The Design and Validation of a Low-Cost Foot Measurement System.

It is estimated that approximately 40% of the population suffers from abnormal foot posture, specifically high arched or low arched feet. While the evaluation of foot posture can involve many aspects, it commonly requires the measurement of basic dimensions of the foot. Clinicians and researchers often rely on the use of specialized devices or three-dimensional (3D) scanners to evaluate specific aspects of a patient's foot posture. However, current technologies are extremely expensive, therefore highlighting the need for a cost-effective device to be used in rural and clinical settings. As a result, the purpose of this study was to develop an inexpensive system to measure total foot length, truncated length, dorsum height, navicular height, and foot width. Bland-Altman plots showed significant differences between this measurement system and a 3D scanner for total foot length, truncated length, and navicular height (p < 0.001) and significant differences when assessing the repeatability of dorsum height (p = 0.022). However, the magnitudes of these differences were minimal compared to the overall measurement. Additionally, interclass correlation coefficients revealed that this system had excellent validity when compared to a 3D scanner (interclass correlation coefficients = 0.908-0.994), and good to excellent repeatability when compared between days (interclass correlation coefficients = 0.867-0.996). These results demonstrate that it is possible to design an inexpensive, valid, and repeatable system that can be used in clinical, research, and rural settings to successfully evaluate basic dimensions of the foot that can be used for the determination of foot type.

Gait Analysis Reveals that Total Hip Arthroplasty Increases Power Production in the Hip During Level Walking and Stair Climbing.

BACKGROUND: total hip arthroplasty (THA) is associated with decreased pain and improved function, including increased walking speed, but it does not always improve overall joint mechanics during activities of daily living such as level walking and stair climbing. The hip's ability to generate power to move and allow for smooth and efficient forward motion is critical to success after surgery. Although osteoarthritis (OA) of the hip limits the power of the affected joint, it is not known whether other joints in the affected limb or in the contralateral limb need to produce more power to compensate. Additionally, it is not known whether alterations in the production of power before and after surgery are gender-specific. QUESTIONS/PURPOSES: (1) Is there a change in the power production of the bilateral ankles, knees, and hips during level walking before and after patients undergo unilateral THA, and are there important gender-specific differences in these findings? (2) How do these findings differ for stair climbing? METHODS: Three-dimensional motion and ground reaction force data were collected for 13 men and 13 women who underwent primary, unilateral THA. This was a secondary analysis of previously collected data on gait mechanics from 60 patients who underwent THA. In the initial study, patients were included if they were scheduled to undergo a primary, unilateral THA within 4 weeks of the study and were able to walk without an assistive device. Patients were recruited from the practices of four surgeons at a single institution from 2008 to 2011. Patients were included in the current study if they were enrolled in the previous study, attended all three assessment visits (preoperative and 6 weeks and 1 year postoperative), and, during the preoperative visit, were able to walk without using an assistive device and climb stairs without using a handrail. Patients walked and ascended stairs at a self-selected speed at the three assessment visits. The power of each ankle, knee, or hip was calculated in Visual 3D using kinematic and kinetic data collected using motion capture. Power for each joint was normalized to the total power of the bilateral lower limbs by dividing the individual joint power by the total lower-extremity joint power. A mixed-model repeated-measures ANOVA was used to determine differences in normalized joint power for the ankle, knee, and hip, based on gender, limb (surgical-side versus nonsurgical-side) and timepoint (preoperative and 6 weeks and 1 year postoperative). RESULTS: Surgical-side absolute (preoperative: -0.2 ± 0.2 [CI, -0.3 to -0.2], 1 year postoperative: -0.5 ± 0.3 [CI, -0.6 to - 0.5]; p < 0.001) and normalized (preoperative: 0.05 ± 0.04 [CI, 0.03-0.06], 1 year postoperative: 0.08 ± 0.04 [CI, 0.06-0.09]; p = 0.020) hip power production increased during walking. Surgical-side absolute (preoperative: 1.1 ± 0.3 [CI, 1.0-1.3], 1 year postoperative: 1.6 ± 0.2 [CI, 1.3-2.0]; p = 0.005) and normalized (preoperative: 0.16 ± 0.04 [CI, 0.14-0.18], 1 year postoperative: 0.21 ± 0.06 [CI, 0.18-0.24]; p = 0.008) hip power production increased during stair climbing, while nonsurgical ankle absolute (preoperative: 0.9 ± 0.5 [CI, 0.6 - 1.2], 1 year postoperative: 0.6 ± 0.3 [CI, 0.4-0.8]; p = 0.064) and normalized (preoperative: 0.13 ± 0.06 [CI, 0.10-0.16], 1 year postoperative: 0.08 ± 0.04 [CI, 0.06-0.10]; p = 0.015) power decreased during stair climbing after THA. No consistent effect of gender was observed. CONCLUSIONS: In this gait-analysis study, power was improved in hip joints that were operated on, and power production in the ipsilateral and contralateral ankles and ipsilateral hips was reduced during level walking and stair climbing. The success of surgical intervention must be based on restoring reasonable balance of forces in the lower limb. Patients with OA of the hip lose power production in this joint and must compensate for the loss by producing power in other joints, which then may become arthritic. To determine future interventions, an understanding of whether changes in forces or joint angle affect the change in joint power is needed. Based on these results, THA appeared to effectively increase hip power and reduce the need for compensatory power production in other joints for both men and women in this patient cohort. LEVEL OF EVIDENCE: Level I, prognostic study.

The Reliability and Validity of the Loadsol® under Various Walking and Running Conditions.

The assessment of loading during walking and running has historically been limited to data collection in laboratory settings or with devices that require a computer connection. This study aims to determine if the loadsol®-a single sensor wireless insole-is a valid and reliable method of assessing force. Thirty (17 male and 13 female) recreationally active individuals were recruited for a two visit study where they walked (1.3 m/s) and ran (3.0 and 3.5 m/s) at a 0%, 10% incline, and 10% decline, with the visits approximately one week apart. Ground reaction force data was collected on an instrumented treadmill (1440 Hz) and with the loadsol® (100 Hz). Ten individuals completed the day 1 protocol with a newer 200 Hz loadsol®. Intraclass correlation coefficients (ICC3,k) were used to assess validity and reliability and Bland⁻Altman plots were generated to better understand loadsol® validity. Across conditions, the peak force ICCs ranged from 0.78 to 0.97, which increased to 0.84⁻0.99 with the 200 Hz insoles. Similarly, the loading rate ICCs improved from 0.61 to 0.97 to 0.80⁻0.96 and impulse improved from 0.61 to 0.97 to 0.90⁻0.97. The 200 Hz insoles may be needed for loading rate and impulse in running. For both walking and running, the loadsol® has excellent between-day reliability (>0.76).

Statistical Parametric Mapping as a Measure of Differences Between Limbs: Applications to Clinical Populations.

In healthy individuals, symmetrical lower-extremity movement is often assumed and calculated using discrete points during various tasks. However, measuring overall movement patterns using methods such as statistical parametric mapping (SPM) may allow for better interpretation of human movement. This study demonstrated the ability of SPM to assess interlimb differences in lower-extremity movement during 2 example tasks: running and landing. Three-dimensional motion analysis was used to determine sagittal and frontal plane lower-extremity joint angles in (1) young and older individuals during running and (2) patients with anterior cruciate ligament reconstruction and uninjured control athletes during landing. Interlimb differences within each group were compared using SPM and paired t tests on peak discrete angles. No differences between limbs were found between young and older runners using SPM. Peak ankle eversion and plantar flexion angles differed between limbs in young and older runners. Sagittal plane hip angle varied between limbs in uninjured control athletes. Frontal plane ankle angle and sagittal plane knee and hip angles differed between limbs in patients with anterior cruciate ligament reconstruction using SPM and discrete analysis. These data suggest that SPM can be useful to determine clinically meaningful interlimb differences during running and landing in multiple populations.

Validity and Repeatability of Single-Sensor Loadsol Insoles during Landing.

Clinically feasible methods for quantifying landing kinetics could help identify patients at risk for secondary anterior cruciate ligament injuries. The purpose of this study was to evaluate the validity and between-day repeatability of the loadsol insole during a single-hop and bilateral stop-jump. Thirty healthy recreational athletes completed seven single-hops and seven stop-jumps while simultaneous loadsol (100 Hz) and force plate (1920 Hz) measurements were recorded. Peak impact force, loading rate, and impulse were computed for the dominant limb, and limb symmetry was calculated between limbs for each measure. All outcomes were compared between the loadsol and force plate using intraclass correlation coefficients (ICC) and Bland⁻Altman plots. Fifteen participants completed a second day of testing to assess between-day repeatability of the loadsol. Finally, an additional 14 participants completed the first day of testing only to assess the validity of the newest generation loadsol, which sampled at 200 Hz. At 100 Hz, validity ICC results were moderate to excellent (0.686⁻0.982), and repeatability ICC results were moderate to excellent (0.616⁻0.928). The 200 Hz loadsol demonstrated improved validity ICC (0.765⁻0.987). Bland⁻Altman plots revealed that the loadsol underestimated load measures. However, this bias was not observed for symmetry outcomes. The loadsol device is a valid and repeatable tool for evaluating kinetics during landing.

Are There Differences in Gait Mechanics in Patients With A Fixed Versus Mobile Bearing Total Ankle Arthroplasty? A Randomized Trial.

BACKGROUND: Total ankle arthroplasty (TAA) is an alternative to arthrodesis, but no randomized trial has examined whether a fixed bearing or mobile bearing implant provides improved gait mechanics. QUESTIONS/PURPOSES: We wished to determine if fixed- or mobile-bearing TAA results in a larger improvement in pain scores and gait mechanics from before surgery to 1 year after surgery, and to quantify differences in outcomes using statistical analysis and report the standardized effect sizes for such comparisons. METHODS: Patients with end-stage ankle arthritis who were scheduled for TAA between November 2011 and June 2013 (n = 40; 16 men, 24 women; average age, 63 years; age range, 35-81 years) were prospectively recruited for this study from a single foot and ankle orthopaedic clinic. During this period, 185 patients underwent TAA, with 144 being eligible to participate in this study. Patients were eligible to participate if they were able to meet all study inclusion criteria, which were: no previous diagnosis of rheumatoid arthritis, a contralateral TAA, bilateral ankle arthritis, previous revision TAA, an ankle fusion revision, or able to walk without the use of an assistive device, weight less than 250 pounds (114 kg), a sagittal or coronal plane deformity less than 15°, no presence of avascular necrosis of the distal tibia, no current neuropathy, age older than 35 years, no history of a talar neck fracture, or an avascular talus. Of the 144 eligible patients, 40 consented to participate in our randomized trial. These 40 patients were randomly assigned to either the fixed (n = 20) or mobile bearing implant group (n = 20). Walking speed, bilateral peak dorsiflexion angle, peak plantar flexion angle, sagittal plane ankle ROM, peak ankle inversion angle, peak plantar flexion moment, peak plantar flexion power during stance, peak weight acceptance, and propulsive vertical ground reaction force were analyzed during seven self-selected speed level walking trials for 33 participants using an eight-camera motion analysis system and four force plates. Seven patients were not included in the analysis owing to cancelled surgery (one from each group) and five were lost to followup (four with fixed bearing and one with mobile bearing implants). A series of effect-size calculations and two-sample t-tests comparing postoperative and preoperative increases in outcome variables between implant types were used to determine the differences in the magnitude of improvement between the two patient cohorts from before surgery to 1 year after surgery. The sample size in this study enabled us to detect a standardized shift of 1.01 SDs between group means with 80% power and a type I error rate of 5% for all outcome variables in the study. RESULTS: This randomized trial did not reveal any differences in outcomes between the two implant types under study at the sample size collected. In addition to these results, effect size analysis suggests that changes in outcome differ between implant types by less than 1 SD. Detection of the largest change score or observed effect (propulsive vertical ground reaction force [Fixed: 0.1 ± 0.1; 0.0-1.0; Mobile: 0.0 ± 0.1; 0.0-0.0; p = 0.0.051]) in this study would require a future trial to enroll 66 patients. However, the smallest change score or observed effect (walking speed [Fixed: 0.2 ± 0.3; 0.1-0.4; Mobile: 0.2 ± 0.3; 0.0-0.3; p = 0.742]) requires a sample size of 2336 to detect a significant difference with 80% power at the observed effect sizes. CONCLUSIONS: To our knowledge, this is the first randomized study to report the observed effect size comparing improvements in outcome measures between fixed and mobile bearing implant types. This study was statistically powered to detect large effects and descriptively analyze observed effect sizes. Based on our results there were no statistically or clinically meaningful differences between the fixed and mobile bearing implants when examining gait mechanics and pain 1 year after TAA. LEVEL OF EVIDENCE: Level II, therapeutic study.

Biomarkers in Sports and Exercise: Tracking Health, Performance, and Recovery in Athletes.

Biomarker discovery and validation is a critical aim of the medical and scientific community. Research into exercise and diet-related biomarkers aims to improve health, performance, and recovery in military personnel, athletes, and lay persons. Exercise physiology research has identified individual biomarkers for assessing health, performance, and recovery during exercise training. However, there are few recommendations for biomarker panels for tracking changes in individuals participating in physical activity and exercise training programs. Our approach was to review the current literature and recommend a collection of validated biomarkers in key categories of health, performance, and recovery that could be used for this purpose. We determined that a comprehensive performance set of biomarkers should include key markers of (a) nutrition and metabolic health, (b) hydration status, (c) muscle status, (d) endurance performance, (e) injury status and risk, and (f) inflammation. Our review will help coaches, clinical sport professionals, researchers, and athletes better understand how to comprehensively monitor physiologic changes, as they design training cycles that elicit maximal improvements in performance while minimizing overtraining and injury risk.

Concussion History and Time Since Concussion Do not Influence Static and Dynamic Balance in Collegiate Athletes.

CONTEXT: Dynamic balance deficits exist following a concussion, sometimes years after injury. However, clinicians lack practical tools for assessing dynamic balance. OBJECTIVES: To determine if there are significant differences in static and dynamic balance performance between individuals with and without a history of concussion. DESIGN: Cross sectional. SETTING: Clinical research laboratory. PATIENTS OR OTHER PARTICIPANTS: 45 collegiate student-athletes with a history of concussion (23 males, 22 females; age = 20.0 ± 1.4 y; height = 175.8 ± 11.6 cm; mass = 76.4 ± 19.2 kg) and 45 matched controls with no history of concussion (23 males, 22 females; age = 20.0 ± 1.3 y; height = 178.8 ± 13.2 cm; mass = 75.7 ± 18.2 kg). INTERVENTIONS: Participants completed a static (Balance Error Scoring System) and dynamic (Y Balance Test-Lower Quarter) balance assessment. MAIN OUTCOME MEASURES: A composite score was calculated from the mean normalized Y Balance Test-Lower Quarter reach distances. Firm, foam, and overall errors were counted during the Balance Error Scoring System by a single reliable rater. One-way ANOVAs were used to compare balance performance between groups. Pearson's correlations were performed to determine the relationship between the time since the most recent concussion and balance performance. A Bonferonni adjusted a priori α < 0.025 was used for all analyses. RESULTS: Static and dynamic balance performance did not significantly differ between groups. No significant correlation was found between the time since the most recent concussion and balance performance. CONCLUSIONS: Collegiate athletes with a history of concussion do not present with static or dynamic balance deficits when measured using clinical assessments. More research is needed to determine whether the Y Balance Test-Lower Quarter is sensitive to acute balance deficits following concussion.

Hip, Knee, and Ankle Osteoarthritis Negatively Affects Mechanical Energy Exchange.

BACKGROUND: Individuals with osteoarthritis (OA) of the lower limb find normal locomotion tiring compared with individuals without OA, possibly because OA of any lower limb joint changes limb mechanics and may disrupt transfer of potential and kinetic energy of the center of mass during walking, resulting in increased locomotor costs. Although recovery has been explored in asymptomatic individuals and in some patient populations, the effect of changes in these gait parameters on center of mass movements and mechanical work in patients with OA in specific joints has not been well examined. The results can be used to inform clinical interventions and rehabilitation that focus on improving energy recovery. QUESTIONS/PURPOSES: We hypothesized that (1) individuals with end-stage lower extremity OA would exhibit a decrease in walking velocity compared with asymptomatic individuals and that the joint affected with OA would differntially influence walking velocity, (2) individuals with end-stage lower extremity OA would show decreased energy recovery compared with asymptomatic individuals and that individuals with end-stage hip and ankle OA would have greater reductions in recovery than would individuals with end-stage knee OA owing to restrictions in hip and ankle motion, and (3) that differences in the amplitude and congruity of the center of mass would explain the differences in energy recovery that are observed in each population. METHODS: Ground reaction forces at a range of self-selected walking speeds were collected from individuals with end-stage radiographic hip OA (n = 27; 14 males, 13 females; average age, 55.6 years; range, 41-70 years), knee OA (n = 20; seven males, 13 females; average age, 61.7 years; range, 49-74 years), ankle OA (n = 30; 14 males, 16 females; average age, 57 years; range, 45-70 years), and asymptomatic individuals (n = 13; eight males, five females; average age, 49.8 years; range, 41-67 years). Participants were all patients with end-stage OA who were scheduled to have joint replacement surgery within 4 weeks of testing. All patients were identified by the orthopaedic surgeon as having end-stage radiographic disease and to be a candidate for joint replacement surgery. Patients were excluded if they had pain at any other lower extremity joint, previous joint replacement surgery, or needed to use an assistive device for ambulation. Patients were enrolled if they met the study inclusion criteria. Our study was comparative and cohorts could be compared with each other, however, the asymptomatic group served to verify our methods and provided a recovery standard with which we could compare our patients. Potential and kinetic energy relationships (% congruity) and energy exchange (% recovery) were calculated. Linear regressions were used to examine the effect of congruity and amplitude of energy fluctuations and walking velocity on % recovery. Analysis of covariance was used to compare energy recovery between groups. RESULTS: The results of this study support our hypothesis that individuals with OA walk at a slower velocity than asymptomatic individuals (1.4 ± 0.2 m/second, 1.2-1.5 m/second) and that the joint affected by OA also affects walking velocity (p < 0.0001). The cohort with ankle OA (0.9 ± 0.2 m/second, 0.77-0.94 m/second) walked at a slower speed relative to the cohort with hip OA (1.1 ± 0.2 m/second, 0.96-1.1 m/second; p = 0.002). However, when comparing the cohorts with ankle and knee OA (0.9 ± 0.2 m/second, 0.77-0.94 m/second) there was no difference in walking speed (p = 0.16) and the same was true when comparing the cohorts with knee and hip OA (p = 0.14). Differences in energy recovery existed when comparing the OA cohorts with the asymptomatic cohort and when examining differences between the OA cohorts. After adjusting for walking speeds these results showed that asymptomatic individuals (65% ± 3%, 63%-67%) had greater recovery than individuals with hip OA (54% ± 10%, 50%-58%; p = 0.014) and ankle OA (47% ± 13%, 40%-52%; p = 0.002) but were not different compared with individuals with knee OA (57% ± 10%, 53%-62%; p = 0.762). When speed was accounted for, 80% of the variation in recovery not attributable to speed was explained by congruity with only 10% being explained by amplitude. CONCLUSIONS: OA in the hip, knee, or ankle reduces effective exchange of potential and kinetic energy, potentially increasing the muscular work required to control movements of the center of mass. CLINICAL RELEVANCE: The fatigue and limited physical activity reported in patients with lower extremity OA could be associated with increased mechanical work of the center of mass. Focused gait retraining potentially could improve walking mechanics and decrease fatigue in these patients.

Lower Extremity Movement Differences Persist After Anterior Cruciate Ligament Reconstruction and When Returning to Sports.

OBJECTIVE: To examine how landing mechanics change in patients after anterior cruciate ligament reconstruction (ACL-R) between 6 months and 12 months after surgery. DESIGN: Case-series. SETTING: Laboratory. PARTICIPANTS: Fifteen adolescent patients after ACL-R participated. INTERVENTIONS: Lower extremity three-dimensional motion analysis was conducted during a bilateral stop jump task in patients at 6 and 12 months after ACL-R. Joint kinematic and kinetic data, in addition to ground reaction forces, were collected at each time point. MAIN OUTCOME MEASURES: During the stop jump landing, the peak joint moments and the initial and peak joint motion at the ankle, knee, and hip were examined. The peak vertical ground reaction force was also examined. RESULTS: Interactions were observed for both the peak knee (P = 0.03) and hip extension moment (P = 0.07). However, only the hip extension moment was symmetrical level at 12 months. Statistically significant (P < 0.05) side-to-side differences existed for the ankle angle at initial contact, peak plantarflexion moment, peak hip flexion angle, and peak impact vertical ground reaction force independent of time. CONCLUSIONS: The findings of this study suggest that sagittal plane moments at the knee and hip demonstrate an increase in symmetry between 6 months and 1 year after ACL-R surgery, however, symmetry of the knee extension moment is not established by 12 months after surgery. The lack of change in the variables across time was unexpected. As a result, it is inappropriate to expect a change in landing mechanics solely as a result of time alone after discharge from rehabilitation.

Gender Differences in Plantar Loading During an Unanticipated Side Cut on FieldTurf.

OBJECTIVE: To determine whether force-time integral (FTI) and maximum force (MF) are significantly different between genders when performing an unanticipated side cut on FieldTurf. DESIGN: Thirty-two collegiate athletes (16 men and 16 women) completed 12 unanticipated cutting trials, while plantar pressure data were recorded using Pedar-X insoles. SETTING: Controlled Laboratory Study. PARTICIPANTS: Division I cleated sport athletes with no previous foot and ankle surgery, no history of lower extremity injury in the past 6 months, and no history of metatarsal stress fracture. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Maximum force and the FTI in the total foot, medial midfoot (MMF), lateral midfoot (LMF), medial forefoot (MFF), middle forefoot (MiddFF), and the lateral forefoot (LFF). RESULTS: Males had a greater FTI beneath the entire foot (TF) (P < 0.001). Females had a significantly higher MF beneath the LMF (P = 0.001), MiddFF (P < 0.001), and LFF (P = 0.001). Males had a significantly greater MF beneath the MMF (P = 0.003) and greater FTI beneath the MMF (P < 0.001) and MFF (P = 0.002). CONCLUSIONS: Significant differences in plantar loading exist between genders with males demonstrating increased loading beneath the TF in comparison with females. Females had overall greater loading on the lateral column, whereas males had greater loading on the medial column of the foot. CLINICAL RELEVANCE: The results of this study indicate that plantar loading is different between genders; therefore, altering cleated footwear to be gender specific may result in more optimal foot loading patterns. Optimizing cleated shoe design could decrease the risk for metatarsal stress fractures.

Functional Movement Competency and Dynamic Balance After Anterior Cruciate Ligament Reconstruction in Adolescent Patients.

BACKGROUND: Adolescent patients undergoing anterior cruciate ligament (ACL) reconstruction may not adequately recover safe movement patterns before returning to sport participation. The aims of this study were to assess functional movement and dynamic balance 9 months after primary ACL reconstruction in adolescent patients, and to assess for any maturity-specific differences that may guide rehabilitation strategies. METHODS: A series of 39 adolescent patients who underwent primary, anatomic, transphyseal ACL reconstruction using hamstrings autograft from October 2009 to January 2013 were identified from a research database: 17 skeletally immature (SI) patients (mean age 13.6±1.6 y) and 22 skeletally mature (SM) patients (mean age 16.6±1.2 y). An adult reference population of 16 primary ACL reconstruction patients (mean age 27.4±4.0 y) was also identified. All patients followed a standardized operative and rehabilitation protocol. The 3 patient groups were compared 9 months postoperatively using the Functional Movement Screen (FMS) to assess movement competency and the Lower Quarter Y-Balance Test (LQYBT) to assess single-limb dynamic balance. RESULTS: Nine months postoperatively, the FMS scores for all 3 groups indicated an increased risk for lower extremity injury (total score ≤14). With respect to specific movement patterns, the SI group displayed inferior active straight leg raise score (P=0.006) despite a lower incidence of pain with this movement. With the LQYBT, there was no significant difference in mean anterior (P=0.987), posterolateral (P=0.349), or posteromedial (P=0.870) reach asymmetry between the 3 groups; however, the adolescent groups demonstrated wider ranges of anterior reach asymmetry than the adult group indicating an increased risk for injury. CONCLUSIONS: Adolescent patients undergoing primary ACL reconstruction do not consistently recover adequate functional movement patterns by 9 months postoperatively to permit a safe return to sport. We have identified unique functional movement deficits in SI and SM adolescents, which highlight the need for maturity-specific rehabilitation strategies for adolescent patients undergoing ACL reconstruction. LEVEL OF EVIDENCE: Level IV­retrospective cohort

Are Range of Motion Measurements Needed When Calculating the Harris Hip Score?

BACKGROUND: Often the patient-reported outcome (PRO) component of the Harris Hip Score (HHS) is completed, but the physician-assessed range of motion (ROM) component is not. The PRO component only is called a modified Harris Hip Score (mHHS). The purpose of this study was to determine if a statistically significant or clinically meaningful difference existed when calculating the HHS with and without the physician-reported ROM portion. METHODS: Included patients had complete HHS data (both physician and PRO components). Surgical procedure (primary or revision) was recorded for each subject. American Society of Anesthesiologists score was divided into low and high groups. Body mass index was divided into 4 categories. The study used a repeated measures design. RESULTS: Data on 483 patients were collected between 12 and 60 months postoperatively (mean follow-up: 32.5 months, mean age: 55.9 ± 13.5 years). A mean difference of 4 points existed between the 2 groups: HHS group average score was 84.56 ± 13.18, and mHHS group average score was 88.74 ± 13.77. American Society of Anesthesiologists score, body mass index, and surgical type demonstrated a significant interaction with the HHS calculation method (P < .001). Primary total joint patients demonstrated a greater difference between the 2 scoring methods compared with revision patients. CONCLUSION: No clinically meaningful difference in outcomes was found between the mHHS and the HHS. The calculation of the HHS is dependent on the inclusion of the ROM measurement. However, the small point difference between the HHS and mHHS indicates that the mHHS is still useful as an accurate determinant of patient clinical outcome, and ROM assessment is not essential.

Unipedal balance is affected by lower extremity joint arthroplasty procedure 1 year following surgery.

Lower Extremity Joint Arthroplasty (LEJA) surgery is an effective way to alleviate painful osteoarthritis. Unfortunately, these surgeries do not normalize the loading asymmetry during the single leg stance phase of gait. Therefore, we examined single leg balance in 234 TJA patients (75 hips, 65 knees, 94 ankles) approximately 12 months following surgery. Patients passed if they maintained single leg balance for 10s with their eyes open. Patients one year following total hip arthroplasty (THA-63%) and total knee arthroplasty (TKA-69%) had similar pass rates compared to a total ankle arthroplasty (TAA-9%). Patients following THA and TKA exhibit better unilateral balance in comparison with TAA patients. It may be beneficial to include a rigorous proprioception and balance training program in TAA patients to optimize functional outcomes.

A single set of biomechanical variables cannot predict jump performance across various jumping tasks.

Vertical jump performance is related to high-level function in athletics. The purpose of this study was to determine whether a single set of biomechanical variables exist that can predict vertical jump height during multiple jumping strategies: single foot jump, drop jump, and countermovement jump. Three-dimensional mechanics were collected during the 3 different jumping tasks in 50 recreational male athletes. Three successful trials were analyzed for each jump type. Testing order was randomized to minimize fatigue effects, and the dominant limb was used for analysis. All discrete variables were correlated to jump height and the 10 variables that had the strongest correlation were inserted into a linear regression model to identify what variables predicted maximum jump height. No single set of variables that predicted jump height existed across all 3 jumping tasks. One foot jump height was predicted by peak knee power, peak hip extension moment, peak knee extension velocity, and the percentage of the trial when peak knee flexion velocity occurred (r = 0.58). Countermovement jump height was predicted by peak hip power, ankle range of motion, and knee range of motion (r = 0.65). Drop jump height was predicted by the peak vertical ground reaction force and the percentage of the trial when the peak hip velocity occurred (r = 0.37). A single set of variables was not identified that could predict jump performance across different types of jumping tasks; therefore, additional interventional investigations are needed to better understand how to alter and improve jump performance.

Use of Liposomal Bupivacaine Instead of an Epidural Can Improve Outcomes Following Total Knee Arthroplasty.

The purpose of this study was to compare periarticular injection of liposomal bupivacaine (LB) to epidural analgesia as part of multimodal pain management strategy for total knee arthroplasty (TKA). A retrospective review of 50 patients undergoing TKA compared 25 patients who received LB to 25 patients who received an epidural. After postoperative day 1, patients who received LB exhibited significantly lower (p < .001) pain scores than those who received an epidural. Patients who received LB also had a significantly shorter length of hospital stay (p < .0001), greater range of motion on postoperative day 1, and walked significantly farther (p < .001) on postoperative day 1. LB appears to provide effective pain control leading to shorter hospital stays and improved early physical function compared with standard pain management with an epidural.

Percent body fat more associated with perioperative risks after total joint arthroplasty than body mass index.

Understanding the impact of obesity on elective total joint arthroplasty (TJA) remains critical. Perioperative outcomes were reviewed in 316 patients undergoing primary TJA. Higher percent body fat (PBF) was associated with postoperative blood transfusion, increased hospital length of stay (LOS) >3 days, and discharge to an extended care facility while no significant differences existed for BMI. Additionally, PBF of 43.5 was associated with a 2.4× greater likelihood of blood transfusion, PBF of 36.5 with a 1.9× greater likelihood for LOS >3 days, and PBF of 36.0 with a 1.4× greater likelihood for discharge to an extended care facility. PBF may be a more effective measure than BMI to use in screening for perioperative risks and acute outcomes associated with obese total joint patients.

Characterizing upper extremity kinematics in typically developing children during box and blocks test.

Upper extremity kinematics are important for understanding functional ability and performance improvements. The Box and Blocks test (BBT) is a standardized functional test used to measure manual dexterity when evaluating children or patients following a stroke. The BBT measures the number of blocks moved in one minute and therefore, kinematic measures and compensatory strategies cannot be assessed. This study examined the correlation between upper extremity kinematics and cycle time per block movement during the BBT in three age groups (7-, 9-, and 11-year-olds). Participants completed one BBT session while test scores and kinematic measures (hand velocity and position and shoulder, elbow, and wrist range of motion and peak joint angles) were captured using standard three-dimensional motion capture techniques. Kinematic measures were determined for block movements during the middle of each BBT trial. A mixed-effects model was used to identify group differences (α = 0.05). BBT score was different (p = 0.005) between the 7- (44.88 ± 6.03) and the 11-year-old age group (56.95 ± 8.37) along with peak shoulder flexion (p = 0.024) and abduction (p = 0.022). Peak elbow flexion was different (p = 0.049) between the 9- and 11-year-old age groups. No differences were seen between the 7- and 9-year-old age groups. Pearson's Correlation Coefficients were determined between cycle time and each significant kinematic measure, where the cycle time is specific to each block movement (BBT score) and is correlated to the BBT score. This resulted in weak correlations for all the comparisons. Therefore, using BBT score alone is not representative of UE kinematics and both should be collected during this task to provide insight into movement mechanics in a pediatric population.

The effect of total ankle arthroplasty on mechanical energy exchange.

Total ankle arthroplasty (TAA) is a common surgical solution for patients with debilitating arthritis of the ankle. Prior to surgery patients experience high levels of pain and fatigue and low mechanical energy recovery. It is not known if TAA restores healthy levels of mechanical energy recovery in this patient population. This study was designed to determine whether mechanical energy recovery was restored following TAA. Ground reaction forces during self-selected speed walking were collected from patients with symptomatic, unilateral ankle arthritis (N = 29) before and one and two years after primary, unilateral TAA. The exchange of potential (PE) and kinetic (KE) energy was examined, and direction of change (%congruity) and energy exchange (%recovery) between the two curves was calculated, with those subjects with low congruity experiencing high energy recovery. Linear regressions were used to examine the impact of walking speed, congruity, and amplitude of the center of mass (COM) displacement on %recovery, while ANOVA and ANCOVA models were used to compare energy recovery and congruity across the three time points. Gender, BMI, and age at surgery had no effect in this study. TAA improved walking speed (p = 0.001), increased energy recovery (p = 0.020), and decreased congruity (p = 0.002), and these levels were maintained over at least two years. Differences in congruity were independent of walking speed. In some patients, especially those who are severely debilitated by ankle arthritis, TAA is effective in restoring mechanical energy recovery to levels similar to an asymptomatic population of a similar age recorded by other studies.

End-stage ankle arthritis alters dynamic stability during gait as measured by margin of stability between limbs and compared to healthy controls.

OBJECTIVE: This study aimed to assess dynamic stability in individuals with end-stage ankle arthritis compared to healthy controls by evaluating the margin of stability (MoS) during gait. DESIGN: A cohort of 50 participants with end-stage ankle arthritis (AA) and 50 matched healthy controls (HC) were analyzed from an IRB approved database. Kinematic data were collected using an eight-camera motion analysis system, and MoS was calculated based on the extrapolated center of mass (XCoM) and the base of support (BoS). Statistical analysis was performed using a linear mixed effects model with gait speed as a covariate. RESULTS: The analysis revealed a significant interaction between the group (AA vs. HC) and limb (arthritic vs. non-arthritic) at heel-strike and midstance. The non-arthritic limb demonstrated a significantly smaller AP MoS during heel-strike compared to the arthritic limb and either of the limbs of the HC group (p < 0.001). The arthritic limb demonstrated a significantly greater ML MoS during midstance compared to the non-arthritic limb and either of the limbs of the HC group (p < 0.001). AA group had significant slower gait speed (p < 0.001), smaller step length (p = 0.015) and smaller locomotor rehabilitation index (p < 0.001) than HC. CONCLUSION: Individuals with end-stage ankle arthritis exhibit altered dynamic stability during gait, with a significantly smaller AP MoS on the non-arthritic limb at heel-strike and greater ML MoS on the arthritic limb at midstance compared to healthy controls. Our results suggest that individuals with ankle arthritis are less stable when navigating single limb support of the arthritic limb. Further research should further examine the associations with fall risk in patients with ankle arthritis and evaluate the effectiveness of therapeutic interventions targeting these factors.