Editor's note: Part 1 of this article appeared in the Oct. 21 issue.
If the proprioceptive system is malfunctioning because of repeated malfunctioning due to the repeated microtrauma associated with a mechanical malfunctioning foot, then a flexible, supportive orthotic should be considered an appropriate recommendation. An orthotic should be considered in an attempt to improve the mechanical efficiency of the supporting muscles, which lessens the irritation of the abnormally stressed joints. The custom-made orthotic can also re-establish the normal progression of forces along the plantar surface of the foot. By improving the progression of forces, the orthotic re-educates the central nervous system to the ideal patterns for muscular recruitment.
Novak and Kelly suggest orthotic intervention can reduce calcaneal eversion, which will result in improved tactile and proprioceptive feedback during dynamic function.1 Recently Nigg, et al., proposed that proprioceptive enhancement may actually be the most important criteria in defining success of orthotic applications.2 And a study by Stude and Brink suggests a positive link between the use of foot orthoses and enhancements in balance performance and fatigue reduction.3
A recent study by Cobb examined the effect of six-week use of custom-molded foot orthoses on postural stability in individuals with 7 degrees or less of forefoot varus. The study noted significant improvements in postural stability in participants who wore foot orthotics.4 The effects of postural stability relate to sway and may positively impact the risk of falling in the elderly population. Further studies are warranted to enhance our knowledge of the proprioception system and the best ways to positively influence this system to enhance patients' health recovery from trauma and improve their sense of wellness.
In addition to foot orthoses and manipulation to improve proprioception, proprioceptive neuromuscular facilitation (PNF)exercises could also be applied with good results.5 One method a clinician could use is the PNF pattern: requiring the patient to alternately plantarflex and invert the forefoot and dorsiflex and invert the forefoot against resistance provided by the clinician. An alternative pattern would be to have the patient alternate between plantarflexing and inverting one foot while the opposite foot is dorsiflexing and everting. The foot that is plantarflexing is maintained with the lower extremity in an externally rotated position, while the opposite lower extremity is internally rotated.
A simple and effective method for retraining proprioception is with the use of a balance board. This training must begin simply and progressively become more difficult with increased challenges to the patient. A simple and effective approach to balance-board training could begin with the patient sitting using both feet simultaneously. Initially, the patient could move from dorsiflexion movements to turning the board 45 degrees left and 45 degrees right, and finally to inversion and eversion. The next phase could have the patient repeat the sequence, except this time using a single-leg motion during the process.
The patient could then assume a standing posture and again use both feet on the balance board to follow the same protocol. It would be prudent for the clinician to spot the patient through this process and have a grab bar present to prevent falls and ensure patient safety. To continue, simply follow the same process, except now maintain single-leg balance with the board in a central position, without the ends of the board touching the floor.
There are many variations to this procedure, such as having the patient continue with their eyes closed or having them perform simple activities while on the balance board. An example might be to have them toss a ball from hand to hand while maintaining balance, or have them catch and toss a ball to an assistant or into a rebounder. Another variation would be to gently perturb the patient while they are attempting to maintain balance.
Each session could last between three and five minutes, depending on the patient's stamina and ability. The level of difficulty could be increased based on the patient's ability to perform the exercises and subjective reports of ability to progress. The goal is to increase the proprioceptive effects in restoring kinesthetic awareness by stressing the proprioceptive pathways.
Following even a minor injury, compensatory movement patterns may trigger a new state of central nervous system-mediated motor control patterns. Therefore, the rehabilitation process should emphasize resolving the acute phase of injury as quickly and efficiently as possible. By minimizing healing time, decreasing the effects of scarring and maintaining or restoring normal range of motion, you reduce the opportunity for the patient to develop altered movement patterns, which have the potential for further injury and increasing abnormal involvement of the neuromuscular and proprioceptive systems.
References
- Novick A, Kelly DL. Position and movement changes of the foot with orthotic intervention during the loading response of gait. J Orthop Sports Phys Ther, 1990;11(7):301-312.
- Nigg BM, Nurse MA, Stefanyshyn DJ. Shoe inserts and orthotics for sport and physical activities. Med Sci Sports Exerc, 1999;31(suppl):s421-8.
- Stude DE, Brink DK. Effects of nine holes of simulated golf and orthotic intervention on balance and proprioception in experienced golfers. J Manipulative Physiol Ther, 1997;20:590-601.
- Cobb SC, Tis LL, Johnson JT. The effect of 6 weeks of custom molded foot orthoses intervention on postural stability in participants with OR = 7 degrees of forefoot varus. Clin J Sport Med, 2006 Jul;16(4):316-22.
- Voss DE, Ionta MK, Myers BJ. Proprioception Neuromuscular Facilitation. 3rd Edition. Philadelphia: Harper & Row, 1985.
Dr. Manuel Duarte is a graduate of National College of Chiropractic and a diplomate of the American Chiropractic Board of Sports Physicians and the American Board of Chiropractic Orthopedics. He has extensive teaching experience and lectures on a variety of topics, including manual treatment procedures, rehabilitation, orthopedics, and sports medicine.