Pain and Spine Flashcards
Which of the following neural structures transmits light touch and pressure impulses?
A A-gamma fibers
B C fibers
C A-delta fibers
D A-beta fibers
Answer: D
Explanation:
• Light touch is transmitted by A-beta (large, myelinated) fibers.
• C fibers are the other main one to know (they are small, unmyelinated, and transmit pain impulses).
An 83 year-old male presents with low back pain. MRI of the lumbar spine demonstrates 27% slippage of the L4 vertebral body on top of the L5 vertebral body. How would you describe these findings?
AGrade 4 spondylolisthesis
BGrade 3 spondylolisthesis
CGrade 2 spondylolisthesis
DGrade 1 spondylolisthesis
Answer: C
• Spondylolisthesis is the slippage of one vertebral body over the top of another.
• Grade 1 is 1-25% displacement when comparing the two vertebral body surfaces.
• Grade 2 is 26-50% slippage
• Grade 3 is 51-75% slippage
• Grade 4 is 76-100% slippage
• Grade 5 is beyond 100%
During an interlaminar epidural steroid injection, you advance the needle tip between the L4 and L5 laminae, when suddenly the syringe plunger auto-depresses all the way down, evacuating the syringe of its contents. Which of the following is the most appropriate next step?
A Withdraw the needle and obtain oblique x-ray view
B Advance the needle further and confirm with x-ray imaging
C Inject contrast dye
D Withdraw the needle and abort the procedure
Answer: C
Explanation:
• During an interlaminar epidural steroid injection (ESI) the goal is to pierce the ligamentum flavum and enter the epidural space.
• During an interlaminar ESI, a “loss of resistance syringe” is used to confirm entry into the epidural space.
• Upon entering the epidural space, this syringe will automatically depress its contents due to a sudden loss of resistance in its environment. In other words, the syringe plunger is NOT able to auto-inject its contents in the muscle and fascia it travels through on its way through the patient’s back, into the epidural space, due to the resistance of these firm tissues to injection.
• However, upon entering the epidural space, suddenly all this resistance is gone, allowing the syringe to easily auto-inject its contents into the epidural space.
• Thus, when performing an interlaminar epidural steroid injection, the way to confirm successful presence of the needle tip within the epidural space is to advance the needle tip until the syringe plunger depresses all the way down by itself freely.
• Further anteroposterior and lateral view imaging may be obtained to confirm three-dimensional position before injecting contrast dye to view epidural flow of medication.
• Following agreeable flow of contrast dye (into the epidural space, termed an epidurogram), a syringe containing the epidural steroid medication is attached to the needle for injection into the exact same space as the contrast dye.
A 13 year-old female with a history of myelomeningocele at L3-L4 presents for routine checkup. She notes worsening back pain over the past few weeks, and more frequent episodes of urinary incontinence. She denies trauma, fever, or chills. On exam you notice abnormal posture (not documented previously) and knee extension strength is 2/5, but the previous note documents antigravity strength. Which of the following is the most reasonable next step?
A MRI lumbar spine
B Physical therapy
C Urinalysis
D Reassurance
Answer: A
Explanation:
• This patient with spina bifida presents with acute neurologic worsening (progressive weakness, worsening bowel/bladder function, worsening pain), suspicious for tethered cord.
• MRI of lumbar spine is necessary along with a neurosurgery consultation for cord detethering surgery.
• A urinary tract infection would NOT explain worsened leg strength, worsened posture/scoliosis, and worsened bowel/bladder function (typically bladder function alone, possibly with flank pain, would be suspected in urinary tract infection, along with potential fever/chills).
The notion of light touch and pressure sensations inhibiting pain signals is known by what name?
A The Gate Control Theory
B The Bridge Raising Theory
C The Pain Inhibition Theory
D The D’Angelo Theory
Answer: A
Explanation:
• This question describes the Gate Control Theory by which light touch/vibration/pressure impulses on the skin can synapse onto wide dynamic range neurons in the spinal cord and inhibit C-fiber (pain) signals which also synapse onto these neurons, thus inhibiting pain transmission to the brain.
A 65 year-old male presents with 1 year of gradual onset bilateral low back and calf pain. He denies bowel or bladder changes. He also notes leg heaviness worse with walking long distances. He is an avid cyclist but has not been able to enjoy this recently due to the calf pain. On exam, strength and sensation are intact. Which of the following is the most appropriate next step?
A Physical therapy with spinal flexion-biased maneuvers
B Physical therapy with spinal extension-biased maneuvers
C Vascular surgery consultation
D MRI lumbar spine
Answer: C
Explanation:
• This patient suffers from vascular claudication, i.e. narrowing of the blood vessels peripherally leading to poor blood supply to the muscles; thus, using the muscles during exercise leads to muscle ischemia and pain.
• The best option out of the choices is to consult with a vascular surgeon or his PCP for proper management of a vascular problem.
• His symptoms may NOT be severe enough for surgical intervention, but spinal physical therapy iis not going to be the best type of exercise for his vascular claudication, regardless.
• MRI lumbar spine is NOT indicated in a vascular claudication scenario.
• Recall that in lumbar spinal stenosis resulting in neurogenic claudication, leg symptoms are typically improved with forward lumbar flexion; in this patient his symptoms are worsened with forward lumbar flexion (cycling), which is the key component to recognize to answer this question, as cardiovascular exercise in a lumbar flexion position, if it worsens the patient’s leg symptoms, is indicative of vascular claudication.
A 77 year-old female presents with low back pain. MRI of the lumbar spine demonstrates mild slippage of the L4 vertebral body on top of the L5 vertebral body. What is the term you would use to describe these findings?
A Spondyloptosis
B Spondylolysis
C Spondylolisthesis
D Spondylosis
Answer: C
Explanation:
• Spondylosis is defined essentially as chronic “wear and tear” degenerative changes in the spine, such as those listed in the question stem.
• Spondylolisthesis is the slippage of one vertebral body over the top of another.
○ Grade I (1-25%)
○ Grade II (25-50%)
○ Grade III (50-75%)
○ Grade IV (75-100%)
○ Grade V (> 100%) = Spondyloptosis
• Spondylolysis is a vertebrae fracture resulting in a pars interarticularis defect.
• Spondyloptosis is a grade 5 spondylolisthesis (the most severe grade).
If you wanted to target a patient’s back pain by blocking the nerves that innervate the right L4-L5 facet joint, which nerves would you block?
A None of these answers is correct
B L5 and S1 medial branches
C L4 and L5 medial branches
D L3 and L4 medial branches
Answer: D
Explanation:
• In the lumbar spine, a given facet joint is innervated by the higher level of the two, and the level above.
• For example, the L4-L5 facet joint is innervated by the L3 and L4 medial branches.
A 23 year-old male presents to your clinic with gradual onset of 8 months of low back pain worse with moving from sitting to standing. His pain has not improved with physical therapy. You decide to order an MRI of the lumbar spine. It reveals that the first sacral bone (S1 vertebra) failed to fuse with the rest of the sacrum, and is essentially floating superiorly to the rest of the sacrum. What is the most appropriate advice to the patient?
A This typically requires surgical correction
B This typically improves with injections
C This typically requires physical therapy
D This typically is just a normal variant of anatomy
Answer: D
Explanation:
• Transitional lumbosacral anatomy can be described as lumbarization of the sacrum (S1 fails to fuse with the rest of the sacrum, which essentially turns the S1 vertebral body into an “L6” vertebral body) or sacralization of the lumbar spine (L5 fuses with the sacrum to create a very long, fused sacral spine).
• Transitional anatomy is generally regarded as a normal variant of human anatomy and does NOT necessarily by itself cause pain or dysfunction.
• This patient’s MRI findings are likely a red herring to his actual pain generator.
A 56 year-old male complains of 2 months of low back pain radiating into the right lower extremity. MRI of the lumbar spine reveals an L3-L4 paracentral disc herniation. Which of the following nerves is most likely being compromised?
A L5
B L4
C L3
D L2
Answer: B
Explanation:
• In the lumbar spine a central or paracentral disc herniation will involve the descending nerve root at that level (e.g. at the L3-L4 level, the L3 nerve is exiting via the neuroforamen, and the L4 nerve is descending to exit via the neuroforamen at the L4-L5 level).
A 59 year-old male presents with low back pain of gradual onset for the past 8 months. He denies trauma, numbness, tingling, or weakness. On exam he has intact strength and sensation. Rotating his torso to the left while extending his spine reproduces his pain, as does the same maneuver towards the right. FABER and thigh thrust tests are negative. There is tenderness to palpation of the lumbar paraspinals, producing non-concordant pain. What is the most likely diagnosis?
A Myofascial pain
B Lumbar facet arthropathy
C Lumbar stenosis
D SI joint dysfunction
Answer: B
Explanation:
• The physical exam maneuver described in the question is the facet joint loading maneuver for the lumbar spine. Challenging and loading the lumbar facet joints and reproducing the patient’s low back pain raises suspicion for lumbar facet arthropathy as his primary pain generator.
• He does have some myofascial pain, but palpation of these muscles does NOT reproduce his usual pain.
• SI joint tests are negative for this patient.
• Lumbar stenosis pain typically radiates into the lower limbs +/- paresthesias.
A 44 year-old female presents with neck pain radiating down the right arm. MRI reveals an acute C6-C7 disc herniation. Which nerve root is most at risk for compression?
A C8
B C7
C C6
D C5
Answer: B
Explanation:
• In the cervical spine, nerve roots exit just above their vertebral body level.
• Thus, the C7 nerve is exiting the spinal canal at the C6-C7 level and is the most likely nerve root impinged at this level by a herniated disc.
Bifid spinous processes are featured in which cervical vertebrae?
A C2-C7
B C3-C7
C C2-C6
D C1-C6
Answer: C
Explanation:
• C2-C6 feature bifid spinous processes.
A 41 year-old male presents with 9 months of gradual onset low back pain. He denies trauma. He has tried physical therapy and ibuprofen but has only received minimal improvement. On exam while supine, hanging one leg off the side edge of the exam table reproduces his low back pain. Which of the following is the most reasonable next step?
A Spinal cord stimulator trial
B Sacroiliac joint injection
C Lumbar facet joint injection
D Lumbar facet medial branch block
Answer: B
Explanation:
• This patient with low back pain secondary to sacroiliac joint dysfunction (positive Gaenslen test) and failing conservative treatments should consider a sacroiliac joint injection as the next step in care.
• A spinal cord stimulator trial is used in very refractory, chronic cases.
A 24 year-old male sustains a Maisonneuve fracture. This is complicated by neurologic weakness in the fibularis longus and brevis muscles, and impaired sensation over the lateral lower leg and dorsum of the foot. Over the next few months he develops abnormal sweating in the lower leg, as well as excruciating pain when putting on a sock. What is the most likely diagnosis?
A Anxiety-induced hyperalgesia
B Lumbar radiculitis
C Complex regional pain syndrome type 2
D Complex regional pain syndrome type 1
Answer: C
Explanation:
• Complex regional pain syndrome (CRPS) comes in two types.
• Type 1 is sympathetically mediated pain due to an unknown etiology (usually occurs after trauma) that results in an area of the body experiencing increased neuropathic pain, hypersensitivity, allodynia, skin vasomotor changes, and edema.
• X-rays will show periarticular osteopenia.
• Type 2 is these symptoms in the context of a known, documented peripheral nerve injury; Type 2 is also called causalgia.
• Treatment:
○ Aggressive daily ROM and use of the affected body part
○ Oral corticosteroids
○ NSAIDs
○ Anticonvulsants
○ Beta blockers
○ Topical medications
○ Desensitization therapy
○ TENS
• Stellate ganglion block is the best diagnostic test, and can also be therapeutic.
A 68 year-old male presents with gradual onset low back pain for the past 2 years. He found a recent physical therapy course to be too painful to endure. Acetaminophen provides minor pain relief. He denies trauma, numbness, tingling, or weakness. On exam he has intact strength and sensation. Rotating his torso to the left while extending his spine reproduces his pain, as does the same maneuver towards the right. Gaenslen test is negative. What is the next best step?
A Spine surgery consult
B Repeat physical therapy with stronger pain medications
C MRI lumbar spine
D X-ray lumbar spine
Answer: C
Explanation:
• This patient suffers from lumbar facet arthropathy, as evidenced by his positive physical exam maneuver which challenges the lumbar facet joints.
• Initial therapy is oral medications (acetaminophen, NSAIDs) and physical therapy.
• Failing this, MRI of the lumbar spine and facet joint interventions should be considered.
• The purpose of the MRI is to ensure that it is safe to move forward with spine injections/interventional procedures such as medial branch blocks.
• Occasionally the MRI will show a more serious surgical issue for which an X-ray-guided spinal procedure would NOT have been appropriate or safe to perform.
A 45 year old female complains of severe pain when you apply light touch to the skin of her hand. What is the name of this phenomenon? AAllodynia BDysesthesia CHyperpathia DHyperalgesia
Answer: A
Explanation:
• Allodynia: pain elicited from a normally nonpainful stimulus.
• Hyperalgesia is increased pain from a normally painful stimulus.
• Dysesthesias are abnormal, unpleasant sensations.
• Hyperpathia vs. hyperalgesia is too nuanced for you to be tested on it on Part I boards.
The C4-C5 facet joint in the spine is innervated by which of the following nerves? AC5 and C6 medial branches BC4 and C5 medial branches CC3 and C4 medial branches DThe C4 medial branch
Answer: B
Explanation:
• In the cervical spine, the facet joints are innervated by the same medial branches belonging to the levels of the facet joint in question; e.g. the C4-C5 facet joint is innervated by the C4 and C5 medial branches.
