Can biomechanical variables predict improvement in crouch gait?

Abstract

Many patients respond positively to treatments for crouch gait, yet surgical outcomes are inconsistent and unpredictable. In this study, we developed a multivariable regression model to determine if biomechanical variables and other subject characteristics measured during a physical exam and gait analysis can predict which subjects with crouch gait will demonstrate improved knee kinematics on a follow-up gait analysis. We formulated the model and tested its performance by retrospectively analyzing 353 limbs of subjects who walked with crouch gait. The regression model was able to predict which subjects would demonstrate ‘improved’ and ‘unimproved’ knee kinematics with over 70% accuracy, and was able to explain approximately 49% of the variance in subjects’ change in knee flexion between gait analyses. We found that improvement in stance phase knee flexion was positively associated with three variables that were drawn from knowledge about the biomechanical contributors to crouch gait: i) adequate hamstrings lengths and velocities, possibly achieved via hamstrings lengthening surgery, ii) normal tibial torsion, possibly achieved via tibial derotation osteotomy, and iii) sufficient muscle strength.

Primary and secondary gait deviations of stroke survivors and their association with gait performance

“…The normalized kinematic profiles of the primary deviation of the stroke patients were moderately or highly correlated with those of the control group, but the RoMs were significantly reduced, which were in agreement with previous studies6, 8,9,10, 26 ) . The reduced RoMs at the primary joints can be explained by the fact that crouch gait, which is caused by weakness of the triceps surae muscle, makes the progression of the tibia during MST excessive, yielding excessive knee flexion from IC to MST.…”

“…Various symptoms can arise because of this pathology, such as crouch gait, stiff-knee gait (SKG), and genu recurvatum with altered excursion and a reduced range of motion (RoM) of the lower limb joints6,7,8,9,10 ) . Crouch gait is defined as excessive knee flexion in the initial phase of gait due to weak hip extensors, knee extensors, or ankle plantar flexors8, 11, 12 ) .…”

“…Various symptoms can arise because of this pathology, such as crouch gait, stiff-knee gait (SKG), and genu recurvatum with altered excursion and a reduced range of motion (RoM) of the lower limb joints6,7,8,9,10 ) . Crouch gait is defined as excessive knee flexion in the initial phase of gait due to weak hip extensors, knee extensors, or ankle plantar flexors8, 11, 12 ) . SKG is characterized by significantly diminished and delayed knee flexion during the swing phase and is mainly caused by the spasticity of the rectus femoris muscle, weakness of the hip-flexor muscle, and over-activity of the ankle plantar flexor, which lead to an inefficient gait pattern10, 13, 14 ) .…”

Musculoskeletal Simulation for Assessment of Effect of Movement-Based Structure-Modifying Treatment Strategies

“…Most of the research projects focused on the in vivo estimation of joint kinematics and muscle forces during motion [1][2][3][4][5][6]. Such information could be of great clinical interest to objectively evaluate the mechanical functions of the musculoskeletal system in normal as well as in pathological conditions [7][8][9]. In the case of orthopedic device prescription especially, the joint kinematics and muscle force information could allow an optimal design to be performed leading to maximizing the benefit of the involved patient [10,11].…”

Bilateral sleeve fractures of the patella in a 12-year-old boy with hereditary spastic paraparesis and crouch gait

“…Crouch gait is a walking pattern characterised by excessive flexion of the knee during stance and is common in cerebral palsy (CP) 1. Hereditary spastic paraparesis (HSP) is not classically associated with crouch gait.…”