Common Foot Conditions and Injections

 

Conditions which cause pain and inflammation are treatable with the use of diagnostic and therapeutic injections. The purpose of this article is to shed some light on common ankle and foot conditions that may require injections and where the proper sites to perform these injections are located.

anklejoint

Ankle Joint

The ankle joint is formed by articulation of the tibia and talus. Injections are performed here to alleviate pain occurring from trauma, arthritis, gout, or other ankleeeeinflammatory conditions. Anterolateral Ankle Impingement can occur due to the build-up of scar tissue in the ankle joint or from the presence of bony spurs. When executing an injection here, the ankle will need to be in a neutral position. The physician will mark the injection site just above the talus and medial to the tibialis anterior tendon. The injection site should be disinfected with betadine. Then, the needle is inserted into the identified site and directed posterolaterally. The solution is injected into the joint space and should flow smoothly without resistance. It may be helpful to pull on the foot in order to distract the ankle joint.

First Metatarsophalangeal Joint

The MTP joint is a common injection site frequently affected by gout and firstmetaosteoarthritis. The injection site is first disinfected with betadine and then the needle is inserted on the dorsomedial or dorsolateral surface. The needle is angled at 60-70° of the plane to match the slope of the joint. The solution is injected into the joint space and should flow smoothly without resistance. Pulling on the big toe is sometimes helpful in distracting the joint.

 

Peroneal Tendonitis

Peroneal Tendonitis is an irritation to the tendons that run on the outside area of the ankle, the peroneus longus and peroneus brevis. First, the injection site is disinfected with betadine. Then, the needle should be carefully inserted in a proximal direction when injecting the peroneus brevis and longus tendon sheath. The needle will need to advance distally to inject the peroneus brevis alone at its bony insertion.

peroneal

Achilles Tendonitis

Achilles Tendonitis is an irritation and inflammation of the large tendon in the back of the ankle. Achilles tendonitis is a common overuse injury that occurs in athletes. needlingInjections of steroids should be given around the tendon, not through the tendon. The injections inserted directly into the tendon is not recommended due to the increased risk of tendon rupture. A platelet injection can be done through the tendon with needling and fenestration.

 

Tarsal Tunnel Syndrome

Tarsal Tunnel Syndrome is a condition of pain and paresthesia caused by irritation to the posterior tibial nerve. When performing an injection for this condition, the tarsal tunnelphysician will want to feel the pulse of the posterior tibial artery. The nerve is posterior and the physician will want to find the area of maximum tenderness. The injection site should be 1-2cm above the tender area, which is marked on the medial side of the foot and disinfected with betadine. The solution is injected at a 30° angle and directed distally. It is important to inform the patient that the foot may become numb and that care should be taken when walking and driving. Injections for Tarsal Tunnel Syndrome are usually performed after a treatment program which can include rest stretching and the use of shoe inserts.

 

Plantar Fasciitis

The plantar fascia is a band of connective tissue deep to the fat pad on the plantar aspect of the foot. Patients with plantar fasciitis complain of chronic pain symptoms that are often worse in the morning with walking. The injection site is identified and marked on the medial side of the foot and betadine is used as a disinfectant. The physician will need to avoid injecting through the fat pad at the bottom of the foot to avoid fat atrophy. The needle is inserted in a medial to lateral direction one finger breath above the sole of the foot, in a line that corresponds to the posterior aspect of the tibia. The solution is injected past the midline of the width of the foot.plantar

 

Osteonecrosis of the Hip

Osteonecrosis or Avascular Necrosis of the hip is death of a segment of bone in the femoral head due to disruption of the blood supply. The etiology of this condition is not fully understood. There are several risk factors associated with osteonecrosis of the hip. The condition occurs bilaterally in about 80% of patients. It is important for the physician to check both hips, even if one is asymptomatic. An early diagnosis is important because during the early stages of osteonecrosis, a femoral head preserving procedure can be done. In the late stages of osteonecrosis, the femoral head collapses and cannot be saved. The femoral head may need to be replaced. Obtain AP and Frog Leg Lateral views of the hip. The Frog Leg Lateral view will show the crescent sign.

An MRI is the imaging of choice, especially when the patient has persistent hip pain, the radiographs are negative, and the diagnosis of osteonecrosis is suspected.

osteonoThe Ficat Classification is a commonly used system to stage osteonecrosis of the hip. Stage I classifications will have a normal appearing x-ray and an MRI will detect the lesion; changes in the marrow. Stage II classifications are identified by sclerosis and cyst formation. Characteristics of the Stage III classifications are a subchondral fracture and the appearance of a crescent sign and flattening of the femoral head. Stage IV classifications will show advanced lesions with arthritis, osteophyte formation, and a loss of the joint space.

stages

Treatment

For early stages of osteonecrosis of the hip, initial trial of nonsurgical treatment is usually done. Surgery may be needed if nonsurgical methods are not successful. Nonoperative treatment typically consists of bisphosphonates.

femoral head collapsedThese drugs may be used before the femoral head collapses and are still in the experimental stages. In regards to traditional surgical treatment, when the lesion is small a head preserving procedure can be done. For stages I & II, a core decompression is used. The surgeon can make a single large hole or multiple small holes in the femoral head. It decompresses the head and stimulates a healing response. The lesion is done anteriorly and superiorly.

bonegraft222If the surgeon chooses to perform a core decompression with bone graft, they will debride the necrotic area and insert the bone graft into the open space. Vascularized Fibular Grafts are done in younger patients. Complications include: donor site pain and leg dysfunction as well as tibial stress fractures on the side the graft was taken. Stages III and IV will require a total hip arthroplasty (cementless cup and stem) or total hip resurfacing; however, resurfacing is not commonly used. A total hip replacement is considered to be the traditional procedure for advanced stages of osteonecrosis of the hip. Total hip resurfacing is considered to be controversial because the patient will need adequate bone stock to support the femoral component. The result is not as good when compared with a patient with osteoarthritis.totalhip

 

Skin Warts

underwartsSkin warts are a solid blister or small rough growth that looks like cauliflower and is caused by a virus infection (HPV human papillomavirus). There are many types of warts. The most common types are harmless; though contagious. A person with a broken area of skin may be subject to contracting the virus. Skin warts can appear in multiples. They usually disappear after several months but, may last for years and reoccur. Some say that you get warts from touching frogs and toads. However, this is false. Skin warts come from human viruses and not frogs and toads.

faceThe most common warts occur on the hands; however, they can also occur on the face, genitals, or the soles of the feet. Verruca vulgaris is a raised wart with a roughened surface. It is a thickened skin tissue.foot

Treatment

Many topical products can be used and the best products will contain salicylic acid. Cryotherapy is also useful in removal. Silver nitrate can be used but it may pigment the fingerwartsskin. All of these treatments are aimed at removing the wart but, the wart may regrow after it has been removed. Warts are hard to treat and there is no cure.

Individuals should try to avoid touching patients with warts. Those affected by warts should not try to remove them from their face or genitals.

Data shows that half of the warts resolve in one year. 70% of warts may resolve in two years. Avoid any treatment that may produce scarring.

froggyyyy

 

Radiation Exposure and Safety

X-rays ionize human tissue and deposit energy that can cause harmful changes within the body (break the DNA chain). Additionally, there is a cancer risk from exposure to x-rays. The dose of radiation is cumulative. X-rays are considered carcinogenic. The government is attempting to minimize the use of unnecessary CT scans and x-rays to prevent unnecessary exposure to radiation. It is important for doctors to pay close attention to the risks involved with the use of x-rays. The cancer risk associated with radiation exposure is documented in cases of atomic bomb survivors.

radiationThe 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.

What is the safe radiation level?

The safe level of radiation is not known.

ctscanIt 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.

Optimize radiation doses by only exposing the patient to enough radiation to get a clear image. There is a growing concern about the risk associated with giving a patient large doses of radiation. The use of CT scans has increased recently in adults and children, possibly exposing the patient to an unnecessarily high dose of radiation. A CT scan is often the method used to diagnose cancer, diseases, and fractures, exposing the patient to a much larger dose of radiation than x-rays. Radiation from a CT scan of the pelvis equals the same amount as 100 chest x-rays. Children are ten times more sensitive to radiation than adults. 3-4 million children receive CT scans and about 1,500 of them will develop cancer two decades later. Additionally, children should not be given an adult dose of radiation.

Radiation Dose Limits

dose limitsA 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!

If the intensity of radiation at 1 meter from the source is 100mR/hr, then the intensity of radiation at 2 meters from the source is ¼ or 25mR/hr in the same unit area. At 3 meters from the source, the intensity of radiation is 1/9 the original or 11.1mR/hr.

inversion square lawUnits of Radiation

  • Roentgen
    • Unit of radiation exposure in the air
  • Rad
    • Energy absorbed per gram of tissue
  • Rem
    • Biological effect of a rad

There is less exposure to the physician when imaging a smaller body part. Larger body parts create an increased exposure to the physician when imaging a patient with the C-arm. It is important to not be in the direct path of the radiation beam.

less expoMethods 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.

Radiation damage seldom appears at the time or irradiation. The first effects of radiation damage is usually seen as a drop in the white blood cell count. The first external sign of damage is usually a skin burn. Studies suggest that people who use fluoroscopy extensively have a higher rate of cataracts.

Early effects of radiation exposure include:

  • Death
  • Hematologic depression
  • Chromosome aberration
  • Skin erythema
  • Epilation

My recommendations:

A CT scan examination is usually done without justification by most insurances. In my opinion, 1/3 of CT scan studies that are given could be avoided; they are an added cancer risk with no benefit. The CT scan study should be justified. There is no close oversight or uniform standard in place to eliminate radiation exposure, and this is something that should be taken seriously.

shieldPatient 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.

In summary, the bone marrow, breast tissue, gonads, and lymphatic tissue are susceptible to radiation induced tumors. It is important to shield the gonads from exposure. Always wear protective equipment such as lead aprons and monitor your radiation exposure with the dosimeter badge.