Is a Three-component Video-based Version of the Foot Posture Index Valid for Assessing Pediatric Patients With Orthopaedic and Neurologic Foot Conditions?

BACKGROUND: The Foot Posture Index-6 (FPI6) is an assessment of foot position that can be useful for patients with orthopaedic complaints. The FPI6 rates six components of foot position from -2 to +2, resulting in a total score on a continuum between -12 (severe cavus or supination) to +12 (severe planus or pronation). The subscores are ratings made by the examiner and are subjective assessments of deformity severity. The FPI6 requires palpation of bony structures around the foot and therefore must be administered live during physical examination. Because it is sometimes impractical to perform these assessments live, such as for retrospective research, a valid and reliable video-based tool would be very useful. QUESTIONS/PURPOSES: This study examines a version of the FPI using three of the original six components to determine: (1) Are scores from the three-component version of the FPI (FPI3) associated with those from the original six-component version (FPI6)? (2) Is the three-component FPI3 as reliable as the original six-component FPI6? (3) Are FPI3 assessments done retrospectively from video as reliable as those done live? METHODS: A retrospective group of 155 participants (106 males; mean age 13 ± 4 years) was studied. All had undergone gait analysis including videotaping and in-person assessment using the FPI6. Ratings for three components (calcaneus inversion/eversion, medial arch congruence, and forefoot abduction/adduction) were extracted yielding an FPI3 score ranging from -6 to +6. The other three components of the FPI6 (talar head palpation, curves above and below the lateral malleolus, talonavicular joint bulge) were excluded from the FPI3. FPI6 and FPI3 scores and side-to-side asymmetry were compared for all participants and for diagnosis subgroups (cerebral palsy and Charcot-Marie-Tooth disease) using a Pearson correlation. Agreement for foot posture categorization between the FPI6 and FPI3 was assessed using weighted kappa. Intra- and interrater reliability of live and video-based assessments for the FPI3 and its components were examined using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. RESULTS: Scores from the FPI3 and FPI6 are highly associated with each other, suggesting the FPI3 is an adequate substitute for the FPI6. FPI6 and FPI3 scores (r = 0.98) and asymmetry (r = 0.96) were highly correlated overall and within the cerebral palsy (r = 0.98 for scores; r = 0.98 for asymmetry) and Charcot-Marie-Tooth (r = 0.96 for scores; r = 0.90 for asymmetry) subgroups (all p < 0.001). Agreement between the FPI6 and FPI3 was high for foot posture categorization (weighted agreement = 95%, weighted κ = 0.88; p < 0.001). Interrater reliability for live ratings was similar for FPI3 and FPI6 and high for both measures (ICC = 0.95 for FPI6 and 0.94 for FPI3; both p < 0.001). High reliability was seen in video versus live ratings for the FPI3 total score and each of its components regardless of whether they were performed by the same (ICC = 0.98) or different (ICC = 0.97) raters (both p < 0.001), and interrater reliability remained high when the FPI3 was scored from video recordings (ICC = 0.96; p < 0.001). CONCLUSION: The FPI3 is valid and reliable when done live or from video or by the same or different examiners. It is suitable for retrospective and multicenter research studies, provided videos are done using standardized protocols. Further research is recommended investigating possible ceiling and floor effects in patients with pathologic conditions.Level of Evidence Level III, diagnostic study.

Changes in walking velocity and stride parameters with age in children with Charcot-Marie-Tooth disease.

The purpose of this study is to assess how Charcot-Marie-Tooth disease, a group of inherited peripheral neuropathies that result in distal weakness, affects walking velocity over time in comparison to age-matched controls. Comprehensive gait analysis of 57 children (mean age 12.0, SD 3.7 years) compared to 76 age-matched controls (mean age 10.1, SD 3.4 years) demonstrated slower walking velocity (p<0.001) due to both shorter stride length (p<0.001) and diminished cadence (p=0.01). There was higher walking velocity (p<0.001), stride length (p=0.002) and cadence (p<0.001) in patients with dorsiflexor strength ≥3 and higher walking velocity (p=0.001) and cadence (p=0.03) in patients plantar flexor strength ≥4. Analysis of Charcot-Marie-Tooth type 1 and type 2 subgroups showed that walking velocity increased significantly with age in controls (p=0.001) but did not increase in children with either subtype (p>0.54). Stride length increased significantly with age in all groups (p<0.001) but at a slower rate in type 1 and 2 compared to controls. These differences contributed to increasing deficits in walking velocity and stride length with age in type 1 and 2 in comparison to controls, with deficits appearing earlier in type 2. Since the slower walking velocity in children with Charcot-Marie-Tooth disease is primarily due to short stride length, treatments that enable improved stride length, such as plantar flexor strengthening and bracing, may improve walking velocity and associated gait function.

Lower extremity characteristics in recurrent clubfoot: Clinical and gait analysis findings that may influence decisions for additional surgery.

BACKGROUND: Patients with recurrent clubfoot may seek intervention to address impairments that impact gait function. An understanding of these impairments and associated gait issues will provide valuable information about ongoing treatment requirements. RESEARCH QUESTION: The purpose of this study was to describe the prevalence of impairments and associated gait deviations in children with recurrent clubfoot and to evaluate whether these findings differ depending on unilateral or bilateral presentation. METHODS: Eighty-four affected feet (42 unilateral, 21 bilateral) were retrospectively reviewed. History, clinical exam, and gait data were collected. Statistical analysis included evaluations of associations between clinical exam and gait parameters and differences among patients with unilateral versus bilateral clubfoot and a database of healthy controls. RESULTS: The average age was 7.5 ±â€¯3.3 years for unilateral and 7.0 ±â€¯2.8 years for bilateral patients. Patients presented with limited passive ankle dorsiflexion (unilateral/bilateral:67%/57%), limited ankle plantar flexion strength (unilateral/bilateral:53%/55%), metatarsus adductus (unilateral/bilateral:86%/83%) and internal foot-thigh angles (unilateral/bilateral:83%/82%), while only a subset presented with internal bi-malleolar axis angles (unilateral/bilateral:36%/45%). The most common gait deviations were internal foot progression (unilateral/bilateral:76%/73%), external hip rotation (unilateral/bilateral:66%/69%), reduced peak ankle plantar flexion moments (unilateral/bilateral:84%/83%), and reduced peak ankle power generation (unilateral/bilateral:67%/74%). Passive dorsiflexion was significantly correlated with peak dorsiflexion during stance and swing in both groups. Patients with unilateral compared to bilateral clubfoot showed decreased peak dorsiflexion and an associated knee flexor moment. SIGNIFICANCE: Patients with recurrent clubfoot show gait deviations at the ankle that can be explained by joint level impairment and compensations at the knee, hip and pelvis. Patients with unilateral clubfoot typically show decreased dorsiflexion range of motion and associated greater gait impacts and compensations than bilateral clubfoot. Understanding the relationships between impairments and gait function and the implications of unilateral versus bilateral clubfoot will help improve prognostic ability and optimize future treatment outcomes.

Mini-C-arm fluoroscopy for emergency-department reduction of pediatric forearm fractures.

BACKGROUND: Reduction of pediatric forearm fractures with the patient under sedation in the emergency department is a common practice throughout the United States. We hypothesized that the use of a mini-c-arm fluoroscopy device as an alternative to routine radiographs for evaluation of fracture reduction would (1) allow a more anatomic fracture reduction, (2) decrease the number of repeat reductions or subsequent procedures, (3) reduce overall radiation exposure to the patient, and (4) decrease the orthopaedic consultation time in the emergency department. METHODS: A retrospective cohort analysis of 279 displaced forearm and wrist fractures treated with closed reduction and casting with the patient under sedation in the emergency department of a level-I pediatric trauma center was performed, and the data were compared with historical controls. One hundred and thirteen fracture reductions were assessed with a mini-c-arm device, and 166 fracture reductions were evaluated with radiographs. All patients had radiographs of the injury. Blinded, independent reviewers graded the quality of reduction for residual angulation and translation of the reduced fracture. Radiation exposure was determined by the average number of radiographs made through either modality. Emergency department and outpatient charts were reviewed to determine the total orthopaedic consultation time and the need for repeat reductions or operative intervention. RESULTS: Pediatric forearm fractures undergoing closed reduction with assistance of the mini c-arm had a significant improvement in reduction quality (average angulation [and standard deviation], 6° ± 4° vs. 8 ± 6°; p = 0.02), a decrease in repeat fracture reduction and need for subsequent operative treatment (two [2%] of 113 fractures vs. fourteen [8.4%] of 166 fractures; p = 0.0001), and a decrease in radiation exposure to the patient (mean, 14.0 ± 10.3 mrem vs. 50.0 ± 12.7 mrem). The average orthopaedic consultation time was decreased with use of a mini c-arm (28 ± 12 min vs. 47 ± 19 min, p < 0.001). CONCLUSIONS: Use of the mini c-arm to assist in the closed reduction of pediatric forearm and wrist fractures in the emergency department can improve the quality of the reduction, decrease the radiation exposure to the patient, and decrease the need for repeat fracture reduction or additional procedures. Mini-c-arm imaging can also decrease the average orthopaedic consultation time for fracture reduction.