2Objectives Define Orthotics Discuss Common Orthotics Focus on Foot OrthoticsExplain importance of Subtalar JointReview biomechanics of the foot- normal and pathologicReview functional theories of foot orthoticsAssess foot orthotics role in the prevention and treatment of injury
3What is an Orthotic??Definition: An orthopedic appliance/device designed to correct, straighten or support a body part
4How do they work?? Prevent abnormal motion or movement? Change mechanics?Proprioception?
16Types of Orthotics Prefabricated OTC Advantage Disadvantage Dr. Scholls, Spenco, HapadAdvantageCheapConvenientEffectiveDisadvantageMass producedNonspecific arch contourFails to address positional/structural deformities and compensations
17Types of Orthotics Biomechanical or Custom Advantage Disadvantage Address the source of compensationSlow rate/extent of deformityDisadvantageCostExperience of providerMay not help
18Accomodative Orthotics Fit in shoe to stabilize foot deformityAllows foot to compensateTransfer weight from painful areaImproves shock absorptionControl ground reactive forces around a specific locationExample: Diabetic foot, Neuropathy, PVD, congenital malformations
19Functional or Corrected Orthotic Addresses patho-mechanical components of the lower extremity/foot/ankle conditionResists abnormal compensationPrevent pain during ambulationPrevent pathologic ROMExample: athletes, pes planus, pes cavus
20Custom: Stiffness Rigid (pes planus) control foot function provide stabilityfirm materialSemi-rigid (athletes)dynamic balance of footlayers of soft/rigid laterialSoft (pes cavus)absorb shockimprove balanceremove pressurecompressible material
23Indications Support and correct intrinsic deformities Decrease frequency of lower limb injuriesControl ROMImprove sensory feedback / proprioception/neuromuscular responsesDissipate pathologic ground reaction forces and improve shock absorptionImprove LE biomechanics
24Evaluation Chief complaint Assess mobility (hypo, hyper) Type of orthotic needed (dress, athletic, street)RigidityMaterial
25Evaluation Assess ROM, positioning Test lower quadrant muscle strength Static stance position and toe riseLeg length measurementGait analysisAssess position & motion of spine hip/pelvis, knee, lesser metatarsals
26How are they made??CastingImpressionsGait/Balance Analysis
27Modifications Metatarsal (MT) head cut-out Heel cushioning MT cut-outModificationsMetatarsal (MT) head cut-outHeel cushioningMetatarsal padsMorton’s extensionRigid forefoot extensionMorton’s extensionPadHeel cushioning
28How are they made?? No matter which method is done….. Subtalar Joint must be in neutral position
30Subtalar Joint Oblique orientation Allows for pronation and supination Motion is tri-planarAffects motion/flexibility of midtarsal joint and tibiaControls plantar surface pressure and contact with the ground during gait
31SubTalar Joint Oblique axis: -23 degrees from long axis of foot horizontal plane
44Abnormal Pronation Add 6° eversion to calcaneal ROM (nl=20°) Increase ground reaction forces along medial chainExcess internal rotation of tibiaMuscles work harder to keep balanceDecrease stability during propulsion
45Abnormal Supination Add >12° of calcaneal inversion (nl=10°) Increased forces along lateral chainHypomobility in subtalar jointDecreased shock-absorbing capabilityDecreased stability at heel strike
46Subtalar Joint and Orthotics Position of STJ affects position and function of entire footNeutral STJ is the point in the stance phase of gait where joint is not compensated
47Subtalar Joint (STJ) and Orthotics If capture pronated/supinated (compensated) foot for molding orthotic, get contour that reflects and facilitates compensated positionWant orthotic to control STJ motion before it compensates to allow optimal function of joints/muscles
48Clinical significance??? Do abnormal properties of gait lead to clinical pathology??Do orthotics change biomechanics of gait??If so, have they been proven to prevent injuries??
49Messier SP, Pittala KA. MSSE: Oct 1988;20(5):501-5 Retrospective studyRelationship between biomechanical variables and injury (ITB, shin splints, plantar fasciitis)Results:-Nonsignificant increase inover-pronation and high arches in injury group
50Willems TM, et al. Gait & Posture 23 (2006):91-98 Prospective study in freshmen athletes in BelgiumRisk factors for exercise-related lower leg pain (ERLLP)Gait examined and injuries loggedResultsOverpronation associated with increased incidence of ERLLP
51Kaufman KR, Brodine SK, et al. Am J Sports Med. 1999;27(5):585-93 Prospective study on Navy SealsBiomechanics measured prior to training and injuries logged over 2 yearsResults:-Pes planus & cavus had 2X incidence of stress fracture compared to normal arch
52Simkin A., et al. Foot Ankle. 1989;10(1):25 Prospective study of military recruitsArches measured and incidence of stress fractures recordedFemoral/tibial stress fractures higher with high archesMetatarsal stress fractures higher in low arches
53Increased risk of Stress Fracture/Overuse injury with Pes Cavus Cowan, D., etal. MSSE 1989; 21: S60.McKenzie, D., et al. Sports Med. 1985;2: 334.Messier, S. P, et al. MSSE. 1988; 20: 501.Warren, B. L, et al. MSSE. 1987; 19: 71.Rodgers MM. Phys Ther. 1988; 68: 1822.Chan CW. Mayo Clin Proc. 1994; 69: 448.
54How do orthotics work??Foot orthoses are generally believed to align the skeleton and to reduce the loading of biological structures in the lower extremities…but is there evidence??
55Mundermann, Nigg, et al. Clin Biomech. 2003; 18: 254 Effects of posting and custom-molding of foot orthotics on lower extremity kinematicsResultsMolding reduced maximum tibia rotation, foot inversion, and foot inversion velocityMolding also reduced magnitude of vertical impact forceResults similar by adding medial post
56Eng JJ, Pierrynowski MR. Phys Ther. 1994;74:836. Effect of custom foot orthotics on subtalar joint and knee joint during walking and runningAdolescent females with PFPS and measured forefoot varus +/- calcaneal valgus >6°ResultsSubtalar joint rotation reduced 1 to 3 ° with orthoticsKnee motion reduced in frontal plane during walking, not running
57Nester CJ, et al. Gait Posture. 2003; 17: 180. Assess the effect of medially and laterally wedged foot orthotics on joint movementsHealthy subjectsResultsMedial wedgeDecreased rearfoot pronationIncreased lateral ground reaction forceLateral wedgeIncreased rearfoot pronationDecreased lateral ground reaction force
58MacLean C, et al. Clin Biomech. 2006 (in press). Evaluate influence of custom foot orthotics on kinematics in runnersHealthy runners (normal eversion angles)ResultsStatistically significant reduction in rearfoot eversion angle in initial stanceNo significant findings at knee joint
59Stacoff A., et al. Clin Biomech. 2000; 15: 54. Effects of medial foot orthotics on skeletal movements in runningHealthy male subjects (no overpronators)Results:-No change in eversion or tibial rotation with orthotics
60Ferber R, et al. J Biomech. 2005; 38: 477. Compare joint-coupling patterns (eversion/tibial internal rotation) with/without orthotics during running11 overpronators measuredResultsNo difference observed in treated group
61Can orthotics help prevent and/or treat injury????
62Rome K, et al. Cochrane Database Syst Rev. 2005; Issue 2. Evaluated evidence from 10 randomized controlled trials of interventions for prevention of stress fracturesAll trials involved military recruits and “shock-absorbing” insertsResults4 trials showed decrease in stress injuriesEvidence not consistent on particular designComfort very important
63Gross ML et al. Am J Sports Med. 1991;19:409. Questionnaire to runners wearing orthotics for various lower extremity complaintsPredominant insert type was flexibleResults75.5% found improvement in their condition since wearing orthotic90% continued to wear them after symptom resolution
64Johnston LB, Gross MT. J Orthop Sports Phys Ther. 2004;34:440. Effect of foot orthotics on quality of life in those with PFPS who demonstrate excessive pronation3 month intervention with orthoticsResultsSignificant decreases in pain/stiffness after only 2 weeks compared to pretreatment evaluation
65COLLINS, ETAL. BJM :a1735Compare PT, flat inserts or custom orthotics52 wks all similar improvement
66Others… James S., et al. Am J Sp Med. 1978; 6: 40. 78% with knee pain returned to running with orthotic use.D’Ambrosia, et al. Clin Sports Med. 1985; 4: 611Custom orthotics reduce frequency of running injuries.Donatelli R., et al. J Orthop. Sports Phys. Ther. 1988; 10: 205Survey showed 96% had pain relief from orthotics in treating tibial, knee, and ankle pain70% able to return to activity
67Take home points…Foot orthotics come in all shapes/sizes and are used for a variety of conditionsWhen writing prescriptions:-Know your foot type and activity level-Identify trouble spots (for pads, wedges, etc…)Subtalar joint is an important factor in understanding gait biomechanics and keeping in neutral controls compensation
68Take home points…Abnormal biomechanics are proven to increase risk for injuryStill debate over how orthotics actually workStill work to be done on effectiveness…but comfort is key!!!