Features Practice Technique
Essentials of Assessment: Winter 2004

One of the most important observations that a massage therapist can make, next to a static posture assessment, is assessing the client in motion. And walking is one of the motions that if a person cannot do society often labels that person as disabled. Further, only slightly behind lower and upper back and cervical pain as a chief complaint is pain arising from the feet, knees and hips; which, of course, affect lower and upper back and cervical functioning. Hence, massage therapists need to be able to do a basic scanning assessment of gait – a global picture of gait – that gives clues to where to look and test more specifically for the causes of pain and dysfunction during and after walking. The specific testing is done by range of motion testing, differential muscle testing, and any appropriate special tests.

Every standard text on general orthopedic testing will have the basic information on the terms employed for such an analysis of walking. The classic division and subdivisions are, of course:

Stance Phase
• heel strike
• foot flat
• single leg stance
• heel off
• toe off

Swing Phase
• initial swing (acceleration)
• mid swing
• terminal swing (deceleration)

This article will provide a global, generalized look at gait, with a focus on the soft tissue structures involved. Of course, this means that experts in this field will find generalizations and/or ‘errors’ (often due to over-simplification).

This is presented as a first draft at trying to summarize what is occurring during walking and to help massage therapists know where to focus, literally, their eyes when the client is walking, to the treatment room, or during a formal gait analysis where the client is asked to walk barefoot back and forth several times.

Remember, just like a standing postural assessment, try to get as many views from various directions as possible. Also, do not try to see everything at once. First, look at the feet as they walk back and forth, then note the knees as they walk back and forth. Then the hips … Now watch all areas working together.

Just before giving the summary, we need to understand a term often used to describe an import function of the foot during gait: “the windlass effect.” (A term which apparently comes from sailing.) This term has to do with the changes in tension on the plantar ligaments of the foot as it enters, holds and leaves the stance (weight bearing) phase of walking.

The arch of the foot is not meant to be rigid and inflexible. Rather, it is designed to mould to the ground or surface it is walking or standing on.

As will be mentioned below, when the heel strikes the ground the foot is lowered under control of the tibialis anterior muscle, working eccentrically. The ligaments of the foot will soften, allowing the arch and the bones of the foot to mould to the surface they are on. Then, as the foot moves to ‘toeing off’ these ligaments will tighten as the arch leaves the ground in order to fix the arch so that the maximum amount of the mechanical energy of the plantar muscles flexing goes into moving the body forward.

To see that this works to our mechanical advantage we need only talk with those who have an arch or two that have fallen. They lose mechanical efficacy and, hence, not only does the foot have aches that pain from the joints and ligaments of the foot, but further, the plantar muscles need to work extra hard to walk and so tire easily and often are a source of great discomfort to the client during or after walking some distance. (Or, at least, when their massage therapist applies even light pressure on their calves during a massage!)

Stance Phase: Closed Kinetic Chain
1. Phase: Heel Strike a.k.a. loading response moving towards foot flat

Soft Tissue Actions
Tibialis anterior eccentrically controls the lowering of the foot. The externally rotated tibia begins internally rotating and causes the hind foot (the subtalar joint) to pronate while the tibialis anterior still holds the forefoot (the tarsals, metatarsals & phalanges) in supination. This causes the ligaments of the foot and the plantar aponeurosis to go slack – to untwist the foot – so that it can accommodate to the ground, thus allowing the foot to absorb the shock of hitting the surface it is walking on.

Problems
Foot slap occurs if the tibialis anterior is weak or inhibited. Heel spurs will cause a person to avoid heel strike and come down flat of their foot or on their toes. Extension lag or the inability of the quadriceps to extend the knee will cause the client to come down on a flat foot – the tibia will not internally rotate and so the foot will not untwist in order to accommodate itself to the ground.

2. Foot Flat moving towards midstance

Soft Tissue Actions
The tibia continues internal rotation as the foot moulds to the ground. The forefoot will now begin to pronate. (Full pronation of the medial longitudinal arch begins.) The plantar flexed ankle (plantar flexed as it is ahead of the rest of the leg) now starts to dorsiflex as the tibia begins to come over the foot. The hip also begins to extend, from its flexed position, to bring the trunk forward and the once externally rotated (at heel strike) hip starts to internally rotate as well (N.B. Internal rotation that started at the hind foot has now reached all the way up the leg).

Problems
A fixed ankle from joint swelling or for any reason that leads to decreasing the range of motion of the ankle mortise joint will mean the foot cannot plantarflex and therefore mean the foot can not weight bear till midstance.

3. Midstance
Soft Tissue Actions
The body moves over the stance leg: When the hip is extended to 10 degrees, the once-straight, but unlocked knee begins to flex. The tibia now begins to externally rotate which means the hind foot begins to supinate while the forefoot is still pronated (N.B. the opposite of when the foot ‘untwisted’ above). And the foot begins twisting. This is the beginning of what is known as the windlass effect: the ligaments of the foot begin to tighten as they twist

Problems
Pain will be present with a rigid/ structural pes planus. Over pronation of the foot will also occur with a lax or functional pes planus. A loss in the transverse arch may lead to corns, calluses or neuromas which will cause pain during weight bearing. Trendelenburg Gait: Weak hip abductors will cause the swing leg’s hip to drop, or have the person sidebend over the stance leg to hold up the swing leg. Gluteus Maximus lurch: is a backward lurch of the trunk to bring the hip into extension.

4. Pushoff a.k.a. Heel Off and/or Toe Off centre of gravity rises 2”
Soft Tissue Actions
The ankle plantar flexes and the weight on the foot moves to the first toe. As the metatarsalphalangeal joints extend and the windlass effect comes into full force: The aponeurosis is pulled tight as the foot toes off. The foot has now become a rigid lever. This leads to maximum efficiency of the plantarflexors to thrust the body forward. The hip begins to flex. The knee has flexed to its maximum during stance phase, to 50/60 degrees.

Problems
Gastronemuis-soleus (S1) weakness will prevent efficient toe off. So the client will not so much push off on a flat foot as lift the foot prematurely using hip and knee flexors as well as elevators of the ipsilateral hip. A rigid first toe metatarsalphalangeal joint will also prevent the client from toeing off, but will instead go off the lateral side of the foot, or even off the whole foot A fallen arch does not permit the ‘twisting’ of the intrinsic ligaments of the foot and arch – windlass effect – and so some of the force of push off is lost. The gastroc-soleus tire easily.

Swing Phase: Open Kinetic Chain

1. Acceleration a.k.a. Initial swing
Soft Tissue Actions
The ankle dorsiflexes to help the foot clear the ground as it swings forward. The knee is flexed to 65 degrees to help the foot clear. The hip flexors are engaged to throw the leg forward. This helps the hip to complete its internal rotation.

Problems
Hip flexor weakness (L2) will cause the client to lurch backwards to use tissue stretch to help throw the leg forward.

2. Midswing
Soft Tissue Actions
Hip becomes flexed and remains medially rotated and often now becomes slightly raised as well: all of this assists the foot to clear the ground. While the knee remains flexed the ankle joint returns to neutral which leads to an unlocking or untwisting of the metatarsal joints (the forefoot).

Problems
Steppage Gait: Tibialis anterior (L4) is unable to hold the foot dorsiflexed so client excessively flexes the knee to help the foot to clear the ground.

3. Deceleration a.k.a. Terminal swing centre of gravity has dropped
Soft Tissue Actions
The hip began to externally rotate as it moved from midswing. Hip reaches its maximum flexion 30/40 degrees. The hamstrings are now eccentrically engaged to slow down the forward momentum of the leg. This provides a ‘soft landing’ for the heel. As the knee moves to become fully extended (but unlocked), the tibia externally rotates. Hence the hind foot goes into supination as does the forefoot.

Problems
Weak hamstrings (S2) are unable to eccentrically slow the leg from its forward swing in time: the heel will strike the ground hard, with a thump.

Using this model and understanding the changes that the soft tissues and joints undergo will help the massage therapist be able to see what area(s) of the lower body are affected. Now specific detailed testing and grading of the affected tissues can take place with confidence and yield the most beneficial information on which to arrive at a treatment plan. Enjoy your walk!

References
For gait in general see:

• Stanley Hoppenfeld. Physical Examination of the Spine and Extremities. Norwalk: Appleton-Century-Crofts, 1976.
• Magee, David J., Orthopedic Physical Assessment, 2nd Ed., W.B. Saunders Co., 1992.

For gait and the role and actions of various areas of the body see:

• Kisner, C. & Colby, L., Therapeutic Exercise Foundations and Techniques, 3rd Ed., F.A. Davis, Philadelphia, 1996.

For the ‘windlass effect’ see:

• Herting, D., & Kessler, R. M., Management of Common Musculoskeletal Disorders: Physical Therapy Principles and Methods, 3rd Edition, Lippincott, Philadelphia, 1996