Dr. Evalynn Vasquez, MD, MBA

Kidney stones can be smooth or jagged and are yellow to brown in color. They are mostly comprised of the minerals calcium, oxalate, and phosphorus. Examining the stones to see what they are made of can show what caused the stone to be formed in the first place. For example, a stone made of mostly calcium, which is the most common type, can happen any time the urine becomes too concentrated due to dehydration or a blockage in the kidney. A uric acid stone forms when acid levels in the urine get too high, usually due to excessive consumption of animal protein such as meat and fish. A struvite stone is a sign of certain infections, and a cystine stone can be due to a genetic disorder that raises the risk of kidney stones.

The most common symptom of kidney stones is pain, either in the back or lower abdomen, or severe pain when urinating. There may also be blood in the urine. Treatment for kidney stones depends on how large the stone is. Very small stones can pass out of the body on their own, and they do not require treatment other than drinking adequate water and taking pain killers. Larger stones need to be broken apart and removed. The main treatment options are:

• Shock wave lithotripsy, which uses sound wave vibrations to break apart the stone
• Percutaneous nephrolithotomy, or the use of a very tiny tool (like a wire inserted through the back) to break apart and remove the stone
• Ureteroscopy, a thin tube inserted through the urethra and bladder to the stone, where tiny tools can grasp the stone and remove

People who have had one kidney stone are at risk of developing another. To reduce this risk, patients are given instructions specific to the type of stone they developed. Generally the instructions will include drinking more water to dilute the urine, but it may also involve lowering sodium intake or eating less meat.

Spinal cord injury medicine seeks to stabilize the spine and to alleviate the symptoms of spine damage. Practitioners of spinal cord injury medicine are called spinal cord injury specialists. Spinal cord injury medicine is an interdisciplinary field, meaning physicians of various specialties may be trained to treat spinal cord injuries.

Damage to the spinal cord may initially be diagnosed through X-ray, MRI, or CT scans. Patients can also undergo spinal exams to evaluate their sensory ability and strength. Injuries to the spinal cord can be complete (no feeling or sensation) or incomplete (some feeling or sensation remains). Conditions spinal cord injury medicine specialists may treat include:

• Paralysis, such as paraplegia (loss of function in the legs), or quadriplegia (loss of function from the neck down)
• Spine fracture or trauma, which can lead to impairment and/or significant pain
• Spinal infections
• Myelopathies, such as herniated disks, spinal tumors, and rheumatoid arthritis
• Inflammatory diseases such as ankylosing spondylosis, and degenerative conditions like Lou Gehrig's disease (ALS)

Treatment for spinal cord injuries often involves surgery, either directly after an injury occurs or at a later date. Surgery for spine injuries is intended to ease spinal compression and stabilize the spine. Surgical procedures can involve shifting vertebrae, removing bone, or altering spinal placement with implantable devices. Patients with significant spinal trauma may require urgent surgical intervention.

Surgical treatments can be complemented by rehabilitative physical therapy to improve mobility. Spinal cord injury specialists also treat complications arising from a spinal injury, such as respiratory or bladder conditions. Some patients with spinal cord injuries may require lifelong treatment. Spinal cord injury specialists aim to help these patients successfully adjust and lead an improved quality of life. An emerging treatment for spinal cord injuries is neural prosthetics, which replicate patients' lost nerve function. Neural prostheses may be used as artificial body parts or assistive devices that patients may cognitively control. Other assistive devices include wheelchairs and scooters.

Spinal cord injury specialists may collaborate with physical therapists, radiologists, neurologists, urologists, and orthopedists.

• The bladder, which stores urine.
• The urinary sphincters, which are muscles around the opening of the bladder that hold urine in.
• The urethra, which is the tube where urine flows out of the body.

Urodynamics tests are normally performed together as one series, but depending on patients' symptoms, only one or some of them may be necessary. The most common tests are:

• Cystometrogram, which measures the amount of urine the bladder can store and how full it is before someone has the urge to urinate. Doctors may order this test if she suspects their patient has a weak bladder.
• Pressure flow study, which measures the pressure in the bladder while urinating. This test helps locate a blockage in the bladder.
• Uroflowmetry, which measures how much and how fast urine flows out of the body. This test is usually recommended when patients have difficulty urinating or they have a slow stream.
• Urethral sphincter electromyography, which measures how strong the muscles and nerves in the bladder and sphincters are. Doctors may request this test if the problem they are experiencing is linked to muscle or nerve damage in the lower urinary tract.
• Urethral pressure profile, which measures the pressure along the urethra while the bladder is gradually filled with fluid. Low pressure could mean someone has a weak urethra, a contributing factor to urinary incontinence (loss of bladder control).

For a few hours following a urodynamics study, patients will likely feel some soreness or discomfort. It is recommended to drink at least one glass of water every half hour for two hours to relieve these symptoms. Holding a warm, moistened washcloth over the area where discomfort is felt or taking a warm bath may also help. Results for cystrometrograms and uroflowmetry are typically available immediately after the test, but results for the other tests may take a few days. When doctors have reviewed a patient's test results, he or she will discuss them with the patient, along with any treatments the patient may need.