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.

Does Size Really Matter? Incidence of Periprosthetic Fractures After Femoral Osteotomy in Patients With Cerebral Palsy.

OBJECTIVE: Of children, 30% to 35% with cerebral palsy (CP) develop hip subluxation or dislocation and often require reconstructive hip surgery, including varus derotation osteotomy (VDRO). A recent literature review identified postoperative fractures as the most common complication (9.4%) of VDROs. This study aimed to assess risk factors for periprosthetic fracture after VDRO in children with CP. METHODS: A total of 347 patients (644 hips, 526 bilateral hips) with CP and hip subluxation or dislocation (129 females; mean age at index VDRO: 8.6 y, SD 3.4, range: 1.5 to 17.7; 2 Gross Motor Function Classification System (GMFCS) I, 35 GMFCS II, 39 GMFCS III, 119 GMFCS IV, 133 GMFCS V, 21 unavailable) were included in this retrospective, single-group intervention (VDRO) study at a tertiary referral center. Imaging and clinical documentation for patients age 18 years or younger at index surgery, treated with VDRO were reviewed to determine demographic data, GMFCS level, surgeon, type of hardware implanted, use of anticonvulsants and steroids, type of postoperative immobilization, presence of periprosthetic fractures, fracture location and mechanism, and time from surgery to fracture. Potential determinants of periprosthetic fractures were assessed using mixed effects logistic regression. RESULTS: Of 644 hips, 14 (2.2%, 95% CI: 1.3%, 3.6%) sustained a periprosthetic fracture, at a median of 2.1 years postoperatively (interquartile range: 4.6 y, range: 1.2 mo to 7.8 y). Patients with a fracture had a median age at index surgery of 7.3 years (interquartile range: 4.3, range: 2.8 to 17.8; 1 GMFCS II, 6 GMFCS IV, 7 GMFCS V). Periprosthetic fractures were not significantly related to age at index surgery ( P = 0.18), sex ( P = 0.30), body mass index percentile ( P = 0.87), surgery side ( P = 0.16), anticonvulsant use ( P = 0.35), type of postoperative immobilization ( P = 0.40), GMFCS level ( P = 0.31), or blade plate size ( P = 0.17). Only surgeon volume significantly related to periprosthetic fracture (odds ratio = 5.03, 95% CI: 1.53, 16.56, P = 0.008), with the highest-volume surgeon also using smaller blade plates ( P < 0.01). CONCLUSIONS: Periprosthetic fractures after VDRO surgery in children with CP are uncommon, and routine hardware removal appears unnecessary. The data suggest that the common dogma of putting in the largest blade plate possible to maximize fixation may increase the risk of periprosthetic fracture. Due to the overall low fracture rate, especially when contextualized relative to the risk of hardware removal, a reactive approach to hardware removal appears warranted. LEVEL OF EVIDENCE: Level III-retrospective study (targeting varus derotational osteotomies in children with cerebral palsy).

Update on the reliability of gait analysis interpretation in cerebral palsy: Inter-institution agreement.

BACKGROUND: Studies have shown good reliability for gait analysis interpretation among surgeons from the same institution. However, reliability among surgeons from different institutions remains to be determined. RESEARCH QUESTION: Is gait analysis interpretation by surgeons from different institutions as reliable as it is for surgeons from the same institution? METHODS: Gait analysis data for 67 patients with cerebral palsy (CP) were reviewed prospectively by two orthopedic surgeons from different institutions in the same state, each with > 10 years' experience interpreting gait analysis data. The surgeons identified gait problems and made treatment recommendations for each patient using a rating form. Percent agreement between raters was calculated for each problem and treatment, and compared to expected agreement based on chance using Cohen's kappa. RESULTS: For problem identification, the greatest agreement was seen for equinus (85% agreement), calcaneus (88%), in-toeing (89%), and out-toeing (90%). Agreement for the remaining problems ranged between 66-78%. Percent agreement was significantly higher than expected due to chance for all issues (p ≤ 0.01) with modest kappa values ranging from 0.12 to 0.51. Agreement between surgeons for treatment recommendations was highest for triceps surae lengthening (89% agreement), tibial derotation osteotomy (90%), and foot osteotomy (87%). Agreement for the remaining treatments ranged between 72-78%. Percent agreement for all treatments was significantly higher than the expected values (p ≤ 0.002) with modest kappa values ranging from 0.22 to 0.52. SIGNIFICANCE: Previous research established that computerized gait analysis data interpretation is reliable for surgeons within a single institution. The current study demonstrates that gait analysis interpretation can also be reliable among surgeons from different institutions. Future research should examine reliability among physicians from more institutions to confirm these results.

Anterior Distal Femoral Hemiepiphysiodesis Does Not Change Pelvic Tilt in Children With Cerebral Palsy.

BACKGROUND: Anterior distal femoral hemiepiphysiodesis (ADFH) is a surgical treatment choice to correct flexed knee gait and fixed knee flexion deformities in children with cerebral palsy who are skeletally immature. Increased anterior pelvic tilt has been reported after surgeries that correct knee flexion deformities, including hamstring lengthening (HSL) and distal femoral extension osteotomies, but anterior pelvic tilt has not been studied after ADFH. We hypothesized that anterior pelvic tilt would increase after ADFH, especially when combined with HSL, and it would correlate with the change in minimum knee flexion in stance and dynamic hamstring lengths. METHODS: Thirty-four eligible participants (age: 13.0, SD: 2.0) were included. Change in mean pelvic tilt across the gait cycle was compared as a function of clinical and gait parameters using linear mixed models. The relationship of change in pelvic tilt to change in other variables was examined using Pearson correlation. RESULTS: Overall, anterior pelvic tilt increased significantly after ADFH by 4.4 degrees ( P = 0.02). Further, the analysis revealed anterior pelvic tilt only increased significantly in the group that had concurrent HSL (11.1 degrees, P < 0.001). Overall, minimum knee flexion significantly decreased (increase in knee extension) in stance (-19.1 degrees, P < 0.001) and there was an increase in maximum normalized dynamic hamstring lengths (0.03, P < 0.001). The anterior pelvic tilt increased significantly in Gross Motor Function Classification System levels III to IV (5.9 degrees, P = 0.02) but did not change significantly in Gross Motor Function Classification System I to II (2.5 degrees, P = 0.37). Change in pelvic tilt was correlated with change in maximum dynamic hamstring lengths ( r = 0.87, P < 0.0001) and change in minimum knee flexion in stance ( r = -0.71, P < 0.0001). CONCLUSIONS: Anterior distal hemiepiphysiodesis without concurrent HSL for flexion knee deformities does not result in increased anterior pelvic tilt. Surgeons should consider anterior distal hemiepiphysiodesis in patients with cerebral palsy and flexed knee gait, who preoperatively have long dynamically modeled hamstrings, are skeletally immature, and when maintenance of pelvic tilt is desired. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Predictors of Changes in Pelvic Rotation after Surgery with or without Femoral Derotational Osteotomy in Ambulatory Children with Cerebral Palsy.

Asymmetry of pelvic rotation affects function. However, predicting the post-operative changes in pelvic rotation is difficult as the root causes are complex and likely multifactorial. This retrospective study explored potential predictors of the changes in pelvic rotation after surgery with or without femoral derotational osteotomy (FDRO) in ambulatory children with cerebral palsy (CP). The change in the mean pelvic rotation angle during the gait cycle, pre- to post-operatively, was examined based on the type of surgery (with or without FDRO) and CP distribution (unilateral or bilateral involvement). In unilaterally involved patients, pelvic rotation changed towards normal with FDRO (p = 0.04), whereas patients who did not undergo FDRO showed a significant worsening of pelvic asymmetry (p = 0.02). In bilaterally involved patients, the changes in pelvic rotation did not differ based on FDRO (p = 0.84). Pelvic rotation corrected more with a greater pre-operative asymmetry (ß = -0.21, SE = 0.10, p = 0.03). Sex, age at surgery, GMFCS level, and follow-up time did not impact the change in pelvic rotation. For children with hemiplegia, internal hip rotation might cause compensatory deviation in pelvic rotation, which could be improved with surgical correction of the hip. The predicted changes in pelvic rotation should be considered when planning surgery for children with CP.

Comparison of kinematics between Theia markerless and conventional marker-based gait analysis in clinical patients.

BACKGROUND: Markerless motion capture systems have the potential to make clinical gait analysis more efficient and convenient. Theia3D is a commercially available markerless system that may serve as an alternative to traditional gait analysis for clinical gait laboratories. RESEARCH QUESTION: What is the concurrent validity of markerless gait analysis using Theia3D compared to traditional marker-based gait analysis in pediatric clinical gait patients? METHODS: Thirty-six patients (20 male, age 2-25 years) with a range of diagnoses underwent clinical gait analysis with data being captured concurrently by a traditional marker-based motion capture system (Vicon Nexus) and a commercial markerless system (Theia3D). Multiple left strides were averaged for each subject, and the difference in kinematics (Theia - Vicon) was calculated over the gait cycle and evaluated using root mean square difference (RMSD), mean difference, and RMSD after subtracting the mean value across the gait cycle (RMSDoffset). Sub-analysis was performed for 25 patients with foot deformities, 9 wearing ankle-foot orthoses, and 6 walking with assistance (cane, crutches, walker, or handheld). RESULTS: Kinematics showed similar patterns between the marker-based and markerless systems. RMSD was < 6° except for pelvic tilt, hip flexion, ankle inversion, foot progression, and transverse plane rotation of the hip, knee, and ankle. These measures mainly differed due to an offset between the curves. After adjusting for offsets, all RMSDoffset were < 6°. RMSD was larger for patients with foot deformities, wearing orthoses, or using assistive devices, but all RMSDoffset were still < 8°. In some cases, however, the markerless system had greater trial-to-trial variability, showed a larger knee varus "bump" in swing, or failed to track the subject. SIGNIFICANCE: This study provides preliminary evidence of concurrent validity of Theia3D for pediatric patients with abnormal gait. However, some questions remain regarding identification of the knee axis and for patients with foot deformity or assistive devices.

Persistent increase in anterior pelvic tilt after hamstring lengthening in children with cerebral palsy.

BACKGROUND: Hamstring lengthening has traditionally been the surgical treatment of choice to correct flexed knee gait in children with cerebral palsy (CP). Improved passive knee extension and knee extension during gait are reported post hamstring lengthening, but concurrent increased anterior pelvic tilt also occurs. RESEARCH QUESTION: Does anterior pelvic tilt increase after hamstring lengthening in children with CP both in the short-term and mid-term, and what predicts increased post-operative anterior pelvic tilt? METHODS: 44 participants were included (age 7.2, SD 2.0 years; 5 GMFCS I, 17 GMFCS II, 21 GMFCS III, 1 GMFCS IV). Mean pelvic tilt was compared between visits, and the effect of potential predictors of change in pelvic tilt was examined using linear mixed models. The relationship of change in pelvic tilt to change in other variables was examined using Pearson correlation. RESULTS: Anterior pelvic tilt increased significantly post-operatively by 4.8° (p < 0.001). It remained significantly higher by 3.8° at 2-15 years follow-up (p < 0.001). Change in pelvic tilt was not affected by sex, age at surgery, GMFCS level, assistance during walking, time since surgery, or baseline values of hip extensor strength, knee extensor strength, knee flexor strength, popliteal angle, hip flexion contracture, step length, walking speed, maximum hip power in stance, or minimum knee flexion in stance. Pre-operative dynamic hamstring length was associated with greater anterior pelvic tilt at all visits but did not affect amount of change in pelvic tilt. Patients in GMFCS I-II showed a similar pattern of change in pelvic tilt to GMFCS III-IV. SIGNFICANCE: When considering hamstring lengthening for ambulatory children with CP, surgeons should weigh increased mid-term anterior pelvic tilt post-operatively with the desired outcome of improved knee extension in stance. Patients with neutral or posterior pelvic tilt and short dynamic hamstring lengths pre-operatively have lowest risk of excessive post-operative anterior pelvic tilt.

Gait Analysis Characteristics in Relapsed Clubfoot.

BACKGROUND: Relapse rates of clubfoot deformity after initial correction range between 19% and 68% regardless of treatment approach. Most studies focus on relapse before age 4. Little research has focused on late clubfoot relapse. The purpose of this study was to compare the gait characteristics of children with late clubfoot relapse (age ≥5 y) following treatment with the Ponseti method only compared with intra-articular and extra-articular surgeries. METHODS: A retrospective review was conducted of all patients with idiopathic clubfoot ≥5 years old who underwent computerized gait analysis for clubfoot relapse between 2001 and 2021. Joint range of motion, muscle strength, gait kinematics, and kinetics were compared among 3 groups based on prior clubfoot treatment: (1) Ponseti casting, (2) Extra-articular (EA) surgery, and (3) Intra-articular (IA) surgery. RESULTS: Sixty-eight subjects (107 feet) were included (39 bilateral). Thirty-one percent of feet had been treated with Ponseti casting alone; 57% had IA surgery, and 12% had EA surgery. The average age when presenting with late relapse was 8.2 years, 9.0 years and 10.7 years for the Ponseti, and IA and EA groups, respectively. The IA group had greater passive dorsiflexion than the other 2 groups (P<0.002), greater inversion weakness than the other 2 groups (P<0.0001), greater dorsiflexion during the stance phase of gait compared with the Ponseti group (P=0.001), and lower maximum power production at push-off compared with the other 2 groups (P=0.009). CONCLUSION: Late relapse can occur after all types of clubfoot correction. Consistent with existing literature, patients who have undergone posteromedial release surgery have significantly greater plantarflexor weakness resulting in poorer plantarflexor moment and power production during gait. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

The Effects of Prolonged Vibrotactile EMG-Based Biofeedback on Ankle Joint Range of Motion During Gait in Children with Spastic Cerebral Palsy: A Case Series.

AIMS: The objective of this case series was to examine the feasibility of vibrotactile EMG-based biofeedback (BF) as a home-based intervention tool to enhance sensory information during everyday motor activities and to explore its effectiveness to induce changes in active ankle range of motion during gait in children with spastic cerebral palsy (CP). METHODS: Ten children ages 6 to 13 years with spastic CP were recruited. Participants wore two EMG-based vibro-tactile BF devices for at least 4 hours per day for 1-month on the ankle and knee joints muscles. The device computed the amplitude of the EMG signal of the target muscle and actuated a silent vibration motor proportional to the magnitude of the EMG. RESULTS: Our results demonstrated the feasibility of the augmented sensory information of muscle activity to induce changes of the active ankle range of motion during gait for 6 children with an increase ranging from 8.9 to 51.6% compared to a one-month period without treatment. CONCLUSIONS: Preliminary findings of this case series demonstrate the feasibility of vibrotactile EMG-based BF and suggest potential effectiveness to increase active ankle range of motion, therefore serving as a promising therapeutic tool to improve gait in children with spastic CP.

Cost savings for single event multilevel surgery in comparison to sequential surgery in ambulatory children with cerebral palsy.

BACKGROUND: The purpose of this study was to determine the differences in billable provider charges between single event multilevel surgery (SEMLS) based on comprehensive gait analysis and a staged surgical approach (SSA) without comprehensive gait analysis for the orthopedic treatment of ambulatory children with cerebral palsy (CP). METHODS: The charges associated with nine common orthopedic surgical combinations (both unilateral and bilateral, soft tissue or soft tissue plus bony) for children with CP were determined and compared between SEMLS and SSA. The charges included surgical, anesthesia, operating room, recovery room, hospital stay, physical therapy, and, for SEMLS only, comprehensive computerized gait analysis. RESULTS: Total charges to complete each combination was higher for SSA than for SEMLS. The differential ranged from $10,247 to $75,069 with the percentage difference ranging from 20% to 47%. The mean difference was $43,606 (p = 0.0002). The dollar difference (r = 0.98, p < 0.0001) and percentage difference (r = 0.79, p = 0.01) were both related to the total charge of the SEMLS surgery. SIGNIFICANCE: Financial costs are lower for SEMLS vs. SSA for the treatment of multilevel gait issues in children with CP. The cost of gait analysis is much smaller than the cost differential between SEMLS and SSA. Although some patients who have SEMLS may need additional orthopedic surgery with associated costs, this is also possible for SSA. Therefore, due to the many benefits of SEMLS, which also include more informed treatment decision-making as well as reduced time away from school and work (for caregivers), SEMLS guided by gait analysis is recommended over SSA for the treatment of gait disorders in children with CP.

Variation in Functional Mobility Within Gross Motor Function Classification System Levels.

BACKGROUND AND OBJECTIVE: Variation in walking performance within Gross Motor Function Classification System (GMFCS) levels for patients with cerebral palsy (CP) is often unrecognized. The Functional Mobility Scale (FMS) rates mobility at household, school, and community distances. This study evaluated the variability of walking performance within GMFCS levels as measured by the FMS. METHODS: Retrospective review of gait analysis records for ambulatory patients with CP. FMS rating distribution at each distance was examined for GMFCS levels I-IV within age groups (below 12 or above 12 y) and compared among levels using χ2 tests. RESULTS: A total of 788 patients (499 male; age 11.2, SD 3.9 y) were included. FMS score distribution differed significantly among GMFCS levels for all distances (P<0.001). GMFCS LEVEL: I-Children walked independently on all surfaces at home and school distances at all ages. In all, 5% to 7% used wheeled mobility in the community. II-Most walked at home and school distances. Some younger children crawled at home, and 5% to 8% of all subjects used walls and furniture. Approximately 50% of subjects in both age groups used some form of walking aids or a stroller/wheelchair in the community. III-Twenty-five percent to 30% walked unaided at home, requiring walking aids or wheeled mobility at school or in the community. Forty-five percent of younger and 18% of older subjects crawled at home. Eight percent of younger and 28% of older subjects used wheelchairs at school. Seventy-three percent to 75% of all subjects used strollers/wheelchairs in the community. IV-Sixty-two percent of younger and 43% of older subjects crawled at home. Approximately 15% of all subjects did some aided walking at home. Twenty-seven percent of younger children did some aided walking at school, while only 1 older subject did so. All used strollers/wheelchairs in the community. CONCLUSION: Mobility function varies within each GMFCS level with the most variability in GMFCS II at school and community distances and GMFCS III at household distances. These findings highlight the importance of using both the GMFCS and FMS when assessing functional mobility in children with CP. LEVEL OF EVIDENCE: Level III-retrospective study.

Calcaneal Sliding Osteotomy Versus Calcaneal Lengthening Osteotomy for Valgus Foot Deformity Correction in Children With Cerebral Palsy.

BACKGROUND: Medial calcaneal sliding (CS) osteotomy and lateral column lengthening (LCL) are often performed to relieve pain and improve transverse plane alignment and gait stability for children with cerebral palsy (CP) and valgus foot deformities. The purpose of this study was to examine the effectiveness of these procedures in this population. METHODS: Retrospective medical record review (including 3D gait analysis data) of patients with CP who underwent LCL (26 subjects, 46 limbs) or CS (46 subjects, 73 limbs). Data extraction included complications (modified Clavien-Dindo system), change in standing foot position (modified Yoo system), and change in gait kinematics and kinetics preoperatively to postoperatively. Groups were compared using paired t tests, Fisher exact test, and survivorship analysis using Cox proportional hazard models. RESULTS: Subjects were 57% male, average age at surgery 11.1 (SD 2.5) years. Average length of follow-up was 3.2 (SD 2.8) years, and was longer in the LCL group (P=0.0004). Complications were minor with similar rates between groups (P=0.14). Prolonged pain and plantar hypersensitivity occurred only in the CS group. Successful maintenance of deformity correction was achieved in 52/73 limbs (71%) in the CS group and 16/44 limbs (36%) in the LCL group (P<0.001). Recurrent pes valgus and need for repeat foot surgery were more common after LCL (P=0.003 and 0.001, respectively). Recurrent pes valgus never occurred when talonavicular fusion was done concomitantly with CS. After accounting for the between group difference in length of follow-up, there was no difference in the rates of recurrent valgus or repeat foot surgery between LCL and CS. None of the variables predicted development of pes varus (P>0.20). Ankle kinematics and kinetics during gait were unchanged in both groups. CONCLUSIONS: CS and LCL have similar effectiveness in providing long-lasting correction of valgus foot deformities. Concomitant talonavicular fusion is key to success of CS for lower functioning patients with severe deformities, and obligate brace wearers. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Relationships among classifications of impairment and measures of ambulatory function for children with spina bifida.

PURPOSE: To examine associations between neurosegmental and functional level classifications in children with Spina Bifida, and determine which classification best reflects daily walking activity. MATERIALS AND METHODS: A prospective correlational study was conducted. Children with Spina Bifida were given ratings for lesion level [X-ray and International Myelodysplasia Study Group (IMSG) level determined by muscle strength] and functional level [Hoffer ambulatory level and Dias functional classification of myelomeningocele (FCM), Functional Mobility Scale (FMS)]. Daily walking activity was measured with a StepWatch monitor. Data were analyzed using Spearman rank correlation. RESULTS: Sixty-one children were included, [56% male, average age 9.8 (SD 2.7) years]. The neurosegmental level classifications, X-ray lesion level and IMSG level showed little to no correlation with each other (r = 0.17). Among functional classifications, the Dias FCM correlated strongly with the FMS (r = 0.80-0.87). Correlations with steps per day were moderate to good for the Dias FCM and the FMS (r = 0.53-0.62), fair for IMSG level (r = 0.45), and little to none for X-ray lesion level (r = 0.03). CONCLUSIONS: The Dias FCM is comprehensive, including elements of neurosegmental level and function, and correlates well with walking activity. We recommend its use for classifying function in patients with Spina Bifida.Implications for rehabilitationFunctional classifications correlate better with daily walking activity than neurosegmental level classifications for patients with Spina Bifida.The Dias FCM includes neurosegmental and functional level elements, correlates well with daily activity, and is recommended for use in classifying Spina Bifida patients.Combined use of the FMS and activity monitoring is recommended for research and clinical assessment.

Quantitative Computed Tomography Assessment of Bone Deficits in Ambulatory Children and Adolescents with Spina Bifida: Importance of Puberty.

Pathologic fractures of the femur and tibia are common in youth with spina bifida (SB). These fractures may be associated with deficient bone accrual due to decreased ambulation and skeletal loading. This prospective cohort study used quantitative computed tomography (QCT) to assess three-dimensional (3D) bone properties in children and adolescents with SB. Eighty-three ambulatory youth with SB underwent QCT imaging of the tibia at up to four annual visits between ages 6 to 16 years (294 total visits averaging 3.5 visits/patient). A total of 177 controls without disability and 10 non-ambulatory youth with SB underwent imaging once. Bone geometric properties (cortical bone area, cross-sectional area, cortical thickness, cortical density, and moments of inertia) were measured at the mid-diaphysis (50% of bone length); cross-sectional area, cancellous density, and density-weighted area were measured in the proximal (13% of bone length) and distal (90% of bone length) metaphyses. Bone properties were compared between the ambulatory SB and control participants, among SB neurosegmental subgroups (sacral, low lumbar, mid lumbar and above) as a function of pubertal stage (prepubertal, pubertal, postpubertal), and considering SB type (myelomeningocele, lipomyelomeningocele) using linear mixed effects models adjusted for sex, age, height percentile, and body mass index (BMI) percentile. Only cancellous density of both metaphyses and weighted area of the proximal metaphysis differed between ambulatory children with SB and controls before puberty. However, significant deficits in all bone properties manifested during and after puberty as moderate bone growth in the SB group failed to keep pace with the large increases normally observed during puberty. The bone deficits primarily affected patients with myelomeningocele, and similar deficits were observed at all neurosegmental levels except that cancellous density was closer to normal in the sacral group. Descriptive analysis of the 10 non-ambulatory youth with SB showed greater bone deficits than ambulatory children, particularly for cancellous density in the distal metaphysis. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Anterior distal femoral hemiepiphysiodesis with and without patellar tendon shortening for fixed knee flexion contractures in children with cerebral palsy.

PURPOSE: Surgery is often required for fixed knee flexion contractures in patients with neuromuscular conditions. Anterior distal femoral hemiepiphysiodesis (ADFH) is an alternative to distal femoral extension osteotomy (DFEO) in skeletally immature patients. ADFH is typically not accompanied by patellar tendon shortening surgery (PTS). Our purpose was to compare ADFH alone versus ADFH with PTS for treatment of fixed knee flexion contractures and crouched gait in children with cerebral palsy (CP). METHODS: Retrospective review of pre- and postoperative gait analysis data for children with CP who underwent ADFH alone, or ADFH with PTS. Data were analysed using linear mixed models to control for covariates. RESULTS: In total, 25 participants (42 limbs) were included, 17 male and eight female, mean age at surgery 12.9 (sd 1.9) years. Both groups experienced significant improvement in popliteal angle, knee extension range of motion (ROM) and knee extension in stance phase. Greater improvement was seen for all variables in the ADFH/PTS group, mainly due to greater popliteal angle and knee flexion during gait preoperatively in that group (p ≤ 0.02) rather than the procedure performed (p ≥ 0.19). There was no difference between groups postoperatively. Rate of contracture resolution was 0.5° to 1.0° per month, faster in larger contractures (p = 0.02). CONCLUSIONS: ADFH with and without PTS is effective in improving knee extension in skeletally immature patients with CP, correcting contractures at a rate of 0.5° to 1.0° per month. Combined ADFH and PTS surgery may be preferable in patients with larger contractures of up to 30° to 35°. LEVEL OF EVIDENCE: III.

Hip Dysplasia Is Not More Common in W-Sitters.

Parents are frequently cautioned by therapists, teachers, physicians, and online resources about potential negative effects of w-sitting in children (including hip dysplasia), despite lack of evidence. To examine relationships between w-sitting and hip dysplasia, a prospective cohort study was conducted of 104 patients (196 hips), aged 9.9 (standard deviation = 5.7) years, who underwent hip/pelvis radiography at a pediatric tertiary care center. Measures of hip dysplasia were taken from radiographs. Parents/patients completed a questionnaire regarding the patients' sitting habits. Associations between hip dysplasia and w-sitting were analyzed statistically. About 48/104 parents/patients (46%) reported current or past w-sitting: 11/104 (11%) current, preferred position; 23/104 (22%) current, nonpreferred position, 14/104 (13%) w-sat in past, and 56/104 (54%) never w-sat. There was no difference in measures of hip dysplasia (P > .12) or hip dysplasia frequency between w-sitters (9%) and non-w-sitters (10%; P = .81), or among w-sitting persistence groups (P = .26). W-sitting in children is not associated with hip dysplasia.

Clinical efficacy of instrumented gait analysis: Systematic review 2020 update.

BACKGROUND: This paper updates our 2011 systematic review on the clinical efficacy of three-dimensional instrumented gait analysis (3DGA). RESEARCH QUESTION: What is the current evidence base pertaining to the clinical efficacy of 3DGA? METHODS: We identified English language articles published from September 2009 to October 2019 reporting primary research that used typical motion analysis laboratory methods to study human walking. Five gait laboratory experts classified articles according to the highest type of efficacy they addressed: type 1 (technical), 2 (diagnostic accuracy), 2b (outcome prediction), 3-4 (diagnostic thinking and treatment), 5 (patient outcome), 6 (societal). Articles classified into type 3-4 and higher were rated for quality using LEGEND. RESULTS: Of 2712 articles related to the efficacy of 3DGA, over 99% addressed technical (n = 313), diagnostic (n = 1466), or outcome prediction (n = 927) efficacy. Six type 3-4 studies showed that 3DGA changes treatment plans, increases clinicians' confidence in their treatment decisions, and increases agreement among clinicians. Two type 5 articles based on a randomized controlled trial demonstrated that patient outcomes improved only when 3DGA data were available and its recommendations were followed. A population-based type 5 study found that the incidence of severe crouch gait dropped from 25% to 4% following practice changes including the addition of 3DGA. The strength of evidence was mainly 3b (lesser quality prospective cohort studies) but also included stronger studies (three level 2 controlled clinical trials). SIGNIFICANCE: Literature related to the clinical efficacy of 3DGA has grown substantially over the last decade. Thousands of articles contribute to continued improvement of data collection and interpretation, as well as understanding of gait pathology and treatment. A smaller number of studies clearly demonstrate the efficacy of 3DGA in changing and reinforcing treatment decisions, increasing clinicians' confidence in treatment planning, and increasing agreement among clinicians, as well as the potential to improve patient outcomes.

Comparison of plate and screw constructs versus screws only for anterior distal femoral hemiepiphysiodesis in children.

The study aim was to compare methods of anterior distal femoral hemiepiphysiodesis (ADFH) for treatment of fixed knee flexion deformities in ambulatory children with neuromuscular conditions and flexed knee gait. This is a retrospective review of 47 children (14 female, 33 male, age at surgery: 12.1 ± 2.7 years) who underwent ADFH between 2009 and 2016. Subjects were grouped by ADFH construct: one transphyseal screw (N = 11), two transphyseal screws (N = 28) or plates and screws (P/S group, N = 8). Clinical/radiographic variables were analyzed using paired t tests, χ tests, multiple regression and analysis of covariance. Participants experienced significant reduction in knee flexion contractures (Δ12°, P < 0.006), with no difference among groups (P = 0.43). Postoperative knee pain was significantly more prevalent in the P/S group (5/8, 63%) than the 1-SCR group (0/11, 0%) and the 2-SCR group (2/28, 7%) (P = 0.002). ADFH results in significant reduction of knee flexion deformity and improved knee extension during gait. Plate and screw constructs, the 1 and 2 transphyseal screw techniques are equally effective, but plate and screw constructs may be associated with a higher risk of persistent postoperative knee pain.

Causes of out-toeing gait in children with cerebral palsy.

BACKGROUND: Out-toeing is common in children with cerebral palsy (CP), contributing to lever arm dysfunction and functional limitations. It is important to determine the cause(s) of out-toeing prior to treatment, whether surgical or non-surgical. RESEARCH QUESTIONS: What are the contributors to out-toeing in children with CP and do they differ between children with bilateral and unilateral involvement? METHODS: The causes of out-toeing gait were determined retrospectively, with the use of computerized gait analysis, in 261 children with cerebral palsy (344 sides). The prevalence of various causes was calculated separately for children with bilateral and unilateral involvement, and compared statistically between groups using Fisher's Exact analysis. RESULTS: The most common cause of out-toeing was pes valgus in bilaterally involved subjects (71%) and pelvic external rotation (64%) in unilaterally involved subjects. Over half of the cases of out-toeing were due to multiple causes: 62% of the unilateral group and 53% of the bilateral group. In limbs with multiple causes of out-toeing in the bilateral group, pes valgus was one of the causes in 91% of limbs (146/161), and was most commonly combined with hip external rotation (27%), pelvic external rotation (22%), or external tibial torsion (20%). For the unilateral group with multiple causes of out-toeing, pelvic external rotation was one of the causes in 83% of limbs (20/24) and hip external rotation in 63% (15/24). Both were present (with or without additional causes) in 46% (11/24) of such limbs. SIGNIFICANCE: The causes of out-toeing are multifactorial in over half of affected limbs of children with cerebral palsy. They also differ for children with bilateral and unilateral involvement. These findings should be carefully considered prior to non-surgical or surgical treatment of out-toeing gait in these patients, to allow all sites of pathology to be addressed, and to optimize outcomes.

Rectus Femoris Transfer Surgery Worsens Crouch Gait in Children With Cerebral Palsy at GMFCS Levels III and IV.

BACKGROUND: Previous study has shown that children with cerebral palsy (CP) functioning at Gross Motor Function Classification System (GMFCS) levels III and IV do not benefit from distal rectus femoris transfer (DRFT) due to lack of improvement in stance knee extension. The fate of knees in such subjects who do not undergo DRFT is unknown. The purpose of this study was to compare knee kinematic outcomes in patients with CP and stiff knee gait who underwent single-event multilevel surgery with and without DRFT. METHODS: Preoperative and postoperative gait analysis data were retrospectively reviewed for ambulatory (GMFCS levels I to IV) patients with CP with crouch and stiff knee gait whom underwent single-event multilevel surgery, including hamstring lengthening either with DRFT (N=34) or without DRFT (N=40). Statistical analyses included t tests and χ tests, and multiple regression analysis was performed to adjust for covariates. Data were stratified by GMFCS level groups I/II and III/IV. RESULTS: Improved maximum knee extension in stance was seen for both the DRFT (P=0.0002) and no DRFT groups (P≤0.0006) at GMFCS levels I/II, and the no DRFT group at GMFCS levels III/IV (P=0.02). Excessive stance knee flexion persisted for those at GMFCS level III/IV after DRFT. Maximum knee flexion in swing was maintained after DRFT, but significantly decreased in the no DRFT group (P<0.002) for both GMFCS groups. Change in total knee range of motion improved after DRFT only in the GMFCS I/II group subjects with unilateral involvement (P=0.01). Timing of maximum knee flexion in swing improved for all patients regardless of DRFT or GMFCS level group (P<0.0001). CONCLUSIONS: In patients with CP functioning at GMFCS levels III and IV, DRFT results in persistent crouch postoperatively. Given the importance of maintaining upright posture in these patients, we do not recommend DRFT in patients functioning at GMFCS levels III and IV. LEVEL OF EVIDENCE: Level III-retrospective comparative study.