Is it unusual to observe athletes who weigh this much or more? why or why not?

CONCLUSION

Gait analysis has had a long history and for much of this time it has remained an academic discipline with little practical application. This situation has now changed and the value of the methodology has been unequivocally demonstrated in certain conditions, particularly cerebral palsy. We are already seeing a decrease in the cost and complexity of kinematic systems and an increasing acceptance by clinicians of the results of gait analysis. This trend will hopefully continue, so that the use of these techniques will increase, both in those conditions for which its value is already recognized and in a variety of other conditions.

Although the current text has focused on gait analysis, this type of measurement equipment may also be used for other purposes – a fact which may be relevant to those trying to obtain funds to set up a gait analysis laboratory! The use of force platforms and kinematic systems for balance and posture testing has been referred to, as has their use in studying performance in a wide range of sports. Clinical studies have also been made of people standing up, sitting down, starting and stopping walking, ascending and descending stairs. The equipment has been used to measure the movements of the back, not only in walking but also in the standing and sitting positions. It has also been used to monitor the movements of the upper limbs, both in athetoid patients and in ergonomic studies of reach. Walking is only one of many things which can be done by the musculoskeletal system. It is only sensible to broaden our horizons and to use the power of the modern measurement systems to study a wide range of other activities.

Gait Analysis

Gait analysis using three dimensional (3D) systems is currently the gold standard for measuring parameters including spatiotemporal variables and joint kinematics.56 Such information may be useful when considering rehabilitation options or during complex clinical decision making. In a study by Ochi et al., 172 TBI patients completed gait analysis measures. Analysis of gait parameters demonstrated reduced walking speed, with a prolonged stance phase and shorter step length for the unaffected limb.24 Additionally, a systematic review of biomechanical abnormalities during gait following TBI identified 38 studies of relevance. All included studies demonstrated participants had reduced gait speed seemingly secondary to a smaller step length.56 Data on gait kinematics remains sparse, although this may be more relevant to those with a more severe brain injury. Although such data may be useful to guide rehabilitation, there remains no prospective data regarding the predictive ability of 3D gait systems and long-term recovery, or functional outcomes such as falls.

Introduction

Gait analysis in the clinical setting is a valuable part of decision making when initially assessing a child and when reviewing their progress and the effects of any treatments. Normal paediatric gait is complex, but abnormal gait is even more complex as seen in children with cerebral palsy. These children are best assessed with 3-D motion measurement in a gait laboratory, as this gives best diagnosis and therapeutic planning, be this surgical or orthotic in nature. However, the clinician must be able to observe gait simply and make qualitative judgements about a child's gait based on the visual appearance and noting the following factors:

balance

stability

speed

movement control

symmetry

limb and trunk motion

weight transfer

foot type and placement.

(Rose et al 1991).

Observation gives valuable information about a child's overall walking pattern and their ability to function. Video gait analysis can be useful to review features without the child being present and to save protracted gait observation.

Key Concepts

The clinician should be aware that gait on a treadmill is usually quite different to normal gait and observed gait may differ from usual gait. The use of a walkway is therefore recommended.

The history of gait analysis began in Europe in the 17th century and continues to evolve and embellish our current understanding of human walking (Sutherland 2001, 2002). Sutherland has been one of the notable contemporary investigators of paediatric gait, in association with many other prominent scientists, and the reader is directed to this work for greater understanding of this area (Cusick 1990; Gage 1993; Perry 1992; Rose et al 1991; Sutherland 1978, 2001, 2002).

GAIT ASSESSMENT

Gait analysis must be conducted in order to determine what gait deviations and/or problems are present. There are many valid and reliable gait assessment tools that are appropriate for use with the older client. Observational gait analysis is routinely performed by clinicians and refers to the use of qualitative methods to assess gait deviations (McGinley et al 2003, Ranchos Los Amigos National Rehabilitation Center 2001). Other gait assessment methods utilize measures of distance, stability and time (see Table 69.2). Assessment of gait speed is important as it has been shown to be the single best predictor of disability and frailty among older adults (Guralnik et al 2000).

When assessing gait, the healthcare provider must consider that many specific pathologies (orthopedic, neurological, biomechanical, cardiopulmonary) may contribute to gait deviations, and that the typical elderly client usually presents with multiple problems. Individual pathologies (i.e. stroke, Parkinson's disease, etc.) may result in a typical pattern of gait deviation, but many elderly adults have one or more common gait deviations.

The International Classification of Diseases, 9th edition (ICD-9) recognizes the existence of gait abnormalities that have causes that cannot be clearly determined but that produce symptoms that represent important problems in medical care. The ICD-9 codes include code 781.2 Abnormality of Gait, which describes ataxic, paralytic, spastic or staggering gait patterns. The code 719.7 Difficulty in Walking is appropriate to use for individuals who demonstrate a limp or related problems during gait that are due to unspecified disorders of the pelvic region, thigh, lower leg, ankle and foot. Both codes may be appropriate to describe the gait conditions for which many elderly people require training.

Gait Analysis

Gait analysis can be as simple as observational screening to note abnormalities detectable by the naked eye. Systematic gait analysis incorporating a top-down and bottom-up visual orientation is optimal when investigating subtle deviations. A top-down orientation provides data on symmetry, quantity, and quality of arm swing; pelvic rotation; pelvic tilt; and lateral trunk shift. Next, knee and lower leg motions are observed. The bottom-up orientation provides assessment of ankle, subtalar, midfoot, and hallux motion symmetry, quantity, and quality. The observer studies this top-down and bottom-up gait assessment with focus of potential exaggerated motion or insufficient ability of the locomotor unit to provide propulsion, stance stability, shock absorption, and energy conservation. Core postural muscle instability is suspected when excessive pelvis crest drop and pelvic rotation are observed. Further testing of gluteal muscle function in open and closed kinetic chain positions would be warranted. Excessive hip adduction with knee valgus producing an increased dynamic quadricep angle is a significant observation. Knee varus trust defined as a lateral knee shift may be indicative of lateral knee complex instability or osteoarthritis of the medial knee compartment. Early heel rise during propulsion is a common compensation for hallux limitus, sesamoiditis, or ankle equinus. Dananberg and Guiliano30 describe a relationship between hallux limitus and spine pain related to deficient hallux extension in late stance phase when walking. A contralateral increased lateral shift is described as the lower extremity adapting to the loss of hallux extension with the concomitant decrease in hip extension at midstance. Spine pain patterns are related to the hallux limitus, and Dannenberg and Guiliano30 describe a 36% improvement with custom foot orthotics described to neutralize the deleterious effects of hallux extension loss.

Excessive foot pronation is visualized by three potential observations: excessive calcaneal eversion, medial midfoot collapse, and excessive toe out. Abnormal foot supination is visualized by calcaneal inversion, excessive medial midfoot arch height, and disproportionate weight bearing on the lateral foot. Large callus formation may develop under the first and fifth metatarsal heads. Excessive toe-out posturing in stance phase may represent compensation for hallux limitus, ankle equinus, excessive tibial external torsion, or excessive foot pronation. Toe-out walking patterns place increased medially directed elongation stresses and laterally directed compressive stresses along the soft tissues of the ankle joint. Excessive toe-in posturing in stance phase represents most commonly metatarsus adductus or excessive tibial internal torsion. Gait assessment of running includes all of those previously described with attention given to initial foot strike. First foot contact may be observed at the calcaneus, midfoot, forefoot, or toes. Early-stance phase heel strike enables ankle joint dorsiflexion and foot pronation to provide weight-bearing loading and shock absorption. Forefoot and toe strike as the initial foot contact is the norm in running sports' requirement for speed and change of direction. Prolonged straight-ahead running with forefoot and toe strike as the initial contact relates to decreased shock absorption capability.

Clinical single-camera videotaping during observational gait analysis provides a significant tool both for assessment and patient instruction. Video captures 60 images per second compared with the naked eye, which can capture only 4 to 6 images per second.22 Immediate playback provides pause frame and advance abilities enhancing clinical study and patient feedback. Instrumented gait analysis systems include motion analysis, dynamic electromyography, and force plate measurement. Motion analysis systems are designed to define the magnitude and timing of individual joint action. Dynamic electromy-ography provides muscle function data defining timing and contraction intensity. Force plate systems measure weight-bearing loading characteristics.

Gait analysis

Gait analysis is a way to assess the dynamic posture and coordination during movement. This analysis is a means to evaluate, record, and make any necessary corrections for a smooth gait. During this analysis the therapist needs to note the minor shifts in movement such as rotations and tilts or knee movement and foot placement. These movements can help lead the therapist to potential issues with flexibility and muscle strength. Identifying hypermobile or hypomobile movements at the joints, whether or not the movement varies from side to side, can help identify proprioceptor and neuromuscular concerns. Assessing any deviations or inconsistencies can be a clue to potential restrictions.

Be aware of your surroundings when performing a gait assessment. The client will become more conscious of his or her movements when you ask your client to walk for you. This altered motion caused by the client's awareness of being assessed may create false information. One recommendation is to have the client do some of the other assessments first and use the gait to fine tune your assessment. You can also observe your client while he or she is walking into your massage space, or as you guide him or her to your table.

Gait and posture may be affected by a number of factors that should be included in your findings. Structural deformations, wear and tear, previous injuries, and other findings can affect the way the body moves and the fluidity of the gait. The client's age, height, gender, and total body weight are all variables that also lead to understanding where the pain and dysfunctions originate.

Gait analysis

Gait analysis is a very important part of the assessment process (Kakushima et al 1999). Normal findings include a smooth transition of weight with equal movement from one side to another as the weight is transferred from one leg to the other during gait. An abnormal and very common finding in patients with AOS is an abrupt or excessive motion of the pelvis during stance phase, for example, the abrupt drop in the frontal plane of the left side of the pelvis during stance phase on the right. This translates to asymmetrical loading (overloading) in the frontal plane and the abruptness of the motion creates increased load and greater chances for injury. It is very difficult to successfully treat patients (i.e. unload the affected area) who cannot tolerate backward bending and side bending to the right in the low lumbar spine when they walk, as previously described. The loads directed to the spine in backward bending and side bending to the right are similar to those converging into the lumbosacral region as the pelvis drops down on the left during right stance. Backward bending and side bending replicate the converging loads from above down; the frontal plane drop seen during gait is from below up.

The pelvis dropping down to the left during right stance creates backward bending and side bending to the right from below up at the low lumbar spine. This is the key: to develop a three-dimensional appreciation of the anatomy and to be able to assess the overload from above down and from below up.

Excessive pronation of the rear and midfoot is also viewed while watching a patient walking briskly. The examiner is looking for asymmetry while evaluating the extent of genu valgus and tibial rotation during stance. Genu valgus alters the weight bearing of the hip and low back and can play a role in causing overload.

Analyzing gait with and without the correction also often reveals differences. The difference with adding a heel lift is a smoother less abrupt movement during the transition of weight from side to side, especially in those patients who, during the evaluation, describe a greater comfort while standing on a calibrated block.

Patient Walking

•

Gait analysis (Fig. 3.1) entails observing the patient walking to detect abnormalities in the motor system or musculoskeletal structures that are more pronounced during walking.

If possible, observe the patient's gait when he or she is not aware of being evaluated, such as when the patient is being escorted to the examination room.

Otherwise, observe the patient's gait by having him or her walk the length of the examination room several times.

Observe any abnormalities in the length of stride, arm swing, heel strike, and toe off; pelvic tilt; or any limping. Asking the following questions while observing may be helpful:

Is the weight transferred in a smooth manner from heel strike to toe off?

Do the toes point inward or outward?

Is there excessive pronation or supination of the feet?

Is there internal or external rotation of either leg?

Abnormal gait may signify neurologic or musculoskeletal problems that require further regional and segmental evaluation.