Functional Anatomy: Spine & Back Muscles

In a patient presenting with acute lower back pain following a strain injury, which of the following anatomical structures is LEAST likely to be directly involved, assuming no pre-existing conditions?

A patient reports pain exacerbated by extension and lateral flexion of the lumbar spine. Advanced imaging reveals no disc herniation or neural compression. Which of the following structures are MOST likely implicated?

A surgeon is planning a posterior approach to decompress the spinal canal at the level of L4-L5. In what order will the surgeon encounter layers of muscle?

A researcher aims to investigate the contributions of different muscle groups to spinal stability during complex movements. Which of the following methods would be MOST effective in isolating and quantifying the activity of individual deep intrinsic back muscles?

A patient exhibits significant atrophy and weakness in spinal extension and ipsilateral rotation, with no sensory deficits. Imaging reveals a lesion affecting the posterior primary rami of several spinal nerves. Which muscles are MOST likely affected?

A biomechanical engineer is designing a novel spinal implant that aims to restore segmental stability following laminectomy. The design MUST consider the functional implications related to the sacrifice of which structure that are most critical for resisting torsional loads and maintaining lordosis?

A physical therapist is assessing a patient with chronic lower back pain. Upon palpation, they identify hypertonicity and trigger points within the quadratus lumborum (QL) muscle. Which of the following clinical findings would BEST differentiate QL involvement from involvement of the lumbar multifidus?

Following a motor vehicle accident, a patient presents with a spinal cord injury resulting in paralysis. During rehabilitation, electrical stimulation is being considered to activate the intrinsic back muscles. Which of the following parameters would be MOST critical to optimize to selectively target and strengthen the deeper multifidus muscle while minimizing activation of the more superficial erector spinae?

A researcher hypothesizes that age-related changes in the lumbar multifidus muscle contribute to the development of spinal stenosis. Which of the following study designs would provide the STRONGEST evidence to support this hypothesis?

A patient presents with unilateral lower back pain and radicular symptoms down the leg. MRI shows evidence of multifidus atrophy on the affected side. Which of the following mechanisms is MOST likely contributing to the development of these symptoms?

A high-level gymnast complains of lower back pain that worsens with hyperextension-based skills. Palpation reveals tenderness over the spinous process of L5. Imaging shows evidence of spondylolysis. Which of the following muscles, if significantly weakened, would MOST directly contribute to the development of this condition?

A patient who underwent a spinal fusion for a grade II spondylolisthesis at L4/L5 now presents with adjacent segment disease and increased zygapophyseal joint loading at L3/L4. Which of the following intrinsic muscles would be MOST crucial to strengthen to mitigate the increased load and prevent further degeneration at the L3/L4 segment?

A researcher is studying the effect of prolonged sitting on lumbar disc health. IVD hydrostatic pressure increases during sitting. Which of the following scenarios would MOST effectively counteract the harmful increases in intradiscal pressure during prolonged sitting?

A patient presents with chronic neck pain and limited cervical rotation to the right. Examination reveals hypertonicity of the left splenius capitis and cervicis muscles. Which of the following interventions would BEST address the underlying neuromuscular imbalances contributing to the patient's symptoms?

A patient presents with neck pain radiating into the occipital region, accompanied by dizziness and visual disturbances. Upon examination, significant trigger points are identified in the suboccipital muscles. Dysfunction in which anatomical structure would MOST DIRECTLY explain the patient's cranial symptoms?

A competitive weightlifter is training for a meet and reports increasing lower back pain with heavy squats and deadlifts. Clinical examination reveals hypertrophy of the erector spinae muscles, but paradoxical weakness during lumbar extension. Which of the following BEST explains this paradoxical weakness?

A physical education professor is guiding students through exercises. She is describing eccentric muscle contractions. Which scenario involves BOTH the multifidus, erector spinae, and abdominal muscles functioning primarily through eccentric contractions, while lowering a heavy barbell?

A researcher is performing a cadaveric study of the innervation patterns of the intrinsic back muscles. To accurately trace the path of the dorsal rami of the spinal nerves, the researcher must carefully dissect through which of the following structures?

An exercise physiologist is designing a rehabilitation program for athletes recovering from lumbar disc herniations. To selectively strengthen the multifidus muscle without exacerbating pain, which of the following approaches should be prioritized?

A surgeon is interpreting a post-operative MRI scan following a complex reconstructive procedure involving the cervical spine. Which anatomical landmark would MOST accurately differentiate the longus colli muscle from the longus capitis muscle?

A patient presents with torticollis, characterized by unilateral shortening of the sternocleidomastoid muscle leading to head tilt and rotation. To best restore normal length of the SCM, which of the following muscles must be concentrically strengthened to create a mechanical disadvantage for the SCM?

You are counseling a patient who is considering lumbar fusion surgery for chronic back that has failed conservative measures. A key concern is the increased loading and degeneration of adjacent segments following fusion. Which of the following strategies would be MOST effective in mitigating this risk post-operatively?

In performing a lumbar puncture (spinal tap), knowledge of the anatomy is paramount. Once the skin and subcutaneous tissue have been incised in the midline, which of the following ligaments is the next encountered?

Which ONE of the following statements is INCORRECT with regards to intrinsic back muscle function?

A 35-year-old patient is diagnosed with ankylosing spondylitis, an inflammatory arthritis primarily affecting the spine. Which one of the following muscles is LEAST likely to be directly and negatively impacted by the progression of this disease?

A researcher is planning to analyze the fiber type composition of the multifidus muscle in patients with chronic lower back pain versus healthy controls. Which methodology would be optimal for ACCURATELY quantifying the cross-sectional area of Type I fibers versus Type II fibers?

Which of the following is the MOST accurate statement with regards to lumbar spinal stenosis?

Which statement is LEAST accurate with regards to the spinal nerve?

A martial artist injures his cervical spine, damaging his intrinsic muscles. If he has impaired stabilization during rotation to the left, which of the following muscles are mostly damaged?

An anatomist is performing virtual dissections of the spine. He wants to study what lies directly anterior to the longus colli. What will he MOST likely encounter?

An individual has significant weakness in thoracic extension, but can fully extend the cervical and lumbar spine. Which of the following muscles is MOST likely involved?

What are the functional consequences of lumbar multifidus atrophy?

Which of the erector spinae muscle groups is MEDIAL, closest to the midline?

You are an exercise physiologist. With regards to breathing, which deep extrinsic back muscle provides movement of the ribs during forced expiration?

The longus colli muscle is important for stabilizing the vertebrae. When it contracts unilaterally, what movement occurs?

A student is practicing spinal palpation, and wants to find the spinous process of CVII. What spinal level is this?

Where does the spinal cord lie with regards to the spinal canal?