A physeal injury in the distal femur in the neonate is rare. In general, traumatic neonatal physeal fracture usually occurs in the distal humerus and rarely occurs in the distal femur. The condition usually occurs due to birth trauma and usually results due to physeal separation which results in epiphyseal separation. The thigh will be swollen and there may be hypomobility of the extremity. The neonate will be fussy or irritated with significant swelling in the thigh. The condition is under diagnosed. The epiphysis is usually present at birth on x-rays. This condition can become complicated if the epiphysis is not completely ossified at birth or if the child is born prematurely. In this situation, the x-ray interpretation may be difficult. An MRI will be really helpful if the doctor is uncertain of the diagnosis. X-rays should be taken at the child at birth. The physician should look at the lateral x-ray and find the epiphysis is present and ossified at birth with varying degrees (may not be clear). Each epiphysis will line up with its corresponding bone. Epiphysis of the distal femur should line up with the femoral 
shaft. Epiphysis of the proximal tibia should line up with the tibial shaft. If the two epiphysis separate from each other, then this is a congenital dislocation of the knee. This can be a spectrum of injury that varies from hyperextension to subluxation, to frank dislocation. If the epiphysis is separated from its corresponding bone, for example, the epiphysis of the distal femur is separated from the shaft of the femur, then this is a physeal injury. Because the distal femur is mostly cartilaginous, you don’t see bone shifting, you see a little hint of the separation of the physis by seeing that the small ossified epiphysis is not in its normal position that corresponds with the axis of the bone. You need to know the difference between physeal injury and congenital dislocation of the knee. Accurate, gentle closed reduction with follow-up x-rays to confirm the reduction and to detect any early bony bridging.
Spontaneous Osteonecrosis of the Knee typically occurs in females older than 55. Usually one joint and one compartment is affected (medial femoral compartment). No etiology is known. Symptoms typically consist of a sudden onset of severe pain with decreased range of motion as well as swelling in the knee. X-rays will probably appear to be normal. An MRI is helpful, the provider may find a crescent shaped lesion. This condition
can cause arthritis. If severe knee pain is present in a middle aged or elderly female patient, and the x-ray is negative, the provider should order an MRI to rule out osteonecrosis of the knee. Treatment consists of protected weightbearing as well as therapy and NSAIDs. An arthroplasty may be required when conservative treatment fails. A unicompartmental knee arthroplasty will be performed for small lesions. A total knee arthroplasty will be completed for large lesions or collapse.
women after a knee arthroplasty. Secondary Osteonecrosis of the knee is common in women under 55 years of age and has associated risk factors. This condition involves more than one compartment or the metaphysis of the knee. Secondary Osteonecrosis occurs bilaterally in 80% of cases and multifocal lesions may be seen. There is a cause for Secondary Osteonecrosis of the knee, which is why it can be bilateral, multiple, and everywhere. Risk factors include:
Extension type fractures are the most common type, occurring approximately 95% of the time. Extension fractures typically occur due to falling onto an outstretched hand. With extension fractures, the distal fragment of the humerus displaces posteriorly. Anterior interosseous neurapraxia is the most common nerve palsy
occurring with supracondylar fractures. Injury to the anterior interosseous nerve will lead to weakness of the flexor digitorum profundus muscle to the index finger and the flexor pollicis longus muscle. The patient will not be able to make an “OK” sign or bend the tip of his index finger. Radial nerve neurapraxia is the second most common palsy and is evident by weakness in wrist and finger extension.
directly on a flexed elbow. In flexion type fractures, the distal fragment is displaced anteriorly. This type of fracture may be accompanied with ulnar nerve neurapraxia. Injury to the ulnar nerve will lead to a loss of sensation along the little finger. Later on, the patient may also have weakness of the intrinsic hand muscles and clawing.
The Gartland Classification System provides physicians with a way to categorize supracondylar humerus fractures. There are four classifications and are as follows: Type I fractures are nondisplaced fractures; Type II are angulated with an intact posterior cortex; Type III are completely displaced; and Type IV has complete periosteal disruption with instability in both flexion and extension.
lateral view x-ray should increase your suspicion of an occult fracture around the elbow. On a lateral view x-ray, the anterior humeral line is drawn along the anterior border of the distal humerus. Normally, the anterior humeral line should run through the middle third of the capitellum. In extension type fractures, the capitellum will be displaced posteriorly, relative to the anterior humeral line.
Treatment
Operative treatment is usually indicated for Types II and III, and are usually treated by a closed reduction and percutaneous pinning. During reduction, pronation of the forearm during elbow flexion helps to correct a varus deformity. After reduction, the surgeon will want to check for a gap in the fracture, as the neurovascular bundle may be trapped there. The surgeon will need to free the brachialis muscle from the fracture site if it is interpositioned there. Fixation is usually achieved with 2-3 
divergent lateral pins, depending on stability. Medial pins may also be added depending on stability; however, the surgeon will need to be aware of the ulnar nerve when placing the medial pin.
deformity can be corrected later on by a supracondylar valgus osteotomy. Vascular problems, such as compartment syndrome, may also occur. Volkmann’s ischemic contracture may occur due to a compression of the brachial artery with then patient is placed in a cast with the arm in hyperflexion (more than 90°).
The risk for medical uses is controversial and usually played down by physicians. Radiation at a high level is carcinogenic but, the level of radiation from x-ray exposure is low. The effects of low level radiation is not known.
It is known that CT scans, fluoroscopy, mammography, and x-rays expose the public to high levels of radiation, especially in young females. The risk of exposure should balance the medical benefits.
A CT scan of the pelvis has the highest level of exposure to the skin, marrow, and gonads. A mini fluoroscopy C-arm should be used whenever possible. Fluoroscopy emits a lot of radiation. The closer the extremity is to the radiation source, the higher the dose of radiation the patient receives. When the distance from the beam increases, the dose of radiation is less. Attempt to decrease exposure time. Radiation intensity follows the inverse square law. It is all about distance!
Units of Radiation
Methods of protection include: monitoring, shielding, and position. A dosimeter badge records how much radiation you have received; however, it does NOT protect you from exposure to radiation. Lead gowns and aprons work to stop exposure to fluoroscopic radiation. Lead aprons attenuate scattered radiation by about 95%. Rapidly dividing cells are most sensitive to radiation exposure and include: sperm, lymphocytes, and cells inside the small intestine and stomach.
Patient education is important. The patient should ask if the study is necessary and what is the lowest dose possible that can be given without compromising the study. Additionally, there should be a universal x-ray bank where patient’s x-rays can be accessed by any medical facility. This would eliminate the unnecessary repeating of x-rays.
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