When many people picture chiropractic care, they imagine a quick adjustment followed by a loud cracking sound. While that sound can occur during some treatments, it is not the purpose of an adjustment, and it is not required for chiropractic care to be effective.
Chiropractic care includes many different techniques. A qualified chiropractor can select an approach based on a patient's symptoms, health history, comfort level, mobility, and treatment goals. Some techniques involve a quick, controlled movement. Others use gentle pressure, slow mobilization, instruments, tables, stretching, or soft-tissue work.
The right treatment is not defined by how loud it sounds. It is defined by whether it is appropriate, comfortable, and helpful for the patient.
What Causes the Cracking Sound?
The familiar "pop" or "crack" is generally called an audible cavitation. It occurs when a joint is quickly moved or distracted, creating a change in pressure within the joint.
Research using real-time imaging suggests that the sound is associated with the rapid formation of a gas-filled cavity within the synovial fluid of a joint. In other words, the sound is not a bone moving back into place. It is also not evidence that a vertebra was "out of alignment" and has now been corrected.
A cracking sound may occur during a high-velocity, low-amplitude adjustment, but it may not occur every time. Whether a sound is produced can depend on the joint, the technique, the patient's anatomy, and the amount and direction of movement.
The Sound Is Not the Goal of an Adjustment
The goal of an adjustment is not to make a joint "crack". Depending on the patient and the treatment plan, goals may include:
- Improving joint movement
- Reducing pain or stiffness
- Supporting normal range of motion
- Decreasing muscle guarding
- Improving a patient's ability to move and function
- Helping a patient participate in exercise and daily activities
A systematic review examining audible pops found no evidence that the presence of a pop was associated with better pain outcomes. Patients experienced similar results whether or not an audible sound occurred. This supports what many chiropractors already know: a quiet adjustment can be just as intentional and clinically appropriate as one that produces a pop.
Patients should never feel that an adjustment was unsuccessful simply because they did not hear a cracking sound. The sound is an incidental effect of some techniques, not a measurement of treatment quality.
Chiropractic Techniques Do Not All Involve a Crack
A chiropractor may use one or more of the following approaches:
Manual spinal manipulation
This may involve a short, controlled thrust delivered to a specific area of the spine. It can sometimes produce an audible cavitation, but not always.
Mobilization
Mobilization uses slower, gentler movements to help improve joint motion. It typically does not involve a quick thrust and may not produce a sound.
Instrument-assisted adjustments
Handheld instruments can deliver a carefully controlled impulse. This approach may be useful for patients who prefer a lighter technique or who are not comfortable with traditional manual manipulation.
Flexion-distraction techniques
These techniques use a specialized table and gentle, rhythmic movements. They are often used as part of a broader treatment plan for certain types of back or leg symptoms.
Drop-table techniques
A drop table allows a section of the table to move a short distance as the chiropractor applies a controlled force. The technique is designed to reduce the amount of force needed and may or may not produce an audible sound.
Soft-tissue therapy, stretching, and exercise
Chiropractic care may also include muscle work, stretching, posture guidance, and therapeutic exercises. These services can complement an adjustment and help patients build strength, improve mobility, and manage recurring symptoms.
Research comparing different spinal manipulation procedures suggests that differences between techniques are generally small and may not be clinically meaningful for many patients. This reinforces the importance of choosing care based on clinical judgment, patient preference, comfort, and individual goals, not on whether a technique produces a dramatic sound.
Three Potential Benefits of Chiropractic Care
Chiropractic care is not appropriate for every condition, and results can vary. However, research and clinical guidelines support spinal manipulation and related conservative care for some musculoskeletal problems, particularly when treatment is individualized and combined with active strategies such as exercise.
1. Relief from some types of low back pain
Spinal manipulation may provide short-term improvements in pain and function for some adults with low back pain. It is commonly used as one option among several conservative treatments, including exercise, education, and physical therapy.
The goal is not simply to reduce discomfort temporarily. A comprehensive plan also helps patients move more confidently and return to everyday activities.
2. Improved mobility and physical function
Pain and stiffness can make ordinary movements, such as turning, bending, walking, or sitting, more difficult. Appropriate manual therapy and mobilization may help improve range of motion and reduce the feeling of stiffness.
Improved mobility can make it easier for patients to participate in strengthening exercises, work safely, and perform daily activities.
3. Support for some neck-pain conditions
Research indicates that spinal manipulation and mobilization can help some people with neck pain and related disability. Importantly, a cracking sound is not necessary for improvement. Both thrust and non-thrust approaches may be considered depending on the patient's needs and preferences.
A chiropractor should screen for potential causes of neck pain and refer a patient for medical evaluation when symptoms suggest that chiropractic care may not be appropriate.
Chiropractic Care Should Be Individualized
There is no single technique that is right for every patient. A responsible chiropractic evaluation considers:
- The location, severity, and duration of symptoms
- Previous injuries and medical conditions
- Medications and other treatments
- Neurological symptoms
- Mobility and functional limitations
- Patient preferences and comfort
- Whether referral or co-management with another provider is needed
Chiropractic care also works best when it is part of a broader plan. Depending on the individual, care may include education, exercise, physical therapy, massage, acupuncture, or primary care coordination.
The Bottom Line
A chiropractic adjustment does not need to crack to work. The sound is usually a joint cavitation caused by a rapid pressure change, not a sign that a bone has been "put back in place." Current research does not show that hearing a pop leads to better pain outcomes.
Patients have many options, including gentle and non-thrust techniques. The most appropriate approach is the one that is safe, evidence-informed, comfortable, and matched to the patient's condition and goals.
References
- Kawchuk, G. N., et al. "Real-Time Visualization of Joint Cavitation." PLoS ONE, vol. 10, no. 4, 2015, article e0119470. https://doi.org/10.1371/journal.pone.0119470
- Bialosky, J. E., et al. "Impact of Audible Pops Associated with Spinal Manipulation on Perceived Pain: A Systematic Review." Chiropractic & Manual Therapies, vol. 30, 2022, article 16. https://doi.org/10.1186/s12998-022-00454-0
- Côté, P., et al. "The Effectiveness of Spinal Manipulative Therapy in Treating Spinal Pain Does Not Depend on the Application Procedures: A Systematic Review and Network Meta-Analysis." Journal of Orthopaedic & Sports Physical Therapy, vol. 55, no. 2, 2025, pp. 1-14. https://doi.org/10.2519/jospt.2025.12707
- World Health Organization. WHO Guideline for Non-Surgical Management of Chronic Primary Low Back Pain in Adults in Primary and Community Care Settings. World Health Organization, 2023. https://www.who.int/publications/i/item/9789240081789