Passive Accessory Intervertebral Movements (PAIVMs)

Passive Accessory Intervertebral Movements (PAIVMs) are a vital component in the assessment and treatment of spinal dysfunctions. These movements, commonly used in manual therapy, help in diagnosing and treating various conditions affecting the vertebral column. As orthopedic surgeons, understanding PAIVMs and their application can enhance your clinical approach, particularly when dealing with spinal pathologies.

Understanding PAIVMs

Passive Accessory Intervertebral Movements are specific manual techniques applied to individual vertebrae to assess joint play and the mobility of the spinal segments. These movements are essential in evaluating the integrity and function of the vertebral joints. By applying controlled pressure to specific areas of the spine, clinicians can detect abnormalities in movement, such as hypomobility, hypermobility, or pain response, which may indicate underlying pathology.

See Also: Cervical Spine Range of Motion

Clinical Application of PAIVMs

There are two primary types of Passive Accessory Intervertebral Movements commonly used in clinical practice:

• Posteroanterior Central Vertebral Pressure (PACVP)
• Posteroanterior Unilateral Vertebral Pressure (PAUVP)

Posteroanterior Central Vertebral Pressure (PACVP)

In PACVP, the patient lies prone with their forehead resting on the back of their hands. The examiner begins by palpating the spinous processes of the cervical spine, starting from C2 and moving down to T2. The examiner’s thumbs are placed on the spinous process of the targeted vertebra, applying a slow and controlled anterior-directed pressure. This technique “springs” the vertebra forward, allowing the clinician to feel the movement’s quality and end feel.

PACVP is particularly useful in detecting hypomobility, which may present as abnormal resistance, altered end feel, or reproduction of pain. The technique can be repeated multiple times to assess the vertebra’s movement quality and to determine the end range. When the adjacent spinous process begins to move, the end range for the target vertebra is reached, providing a clear indication of its mobility status.

See Also: Spine Movements

Posteroanterior Unilateral Vertebral Pressure (PAUVP)

The PAUVP technique involves applying pressure laterally to the spinous process, targeting either the lamina or transverse process of the vertebra. The examiner’s thumbs move approximately 2 to 3 cm laterally from the spinous process to rest on the transverse processes. An anterior springing pressure is then applied, similar to the PACVP, which results in minimal rotation of the vertebral body.
During PAUVP, palpation of the spinous process will reveal a slight lateral movement toward the side of applied pressure. As with PACVP, the end range is determined when the adjacent spinous process begins to rotate. Both sides of the vertebra should be assessed and compared to identify any asymmetry in mobility, which may suggest unilateral restrictions or dysfunctions.

Clinical Significance

Passive Accessory Intervertebral Movements are a crucial diagnostic tool in the hands of an experienced clinician. They provide valuable information about the vertebral segment’s mobility and can help pinpoint the source of pain or dysfunction. By integrating PAIVMs into your clinical practice, you can enhance your ability to diagnose spinal issues accurately and tailor your treatment approach to the specific needs of your patients.

For orthopedic surgeons, mastering PAIVMs can significantly improve the diagnostic process and lead to better outcomes for patients with spinal disorders. These techniques, while seemingly simple, require a deep understanding of spinal anatomy and biomechanics, as well as a refined sense of touch to detect subtle abnormalities. By incorporating PAIVMs into your clinical repertoire, you can offer more precise and effective care to your patients, ensuring their spinal health is managed with the utmost expertise.

Technical Considerations

For optimal results, clinicians should:

• Start with a low-force, gentle assessment to feel the movement without causing discomfort.
• Use the whole hand rather than just the thumbs to control the vertebra’s movement, reducing soft tissue deformation and improving patient comfort.
• Displace soft tissue to enable more direct contact with the vertebra, allowing for a more precise and comfortable assessment.

Reliability

While the reliability of PAIVM techniques has been questioned, studies suggest that the quality of these studies is often inadequate. However, when considering the clinical context—comparing side-to-side and above-below mobility, therapists can effectively discern differences in mobility and provoke symptoms relevant to the patient’s condition. Advanced clinicians often use a hybrid approach, starting with a gentle, exploratory assessment to identify relevant segments before applying more targeted, detailed techniques.

References

• Clinical Orthopedic Manual Therapy Techniques
• Spinal Manipulation in Manual Therapy: Evidence and Clinical Practice
• Physiopedia – PAIVMs of the Cervical Spine – Assessment
• Abbott JH, Flynn TW, Fritz JM, Hing WA, Reid D, Whitman JM. Manual physical assessment of spinal segmental motion: intent and validity. Man Ther. 2009 Feb;14(1):36-44. doi: 10.1016/j.math.2007.09.011. Epub 2007 Nov 7. PMID: 17997344. Pubmed