Choosing Among 3 Ankle-Foot Orthoses for a Patient With Stage II Posterior Tibial Tendon Dysfunction

No head-to-head comparisons of different orthoses for patients with stage II posterior tibial tendon dysfunction (PTTD) have been performed to date. Additionally, the cost of orthoses varies considerably, thus choosing an effective orthosis that is affordable to the patient is largely a trial-and-error process. Case Description: A 77-year-old woman was seen with complaints of abnormal foot posture (“my foot is out”), minimal medial foot and ankle pain, and a 3-year history of conservatively managed stage II PTTD. The patient was not able to complete 1 single-limb heel rise on the involved side, while she could complete 3 on the uninvolved side. Ankle strength testing revealed a mild to moderate loss of plantar flexor strength (20%–31% deficit on the involved side), combined with a 22% deficit in isometric ankle inversion and forefoot adduction strength. To assist this patient in managing her flatfoot posture and PTTD, 3 orthoses were considered: an off-the-shelf ankle-foot orthosis (AFO), a custom solid AFO, and a custom articulated AFO. The patient\u27s chief complaint was partly cosmetic (“my foot is out”). As decreasing flatfoot kinematics may unload the tibialis posterior muscle, thus prevent the progression of foot deformity, the primary goal of orthotic intervention was to improve flatfoot kinematics. Given the difficulties in clinical approaches to evaluating flatfoot kinematics, a quantitative gait analysis, using a multisegment foot model, was used. Outcomes in the frontal plane, all 3 orthoses were associated with small changes toward hindfoot inversion. In the sagittal plane, between 2.7° and 6.1°, greater forefoot plantar flexion (raising the medial longitudinal arch) occurred. There were no differences among the orthoses on hindfoot inversion and forefoot plantar flexion. In the transverse plane, the off-the-shelf design was associated with forefoot abduction, the custom solid orthosis was associated with no change, and the custom articulated orthosis was associated with forefoot adduction. Discussion based on gait analysis, the higher-cost custom articulated orthosis was chosen as optimal for the patient. This custom articulated orthosis was associated with the greatest change in flatfoot deformity, assessed using gait analysis. The patient felt it produced the greatest correction in foot deformity. Reducing flatfoot deformity while allowing ankle movement may limit progression of stage II PTTD

Midfoot Power During Walking and Stair Ascent in Healthy Adults

Introduction/Purpose: Intrinsic foot muscles have the capacity to attenuate and reverse arch deformation under loaded conditions. This function is proposed to be an important component in generating the midfoot power and stability requisite for gastroc-soleus muscle action at the ankle during forward propulsion. Synergistic activation of intrinsic foot muscles is proposed to function as a ‘foot core’ during weightbearing activity that is analogous to the function of the smaller muscles at the spine. If this theory were sound, midfoot power would be expected to increase, potentially in proportion to ankle power, as the muscular demand of a task increases. The purpose of this study was to explore the nature and behavior of midfoot and ankle power during walking and stair ascent in healthy adults

Giving Way Event During a Combined Stepping and Crossover Cutting Task in an individual with Anterior Cruciate Ligament Deficiency

Study Design: Case study. Objective: To compare knee kinematics and moments of nongiving way trials to a giving way trial during a combined stepping and crossover cutting activity. Background: The knee kinematics and moments associated with giving way episodes sugge motor control strategies that lead to instability and recovery of stability during movement. Methods and Measures: A 27-year-old woman with anterior cruciate ligament deficiency reported giving way while performing a combined stepping and crossover cutting activity. P motion analysis system recorded motion of the pelvis, femur, tibia, and foot using 3 infrarec emitting diodes placed on each segment at 60 Hz. Force plate recordings at 300 Hz were combined with limb inertial properties and position data to estimate net knee joint moments. The stance time, foot progression angle, and cutting angle were also included to evaluate performance between trials. Results: Knee internal rotation during the giving way trial increased 3.2\u27 at 54% of stance relative to the nongiving way trials. Knee flexion during the giving way trial increased to 33.1 at 66% of stance, and the knee moment switched from a nominal flexor moment to 2 knee extensor moment at 64% of stance. The knee abductor moment and external rotation moment during the giving way trial deviated in early stance. Conclusions: The observed response to the giving way event suggests that increasing knee flexion may enhance knee stability for this subject. The transverse and frontal plane moments appear important in contributing to the giving way event. Further research that assists clinicians in understanding how interventions can impact control of movements in these planes is necessary

Variations in the Relationship Between the Frequency Content of EMG Signals and the Rate of Torque Development in Voluntary and Elicited Contractions

Our purpose was to characterize the relationship between EMG mean power frequency (MPF) or median frequency (MF) and rate of torque development in voluntary ballistic and electrically elicited isometric contractions. Twenty-three healthy adults participated in two sets of experiments performed on elbow flexor muscles. For Experiment 1, subjects were asked to generate voluntary ballistic contractions by reaching four different target torque levels (20, 40, 60 and 100% of the maximal voluntary contraction (MVC)) as fast as they could. For Experiment 2, electrical (M-waves) and mechanical (twitches) responses to electrical stimulation of the nerves supplying the biceps brachii and brachioradialis muscles were recorded with the subjects at rest and with a background isometric contraction of 15% MVC. MPF, MF and rate of torque development (% MVC/s) were calculated for both voluntary and elicited contractions. Significant positive correlations were observed between MPF and rate of torque development for the voluntary contractions, whereas significant negative correlations were observed between the two variables for elicited contractions. This suggests that factors other than muscle fiber composition influence the frequency content of EMG signals and/or the rate of torque development, and that the effect of these factors will vary between voluntary and elicited contractions. 2002 Elsevier Science Ltd. All rights reserved

Can Foot Exercises and Barefoot Weight Bearing Improve Foot Function in Participants with Flat Feet?

Background: Unexplored in individuals with flatfoot (FF) is the potential of foot specific exercise and barefoot weightbearing (BWB) to improve foot function. The purposes of this study were A. To evaluate whether exercise and BWB alter foot muscle structure in participants with FF B. To evaluate whether exercise and BWB alters foot and ankle function in participants with FF C. To compare foot muscle structure and foot and ankle function between participants with FF to controls with neutral foot posture prior to exercise. Methods: Twenty participants with FF and 12 participants with neutral foot posture participated. Participants with FF completed 8 weeks of 4 foot exercises and 2 hours of BWB. Pre and post-exercise tests included: A. Diagnostic ultrasound to quantify abductor hallucis cross sectional area (CSA) B. Embedded force plates to assess paper grip test (PGT) force C. Heel rise height and repetitions D. The Foot and Ankle Ability Measure (FAAM), and qualitative data to capture potential benefits post-exercise.Control and FF data was compared pre-exercisewith independent t-tests. Two-way repeated measures ANOVA’s were used to compare participants with FF pre and post-exercise. The effect size index (ESI) was used to note the degree of improvement. Results: Participants with FF significantly improved in all variables except the FAAM. Muscle CSA increased from 0.27cm2 to 0.35cm2, a 12.9- 16.7% increase (P\u3c0.05).The PGT showed increased force post-exercise from 13.2N to 13.7N (P\u3c0.05). Post-exercise heel rise repetitions increased from 7.1-7.6 repetitions (P\u3c0.05).Compliance was 87.7% of prescribed exercises and 111% of time targeted for BWB. Conclusion: Foot specific exercises and BWB achieve sufficient training intensity to result in changes in foot function. The study confirms that training effects specific to the foot are achievable in participants with FF, and likely to patients with foot problems

Can Patient Reported Outcomes Guide Therapy Needs in Foot and Ankle Patients?

Introduction/Purpose: The patient acceptable symptom state (PASS) is a validated question establishing if patients activity and symptoms are at a satisfactory low level for pain and function. Surprisingly, ~20% of foot and ankle patients at their initial visit present for care with an acceptable symptom state (i.e. PASS yes). These patients are important to identify to prevent over treatment and avoid excessive cost. It is also unclear what health domains (Pain Interference (PI), Physical Function (PF), or Depression (Dep)) influence a patients judgement of their PASS state (i.e. why they are seeking treatment). The purpose of this analysis is to document the prevalance of PASS state and determine the health domains that discriminate PASS patients and predict PASS state at the initiation of rehabilitation

Do Patients Judge Success of Treatment and Patient Acceptable Symptom State Based on Current Self-Reported Health Status?

Background: Value-based care models call for better interpretation of patient-reported outcomes. Patients may reference health status differently when appraising if an intervention was successful versus if their current state is acceptable. The purpose of this study was to determine the association between success of treatment (SOT), patient acceptable symptom state (PASS), and PROMIS measure T-scores, following a single primary care physical therapy encounter. Methods: Cross-sectional study. Ninety-two patients with musculoskeletal complaints were administered standard SOT and PASS questions, and PROMIS Physical Function, Pain Interference, and Self-Efficacy for Managing Symptoms measures. Association of PASS and SOT was determined using rank biserial correlation and chi-squared analysis. Accuracy of PROMIS T-scores to discriminate PASS and SOT was determined through receiver-operator curve analysis and likelihood ratios. Results: There was significant association between PASS and SOT (r=.393, p\u3c0.001; X2=15.7, p=0.001). The three PROMIS measures discriminated PASS with AUCs of 0.73 to 0.88 (accuracy 67.3% to 82.6%), Self-Efficacy being the strongest discriminator. Only Pain Interference T-scores discriminated SOT with AUC \u3e0.70 (accuracy 76.1%). Conclusion: PASS was more strongly associated with health status than SOT. Patients make a meaningful distinction between these two questions. Accurate clinician interpretation of PASS, SOT, and PROMIS T-scores can allow more targeted goal setting and treatment decision making

Reading the Future: Predicting Who Will Benefit from Bunion Surgery

Introduction/Purpose: Hallux valgus is a common condition of the foot with 4.4 million patients seeking care yearly for this condition. A previous study suggested specific pre-operative cut-off scores based on Patient Reported Outcomes Measurement Information System (PROMIS) physical function (PF), pain interference (PI), and depression (D) values could predict post-operative outcomes in foot and ankle surgery. Though hallux valgus correction, among other procedures, were identified as one of the most common surgeries in the previous study, specific conditions were not considered separately. The purpose of this study was to evaluate the validity of applying a published comprehensive pre-surgical PROMIS profile of PF, PI and D to patients undergoing bunionectomy surgery

Does Identifying Provider Expectations Improve Adoption of Patient Reported Outcomes?

Introduction/Purpose: New instruments like the Patient Reported Outcome Information System (PROMIS) minimize the burden to patients and providers addressing significant barriers to adoption. Despite these advances provider adoption remains lackluster. Models of technology adoption suggest adoption is more likely to occur when PRO’s directly improve patient care (performance expectancy) and it’s easy to implement (effort expectancy). Problems with effort expectancy are dealt with by training and improving logistics (i.e. eHR presentation, alerts), where performance expectancy is addressed through research (i.e. validation of thresholds). The purposes of this study were to: 1) evaluate the proportion of orthopedic rehabilitation providers who use PRO’s and how they use them; And, 2) to determine if performance expectancy, effort expectancy or provider burnout are related to provider use

The Road to Recovery for Bunion Surgery: Data Analytic Plots to Target Patient Progress

Introduction/Purpose: Patient reported outcomes (PROs) can provide information on individual patient’s progress throughout a treatment course and additionally, with common surgeries, powerful numbers can be generated to provide data analytic curves to provide a recovery road map for patients and surgeons. Those who deviate negatively from the predicted path may have a complication and early intervention can be initiated. Those who deviate positively have the potential to need less physical therapy, early return to sports or work. Hallux valgus (HV) is a common condition of the foot with 4.4 million patients seeking care yearly and surgery is equally common. The purpose of this study was to determine if PROMIS PROs can be used to construct data analytic curves for HV surgery