Joint manipulation is a type of passive movement of a skeletal joint. It is usually aimed at one or more 'target' synovial joints with the aim of achieving a therapeutic effect.

Many definitions of joint manipulation have been proposed. The most rigorous definition, based on available empirical research is that of Evans and Lucas: "Separation (gapping) of opposing articular surfaces of a synovial joint, caused by a force applied perpendicularly to those articular surfaces, that results in cavitation within the synovial fluid of that joint." The corresponding definition for the mechanical response of a manipulation is: "Separation (gapping) of opposing articular surfaces of a synovial joint that results in cavitation within the synovial fluid of that joint." In turn, the action of a manipulation can be defined as: "A force applied perpendicularly to the articular surfaces."

A modern re-emphasis on manipulative therapy occurred in the late 19th century in North America with the emergence of osteopathic medicine and chiropractic medicine. In the context of healthcare, joint manipulation is performed by several professional groups. In North America and Europe, joint manipulation is most commonly performed by chiropractors (estimated to perform over 90% of all manipulative treatments), American-trained osteopathic physicians, occupational therapists, physiotherapists, and European osteopaths. When applied to joints in the spine, it is referred to as spinal manipulation.^{[citation needed]}

Manipulation is known by several other names. Historically, general practitioners and orthopaedic surgeons have used the term "manipulation". Chiropractors refer to manipulation of a spinal joint as an 'adjustment'. Following the labelling system developed by Geoffery Maitland, manipulation is synonymous with Grade V mobilization, a term commonly used by physical therapists. Because of its distinct biomechanics (see section below), the term high velocity low amplitude (HVLA) thrust is often used interchangeably with manipulation.^{[citation needed]}

Manipulation can be distinguished from other manual therapy interventions such as joint mobilization by its biomechanics, both kinetics and kinematics.

Until recently, force-time histories measured during spinal manipulation were described as consisting of three distinct phases: the preload (or prethrust) phase, the thrust phase, and the resolution phase. Evans and Breen added a fourth 'orientation' phase to describe the period during which the patient is oriented into the appropriate position in preparation for the prethrust phase.

When individual peripheral synovial joints are manipulated, the distinct force-time phases that occur during spinal manipulation are not as evident. In particular, the rapid rate of change of force that occurs during the thrust phase when spinal joints are manipulated is not always necessary. Most studies to have measured forces used to manipulate peripheral joints, such as the metacarpophalangeal (MCP) joints, show no more than gradually increasing load. This is probably because there are many more tissues restraining a spinal motion segment than an independent MCP joint.^{[citation needed]}

The kinematics of a complete spinal motion segment when one of its constituent spinal joints are manipulated are much more complex than the kinematics that occur during manipulation of an independent peripheral synovial joint. Even so, the motion that occurs between the articular surfaces of any individual synovial joint during manipulation should be very similar and is described below.^{[citation needed]}