Heel Wedge Research Articles

Wedge and Eggbar Shoes Change the Pressure Distribution Under the Hoof of the Forelimb in the Square Standing Horse

Summary The shoe types most commonly applied to horses with navicular disease or other forms of palmar heel pain are shoes with heel wedges and eggbar shoes, although their efficacy has been a matter of debate among veterinarians and farriers for centuries. To quantify the effect of these different types of “navicular” shoeing on static hoof pressure distribution, 6 warmblood horses were shod with 6° wedge, eggbar, and plain shoes. While standing square with weight evenly distributed across both forelimbs, the center of pressure and pressures at selected areas of interest (AOI: toe, medial and lateral toe, medial and lateral heel) were measured using a Footscan (RsScan International, Belgium) pressure plate in a Latin square design using the plain shoe as a reference. Wedge shoes did not provide a significant shift in the center of pressure. The application of eggbar shoes did not alter the relative position of the center of pressure under the hoof. However, the absolute distance from the toe to the center of pressure was significantly larger with eggbar shoes (77 + 12 mm) compared with plain and wedged shoes (70 ± 8 mm, P < .05) resulting in an absolute, caudal shift of the center of pressure. When pressure (N/cm 2) values at the five AOIs were averaged for each shoe type, the wedge and eggbar shoe recordings showed a significantly lower mean pressure than plain shoes ( P < .05). In conclusion, mean AOI pressures decreased with wedge and eggbar shoes, and eggbar shoes provided a caudal shift in the center of pressure. These effects are believed to decrease the moment of the coffin joint and reduce the pressure on the navicular bone. Thus, the findings of this study might contribute to the scientific evidence of efficacy of the use of wedge and eggbar shoes in “navicular” lame horses.

Static and dynamic biomechanics of foot orthoses in people with medial compartment knee osteoarthritis

Objective. Gait biomechanics (knee adduction moment, center of pressure) and static alignment were investigated to determine the mechanical effect of foot orthoses in people with medial compartment knee osteoarthritis. Design. Repeated measures design in which subjects were exposed to three conditions (normal footwear, heel wedge and orthosis) in random order. Background. The knee adduction moment is an indirect measure of medial compartment loading. It was hypothesized that the use of a 5° valgus wedge and 5° valgus modified orthosis would shift the center of pressure laterally during walking, thereby decreasing the adduction moment arm and the adduction moment. Methods. Peak knee adduction moment and center of pressure excursion were obtained in nine subjects with medial compartment knee OA during level walking using an optoelectric system and force plate. Static radiographs were taken in 12 subjects using precision radiographs. Results. There was no difference between conditions in static alignment, the peak adduction moment or excursion of the center of pressure in the medial-lateral direction. No relationship was found between the adduction moment and center of pressure excursion in the medial-lateral plane. The displacement of the center of pressure in the anterior–posterior direction, measured relative to the laboratory coordinate system, was decreased with the orthosis compared to the control condition ( P=0.036) and this measure was correlated with the adduction moment ( r=0.45, P=0.019). Conclusions. The proposed mechanism was not supported by the findings. The reduction in the center of pressure excursion in the anterior–posterior direction suggests that foot positioning was altered, possibly to a toe-out position, while subjects wore the orthoses. Based on the current findings, we hypothesize that toe-out positioning may reduce medial joint load. Relevance Knee Osteoarthritis is the most common cause of chronic disability amongst seniors. Developing inexpensive, non-invasive treatment strategies for this large population has potential to impact health care costs, quality of life and clinical outcomes.

Calculated forelimb flexor tendon forces in horses with experimentally induced superficial digital flexor tendinitis and the effects of application of heel wedges.

To calculate forces in the flexor tendons and the influence of heel wedges in affected and contralateral (compensating) forelimbs of horses with experimentally induced unilateral tendinitis of the superficial digital flexor (SDF) tendon. 5 Warmblood horses. Procedure-Ground reaction force and kinematic data were obtained during a previous study while horses were trotting before and after induction of tendinitis in 1 forelimb SDF and after application of 6 degrees heel wedges to both forehooves. Forces in the SDF, deep digital flexor (DDF), and the suspensory ligament (SL) and strain in the accessory ligament (AL) of the DDF were calculated, using an in vitro model of the distal region of the forelimb. After induction of tendinitis, trotting speed slowed, and forces decreased in most tendons. In the affected limb, SL force decreased more than SDF and DDF forces. In the compensating limb, SDF force increased, and the other forces decreased. After application of heel wedges, SDF force in both limbs increased but not significantly. Furthermore, there was a decrease in DDF force and AL strain. The increase in SDF force in the compensating forelimb of horses with unilateral SDF tendinitis may explain the high secondary injury rate in this tendon. The lack of decrease of SDF force in either limb after application of heel wedges suggests that heel wedges are not beneficial in horses with SDF tendinitis. Instead, heel wedges may exacerbate the existing lesion.

Orthopaedics: Effects of ‘navicular’ shoeing on equine distal forelimb kinematics on different track surface

Summary Orthopaedic shoeing applied for disorders such as navicular disease is mostly evaluated on hard track surfaces, but very often horses are ridden only on soft tracks. To compare the effects of normal shoes, eggbar shoes, and shoes with heel wedges (5 degrees) on the kinematics of the distal forelimb on hard and soft track surfaces, eleven sound Dutch Warmblood horses were led across three different tracks (an asphalt, a fibre/sand mix (= Agterberg), and a pure sand track) with three different shoe types (a normal shoe, an eggbar shoe, and a shoe with heel wedges). The hoof rotation and the maximal extension of the fetlock joint at midstance period were recorded by an infrared‐light based gait analysis system (ProReflexe®) at walk and at trot. Statistical analysis revealed significant effects of track and shoe type, and a shoe‐track interaction (p<0.05). On soft track surfaces, the equilibrium of the distal forelimb dictated a 1.5–4 degrees forward rotation of the normal or eggbar shod foot, the most on a sand track. The wedge effect on hoof rotation, however, was always significantly greater, but similar to that on the hard track surface (5 degrees forward rotation). The maximal fetlock extension was less on a soft surface, in particular on the sand track (p<0.05). This decrease was most pronounced when the horses were shod with heel wedges and was least pronounced with normal shoes. In conclusion, in particular the sand track allows a forward rotation of the hoof and thus relief of pressure in the navicular area, and a decrease in maximal fetlock extension and thus unloading of the fetlock joint. The extra forward rotation of the hoof induced by heel wedges on hard tracks was almost the same on soft track surfaces. Eggbars and fibre/sand mix tracks have intermediate effects on unloading of the distal forelimb.

Effect of rearfoot orthotics on postural sway after lateral ankle sprain

Hertel J, Denegar CR, Buckley WE, Sharkey NA, Stokes WL. Effect of rearfoot orthotics on postural sway after lateral ankle sprain. Arch Phys Med Rehabil 2001;82:1000-3. Objective: To investigate the effects of different rearfoot orthotics on postural sway during unilateral stance after lateral ankle sprain. Design: Repeated-measures 3-factor analysis of variance on postural sway length and velocity in the frontal and sagittal planes with factors being stance leg (injured, uninjured), session (within 3d, 2wk, 4wk postinjury), and condition (6 orthotic conditions). Setting: University biomechanics laboratory. Patients: Fifteen collegiate athletes with acute, unilateral first- or second-degree lateral ankle sprain. Interventions: Balance testing was performed under 6 conditions: (1) shoe only, (2) molded Aquaplast orthotic, (3) lateral heel wedge, (4) 7° medially posted orthotic, (5) 4° laterally posted orthotic, and (6) neutral orthotic. Main Outcome Measures: Postural sway length and postural sway velocity in the frontal and sagittal planes. Results: Significant main effects were found for side and session, but not orthotic condition, for all 4 dependent variables. Postural sway length and velocity were greater on the injured limbs as compared with the uninjured limbs during the first 2 sessions but not during the third session. None of the orthotics significantly reduced postural sway compared with the shoe-only condition after lateral ankle sprain. Conclusions: Rearfoot orthotics, irrespective of design or posting, were ineffective at improving postural sway after lateral ankle sprain. © 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Three-dimensional kinematics of the proximal interphalangeal joint: effects of raising the heels or the toe.

The proximal interphalangeal joint (PIPJ) has always been considered as a low-motion joint with an almost constant angle during loading of the limb. Until very recently, its motion was not taken into account in kinematic studies in vivo. Recent in vivo studies yielded surprisingly high ranges of motion in this joint. The aim of this study was to measure, in terms of the 3 possible rotations (flexion/extension, collateromotion and axial rotation), the movements of the PIPJ in vitro during limb loading in a neutral position (500-6000 N) and after the addition of heel and toe wedges (6 degrees and 12 degrees). The joint coordinate system, as it was recently described for use in the horse, was used to compute the 3 components of rotation. With the hoof in neutral position, low-amplitude flexion movements (7.9 degrees) were observed. They were not associated with collateromotion or axial rotation. The flexion of the joint increased exponentially with load suggesting that, during the midstance phase, heavy loads are necessary to evoke substantial flexion. Raising the heels induced an early flexion of the joint with an increase of its total amplitude. Raising the toe produced an extension at 500 N, beyond which the amount of flexion was reduced. These results show that PIPJ flexion/extension during in vitro loading remains substantially smaller than suggested by in vivo studies based on skin markers. Raising the toe or heel directly affects the behaviour of this joint, but does not induce motion outside the sagittal plane. Hoof wedges are commonly used in clinical practice for purposes other than affecting PIPJ motion. In these cases, their biomechanical effects on this joint should be taken into account.

Effects of a Heel Wedge in Horses with Superficial Digital Flexor Tendinitis

SummaryThe objective was to determine whether the use of heel wedges is an appropriate treatment for superficial digital flexor (SDF) tendinitis. The subjects were six warmblood horses in which SDF tendinitis was induced in one forelimb using a collagenase model. The stride characteristics were compared under four conditions: flat shoes; 6° heel wedge following a one hour adaptation; 6° heel wedge following five days adaptation; and one hour after reapplication of flat shoes. Videographic and force data were collected for both forelimbs during the stance phase of the trot, and were combined with morphometric measurements using an inverse dynamics method to calculate net joint moments and joint powers at each of the joints of the forelimbs. Repeated measures ANOVA was used to compare the stride variables across conditions in the lame limb and in the compensating forelimb. Significant kinematic changes in response to the use of heel wedges were confined to the coffin joint which was more flexed due to the more upright orientation of the hoof segment. The onset of breakover was delayed with the hoof wedges. In the compensating limb only, the use of heel wedges was associated with a shift of the net joint moment to the dorsal side of the coffin joint during the first one third of stance. Both forelimbs had significantly smaller peak palmar moments at the coffin joint with heel wedges in the second half of stance, which appeared to be a mechanical consequence of the more flexed position of the coffin joint. Tension was increased in the extensor branches of the suspensory ligament and common digital extensor tendon on the dorsal side, and reduced in the deep digital flexor tendon and its distal accessory ligament on the palmar side. Less energy was absorbed across the coffin joint in both limbs with heel wedges. The study did not reveal changes associated with the use of heel wedges that could be interpreted as a reduction of the effects of lameness due to SDF tendinitis.The objective was to determine whether the application of 60 heel wedges was appropriate for treating horses with superficial digital flexor (SDF) tendinitis. The significant effects of the heel wedges affected the coffin joint and included a more flexed position due to the more upright orientation of the hoof segment, a reduction in the peak palmar moment and less energy absorption across the joint. Since these changes were confined to the coffin joint, they were not interpreted as being beneficial in treating lameness due to SDF tendinitis.

The effect of orthopaedic shoeing on the force exerted by the deep digital flexor tendon on the navicular bone in horses.

This study quantifies both the intended effect of orthopaedic shoeing to decrease the load on the navicular bone and the eventual undesired effects on gait performance. The compressive force exerted by the deep digital flexor tendon on the navicular bone and on the quality of the trot and redistribution of forces over the flexor tendons and the suspensory ligament were studied as a function of orthopaedic shoeing in 12 sound Dutch Warmblood horses. A modified CODA-3 gait analysis system and a force plate were used to quantify objectively the load on the lower limb. The quality of the trot was assessed using the same gait analysis system while the horses were trotting on the treadmill. The effects of shoes with heel wedges and egg-bar shoes were compared to flat shoes and unshod feet. When heel wedges were applied, the maximal force on the navicular bone was reduced by 24% (P<0.05) in comparison with flat shoes. Egg-bar shoes did not reduce the force on the navicular bone, but in unshod feet this force appeared to be 14% lower (P<0.05) compared to flat shoes. Egg-bar shoes cause the horse's trot to be slightly less animated (P<0.05), compared to flat shoes and shoes with heel wedges. It is concluded that shoes with heel wedges reduce the force on the navicular bone as a result of a decreased moment of force at the distal interphalangeal joint in combination with a decreased angle between the deep digital flexor tendon distally and proximally of the navicular bone. Therefore it can be expected that in horses suffering from navicular disease, heel wedges will have the expected beneficial effect on the pressure on the navicular bone, while the effect of egg-bar shoes remains doubtful.

The rehabilitative management of the traumatic brain injury patient with associated femoral neuropathy

The initial diagnoses of associated injuries in patients with traumatic brain injury (TBI) are often overlooked because of the priority given to life-sustaining measures. Pelvic and abdominal injuries comprise less than 5% each of the concurrent injuries associated with TBI and multiple trauma. This report describes a 32-year-old man who sustained a moderate TBI with facial, pelvic, and extremity fractures secondary to a fall. His hospital course was complicated by sepsis, acute renal failure, and retroperitoneal hemorrhage. Admitted to the rehabilitation service 6 weeks after the fall, the patient was found to have a previously undiagnosed profound quadriceps muscle weakness. A diagnosis of femoral neuropathy was confirmed by electrodiagnostic studies and was attributed to compression by pelvic hematomas. Rehabilitation management included use of a solid ankle cushion heel (SACH) wedge, a functional knee brace, a progressive ambulation program, neuromuscular stimulation, and patient and family education with an emphasis on safety. The patient progressed rapidly with his rehabilitation program, improving from moderate assistance in all skills to independence in 3 weeks. This case illustrates the importance of the physiatrist's role in the early detection of associated injuries in patients with multiple trauma and TBI; it also illustrates some of the rehabilitation techniques that may be employed to aid a patient with a femoral neuropathy to regain junctional ability.

Application of a Lateral Heel Wedge as a Nonsurgical Treatment for Varum Gonarthrosis

Application of a Lateral Heel Wedge as a Nonsurgical Treatment for Varum Gonarthrosis

A method for measuring foot pressures using a high resolution, computerized insole sensor: the effect of heel wedges on plantar pressure distribution and center of force.

A new, high resolution, pressure-sensitive insole was tested and found to provide reproducible measurements of static and dynamic plantar pressures inside the shoe of normal test subjects under certain conditions. However, calibration between separate sensors was poor and the sensor pads showed significant wear with use. This system was also used to investigate the effect of heel wedges on plantar foot pressure to determine whether this system was sensitive enough to detect the effect of a gross shoe modification on plantar foot pressure. Medial heel wedges decreased plantar pressures under the first and second metatarsals as well as under the first toe, and shifted the center of force laterally in all portions of the foot. Lateral heel wedges decreased pressures under the third, fourth, and fifth metatarsals, increased pressures under the first and second metatarsals, and shifted the center of force medially in all portions of the foot. Our evaluations indicate that it is possible to measure static and dynamic plantar foot pressures within shoes and to study the possible effect of shoe modifications on plantar pressures in controlled gait trials.

Treatment of osteoarthritis of the knee with heel wedges

Sixty-two patients with early medial compartment osteoarthritis of the knee were treated with lateral heel wedges and followed for from 7 years and 5 months to 12 years. Those who were treated with heel wedges and analgesics showed a significantly greater improvement in pain score than those treated with analgesics only, but not in the walking ability score at the second follow up. The lateral heel wedge had no effect on the progress of the radiographic changes. The lateral heel wedge is useful for patients with early medical compartment osteoarthritis provided it is used with an understanding of the indications and its limitations.

Tarsal Tunnel Syndrome

In 14 patients tarsal tunnel syndrome was associated with varus heels and pronated, splayed forefeet. Review of the literature and the author's experience suggest that these conditions may be a common cause of the tarsal tunnel syndrome. Treatment of fixed varus deformities of the heel by outer heel wedges has been shown to be ineffective. Although outer heel wedges provide symptomatic relief in patients with relatively flexible hindfeet, surgical release of the flexor retinaculum behind the medial malleolus is the treatment of choice in patients who have the tarsal tunnel syndrome with planovarus deformity and is successful in more than 90% of cases. The tarsal tunnel syndrome, in the author's experience, is grossly underdiagnosed. Tarsal tunnel syndrome should be suspected in patients who have pain in the bottom of the feet without localized forefoot tenderness, who have a varus heel and a pronated, splayed forefoot, and who have a positive Tinel's sign behind the medial malleolus. It is important to differentiate tarsal tunnel syndrome from a peripheral neuropathy that obviously will not respond to surgical intervention.

The Anterior Heel for Metatarsalgia in the Adult Foot

A conservative approach to foot problems is especially useful in patients with diabetes, rheumatoid arthritis, diminished circulatory changes, and those who are too debilitated for surgical treatment. If one will start with either the medial heel wedge or the anterior heel correction, some response should be evident within 4 to 6 weeks. If the response after a trial period of approximately two to three months for a heel wedge or another two to three months for the anterior heel doesn't relieve pain, then perhaps some other problem might now become easier to localize, i.e. Morton's toe syndrome, hallux valgus, soft or hard corns, or hammertoe deformities. When the anterior heel is prescribed many foot problems other than metatarsalgia will stop being symptomatic and surgery treatment can be bypassed. A physician must know about the supply of shoes in the community and, if necessary, instigate a better inventory of available shoes. In addition, it is necessary to establish good rapport with the shoe repair man so that he will not intrude in your patient rapport or alter your directions. Patients also need advice about losing weight. Frequently a loss of 15 or 20 pounds will change a patient's complaint from one of extremely discomforting daily weight-bearing to a tolerance of a fair amount of walking and at least a reduction of the complaints to a more endurable and functional level. One can't expect the shoe correction to do everything for everyone. The anterior heel isn't the whole solution to the complicated problem but it helps to have patients begin to see results in more comfort in their shoe wear.

PROGRESS IN ORTHOPEDIC SURGERY FOR 1945 A Review Prepared by an Editorial Board of the American Academy of Orthopaedic Surgeons

Static Strain on the Feet. —Pemberton 112 reports on the care of soldiers' feet. He says that mild strain on the feet manifested only by pain in the feet and legs on walking, plus tenderness, requires no treatment except proper fitting of shoes and foot hygiene. The commonest condition is faulty posture of the feet, resulting in one of the several types of flatfoot. Treatment is directed at correction of the pronation. Mild conditions are treated with a 3/16 inch (0.48 cm.) inner heel wedge. A firm flexible arch support is used in severer conditions, with the high point under the sustentaculum tali. Steel arch supports have no place in the Army. The flexible support is made of shoe leather with properly fitted felt pads. For a congenital weak foot, flexible arch supports and taping are advised. Congenital flatfoot is not disabling and probably no more subject to strain than