Relationship between radiographic patella-alta pathology and walking dysfunction in children with bilateral spastic Cerebral Palsy

Morphology and transverse alignment of the patella have no effect on knee gait characteristics in healthy Chinese adults over the age of 40 years

Background: The influence of patella morphology and horizontal alignment on knee joint kinematics and kinetics remains uncertain. This study aimed to assess patella morphology and transverse alignment in relation to knee kinetics and kinematics in individuals without knee conditions. A secondary objective was to investigate the impact of femur and tibia alignment and shape on knee gait within this population. Patients and methods: We conducted a prospective collection of data, including full-leg anteroposterior and skyline X-ray views and three-dimensional gait data, from a cohort comprising 54 healthy individuals aged 40 years and older. Our study involved correlation and logistic regression analyses to examine the influence of patella, femur, and tibia morphology and alignment on knee gait. Results: The patellar tilt angle or the patella index did not show any significant relationships with different aspects of gait in the knee joint, such as velocity, angle, or moment (p > 0.05, respectively). Using multivariate logistic regression analysis, we found that the tibiofemoral angle and the Q angle both had a significant effect on the adduction angle (OR = 1.330, 95%CI 1.033-1.711, p = 0.027; OR = 0.475, 95%CI 0.285-0.792, p = 0.04; respectively). The primary variable influencing the knee adduction moment was the tibiofemoral angle (OR = 1.526, 95% CI 1.125-2.069, p = 0.007). Conclusion: In healthy Chinese individuals aged over 40, patella morphology and transverse alignment do not impact knee gait. However, the femoral-tibial angle has a big impact on the knee adduction moment.

Relationship between spatiotemporal parameters and clinical outcomes in children with bilateral spastic cerebral palsy: Clinical interpretation proposal

BACKGROUND

Understanding the links between gait disorders, impairments, and activity limitations is essential for correctly interpreting the instrumented gait analysis. We aimed to evaluate the relationships between spatiotemporal parameters and clinical outcomes in children with bilateral spastic cerebral palsy, and find out whether spatiotemporal parameters provide clinical information regarding gait pattern and walking.

METHODS

Data from 19 children with bilateral spastic cerebral palsy (nine males, ten females, 9.6 ± 2.8 years old) were collected retrospectively. All children underwent an instrumented gait analysis and a standardized clinical assessment. Seven spatiotemporal parameters were calculated: non-dimensional cadence, stride length, step width, gait speed, first double support, single support, and time of toe off. Clinical outcomes included measures of two different components of the International Classification of Functioning, Disability and Health - Children and Youth version: body functions and structures (spasticity, contractures and range of motion, and deformities), and activities and participation (gross motor function, and walking capacity). Pearson correlation, ANOVA, Student's t, Mann-Whitney U, and Kruskal-Wallis tests were used to analyze relationships. Spatiotemporal parameters related to clinical outcomes of body functions and structures were interpreted as outcome measures of gait pattern, while those related to clinical outcomes of activities and participation were interpreted as outcome measures of walking.

RESULTS

Non-dimensional cadence, stride length, and gait speed showed relationships (p < 0.05) with hip flexors spasticity and hindfoot deformity, ankle plantar flexors spasticity, and hindfoot deformity, respectively. All spatiotemporal parameters except non-dimensional cadence showed correlation (p < 0.05) with gross motor function and walking capacity.

CONCLUSIONS

Spatiotemporal parameters provide clinical information regarding both gait pattern and walking.

What happens to the patella height in patients with cerebral palsy as they age

We aimed to investigate the progression of patella alta (PA) in patients with cerebral palsy (CP) using the Koshino-Sugimoto (KS) index and assess associated risk factors. Participants in our retrospective study met the following inclusion criteria: patients with CP who visited our institute from May 2003 to December 2019, were ≤18 years of age, were followed up for >2 years and had at least two lateral knee radiographs. KS indices of both knee radiographs were measured for each patient. A linear mixed model was implemented. Our participants included 222 CP patients. KS index values were measured via 652 knee radiographs. Reference values of the KS index for those between 4 and 18 years of age were determined according to Gross Motor Function Classification System (GMFCS) levels. In all GMFCS levels, the KS index decreased with patients' ages (P < 0.0001). In groups where the KS index increased, GMFCS levels IV (P = 0.0045) and V (P = 0.0040) were statistically significant. Change in the KS index values indicates that PA improves as patients age within all GMFCS levels. However, in patients with GMFCS levels of IV and V, progressive PA is expected.

Patella Alta in Ambulatory Children With Cerebral Palsy: Prevalence and Functional Significance

BACKGROUND

Gait dysfunction associated with patella alta (PA) in subjects with cerebral palsy (CP) has been presumed but not objectively established clinically or through biomechanical modeling. It is hypothesized that PA is associated with increasing level of motor impairment, increasing age, obesity, and worse stance phase knee kinematics and kinetics in children with CP.

METHODS

Retrospective case series of 297 subjects with CP studied in our Motion Analysis Center. Data analyzed included patient demographics (age, body mass index, CP classification), patella height (Koshino-Sugimoto Index), and knee kinematics and kinetics.

RESULTS

PA was present in 180 of 297 subjects (61%), in 68 of the 146 (47%) with unilateral CP, and 112 of 151 subjects (74%) with bilateral CP. For unilateral CP, the prevalence of PA was not significantly different between Gross Motor Function Classification System (GMFCS) I and II (P=0.357). For bilateral CP, the prevalence of PA in GMFCS III was significantly greater than in GMFCS I and II (P=0.02). Regression analysis showed a significant trend between increasing age and PA in unilateral and bilateral groups (P<0.001 and 0.001, respectively). The prevalence of PA was not significantly different across body mass index categories for either unilateral or bilateral groups. There were only 2 of 10 significant correlations between PA and gait parameters for subjects with unilateral CP functioning at the GMFCS I and II levels. There were 8 of 12 significant correlations between PA and gait parameters for subjects with bilateral CP functioning at the GMFCS I, II, and III levels.

CONCLUSIONS

PA is common in ambulatory children with CP across topographic types and motor functional levels. PA is well tolerated with respect to gait dysfunction in unilateral CP, but may contribute to crouch gait in bilateral CP. Gait dysfunction cannot be inferred from the radiographic assessment of patellar height, and radiographic evidence of PA by itself does not justify surgical correction with patellar tendon advancement or shortening.

LEVEL OF EVIDENCE

Level III-prognostic, retrospective series.

Evaluation of infrapatellar tendon plication in spastic cerebral palsy with crouch gait pattern: a pilot study

OBJECTIVE

In order to substantially improve crouch pattern in cerebral palsy, the existent patella alta needs to be addressed. This pilot study evaluates the effectiveness of a previously described infrapatellar tendon plication for the treatment of patella alta in crouch gait pattern in skeletally immature spastic cerebral palsy patients.

METHODS

In 10 skeletally immature patients (20 knees) with spastic diplegia and crouch gait, the previously described technique by Joseph et al. for infrapatellar tendon plication was evaluated within the setting of single event multilevel surgery (SEMLS). Outcome measures included knee extension lag, Koshino's radiological index for patella alta, and the occurrence of complications. Patients were followed-up for a minimum of 12 months.

RESULTS

The extensor lag improved and was statistically significant in all cases of the study with no incidence of tibial apophyseal injury at the latest follow-up. Radiographic Koshino index normalized and was maintained all through the follow-up period except in one patient (5%) who was overcorrected. Two patients (4 knees, 20%) showed postoperative knee stiffness due to casting which resolved with physiotherapy within six weeks. One knee (5%) developed a superficial infection which also resolved uneventfully with repeated dressings.

CONCLUSION

The described infra-patellar plication technique in skeletally immature spastic diplegics appears effective, safe, and reproducible.

Musculoskeletal Imaging in Cerebral Palsy

Scoliosis, hip dysplasia, and other lower extremity deformities are common musculoskeletal pathology found in patients with cerebral palsy. Imaging studies allow for an improved identification of patients with these issues, help to understand the pathology, and aid in planning treatment strategies. Most of these deformities are visualized using plain radiographic techniques. Occasionally, as in the case of preoperative planning, advanced imaging, such as computerized topography and MRI, can be used for additional information. This article provides insight into the various imaging techniques for these musculoskeletal issues and aids in better care for patients with cerebral palsy.