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Magnetic Resonance Imaging (MRI) produces a 3-dimensional image that allows for exceptional evaluation of soft tissue structures, as well as the detection of boney change and the presence of excessive fluid accumulation associated with inflammation. Like CT, an MRI image may be viewed in various planes of orientation, improving visualization of anatomic structures and any associated pathologic change. MRI is considered the gold standard for diagnosing soft tissue injury within the foot. While it can provide a definitive diagnosis in cases where other imaging modalities have failed, it does have several limitations. Available magnet size restricts imaging to the level of the stifle or elbow, or below. MRI takes a significant amount of time acquire an image, which translates to long anesthesia times and therefore reduces the size of the area that may be imaged in a single session. The area thought to be associated with lameness must be placed in the MRI. MRI is therefore inappropriate for any lameness that can not be localized to a specific region of the limb. Additionally, MRI has limited availability and high cost compared to the other imaging modalities.
Horses may undergo standing MRI, where the horse is sedated and imaged with a low-field magnet (0.27 Tesla), or it may be placed in a high-field magnet (1.5 or 3 Tesla) while under general anesthesia. Low-field magnets produce less resolution and the subtle swaying of the standing horse leads to motion artifact (blurring of the image), especially in the case of the knee or hock, leading to reduced image quality. However, standing MRI tends to be cheaper, and it eliminates the risks of general anesthesia, such as further damage to the injured area or additional injury that may occur during anesthetic recovery.
Computed tomography (CT) is an imaging modality that produces a 3-dimensional radiograph. A series of plain radiographs are taken in a spiral around the site of interest, and the individual 2-D radiographs are converted into a 3-D image by a computer. The image may be manipulated to view in different planes, such as cross-section, making it possible to see an injury from multiple perspectives and improving diagnostic capabilities when compared to plain radiographs. Like plain radiographs, CT is not as useful for soft tissue lesions when compared to boney lesions. However, CT requires general anesthesia, and is more costly and less available than plain radiographs, limiting its use in general practice. CT provides a large amount of data with exceptional speed, taking only seconds to minutes to complete. When compared to MRI, it is not only significantly faster (MRI takes 1–2 hours to produce an image), but also less expensive. Its combination of speed and imaging capabilities makes it beneficial for use prior to orthopedic surgery, especially in the case of complicated fractures, as it allows for visualization from all sides so that the surgeon may determine the best approach and method of correction prior to cutting. Upon completion of the CT, the horse may be rolled straight into the surgery suite for immediate surgical treatment.
Diagnosis is made on the basis of history and a high index of suspicion. On examination there is tenderness to palpation on navicular head. Radiographs reveal typical changes of increased density and narrowing of the navicular bone
Putting the foot into proper neurological and biomechanical balance is crucial. Often navicular horses have long toes and underrun heels with very little inner wall depth or strength. Exposing the horse to proper stimulus to improve hoof form and structure is also vital.
The issue of hoof care is a subject of great debate. Corrective shoeing can be beneficial to horses suffering from navicular disease, although sometimes the effects are only temporary. Others believe that removing the shoes altogether is the best way to manage this disease, as it allows increased circulation to the hoof. People on both sides agree that proper hoof shape and angle are an important long-term management plan for a horse with navicular disease. As with laminitis, different horses may respond in different ways to a given technique, so the farrier, owner, and veterinarian should work as a team to formulate a plan and to adapt if the initial plan is not effective.
People who choose to treat navicular disease through shoeing may use a shoe designed to lift and support the heels. This can sometimes be accomplished with a flat shoe and trimming alone. Wedge pads or wedged shoes are often used, but can amplify heel-related problems if present. Another strategy is to use a bar type shoe. Often, an egg-bar shoe, or straight bar shoe. Some horses benefit from shoes that change the breakover of their foot (like a rolled toe). With or without shoes, the hoof must be trimmed in such a way as to restore the balance and angle that may have been lost. Horses with long toe-low heel conformation need careful trimming to counter this. Horses with upright feet may need their heels lowered and a shoe that will allow their heels to spread. Early intervention is key; in one study, shoeing was successful in 97% of horses treated within ten months of the onset of signs, while only 54% of horses lame for over a year responded.
Advocates of barefoot trimming cite recent studies which show that removing the shoes can help alleviate the symptoms of navicular disease, and in some cases, reverse some of the damage done to the hoof. Because navicular disease can be caused, or at least exacerbated by shoeing, removing the cause is the first step in this strategy toward the management of pain in the animal. Successive carefully applied trims help to restore the natural angle and shape of the hoof, while walking helps to stimulate circulation to the hoof. It is not uncommon to find horses whose navicular disease is completely manageable through corrective barefoot trimming. However, this may require a transition period lasting from weeks to years where the horse may remain lame, or may never become sound.
If there is significant degeneration in the bone, a flexor cortex cyst, adhesions to the deep digital flexor tendon, or avulsion fractures, relief is typically incomplete no matter what foot care technique is used.
Diagnosis is made on plain radiograph of the foot, although the extent of injury is often underestimated.
Treatment comprises early reduction of the dislocation, and frequently involves open reduction internal fixation to restore and stabilise the talonavicular joint. Open reduction and fusion of the calcaneocuboid joint is occasionally required.
In a case of an adolescent with rear foot pain, the physical exam will reveal that the foot movement is limited. This is both because there is a physical blockade to movement and because the brain will 'turn on' the muscles around the area to stop the joint moving toward the painful 'zone'. X-rays will usually be ordered and, in general, if there is enough toughness to the tissue bridge that pain has begun – there will usually be enough bone laid down to show up in an x-ray.
More high-tech investigations such as CT scan will be required if proceeding to surgery. If the bridge appears to be mostly fibrous tissue, an MRI would be the preferred modality to use.
With prompt treatment, particularly open reduction, and early mobilisation the outcome is generally good. High energy injuries and associated fractures worsen the outcome.
X-rays usually do not show evidence of new stress fractures, but can be used 3 weeks after onset of pain when the bone begins to remodel. A CT scan, MRI, or 3-phase bone scan may be more effective for early diagnosis.
MRI appears to be the most accurate test.
Aside from surgery, there are a few options for handling an accessory navicular bone that has become symptomatic. This includes immobilization, icing, medicating, physical therapy, and orthotic devices. Immobilizing involves placing the foot and ankle in a cast or removable walking boot. This alleviates stressors on the foot and can decrease inflammation. Icing will help reduce swelling and inflammation. Medication involves usage of nonsteroidal anti-inflammatory drugs, or steroids (taken orally or injected) to decrease inflammation. Physical therapy can be prescribed in order to strengthen the muscles and help decrease inflammation. Physical therapy can also help prevent the symptoms from returning. Orthotic devices (arch support devices that fit in a shoe) can help prevent future symptoms. Occasionally, the orthotic device will dig into the edge of the accessory navicular and cause discomfort. For this reason, the orthotic devices made for the patient should be carefully constructed.
In a high energy injury to the midfoot, such as a fall from a height or a motor vehicle accident, the diagnosis of a Lisfranc injury should, in theory at least, pose less of a challenge. There will be deformity of the midfoot and X-ray abnormalities should be obvious. Further, the nature of the injury will create heightened clinical suspicion and there may even be disruption of the overlying skin and compromise of the blood supply. Typical X-ray findings would include a gap between the base of the first and second toes. The diagnosis becomes more challenging in the case of low energy incidents, such as might occur with a twisting injury on the racquetball court, or when an American Football lineman is forced back upon a foot that is already in a fully plantar flexed position. Then, there may only be complaint of inability to bear weight and some mild swelling of the forefoot or midfoot. Bruising of the arch has been described as diagnostic in these circumstances but may well be absent. Typically, conventional radiography of the foot is utilized with standard non-weight bearing views, supplemented by weight bearing views which may demonstrate widening of the interval between the first and second toes, if the initial views fail to show abnormality. Unfortunately, radiographs in such circumstances have a sensitivity of 50% when non-weight bearing and 85% when weight bearing, meaning that they will appear normal in 15% of cases where a Lisfranc injury actually exists. In the case of apparently normal x-rays, if clinical suspicion remains, advanced imaging such as magnetic resonance imaging (MRI) or X-ray computed tomography (CT) is a logical next step.
Treatment usually involves resting the affected foot, taking pain relievers and trying to avoid putting pressure on the foot. In acute cases, the patient is often fitted with a cast that stops below the knee. The cast is usually worn for 6 to 8 weeks. After the cast is taken off, some patients are prescribed arch support for about 6 months. Also, moderate exercise is often beneficial, and physical therapy may help as well.
Prognosis for children with this disease is very good. It may persist for some time, but most cases are resolved within two years of the initial diagnosis. Although in most cases no permanent damage is done, some will have lasting damage to the foot. Also, later in life, Kohler's disease can spread to the hips.
The goal of non-surgical treatment of tarsal coalition is to relieve the symptoms by reducing the movement of the affected joint. This might include non-steroidal anti-inflammatory drugs (NSAIDs), steroidal anti-inflammatory injection, stabilizing orthotics or immobilization via a leg cast. At times, short term immobilization followed by long term orthotic use may be sufficient to keep the area free of pain.
Surgery is very commonly required. The type and complexity of the surgery will depend on the location of the coalition. Essentially, there are two types of surgery. Wherever possible, the bar will be removed to restore normal motion between the two bones. If this is not possible, it may be necessary to fuse the affected joints together by using screws to connect them solidly. Cutting away the coalition is more likely to succeed the younger the patient. With age comes extra wear in the affected and adjacent joints that makes treatment more difficult.
Most flexible flat feet are asymptomatic, and do not cause pain. In these cases, there is usually no cause for concern. Flat feet were formerly a physical-health reason for service-rejection in many militaries. However, three military studies on asymptomatic adults (see section below), suggest that persons with asymptomatic flat feet are at least as tolerant of foot stress as the population with various grades of arch. Asymptomatic flat feet are no longer a service disqualification in the U.S. military.
In a study performed to analyze the activation of the tibialis posterior muscle in adults with pes planus, it was noted that the tendon of this muscle may be dysfunctional and lead to disabling weightbearing symptoms associated with acquired flat foot deformity. The results of the study indicated that while barefoot, subjects activated additional lower-leg muscles to complete an exercise that resisted foot adduction. However, when the same subjects performed the exercise while wearing arch supporting orthotics and shoes, the tibialis posterior was selectively activated. Such discoveries suggest that the use of shoes with properly fitting, arch-supporting orthics will enhance selective activation of the tibialis posterior muscle thus, acting as an adequate treatment for the undesirable symptoms of pes planus.
Rigid flatfoot, a condition where the sole of the foot is rigidly flat even when a person is not standing, often indicates a significant problem in the bones of the affected feet, and can cause pain in about a quarter of those affected. Other flatfoot-related conditions, such as various forms of tarsal coalition (two or more bones in the midfoot or hindfoot abnormally joined) or an accessory navicular (extra bone on the inner side of the foot) should be treated promptly, usually by the very early teen years, before a child's bone structure firms up permanently as a young adult. Both tarsal coalition and an accessory navicular can be confirmed by X-ray. Rheumatoid arthritis can destroy tendons in the foot (or both feet) which can cause this condition, and untreated can result in deformity and early onset of osteoarthritis of the joint. Such a condition can cause severe pain and considerably reduced ability to walk, even with orthoses. Ankle fusion is usually recommended.
Treatment of flat feet may also be appropriate if there is associated foot or lower leg pain, or if the condition affects the knees or the lower back. Treatment may include using orthoses such as an arch support, foot gymnastics or other exercises as recommended by a podiatrist/orthotist or physical therapist. In cases of severe flat feet, orthoses should be used through a gradual process to lessen discomfort. Over several weeks, slightly more material is added to the orthosis to raise the arch. These small changes allow the foot structure to adjust gradually, as well as giving the patient time to acclimatise to the sensation of wearing orthoses. Once prescribed, orthoses are generally worn for the rest of the patient's life. In some cases, surgery can provide lasting relief, and even create an arch where none existed before; it should be considered a last resort, as it is usually very time consuming and costly.
Altering the biomechanics of training and training schedules may reduce the prevalence of stress fractures. Orthotic insoles have been found to decrease the rate of stress fractures in military recruits, but it is unclear whether this can be extrapolated to the general population or athletes. On the other hand, some athletes have argued that cushioning in shoes actually causes more stress by reducing the body's natural shock-absorbing action, thus increasing the frequency of running injuries. During exercise that applies more stress to the bones, it may help to increase daily calcium (2,000mg) and vitamin D (800 IU) intake, depending on the individual.
The Geist classification divides the accessory navicular bones into three types.
- Type 1: An os tibiale externum is a 2–3 mm sesamoid bone in the distal posterior tibialis tendon. Usually asymptomatic.
- Type 2: Triangular or heart-shaped ossicle measuring up to 12 mm, which represents a secondary ossification center connected to the navicular tuberosity by a 1–2 mm layer of fibrocartilage or hyaline cartilage. Portions of the posterior tibialis tendon sometimes insert onto the accessory ossicle, which can cause dysfunction, and therefore, symptoms.
- Type 3: A cornuate navicular bone represents an enlarged navicular tuberosity, which may represent a fused Type 2 accessory bone. Occasionally symptomatic due to bunion formation.
Studies have shown children and adolescents with flat feet are a common occurrence. The human arch develops in infancy and early childhood as part of normal muscle, tendon, ligament and bone growth . Flat arches in children usually become high arches as the child progresses through adolescence and into adulthood. Since children are unlikely to suspect or identify flat feet on their own, it is important for adult caregivers to check on this themselves. Besides visual inspection, caregivers should notice when a child's gait is abnormal. Children who complain about calf muscle pains, arch pain, or any other pains around the foot area may be developing or have developed flat feet. Children with flat feet are at a higher risk of developing knee, hip, and back pain. A recent randomized controlled trial found no evidence for the efficacy of treatment of flat feet in children either from expensive prescribed orthotics i.e (shoe inserts) or less expensive over-the-counter orthotics. As a symptom itself, flat feet usually accompany genetic musculoskeletal conditions such as dyspraxia, ligamentous laxity or hypermobility.
Options include operative or non-operative treatment. If the dislocation is less than 2 mm, the fracture can be managed with casting for six weeks. The patient's injured limb cannot bear weight during this period. For severe Lisfranc injuries, open reduction with internal fixation (ORIF) and temporary screw or Kirschner wire (K-wire) fixation is the treatment of choice. The foot cannot be allowed to bear weight for a minimum of six weeks. Partial weight-bearing may then begin, with full weight bearing after an additional several weeks, depending on the specific injury. K-wires are typically removed after six weeks, before weight bearing, while screws are often removed after 12 weeks.
When a Lisfranc injury is characterized by significant displacement of the tarsometatarsal joint(s), nonoperative treatment often leads to severe loss of function and long-term disability secondary to chronic pain and sometimes to a planovalgus deformity. In cases with severe pain, loss of function, or progressive deformity that has failed to respond to nonoperative treatment, mid-tarsal and tarsometatarsal arthrodesis (operative fusion of the bones) may be indicated.
Type II should be managed conservatively whereas type I and Ia requires to be treated surgically. Surgery involves four major steps:
- Development of the calcaneal part of the foot
- Repositioning of the navicular bone
- New adjustment of the ankle, and
- Various stabilization measures including the Grice operation and transposition of various tendons.
The term osteochondrosis has been used to describe a wide range of lesions among different species. There are different types of the prognosis: latens, which is a lesion restricted to epiphyseal cartilage, manifesta, a lesion paired with a delay in endochondral ossification, and dissecans which is a cleft formation in the articular cartilage.
The prognosis for these conditions is very variable, and depends both on the anatomic site and on the time at which it is detected. In some cases of osteochondrosis, such as Sever's disease and Freiberg's infraction, the involved bone may heal in a relatively normal shape and leave the patient asymptomatic. On the contrary, Legg-Calvé-Perthes disease frequently results in a deformed femoral head that leads to arthritis and the need for joint replacement.
In humans, these conditions may be classified into three groups:
1. Spinal: Scheuermann's disease (of the interspinal joints) which is a curve in the thoracic spine.
2. Articular: Legg-Calvé-Perthes disease (or, avascular necrosis of the femoral head in the hip), Köhler's disease (of the tarsal navicular bone of the foot), Panner's disease (of the capitulum of the elbow), and Freiberg's infraction (of the second or third metatarsal of the foot and less frequently the first or fourth; sometimes called Freiberg's Infraction or Freiberg's disease)
3. Non-articular: This group includes Sever's disease (of the calcaneus, or heel), and Kienbock's disease of the hand, and other conditions not completely characteristic of the osteochondrosis, such as Osgood-Schlatter's disease (of the tibial tubercle) and Osteochondritis dissecans.
Rocker bottom foot, also known as congenital vertical talus, is an anomaly of the foot. It is characterized by a prominent calcaneus (heel bone) and a convex rounded bottom of the foot. It gets its name from the foot's resemblance to the bottom of a rocking chair.
It can be associated with Edwards' syndrome (trisomy 18), Patau syndrome (trisomy 13), Trisomy 9 and mutation in the gene HOXD10.
It can also be associated with Charcots foot.
The first clinical manifestation of Paget's disease is usually an elevated alkaline phosphatase in the blood.
Paget's disease may be diagnosed using one or more of the following tests:
- Pagetic bone has a characteristic appearance on X-rays. A skeletal survey is therefore indicated.
- An elevated level of alkaline phosphatase in the blood in combination with normal calcium, phosphate, and aminotransferase levels in an elderly patient are suggestive of Paget's disease.
- Markers of bone turnover in urine "eg". Pyridinoline
- Elevated levels of serum and urinary hydroxyproline are also found.
- Bone scans are useful in determining the extent and activity of the condition. If a bone scan suggests Paget's disease, the affected bone(s) should be X-rayed to confirm the diagnosis.
Although initially diagnosed by a primary care physician, endocrinologists (internal medicine physicians who specialize in hormonal and metabolic disorders), rheumatologists (internal medicine physicians who specialize in joint and muscle disorders), orthopedic surgeons, neurosurgeons, neurologists, oral and maxillofacial surgeons, podiatrists, and otolaryngologists are generally knowledgeable about treating Paget's disease, and may be called upon to evaluate specialized symptoms. It can sometimes difficult to predict whether a person with Paget's disease, who otherwise has no signs or symptoms of the disorder, will develop symptoms or complications (such as a bone fracture) in the future.
Diagnosis of Dercum's disease is done through a physical examination. In order to properly diagnose the patient, the doctor must first exclude all other possible differential diagnosis. The basic criteria for Dercum's disease are patients with chronic pain in the adipose tissue (body fat) and patients who are also obese. Although rare, the diagnosis may not include obesity. Dercum's disease can also be inherited and a family medical history may aid in the diagnosis of this disease. There are no specific laboratory test for this disease. Ultrasound and magnetic resonance imaging can play a role in diagnosis.