Spinal Stenosis/Lower Back Pain Flashcards
Neutral Spine
Most comfortable posture and pelvic tilt, yielding equal pressure on all vertebrae and disks; pressure on all sides of each disk is equal. Movement out of neutral is what puts pressure, stretching and bulging in disks. Maintaining the natural cervical lordosis, thoracic kyphosis, and lumbar lordosis.
Typical Causes of Back Pain
- Poor physical fitness, obesity, reduced muscle strength and endurance, or poor body mechanics are most common causes.
- Less than 1% of back pain is due to ‘serious’ spinal disease (tumor, infection).
- Less than 1% is from inflammatory disease, and less than 5% is true nerve root pain.
- Depression or anxiety can also worsen or cause lower back pain.
Problems caused by changes in structure/mechanics of lower back:
- SCIATIC PAIN (nerve entrapped by herniated disk)
- SPINAL STENOSIS (narrowing of intervertebral foramen, decreasing space for nerve to enter/exit spine)
- FACET JOINT PAIN (inflammation or changes in spinal joints)
- SPONDYLOSIS (stress fracture of dorsal to transverse process)
- SPONDYLOLISTHESIS (one vertebra slips on another)
- HERNIATED NUCLEUS PULPOSUS (stress tears fibers of disk causing outward bulge of pulposus; presses on spinal nerves and causes symptoms like nerve entrapment)
- COMPRESSION/STRESS FRACTURES (usually result of osteoporosis and occur in vertebrae)
Areas of Spinal Stenosis
(*May occur together)
1) Lateral Recess Stenosis: foraminal stenosis (narrowed foramina) in which spinal nerve is compressed just before it reaches intervertebral foramen.
2) Far Lateral Stenosis: foraminal stenosis in which spinal nerve has already exited intervertebral foramen.
3) Central Canal Stenosis: caused when vertebral foramina (vertebral canal) narrow, giving spinal cord itself less space, causing pain/dysfunction anywhere below. Most common in lumbar or cervical spine.
Foot Drop
Weakness or paralysis of muscles involved in lifting the front of the foot. Damage to peroneal nerve. Can be caused by nerve injury (in spine, hip or knee), muscle or nerve disorders, or brain/spinal cord disorders. A nerve root injury (“pinched nerve”) in the spine can cause foot drop.
Oral Steroids to Alleviate Back Pain
Oral steroids are designed to work in the same way as the hormones produced by your adrenal glands in response to stress and injury. When the corticosteroids you take raise your body’s natural adrenal hormones above their normal levels, this reduces inflammation. Corticosteroids also suppress your immune system, which helps people who suffer from autoimmune conditions (such as RA) but can also decrease your ability to fight infection. In most cases, you will take your strongest dose on the first day of therapy and taper down until you do not have any medication left (1-2 wks). Oral steroids do not require MRI or radiation exposure, and may pose less of a risk for some patients.
Epidural Steroid/Corticosteroid Injections (ESIs)
Common treatment option for many forms of lower back pain and leg pain. They have been used for decades and are considered an integral part of the nonsurgical management of sciatica and lower back pain. Deliver a more concentrated, instantaneous dose of corticosteroids with a lower degree of systemic (whole body) side effects than oral steroids. Involves injecting a local anesthetic and a steroid medication directly into the epidural space that surrounds the spinal cord and nerve roots. The role of the injection is typically to provide sufficient pain relief to allow a return to everyday activities and to make progress in physical therapy. It is a step to take prior to surgery.
Goals of Surgical Intervention of Spine
Most are divided into two types: decompressing the nerve, or stabilizing the spine to reduce pain.
DECOMPRESSING the nerve: open transverse foramen to increase space; remove structure such as part of disk/osteophyte that is putting pressure on nerve root.
STABILIZING the spine: use of various hardware such as screws, wires, rods, bone grafts. Also, vertebroplasty (cement injected into fracture) and kyphoplasty (balloon placed in fracture to increase height prior to cement) use cement-like substance to stabilize compression/stress fractures.
Minimally Invasive Spine (MIS) Surgery
In general, the goal is to stabilize the vertebral bones and spinal joints and/or relieve pressure being applied to the spinal nerves — often a result of conditions such as spinal instability, bone spurs, herniated discs, scoliosis or spinal tumors. As opposed to open spine surgery, minimally invasive surgical approaches can be faster, safer and require less recovery time because of the reduced trauma to the muscles and soft tissues (compared to open procedures). Some are outpatient procedures with local anesthesia. Use of devices to avoid injury to structures (muscles) of back, such as tubular retractor (requires only small incisions for tube and progressive dilation of soft tissues to keep them aside as opposed to cutting through). MIS Procedures include: Kyphoplasty, spinal fusion, laminectomy, discectomy/microdiscectomy, spinal cord stimulator placement, interspinous spacer placement, and cervical disk replacement.
Open Spine Surgery
Surgeon creates a large incision (usually about six inches long) in the back and dissects the spinal muscles to pull them away from the bone in a process called retraction. Once they visualize the bones of the spine, they will begin the necessary spinal procedure. Certain open spine surgeries require the surgeon to go in from the front through a large abdominal incision. Requires anesthesia, large incisions, muscle retraction, long surgery times, hospitalization and long recovery.
Interspinous Spacer (X-Stop Device)
During a surgical procedure that is less invasive than traditional open back surgery, the X-STOP Spacer is implanted between two bones in the back of the spine called the spinous processes-at the level of the pinched nerve. These spinous processes can be felt when you run your fingers down your spine. Ligaments in the spine, which are bands of tissue linking two bones, may help to keep the spacer in the desired location. By “unpinching” the nerve, the X-STOP Spacer may relieve the kinds of pain and discomfort caused by lumbar spinal stenosis (LSS). Usually for pts 50 or older with LSS.
Spinal Fusion
Spinal fusion is surgery to permanently connect two or more vertebrae in your spine, eliminating motion between them. Spinal fusion involves techniques designed to mimic the normal healing process of broken bones. During spinal fusion, your surgeon places bone or a bonelike material within the space between two spinal vertebrae. Metal plates, screws and rods may be used to hold the vertebrae together, so they can heal into one solid unit. Used to improve stability, correct a deformity or reduce pain (ie: spinal deformities, fractures, spinal weakness/instability, or herniated disk).
Benefits of Minimally Invasive Surgery (MIS)
- Better cosmetic results (smaller incisions)
- Less blood
- Reduced risk of muscle damage (not cutting any muscle)
- Reduced risk of infection/postop pain
- Faster recovery time/less rehab
- Diminished reliance on postop pain meds
Vertebroplasty vs Kyphoplasty
Both are MIS procedures used to treat painful vertebral compression fractures in the spinal column, which are a common result of osteoporosis. About 75% of pts regain lost mobility/become more active. Should be done within 8 wks of fracture. Used in elderly or those with impaired bone healing (osteoporosis), or compression due to a malignant tumor.
VERTEBROPLASTY: imaging guidance used to inject a cement mixture into the fractured bone through a hollow needle.
KYPHOPLASTY: insert a balloon into the fractured bone (also through hollow needle) to create a space (add height) and then it’s removed and cavity is filled with cement.
Back Pain Statistics
- In US, low back pain is most common type of pain (27%) and leading cause of disability in <45 yo
- Number 1 cause of years lived with disability in the world & U.S.
- 1 in 12 ppl experience frequent back pain
