Orthosis Overview

1. Orthosis Overview Kyle Kahl

2. Purpose • To compare rigid versus soft or flexible orthosis in the success of alleviating lower extremity injuries. • To discover whether LE injures respond better to custom-made orthosis that are formed in weight bearing stance or better when formed while non-weight bearing.

3. Problem • Orthoses research has not focused on these objectives. • Most of the literature I reviewed was concerned with how orthosis intervention affects biomechanics in the lower extremities and their efficacy.

4. History • Root et al. are responsible for much of the ground-breaking research of the 60’s and 70’s. • Great attention was focused on attaining subtalar neutral during ambulation in order to obtain a non-pathologic gait. Their original definition stated, “The subtalar joint is in the neutral position when the foot is neither supinated nor pronated.”

5. Subtalar Neutral • Conversely, McPoil and Cornwall and Pierrnowski and Smith (as cited in Ball & Afheld, 2002) found that, “in normal subjects, the motion of the subtalar joint rarely even reaches the subtalar neutral position during the stance phase of gait.” • In addition, the methods for determining this were very complicated and had poor intra-tester reliability. • Root et al. tended to bias their findings for those with supinated feet.

6. Normal Joint Coupling • 4/5 sources were consistent in the kinetic movements of calcaneal EV (or inability to invert) and IR of the talus leading to tibial internal rotation (Kelaher, Mriak, & Dudziak, 1997; Deleo, Dierks, Ferber, & Davis, 2003; & Williams, Davis, & Baitch, 2003). • All 5 mentioned TIR(Kelaher, Mriak, & Dudziak, 1997, Herel, Sloss, & Earl, 2002; Ferber, Davis & Williams, 2004; Deleo, Dierks, Ferber, & Davis, 2003, Williams, Davis, & Baitch, 2003)

7. Joint Coupling

8. Joint Coupling Continued • McClay and Manal (1998) went on to define excessive rearfoot eversion if 18 degrees of calcaneal eversion is exceeded. This leads to an alteration further up the kinetic chain, resulting in increased knee abduction and flexion from the compensating TIR. This is correlated with patellofemoral joint pain and malalignment.

9. Joint Coupling Continued • Likewise, Tiberio (1987) (as cited in Deleo, Dierks, Ferber, & Davis, 2003) developed a contention that prolonged pronation extending beyond midstance may delay a return from TIR to ER, therefore; becoming a mechanism for anterior knee pain. This can cause further joint coupling, causing the femur to internally rotate to prevent a compromised angle of patellar alignment.

10. EV vs. TIR • Rearfoot eversion (EV) and TIR can be compared as a ratio. • For example, a ratio of 2.0 would indicate that for every 2 degrees of eversion, there is 1 degree of tibial internal rotation. • McClay and Manal (1997) (as cited in Deleo, Dierks, Ferber, & Davis, 2003) found an EV/TIR ratio of 1.42 for nine healthy runners while Stacoff et al (2000) (as cited in Deleo, Dierks, Ferber, & Davis, 2003) found a ratio of 1.72 in five uninjured runners. This results in EV>TIR for the healthier runners in this small sample size.

11. EV vs. TIR: Inconsistent • Two studies directly oppose the postulations of McClay and Manal (1998): • Williams et al. (2001) reported that subjects with low arches were found to have higher EV/TIR ratios (meaning EV>TIR) as well as a greater incidence of knee injuries while those with pes cavus had low EV/TIR ratios (more TIR than the low arch group), but experienced more foot injuries. • Correspondingly, Nawoczenskie et al (1998) (as cited in Deleo, Dierks, Ferber, & Davis, 2003 and Ferber, Davis & Williams, 2004) found the same result in runners with pes cavus.

12. Joint Coupling Conclusion • Based on the research over the past 40 years concerning joint coupling being associated with injury, it is apparent that the literature conveys a high variance of results and therefore, remains highly elusive. • What can be concluded regarding joint coupling and injury can best be summarized by two studies. • Nigg et al. (1993) statistically evaluated the relationship of joint coupling and medial longitudinal arch height to see if it correlated with knee injury. The relationship was poor and insignificant, with arch height only explaining 27% of the variance in coupling. • Heiderscheit et al (2002) (as cited in Ferber, Davis & Williams, 2004) assessed joint coupling patterns between healthy and patellofemoral pain syndrome runners and found no differences except a lower variability in the patellofemoral pain group. • In other words, joint coupling patterns has been unable to consistently engender precise pathological versus non-pathological relationships in the foot and ankle joints.

13. The Efficacy of Orthoses • Despite the elusive mechanisms for orthosis intervention, the results cannot be denied. • Studies and their results reviewed

14. Large Military Study • Prospective, randomized, controlled, intervention trial. • August to November of 1999, performed on 130 Danish military conscripts. • 67 conscripts received custom-fitted (while weight-bearing) semi-rigid shoe orthoses while 63 conscripts served as the control group and had no orthoses. • The results were promising, finding significantly lower extremity and back problems from 56% in the control group compared to 36% in the intervention group. In addition, significant results were obtained for shin splints, 24% and 13% respectively.

15. Plantar Fasciitis • A study by Seligman and Dawson (2003) focused on one lower extremity injury in particular. • For the treatment of plantar fasciitis in elderly patients, they used a 4 degree medially wedged heel pad of low-density Plastazote® and a medium-density Plastazote orthosis under the medial longitudinal arch. • After a five week follow-up, all 10 patients showed a highly significant pain reduction (P≤.0001).

16. Plantar Fasciitis II • Kogler, Solomonidis, & Paul, (1996) cite that repeated loading of the foot and excessive tension of the plantar fascia have been implicated by several authors as a cause of plantar fasciitis, leading to heel pain and inflammation. • Logically, they believed that a medial arch support would dampen these effects, but they also desired to depict which type(s) of orthosis interventions would display the most efficacy.

17. Plantar Fasciitis II cont… • The experiment yielded significant results in relative strain percentage reduction in 3 of the 7 conditions. • These 3 orthoses differed in medial arch height, all being higher than the other conditions. In addition, 2, 3, and 5 had longer trimline delineations, in other words, the medial height of the orthosis extended further into the forefoot than the other two.

18. Plantar Fasciitis II cont… Effective inserts: #2, #3, and #5.

19. Good versus Bad Orthoses • Williams, Davis, and Baitch (2003) took 11 runners that had lower extremity pathologies that were not resolved with standard orthoses. • They were then fitted with and inverted graphite post (INV) with an medial angle of 15 or 25 degrees, depending on severity. • All runner’s returned to symptom-free running.

20. Replicate Study: Same Relief, Differing Biomechanics • Ferber, Davis, and Williams (2004) performed nearly the same exact study. • Main differences: • 11 healthy matched control subjects used. • There were no significant results in joint coupling differences between the control versus intervention groups. • There were not even significant differences in the intervention group when comparing INV to STD or INV to no orthoses conditions for any phase of stance! • The previous study mentioned by Williams, Davis, and Baitch (2003): • the INV condition presented a significantly decreased peak rearfoot inversion moment compared to the STD and no orthoses, measuring a 54% difference in 10 of the 11 runners. • The most unexpected outcome was a significant increase in TIR in the INV condition compared to the no orthoses condition

21. Orthoses for Standing Jobs ? • Kelaher, Mirka, and Dudziak (1997) have attempted to determine if orthoses should be recommended for asymptomatic individuals in the workplace. • 10 asymptomatic subjects (average age being 25.8) wore either flexible orthoses as the placebo or a semi-rigid orthoses for two months and switched treatments as part of the 18 week study. • There were no significant results for strength or postural stability. • The main result was a 12% decrease in back pain, but an equivalent 12% increase in foot discomfort.

22. Treatment as a Whole • Overall, most of the studies I reviewed found orthosis intervention to provide relief to those with various pathologies in the majority of cases, but not all. • Moraros and Hodge (1993) (as cited in Ball and Afheld, 2002) accounted that of 465 podiatric patients reporting various pathologies, 62% accredited complete resolution to orthosis treatment after 14 weeks of follow-up. • Likewise, of 347 long-distance runners, 76% reported a benefit from using orthoses (Gross, Davlin, & Evanski, 1991 (as cited in Ball and Afheld, 2002)). • Overall, at least 70% of runners will experience a reduction in symptoms with the use of orthoses as stated by Nigg et al (1999) and Nawoczenski et al (1995) (as cited in Ball and Afheld, 2002). This final statistic of 70% of the population experiencing relief concurs with what I have heard at the National Athletic Trainer’s Association Annual Symposium in 2005 during a “Runner’s Clinic” seminar.

23. Modern Research • While orthoses have been proven to be beneficial for many, the ideal designs for each condition has yet to be determined. • Joint coupling patterns remain elusive; the search continues. • Modern research has been gearing toward muscle work and compensations associated with orthoses as well as proprioceptive influences.

24. References • Ball, K. A., & Afheldt, M. J. (2002). Evolution of foot orthotics—part 1: coherent theory or • coherent practice? Journal of Manipulative Physiological Therapeutics, 25, 116-124. • Ball, K. A., & Afheldt, M. J. (2002). Evolution of foot orthotics—part 2: research reshapes long- • standing theory. Journal of Manipulative Physiological Therapeutics, 25, 125-134. • Deleo, A. T., Dierks, T. A., Ferber, R., Davis, I. S. (2004). Lower extremity joint coupling • during running: a current update. Clinical Biomechanics, 983-991. • Ferber, R., Davis, I. M., Williams III, D. S., (2005). Effect of foot orthotics on rearfoot and tibia • joint coupling patterns and variability. Journal of Biomechanics, 38, 477-483. • Fiolkowski, P., Brunt, D., Bishop, M., Woo, R., Horodyski, M. (2003). Intrinsic pedal • musculature support of the medial longitudinal arch: and electromyography study. The Journal of Ankle and Foot Surgery, 42, 327-333. • Hertel, J., Sloss, B., Earl, J. (2002). Effect of foot orthotics on quadriceps and gluteus medius • electromyographic activity during selected exercises presented in part to the National Athletic Trainers’ Association, Dallas, TX. • Imhauser, C., Abidi, N., Siegler, S., Frankel, D., Gavin, K., (2001). Biomechanical Evaluation • of the Efficacy of External Stabilizers in the Conservative Treatment of Acquired Flatfoot • Deformity, Part II presented at the American Orthopaedic Foot and Ankle Society, • Philadelphia, PA. • Kelaher, D. Mirka, G. A., Dudziak, K. Q. (2000). Effects of semi-rigid arch support orthotics: an • investigation with potential ergonomic implications. Applied Ergonomics, 31, 515-522. • Kogler, G. F., Solomonidis, S. E., Paul, J. P. (1996). Biomechanics of longitudinal arch support • mechanisms in foot orthoses and their effect on plantar aponeurosis strain. Clinical Biomechanics, 11, 243-252. • Kuhn, D. R., Shibley, N. J., Austin, W. M., Yochum, T. R. (1998). Radiographic evaluation of • weight-bearing orthotics and their effect on flexible pes planus. Journal of Manipulative Physiological Therapeutics, 22, 221-226. • Larsen, K., Weidich, F., Leboeuf-Yde, C. (2002). Can custom-made biomechanic shoe orthoses • prevent problems in the back and lower extremities? A randomized, controlled • intervention trial of 146 military conscripts. Journal of Manipulative Physiological Therapy, 25, 326-331. • Mundermann, A., Wakeling, J. M., Nigg, B. M., Humble, N., Stefanyshyn, D. J. (2004). Foot • orthoses affect frequency components of muscle activity in the lower extremity. Gait and Posture. • Nester, C. J., Linden, M. L., Bowker, P. (2003). Effect of Inverted Orthoses on Lower-Extremity • Mechanics in Runners. Gait and Posture 17, 180-188. • Rome, K., & Brown, C. L. (2004). Randomized clinical trial into the impact of rigid foot • orthoses on balance parameters in excessively pronated feet. Clinical Rehabilitation, 18, 624-630. • Stackhouse, C. L., Davis, I. M., Hamill, J. (2004). Orthotic intervention in forefoot and rearfoot • strike running patterns. Clinical Biomechanics, 64-70. • Stacoff, A., Reinschmidt, B. M., Nigg, A. J., van den Bogert, A. L., Denoth, J., Stussi, E. (2000). • Effects of foot orthoses on skeletal motion during running. Clinical Biomechanics, 15, 54-64. • Seligman, D. A., & Dawson, D. R. (2003). Customized heel pads and soft orthotics to treat heel • pain and plantar fasciitis. Archives of Physical Medicine and Rehabilitation, 84, 1564-1567. • Stude, D., & Gullickson, J. (2001). The effectes of orthotic intervention and 9 holes of simulated • golf on gait in experienced golfers. Journal of Manipulative and Physiological • Therapeutics, 24, 279-287. • Tochigi, Y., Takahashi, K., Yamagata, M., Yoshinaga, K., Wada, Y., Moriya, H., et al. (2000). • Effect of Arch Supports for Ankle-Subtalar Joint Complex Instability: A Biomechanical Experimental Studypresented at the American Orthopaedic Foot and Ankle Society. • Yung-Hui, L., & Wei-Hsien, H. (2004). Effects of shoe inserts and heel height on foot pressure, • impact force, and perceived comfort during walking. Department of Industrial Management, National Taiwan University of Science and Technology, 43.