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.

Thermography, or thermal imaging, measures the heat gradient of skin by detection of infrared radiation. Because heat is a cardinal sign of inflammation, thermal imaging can be used to detect inflammation that may be the cause of lameness, and at times discover a subclinical injury. When used, horses must be placed in an area free of sunlight exposure, drafts, or other sources of outside heat, and hair length should be uniform in the area imaged. Benefits include non-invasiveness and the potential for early identification of injury, and detection of early contralateral limb injury in the case of orthopedic patients.

The classic diagnostic technique is with appropriate X-rays and hip scoring tests. These should be done at an appropriate age, and perhaps repeated at adulthood - if done too young they will not show anything. Since the condition is to a large degree inherited, the hip scores of parents should be professionally checked before buying a pup, and the hip scores of dogs should be checked before relying upon them for breeding. Despite the fact that the condition is inherited, it can occasionally arise even to animals with impeccably hip scored parents.

In diagnosing suspected dysplasia, the x-ray to evaluate the internal state of the joints is usually combined with a study of the animal and how it moves, to confirm whether its quality of life is being affected. Evidence of lameness or abnormal hip or spine use, difficulty or reduced movement when running or navigating steps, are all evidence of a problem. Both aspects have to be taken into account since there can be serious pain with little X-ray evidence.

It is also common to X-ray the spine and legs, as well as the hips, where dysplasia is suspected, since soft tissues can be affected by the extra strain of a dysplastic hip, or there may be other undetected factors such as neurological issues (e.g. nerve damage) involved.

There are several standardized systems for categorising dysplasia, set out by respective reputable bodies (Orthopedic Foundation for Animals/OFA, PennHIP, British Veterinary Association/BVA). Some of these tests require manipulation of the hip joint into standard positions, in order to reveal their condition on an X-ray.

The following conditions can give symptoms very similar to hip dysplasia, and should be ruled out during diagnosis:

- Cauda equina syndrome (i.e. lower back problems)

- Cranial (anterior) cruciate ligament tears

- Other rear limb arthritic conditions

- Osteochondritis dissecans and elbow dysplasia in the forelimbs are difficult to diagnose as the animal may only exhibit an unusual gait, and may be masked by, or misdiagnosed as, hip dysplasia.

A dog may misuse its rear legs, or adapt its gait, to compensate for pain in the "forelimbs", notably osteoarthritis, osteochondritis (OCD) or shoulder or elbow dysplasia, as well as pain in the hocks and stifles or spinal issues. It is important to rule out other joint and bodily issues before concluding that only hip dysplasia is present. Even if some hip dysplasia is present, it is possible for other conditions to co-exist or be masked by it.

Physical examination often begins with examination of the patient's gait. In OCD of the knee, people may walk with the involved leg externally rotated in an attempt to avoid tibial spine impingement on the lateral aspect of the medial condyle of the femur.

Next, the examining physician may check for weakness of the quadriceps. This examination may reveal fluid in the joint, tenderness, and crepitus. The Wilson test is also useful in locating OCD lesions of the femoral condyle. The test is performed by slowly extending the knee from 90 degrees, maintaining internal rotation. Pain at 30 degrees of flexion and relief with tibial external rotation is indicative of OCD.

Physical examination of a patient with ankle OCD often returns symptoms of joint effusion, crepitus, and diffuse or localized tenderness. Examination often reveals symptoms of generalized joint pain, swelling, and times with limited range of motion. Some with loose body lesions may report catching, locking, or both. The possibility of microtrauma emphasizes a need for evaluation of biomechanical forces at the knee in a physical examination. As a result, the alignment and rotation of all major joints in the affected extremity is common, as are extrinsic and intrinsic abnormalities concerning the affected joint, including laxity.

X-rays show lucency of the ossification front in juveniles. In older people, the lesion typically appears as an area of osteosclerotic bone with a radiolucent line between the osteochondral defect and the epiphysis. The visibility of the lesion depends on its location and on the amount of knee flexion used. Harding described the lateral X-ray as a method to identify the site of an OCD lesion.

Magnetic resonance imaging (MRI) is useful for staging OCD lesions, evaluating the integrity of the joint surface, and distinguishing normal variants of bone formation from OCD by showing bone and cartilage edema in the area of the irregularity. MRI provides information regarding features of the articular cartilage and bone under the cartilage, including edema, fractures, fluid interfaces, articular surface integrity, and fragment displacement. A low T1 and high T2 signal at the fragment interface is seen in active lesions. This indicates an unstable lesion or recent microfractures. While MRI and arthroscopy have a close correlation, X-ray films tend to be less inductive of similar MRI results.

Computed tomography (CT) scans and Technetium-99m bone scans are also sometimes used to monitor the progress of treatment. Unlike plain radiographs (X-rays), CT scans and MRI scans can show the exact location and extent of the lesion. Technetium bone scans can detect regional blood flow and the amount of osseous uptake. Both of these seem to be closely correlated to the potential for healing in the fragment.

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.

Diagnosis is through x-rays, arthroscopy or CT (computed tomography). In cases with significant lameness, surgery is the best option, especially with UAP. However, conservative treatment is often enough for cases of FMCP and OCD of the medial humeral epicondyle. The dogs are exercised regularly and given pain medication, and between the ages of 12 to 18 months the lameness will often improve or disappear. Control of body weight is important in all cases of elbow dysplasia, and prevention of quick growth spurts in puppies may help to prevent the disease.

Surgery for FMCP consists of removal of cartilage and bone fragments and correction of any incongruity of the joint. Reattachment of UAP with a screw is usually attempted before the age of 24 weeks, and after that age the typical treatment is removal of the UAP. Without surgery, UAP rapidly progresses to osteoarthritis, but with FMCP osteoarthritis typically occurs with or without surgery. Osteoarthritis is also a common sequela of OCD of the humerus despite medical or surgical treatment. Elbow replacement surgery has been developed and can be an option for treatment

Initial diagnosis often is made during routine physical examination. Such diagnosis can be confirmed by a medical professional such as a neurologist, orthopedic surgeon or neurosurgeon. A person with foot drop will have difficulty walking on his or her heels because he will be unable to lift the front of the foot (balls and toes) off the ground. Therefore, a simple test of asking the patient to dorsiflex may determine diagnosis of the problem. This is measured on a 0-5 scale that observes mobility. The lowest point, 0, will determine complete paralysis and the highest point, 5, will determine complete mobility.

There are other tests that may help determine the underlying etiology for this diagnosis. Such tests may include MRI, MRN, or EMG to assess the surrounding areas of damaged nerves and the damaged nerves themselves, respectively. The nerve that communicates to the muscles that lift the foot is the peroneal nerve. This nerve innervates the anterior muscles of the leg that are used during dorsi flexion of the ankle. The muscles that are used in plantar flexion are innervated by the tibial nerve and often develop tightness in the presence of foot drop. The muscles that keep the ankle from supination (as from an ankle sprain) are also innervated by the peroneal nerve, and it is not uncommon to find weakness in this area as well. Paraesthesia in the lower leg, particularly on the top of the foot and ankle, also can accompany foot drop, although it is not in all instances.

A common yoga kneeling exercise, the Varjrasana has, under the name "yoga foot drop," been linked to foot drop.

Conservative therapies include NSAIDs, pain medication, weight management and exercise restriction. The problems with these therapies is that they do not work well, especially long-term.

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.

Presence at birth is extremely rare and associated with other congenital anomalies such as proximal femoral focal deficiency, fibular hemimelia or anomalies in other part of the body such as cleidocranial dyastosis. The femoral deformity is present in the subtrochantric area where the bone is bent. The cortices are thickened and may be associated with overlying skin dimples. External rotation of the femur with valgus deformity of knee may be noted. This condition does not resolve and requires surgical management. Surgical management includes valgus osteotomy to improve hip biomechanics and length and rotational osteotomy to correct retroversion and lengthening.

In order to qualify a patient's condition as BSS, the bending angle must be greater than 45 degrees. While the presence of the condition is very easy to note, the cause of the condition is much more difficult to discern. Conditions not considered to be BSS include vertebral fractures, previously existing conditions, and ankylosing spondylitis. Lower-back CT scans and MRIs can typically be used to visualize the cause of the disease. Further identification of the cause can be done by histochemical or cellular analysis of muscle biopsy.

Camptocormia is becoming progressively found in patients with Parkinson's disease.

The diagnosis of Parkinson's-associated camptocormia includes the use of imaging of the brain and the spinal cord, along with electromyography or muscle biopsies.

Muscle biopsies are also a useful tool to diagnose camptocormia. Muscle biopsies found to have variable muscle fiber sizes and even endomysial fibrosis may be markers of bent spine syndrome. In addition, disorganized internal architecture and little necrosis or regeneration is a marker of camptocormia.

Patients with camptocormia present with reduced strength and stooped posture when standing due to weakened paraspinous muscles (muscles parallel to the spine). Clinically, limb muscles show fatigue with repetitive movements. Paraspinous muscles undergo fat infiltration. Electromyography may be used as well in diagnosis. On average, the paraspinous muscles of affected individuals were found to be 75% myopathic, while limb muscles were 50% percent myopathic. Creatine kinase activity levels in skeletal muscle are a diagnostic indicator that can be identifiable through blood tests.

More common cause: primary defect in endochondral ossification of the medial part of the femoral neck.

Excessive interuterine pressure on the developing fetal hip.

vascular insult.

Faulty maturation of the cartilage and metaphyseal bone of the femoral neck.

Clinical feature: presents after the child has started walking but before six years of age. Usually associated with a painless hip due to mild abductor weakness and mild limb length discrepancy.

If there is a bilateral involvement the child might have a waddling gait or trendelenburg gait with an increased lumbar lordosis. The greater trochanter is usually prominent on palpation and is more proximal. Restricted abduction and internal rotation.

X-ray: decreased neck shaft angle, increased cervicofemoral angle, vertical physis, shortened femoral neck decrease in femoral anteversion. HE angle (hilgenriener epiphyseal angle- angle subtended between a horizontal line connecting the triradiate cartilage and the epiphysisn normal angle is <30 degrees.

Treatment:

HE angle of 45–60 degrees observation and periodic follow up.

Indication for surgery :HE angle more than 60 degrees, progressive deformity, neckshaft angle <90 degrees, development of trendelenburg gait

Surgery: subtrochantric valgus osteotomy with adequate internal rotation of distal fragment to correct anteversion

common complication is recurrence. If HE angle is reduced to 38 degrees less evidence of recurrence

post operative spica cast is used for a period of 6–8 weeks.

Coxa vara is also seen in Niemann–Pick disease.

Trendelenburg's sign is found in people with weak or paralyzed abductor muscles of the hip, namely gluteus medius and gluteus minimus. It is named after the German surgeon Friedrich Trendelenburg.

The gluteus medius is very important during the stance phase of the gait cycle to maintain both hips at the same level. Moreover, one leg stance accounts for about 60% of the gait cycle. Furthermore, during the stance phase of the gait cycle, there is approximately three times the body weight transmitted to the hip joint. The hip abductors' action accounts for two thirds of that body weight. The Trendelenburg sign is said to be positive if, when standing on one leg, the pelvis drops on the side opposite to the stance leg to reduce the load by decreasing the lever arm. By reducing the lever arm, this decreases the work load on the hip abductors. The muscle weakness is present on the side of the stance leg. A Trendelenburg sign can occur when there is presence of a muscular dysfunction (weakness of the gluteus medius or minimus) or when someone is experiencing pain. The body is not able to maintain the center of gravity on the side of the stance leg. Normally, the body shifts the weight to the stance leg, allowing the shift of the center of gravity and consequently stabilizing or balancing the body. However, in this scenario, when the patient/person lifts the opposing leg, the shift is not created and the patient/person cannot maintain balance leading to instability.

The Trendelenburg gait pattern (or gluteus medius lurch) is an abnormal gait (as with walking) caused by weakness of the abductor muscles of the lower limb, gluteus medius and gluteus minimus. People with a lesion of superior gluteal nerve have weakness of abducting the thigh at the hip.

This type of gait may also be seen in L5 radiculopathy and after poliomyelitis, but is then usually seen in combination with foot drop.

During the stance phase, the weakened abductor muscles allow the pelvis to tilt down on the opposite side. To compensate, the trunk lurches to the weakened side to attempt to maintain a level pelvis throughout the gait cycle. The pelvis sags on the opposite side of the lesioned superior gluteal nerve.

This gait is precipitated by strain to the gluteus maximus and gluteus minimus. Sufferers frequently complain that an overly strenuous session at the gym, particularly with glute-isolating equipment, result in this awkward gait, or worse.

This gait may be caused by cleidocranial dysostosis.

Biofeedback and physical therapy have been used in treatment.

When the hip abductor muscles (gluteus medius and minimus) are weak, the stabilizing effect of these muscles during gait is lost.

When standing on the right leg, if the left hip drops, it's a positive right Trendelenburg sign (the contralateral side drops because the ipsilateral hip abductors do not stabilize the pelvis to prevent the droop).

"When the patient walks, if he swings his body to the right to compensate for left hip drop, he will present with a compensated Trendelenburg gait; the patient exhibits an excessive lateral lean in which the thorax is thrust laterally to keep the center of gravity over the stance leg."

The underlying disorder must be treated. For example, if a spinal disc herniation in the low back is impinging on the nerve that goes to the leg and causing symptoms of foot drop, then the herniated disc should be treated. If the foot drop is the result of a peripheral nerve injury, a window for recovery of 18 months to 2 years is often advised. If it is apparent that no recovery of nerve function takes place, surgical intervention to repair or graft the nerve can be considered, although results from this type of intervention are mixed.

Non-surgical treatments for spinal stenosis include a suitable exercise program developed by a physical therapist, activity modification (avoiding activities that cause advanced symptoms of spinal stenosis), epidural injections, and anti-inflammatory medications like ibuprofen or aspirin. If necessary, a decompression surgery that is minimally destructive of normal structures may be used to treat spinal stenosis.

Non-surgical treatments for this condition are very similar to the non-surgical methods described above for spinal stenosis. Spinal fusion surgery may be required to treat this condition, with many patients improving their function and experiencing less pain.

Nearly half of all vertebral fractures occur without any significant back pain. If pain medication, progressive activity, or a brace or support does not help with the fracture, two minimally invasive procedures - vertebroplasty or kyphoplasty - may be options.

Ankles can be stabilized by lightweight orthoses, available in molded plastics as well as softer materials that use elastic properties to prevent foot drop. Additionally, shoes can be fitted with traditional spring-loaded braces to prevent foot drop while walking. Regular exercise is usually prescribed.

Functional electrical stimulation (FES) is a technique that uses electrical currents to activate nerves innervating extremities affected by paralysis resulting from spinal cord injury (SCI), head injury, stroke and other neurological disorders. FES is primarily used to restore function in people with disabilities. It is sometimes referred to as Neuromuscular electrical stimulation (NMES)

The latest treatments include stimulation of the peroneal nerve, which lifts the foot when you step. Many stroke and multiple sclerosis patients with foot drop have had success with it. Often, individuals with foot drop prefer to use a compensatory technique like steppage gait or hip hiking as opposed to a brace or splint.

Treatment for some can be as easy as an underside "L" shaped foot-up ankle support (ankle-foot orthoses). Another method uses a cuff placed around the patient's ankle, and a topside spring and hook installed under the shoelaces. The hook connects to the ankle cuff and lifts the shoe up when the patient walks.

Due to the wide range of causes of camptocormia, there is no one treatment that suits all patients. In addition, there is no specific pharmacological treatment for primary BSS. The use of analgesic drugs depends entirely on the intensity of the back pain. Muscular-origin BSS can be alleviated by positive lifestyle changes, including physical activity, walking with a cane, a nutritious diet, and weight loss. Worsening of symptoms is possible but rare in occurrence.

Treatment of the underlying cause of the disease can alleviate the condition in some individuals with secondary BSS. Other treatment options include drugs, injections of botulinum toxin, electroconvulsive therapy, deep brain stimulation, and surgical correction. Unfortunately, many of the elderly individuals affected by the BSS are not treated surgically due to age-related physical ailments and the long postoperative recovery period.

An antalgic gait is a gait that develops as a way to avoid pain while walking ("" = "" + "", "against pain"). It is a form of gait abnormality where the stance phase of gait is abnormally shortened relative to the swing phase. It can be a good indication of pain with weight-bearing.

The person's feet seem attached to the floor as if by a magnet. In magnetic gait, each step is initiated in a "wresting" motion carrying feet upward and forward. Magnetic gait can be visualized in terms of a powerful magnet being forcefully pulled from a

steel plate.

Steppage gait (High stepping, Neuropathic gait) is a form of gait abnormality characterised by foot drop due to loss of dorsiflexion. The foot hangs with the toes pointing down, causing the toes to scrape the ground while walking, requiring someone to lift the leg higher than normal when walking.

It can be caused by damage to the deep peroneal nerve.

Exact diagnosis remains widely built on precise history taking, with the characteristic clinical and radiographic skeletal features. Genetic diagnosis is based on DNA sequencing. Because plasma COMP levels are significantly reduced in patients with COMP mutations, such as pseudoachondroplasia, measuring plasma COMP levels has become a reliable means of diagnosing this and pathopysiologically similar disorders.

Accurate assessment of plain radiographic findings remains an important contributor to diagnosis of pseudoachondroplasia. It is noteworthy that vertebral radiographic abnormalities tend to resolve over time. Epiphyseal abnormalities tend to run a progressive course. Patients usually suffer early-onset arthritis of hips and knees. Many unique skeletal radiographic abnormalities of patients with pseudoachondroplasia have been reported in the literature.

- Together with rhizomelic limb shortening, the presence of epiphyseal-metaphyseal changes of the long bones is a distinctive radiologic feature of pseudoachondroplasia.

- Hypoplastic capital femoral epiphyses, broad short femoral necks, coxa vara, horizontality of acetabular roof and delayed eruption of secondary ossification center of os pubis and greater trochanter.

- Dysplastic/hypoplastic epiphyses especially of shoulders and around the knees.

- Metaphyseal broadening, irregularity and metaphyseal line of ossification. These abnormalities that are typically encountered in proximal humerus and around the knees are collectively known as “rachitic-like changes”.

- Radiographic lesions of the appendicular skeleton are typically bilateral and symmetric.

- Oval shaped vertebrae with anterior beak originating and platyspondyly demonstrated on lateral radiographs of the spine.

- Normal widening of the interpedicular distances caudally demonstrated on anteroposterior radiographs of the dorsolumbar region. This is an important differentiating feature between pseudoachondroplasia and achondroplasia.

- Odontoid hypoplasia may occur resulting in cervical instability.

Gluteal gait is an abnormal gait caused by neurological problems. If the superior gluteal nerve or obturator nerves are injured, they fail to control the gluteus minimus and medius muscles properly, thus producing an inability to tilt the pelvis upward while swinging the leg forward to walk. To compensate for this loss, the leg swings out laterally so that the foot can move forward, producing a shuffling or waddling gait.

Injury to the superior gluteal nerve results in a characteristic motor loss, resulting in a disabling gluteus medius limp, to compensate for weakened abduction of the thigh by the gluteus medius and minimus, and/or a gluteal gait, a compensatory list of the body to the weakened gluteal side.

As a result of this compensation, the center of gravity is placed over the supporting lower limb. Medial rotation of the thigh is also severely impaired. When a person is asked to stand on one leg, the gluteus medius and minimus normally contract as soon as the contralateral foot leaves the floor, preventing tipping of the pelvis to the unsupported side. When a person with paralysis of the superior gluteal nerve is asked to stand on one leg, the pelvis descends on the unsupported side, indicating that the gluteus medius on the contralateral side is weak or non-functional. This observation is referred to clinically as a positive Trendelenburg's sign.

When the pelvis descends on the unsupported side, the lower limb becomes, in effect, too long and does not clear the ground when the foot is brought forward in the swing phase of walking. To compensate, the individual leans away from the unsupported side, raising the pelvis to allow adequate room for the foot to clear the ground as it swings forward.

Myopathic gait (or waddling gait) is a form of gait abnormality.

The "waddling" is due to the weakness of the proximal muscles of the pelvic girdle.

The patient uses circumduction to compensate for gluteal weakness.

Conditions associated with a myopathic gait include pregnancy, congenital hip dysplasia, muscular dystrophies and spinal muscular atrophy