort study of 19 patients with end-stage ankle arthritis who received a TAA and 19 healthy control group participants. A motion capture and force plate system was used to record sagittal and transverse plane first metatarsal and lateral forefoot with respect to hindfoot motion, as well as sagittal plane midfoot region positive and negative peak power during walking. Parametric or nonparametric tests to examine differences and equivalence across time were conducted. Comparisons to examine differences between postoperative TAA group and control group foot function were also performed. RESULTS: Involved-limb midfoot function was not different between the preoperative and 6-month postoperative time point in the TAA group (all P ≥ .17). Equivalence testing revealed similarity in all midfoot function variables across time (all P < .05). Decreased first metatarsal and lateral forefoot motion, as well as positive peak power generation, were noted in the TAA group postoperative involved limb in comparison to the control group (all P ≤ .01). CONCLUSION: The similarity of midfoot function across time, along with differences in midfoot function in comparison to controls, suggests that TAA does not change midfoot deficits by 6 months postoperation. LEVEL OF EVIDENCE: Level II, prospective cohort study.

Use of time-to-boundary to assess postural instability and predict functional mobility in people with diabetes mellitus and peripheral neuropathy.

BACKGROUND: People with diabetes mellitus and peripheral neuropathy (DMPN) often have balance and mobility deficits. Time-to-boundary (TTB) is a parameter of postural control that combines position and velocity center of pressure data. While not previously investigated, assessment of TTB may provide new insight regarding postural control in people with DMPN. RESEARCH QUESTION: Is TTB reduced and related to a measure of mobility in people with DMPN? METHODS: Thirteen people with DMPN without fall history and 13 healthy matched controls participated in this case-control study. Participants stood in double-limb stance on a force plate. The anterior-posterior and medial-lateral center of pressure position and velocity relative to the boundaries of the base of support were used to calculate TTB (s). Lower values indicate less postural control. Time-to-failure during single-limb stance was a secondary measure of postural control. Time to complete the Timed Up and Go (TUG) was our measure of mobility. Longer TUG times correspond to decreased mobility, strength, and balance. Independent t-tests or Mann-Whitney U tests were conducted to assess group differences. Bivariate correlations between task outcomes were conducted. RESULTS: Anterior-posterior TTB and single-limb stance times were shorter in people with DMPN (p ≤  0.04). TUG times were longer in the DMPN group (p =  0.04). In the DMPN group, inverse relationships were observed between TTB and TUG (anterior-posterior R2 = .34; medial-lateral R2 = .49; both p =  0.01), but not between single-limb stance times and TTB or TUG. SIGNIFICANCE: TTB was a sensitive measure of postural control in people with DMPN. The detected relationship between TTB and TUG newly establishes TTB as a clinically meaningful indicator of balance and function. Study findings may serve to further guide balance screening and rehabilitation efforts in people with DMPN.

Overall Health and the Influence of Physical Therapy on Physical Function Following Total Ankle Arthroplasty.

BACKGROUND: The overall health and the importance of physical therapy for people following total ankle arthroplasty (TAA) have been understudied. Our purpose was to characterize the overall health of patients following TAA, and explore the frequency, influence, and patient-perceived value of physical therapy. METHODS: People who received a TAA participated in this retrospective cohort online survey study. The survey included medical history questions and items from the Patient-Reported Outcomes Measurement Information System (PROMIS) Short Forms. Seven PROMIS domains, reflecting the biopsychosocial model of care (physical, mental, social), were included to examine participant overall health status in comparison to the general population. Items regarding physical therapy participation (yes/no), number of visits, and perceived value (scale 0-10; 10 = extremely helpful) were also included. Descriptive statistics were generated for participant characteristics, PROMIS domain T scores, and physical therapy questions. The influence of participant characteristics or physical therapy visits on PROMIS domain T scores that scored below the population mean were examined with multiple linear regression or ordinal regression. RESULTS: The response rate was 61% (n=95). Average postoperative time was approximately 3 years (mean [SD]: 40.0 [35.3] months). Physical function and ability to participate in social roles and activities domain T scores were at least 1 SD below the population mean. Most patients received physical therapy (86%; 17.1 [11.0] visits) and found it helpful (7.2 [3.0]). Participant characteristics were minimally predictive of physical function and social participation T scores. Number of physical therapy visits predicted physical function T scores (P = .03). CONCLUSIONS: Most health domain scores approached the population mean. Physical therapy was perceived to have a high value, and greater visits were related to greater physical function. However, lower physical function and social participation scores suggest that postoperative care directed toward these domains could improve the value of TAA and promote overall health. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Changes in Muscle Morphology Following Gastrocnemius Recession for Achilles Tendinopathy: A Prospective Cohort Imaging Study.

Background. The purpose of this study was to evaluate changes in posterior compartment muscle volume and intramuscular fat content following gastrocnemius recession in people with Achilles tendinopathy (AT). Methods. Eight patients diagnosed with unilateral recalcitrant AT and an isolated gastrocnemius contracture participated in this prospective cohort study. Magnetic resonance imaging was performed on both limbs of each participant before and 6 months following an isolated gastrocnemius recession. Involved limb muscle volumes and fat fractions (FFs) of the medial gastrocnemius, lateral gastrocnemius, and soleus muscle were normalized to the uninvolved limb. Preoperative to postoperative comparisons were made with Wilcoxon signed-rank tests. Results. Soleus or lateral gastrocnemius muscle volumes or FFs were not significantly different between study time points. A significant difference was found in medial gastrocnemius muscle volume (decrease; P = .012) and FF (increase; P = .017). Conclusion. A major goal of the Strayer gastrocnemius recession, selective lengthening of the posterior compartment while preserving soleus muscle morphology, was supported. The observed changes isolated to the medial gastrocnemius muscle may reduce ankle plantarflexion torque capacity. Study findings may help inform selection of surgical candidates, refine anticipated outcomes, and better direct postoperative rehabilitation following gastrocnemius recession for AT.Levels of Evidence: Level IV: Prospective cohort study.

Patient reported outcomes and ankle plantarflexor muscle performance following gastrocnemius recession for Achilles tendinopathy: A prospective case-control study.

BACKGROUND: Prospective studies to guide the application of a gastrocnemius recession for Achilles tendinopathy are limited. Our aim was to prospectively evaluate patient reported outcomes and muscle performance. METHODS: Patients with unilateral recalcitrant Achilles tendinopathy who received an isolated gastrocnemius recession (n=8) and a healthy control group (n=8) were included. Patient reported outcomes, ankle power during walking and stair ascent, and the heel rise limb symmetry index (total work) were collected. RESULTS: Improvements in pain and self-reported function were observed (six months and two years). Sport participation scores reached 92% by two years. Patients demonstrated lower ankle power during stair ascent and decreased limb symmetry during heel rise six months following treatment (p≤.02). CONCLUSIONS: Study findings regarding long-term improvements in patient pain, self-reported function and sport participation, and early preservation of ankle function during walking, can help refine patient selection, anticipated outcomes, and rehabilitation strategies.

Ankle and Midfoot Power During Single-Limb Heel Rise in Healthy Adults.

Although the midfoot is recognized to have an important role in the successful performance of a single-limb heel rise, healthy heel rise performance remains primarily characterized by ankle function. The purpose of this study was to examine the contribution of midfoot region power to single-limb heel rise in healthy adults. Participants (N = 12) performed 20 single-limb heel rises. An electromagnetic motion capture system and a force plate were used to record 3-segment foot motion and ground reaction forces. Inverse dynamic calculations were performed to obtain ankle and midfoot region powers. These data were evaluated with descriptive statistics. A correlation was performed to evaluate the contribution of midfoot region power to heel height, as heel height is a clinical measure of heel-rise performance. The midfoot contributed power during single-limb heel rise (peak positive power: 0.5 [0.2] W·kg-1). Furthermore, midfoot peak power accounted for 36% of the variance in heel height (P = .04). As energy generating internal mechanisms, such as muscle activity, are attributed to power generation, midfoot tissue loading and muscle performance should be considered during clinical and modeling applications of the heel-rise task.

Feasibility of a Low-Intensity, Technology-Based Intervention for Increasing Physical Activity in Adults at Risk for a Diabetic Foot Ulcer: A Mixed-Methods Study.

BACKGROUND: Among adults with diabetes, 19-34% will develop a diabetic foot ulcer (DFU), which increases amputation risk and health care costs, and worsens quality of life. Regular physical activity, when increased gradually, may help prevent DFUs. In this mixed-methods study, we examined the feasibility of a low-intensity, technology-based behavioral intervention to increase activity in adults at risk for DFUs. METHOD: Participants at risk for a DFU (n = 12; 66% female; mean age = 59.9 years) received four in-person exercise and behavioral counseling sessions over 2-3 weeks, supplemented with use of an activity monitor (to track steps) and text messages (to reinforce behavioral strategies) for an added 8 weeks. Pre- and postintervention assessments of accelerometer measured activity, daily mobility, and glycemic control (A1C) were completed. Treatment acceptability was assessed by questionnaire and via key informant interview. RESULTS: The program appears feasible since all but one participant attended all four sessions, all used the activity monitor and all responded to text messages. Treatment acceptability (scale: 1 = very dissatisfied, 5 = extremely satisfied) was high; average item ratings were 4.79 (SD = 0.24). Participants increased their steps by an average of 881.89 steps/day (d = 0.66). A1C decreased on average by 0.33% (d = 0.23). Daily mobility did not change. Interview results suggest that participants perceived benefits from the intervention. Participant recommended improvements included providing more physical activity information, addressing pain, and intervention delivery in a podiatry clinic. CONCLUSION: Individuals at risk for a DFU might benefit from a minimally intensive, technology-based intervention to increase their physical activity. Future research comparing the intervention to usual care is warranted.

Ankle and Midfoot Power During Walking and Stair Ascent in Healthy Adults.

Ankle power dominates forward propulsion of gait, but midfoot power generation is also important for successful push-off. However, it is unclear if midfoot power generation increases or stays the same in response to propulsive activities that induce larger external loads and require greater ankle power. The purpose of this study was to examine ankle and midfoot power in healthy adults during progressively more demanding functional tasks. Multisegment foot motion (tibia, calcaneus, and forefoot) and ground reaction forces were recorded as participants (N = 12) walked, ascended a standard step, and ascended a high step. Ankle and midfoot positive peak power and positive total power, and the proportion of midfoot to ankle positive total power were calculated. One-way repeated-measures analyses of variance were conducted to evaluate differences across tasks. Main effects were found for ankle and midfoot peak and total powers (all Ps < .01), but not for the proportion of midfoot-to-ankle total power (P = .33). Ankle and midfoot power significantly increased across each task. Midfoot power increased in proportion to ankle power and in congruence to the external load of a task. Study findings may serve to inform multisegment foot modeling applications and internal mechanistic theories of normal and pathological foot function.

The prevention of diabetic foot ulceration: how biomechanical research informs clinical practice.

BACKGROUND: Implementation of interprofessional clinical guidelines for the prevention of neuropathic diabetic foot ulceration has demonstrated positive effects regarding ulceration and amputation rates. Current foot care recommendations are primarily based on research regarding the prevention of ulcer recurrence and focused on reducing the magnitude of plantar stress (pressure overload). Yet, foot ulceration remains to be a prevalent and debilitating consequence of Diabetes Mellitus. There is limited evidence targeting the prevention of first-time ulceration, and there is a need to consider additional factors of plantar stress to supplement current guidelines. OBJECTIVES: The first purpose of this article is to discuss the biomechanical theory underpinning diabetic foot ulcerations and illustrate how plantar tissue underloading may precede overloading and breakdown. The second purpose of this commentary is to discuss how advances in biomechanical foot modeling can inform clinical practice in the prevention of first-time ulceration. DISCUSSION: Research demonstrates that progressive weight-bearing activity programs to address the frequency of plantar stress and avoid underloading do not increase ulceration risk. Multi-segment foot modeling studies indicate that dynamic foot function of the midfoot and forefoot is compromised in people with diabetes. Emerging research demonstrates that implementation of foot-specific exercises may positively influence dynamic foot function and improve plantar stress in people with diabetes. CONCLUSION: Continued work is needed to determine how to best design and integrate activity recommendations and foot-specific exercise programs into the current interprofessional paradigm for the prevention of first-time ulceration in people with Diabetes Mellitus.

The prevention of diabetic foot ulceration: how biomechanical research informs clinical practice

ABSTRACT Background Implementation of interprofessional clinical guidelines for the prevention of neuropathic diabetic foot ulceration has demonstrated positive effects regarding ulceration and amputation rates. Current foot care recommendations are primarily based on research regarding the prevention of ulcer recurrence and focused on reducing the magnitude of plantar stress (pressure overload). Yet, foot ulceration remains to be a prevalent and debilitating consequence of Diabetes Mellitus. There is limited evidence targeting the prevention of first-time ulceration, and there is a need to consider additional factors of plantar stress to supplement current guidelines. Objectives The first purpose of this article is to discuss the biomechanical theory underpinning diabetic foot ulcerations and illustrate how plantar tissue underloading may precede overloading and breakdown. The second purpose of this commentary is to discuss how advances in biomechanical foot modeling can inform clinical practice in the prevention of first-time ulceration. Discussion Research demonstrates that progressive weight-bearing activity programs to address the frequency of plantar stress and avoid underloading do not increase ulceration risk. Multi-segment foot modeling studies indicate that dynamic foot function of the midfoot and forefoot is compromised in people with diabetes. Emerging research demonstrates that implementation of foot-specific exercises may positively influence dynamic foot function and improve plantar stress in people with diabetes. Conclusion Continued work is needed to determine how to best design and integrate activity recommendations and foot-specific exercise programs into the current interprofessional paradigm for the prevention of first-time ulceration in people with Diabetes Mellitus.

Ankle Power and Endurance Outcomes Following Isolated Gastrocnemius Recession for Achilles Tendinopathy.

BACKGROUND: Studies have demonstrated improved ankle dorsiflexion and pain reduction following a gastrocnemius recession (GR) procedure. However, changes in muscle performance during functional activities are not known. The purpose of this study was to determine the effect of an isolated GR on ankle power and endurance in patients with Achilles tendinopathy. METHODS: Fourteen patients with chronic unilateral Achilles tendinopathy and 10 healthy controls participated in this study. Patient group data were collected 18 months following GR. Pain was compared to preoperative values using a 10-cm visual analog scale (VAS). Patient-reported outcomes for activities of daily living (ADL) and sports were assessed using the Foot and Ankle Ability Measure (FAAM). Kinematic and kinetic data were collected during gait, stair ascent (standard and high step), and repetitive single-limb heel raises. Between-group and side-to-side differences in ankle plantarflexor muscle power and endurance were evaluated with appropriate t tests. RESULTS: Compared with preoperative data, VAS pain scores were reduced (pre 6.8, post 1.6, P < .05). Significant differences were observed between GR and Control groups for FAAM scores for both ADL (GR 90.0, Control 98.3, P = .01) and Sports subscales (GR 70.6, Control 94.6, P = .01). When compared to controls, ankle power was reduced in the involved limb of the GR group for all activities (all P < .05). Between-group and side-to-side deficits (GR group only) were also found for ankle endurance. CONCLUSION: The gastrocnemius recession procedure provided significant pain reduction that was maintained at the 18-month follow-up for patients with chronic Achilles tendinopathy who failed nonoperative interventions. There were good patient-reported outcomes for activities of daily living. However, compared to controls, ankle plantarflexion power and endurance deficits in the GR group were noted. The functional implications of the muscle performance deficits are unclear, but may be reflective of patients' self-reported difficulty during more challenging activities. LEVEL OF EVIDENCE: Level III, comparative study.

Multi-joint foot kinetics during walking in people with Diabetes Mellitus and peripheral neuropathy.

Neuropathic tissue changes can alter muscle function and are a primary reason for foot pathologies in people with Diabetes Mellitus and peripheral neuropathy (DMPN). Understanding of foot kinetics in people with DMPN is derived from single-segment foot modeling approaches. This approach, however, does not provide insight into midfoot power and work. Gaining an understanding of midfoot kinetics in people with DMPN prior to deformity or ulceration may help link foot biomechanics to anticipated pathologies in the midfoot and forefoot. The purpose of this study was to evaluate midfoot (MF) and rearfoot (RF) power and work in people with DMPN and a healthy matched control group. Thirty people participated (15 DMPN and 15 Controls). An electro-magnetic tracking system and force plate were used to record multi-segment foot kinematics and ground reaction forces during walking. MF and RF power, work, and negative work ratios were calculated and compared between groups. Findings demonstrated that the DMPN group had greater negative peak power and reduced positive peak power at the MF and RF (all p≤0.05). DMPN group negative work ratios were also greater at the MF and RF [Mean difference MF: 9.9%; p=0.24 and RF: 18.8%; p<0.01]. In people with DMPN, the greater proportion of negative work may negatively affect foot structures during forward propulsion, when positive work and foot stability should predominate. Further study is recommended to determine how both MF and RF kinetics influence the development of deformity and ulceration in people with DMPN.

Individual metatarsal and forefoot kinematics during walking in people with diabetes mellitus and peripheral neuropathy.

The purpose of this study was to compare in-vivo kinematic angular excursions of individual metatarsal segments and a unified forefoot segment in people with Diabetes Mellitus and peripheral neuropathy (DMPN) without deformity or ulceration to a healthy matched control group. Thirty subjects were recruited. A five- segment foot model (1st, 3rd, and 5th metatarsals, calcaneus, tibia) was used to examine relative 3D angular excursions during the terminal stance phase of walking. Student t-tests were used to assess group differences in kinematics. Pearson correlations and cross-correlations were used to assess relationships between the motion of the individual metatarsals and the unified forefoot. Significant reductions of DMPN group sagittal plane angular excursions were detected in all individual metatarsals and the unified forefoot (p < 0.01). Frontal plane 3rd metatarsal excursion was reduced (p = 0.04) in the DMPN group. The 3rd and 5th metatarsal and the unified forefoot excursions were reduced (p ≤ 0.02) in the DMPN group in the transverse plane. In both groups, coupling of individual metatarsal and unified forefoot motion was strongest in the sagittal plane. This study illustrates that multiple individual metatarsals have reduced motion in people with DMPN. Differences in the magnitude and coupling between individual metatarsal motion and unified forefoot motion supports the use of a two segment forefoot modeling approach in future kinematic analyses. Further study is recommended to determine if the observed kinematic profile is related to the development and location of deformity and tissue breakdown in people with DMPN.

Alterations in plantar pressure with different walking boot designs.

BACKGROUND: Specialized walking devices, such as total contact casts and removable walking boots, have been shown to be effective noninvasive treatment options for plantar ulcers. Attempts at improving patient compliance frequently lead to new boot designs; however, the effect of the design modifications on plantar pressures or on the contralateral limb often is unknown. The purpose of this study was to determine the effect of different walking-boot calf heights and rocker sole designs on regional plantar pressures, as well as, on contralateral limb loading during walking. METHODS: Twenty-six subjects, 20 to 54 years of age, without foot pathology were tested using four different configurations: high calf, rocker sole (HCR); low calf, rocker sole (LCR); low calf, modified rocker sole (LCMR), and shoe. Peak pressures, pressure-time integrals, and contact areas were measured using the Novel Pedar-X insole pressure measurement system. Average peak force was calculated for the contralateral limb. RESULTS: Greatest forefoot peak pressure reduction was found in the HCR group (37.3% reduction compared to shoe condition), followed by 31.6% and 19.8% in the LCR and LCMR groups, respectively (p<0.0001). Forefoot pressure-time integrals were reduced for HCR and LCR (22.1% and 21.5%, respectively) compared to the LCMR (13.0%) (p<0.0001). CONCLUSIONS: Isolated modifications in walking boot designs resulted in plantar pressure modifications. LCR and LCMR designs favorably altered plantar pressures, but of a lesser magnitude than the HCR design. If lower calf, lower sole walking boot designs are recommended because of anticipated improvement in patient compliance, healing times may be prolonged.