Musculoskeletal Examination Principles

Musculoskeletal examination refers to physical examination of the musculoskeletal system. The primary purpose is to find objective information about the index condition and it complements the history taking in the process of formulating a clinical diagnosis. It also has a secondary effect of enhancing the doctor-patient relationship if done sensitively. 
==Components==
There are three elements to the physical examination. They are colloquially termed "look, feel, move" by Apley; or more precisely termed inspection, palpation, and movement testing. The sequence "look, feel, move" is appropriate for fractures, but for most other musculoskeletal conditions the sequence "look, move, feel" is more suitable. A fourth category is special tests.
The New Zealand musculoskeletal examination system has been somewhat influenced by the osteopathic approach. The osteopathic perspective looks at the musculoskeletal examination as a tool for identifying somatic dysfunction, and calls the approach "TART" i.e. tenderness, asymmetry, restricted motion, tissue texture changes.
The musculoskeletal exam is not the neurological exam. A neurological examination is only appropriate if there are neurological symptoms.
===Inspection===
Observations may include both general and specific findings.
*General: gait, gross movements (dynamic posture); standing, sitting, deformities (static posture).
*Specific: pertaining to the affected area, namely discolouration, scars, swelling, local deformities.
===Palpation===
There are three components to palpatory skills: perception (awareness and knowledge), concentration (amplification), and interpretation (making sense of what you feel). 
Palpation should be done in layers. The examiner should be ever-conscious as to the local anatomy. Palpation involves discriminating small differences on a continuum, identifying shapes, assessing tissue texture changes, gauging depth, comparing relative positions, sensing subtle changes in temperature and moisture, and identifying the direction of fibres in tissues. 
Different parts of our hands have different utilities in palpation. Fine tactile discrimination is assessed using the finger tips, vibration is assessed using the palmar aspect of the MCP joints, stereognosis (gross shape) is assessed using the palms, and depth is assessed using the tips of the thumbs. 
All accessible tissues and structures are potential sites for palpation: skin, subcutaneous and deep fascia, vessels, nerves, muscle and MT junctions, tendons, entheses, bones, joints, ligaments, etc. 
Common errors in palpation arise from poor anatomical knowledge, poor concentration, applying too much pressure, and applying too much movement. 
The most pertinent finding for palpation is tenderness. Tenderness may be quite focal, or diffuse. Finding tenderness can enhance the doctor-patient relationship and puts them in control to some extent of their pain problem. It lessens the chance of "guruism" as you can't trick the patient into feeling pain. If tenderness is felt, ask the patient if it is similar to their index pain, and whether it causes any somatic referred pain. 
Other signs on palpation are sudomotor changes on skin drag, skin sensitivity on pinch roll, alterations of tissue texture, masses, and abnormalities of bony landmarks. Tissue texture frequently takes on a hard or doughy quality, and represents altered autonomic activity in the dysfunctional area.
The osteopathic TART perspective views changes depending on the chronicity of the condition. Some of the changes relate to differences in vasodilation and autonomic effects. 
 	Acute 	Chronic
Temperature 	Warm 	Cool
Texture 	Boggy, rough 	Thin, smooth
Moisture 	Moist 	Dry
Tension 	Increased 	Ropey, stringy
Tenderness 	Greatest 	Present but less
Oedema 	Yes 	No
Erythema test 	Redness lasts	Fades quickly
Viscero-somatic effects	Minimal 	Common
===Movement Testing===
Movements assessed through active range, passive range, accessory motion, and challenging restraints. Any restrictions for be noted for both active and passive range of motion, and the cause noted e.g. due to pain or weakness.
For active range of motion assessment, the patient assumes a neutral position and moves the body part in each physiological direction as far as possible. 
The movements in question depend on the joint. Spinal motions are extension, flexion, side-bending, and rotation. The appendicular joints are extension, flexion, abduction, adduction, external rotation, and internal rotation. Ranges are visually estimated or measured using a goniometer or inclinometer.
The examiner records any reduction in range of motion and any associated pain or weakness.
Passive range of motion is tested through the same ranges with the examiner providing passive force. Again note any restriction and whether it is due to pain, weakness, or other.
Accessory movements also known as joint play are those motions which can't be performed actively in isolation, but can be performed passively by an examiner. The examiner fixes one body part and moves the other relative to the fixed point. Accessory movements can be translations or rotations. The ranges are generally small. 
Accessory movements provide easier assessment of end-feel. A judgement is made whether it feels normal (springy), soft, or hard. 
Challenging restraints are restraints to movement that can arise from pain, joint (bony restriction), muscle/ligament shortening, and joint capsules. Restraints are easier to test for large joints (hip, knee, shoulder etc), than smaller joints (intervertebral joints, facet joints, etc).
Restraints are tested actively, passively, and through accessory movements. The examiner judges whether the restraint is due to pain, obstruction by a body or soft tissue, antagonistic muscle action, or tethering by ligaments or fascia. Examples of this are the painful arc in subacromial pain syndrome, and the apprehension sign in glenohumeral joint instability.
== Follow Up ==
Follow up examination findings can be used to monitor treatment or "disease" progress. For example the degree of tenderness, location of tenderness, range of motion, presence/absence of muscle spasm. This adds another dimension to monitoring over and above pain and functional ratings.
== Other Benefits ==
The musculoskeletal examination may help in detecting unrelated but serious conditions such as Parkinson's disease, vascular insufficiency, melanoma, secondary lymphoma, dissecting carotid aneurysm, discitis, psoriatic arthropathy, etc.
With the laying on of hands, oxytocin is released into the blood from the posterior lobe of the pituitary gland.
== Evidence Base ==
Clinical epidemiology is not medical epidemiology. It is the philosophical and rational basis for determining truth in the practice of medicine. It combines statistical methods of epidemiology with clinical reasoning to study clinical populations.Logan, Richard. “Clinical Epidemiology: A Basic Science for Clinical Medicine.” Journal of Epidemiology and Community Health vol. 46,5 (1992): 549.
The particular truths relevant in the musculoskeletal examination are reliability, validity, and efficacy. A physical examination manoeuvre should be assessed as we assess any diagnostic test.
There are multiple problems in applying evidence based medicine to musculoskeletal medicine, such as:
* Pain is the most common symptom and is inherently subjective with no objective means of measuring it.
* Pain pathways are complex, for example referred pain, descending modulation, poor localisation for deep pain, and more.
* There is the "shifting sands" problem of anatomical structures
* Examination findings can vary day to day
* Examination findings vary between the level of training of examiners
* Different examiners may perform different tests
Many research trials show poor validity (i.e. low likelihood ratios), and many show poor reliability (i.e. low kappa scores). A full discussion is outside the scope of this article. A useful text is Netter's Orthopaedic Clinical Examination. It was also comprehensively evaluated by the now quite old Australian Acute Musculoskeletal Pain Guidelines published in 2003.Australian Acute Musculoskeletal Pain Guidelines Group. (2003). Evidence-based management of acute musculoskeletal pain. Brisbane: Australian Academic Press. http://www.nhmrc.gov.au
For inspection there are no known relevant data as to it's reliability or validity.
For palpation in the spine, there is high reliability with kappa of 0.8-1.0 for tenderness around a painful shoulder or lower back, but the validity is unknown. The lumbar area has much lower reliability with a kappa of 0.11-0.38, and the validity is again unknown.
For range of motion testing, visual estimation has variable reliability, and goniometry doesn't provide any additional advantage. Inclinometry is inconsistently more reliable if done by trained practitioners. The validity of range of motion testing is largely unknown. One well known study from 1988 of a single clinician tested for passive and accessory intersegmental movements of the cervical spine and found 100% sensitivity and specificity for identifying painful zygapophyseal joints, but this small study hasn't been replicated elsewhere and the external validity is unknown.Jull, G., Bogduk, N.,&Marsland, A. (1988). The accuracy of manual diagnosis for cervical zygapophysial joint pain syndromes. The Medical Journal of Australia, 148, 233–236. Another larger study from 2007 showed high sensitivity but poor specificity for cervical zygapophyseal examination, leading to a positive likelihood ratio of not much more than 1.0.King, W., Lau, P., Lees, R., & Bogduk, N. (2007). The validity of manual examination in assessing patients with neck pain. The Spine Journal, 7, 22–26.
For tests of restraint, there is a large array of tests each with different reliabilities and validities. For reliability, it is likely that clinicians can be trained to achieve similar results. For validity there is inconsistent data. For the shoulder high sensitivity tests often have low specificity, and vice versa, leading to low positive likelihood ratios.Calis et al. (2000). Diagnostic values of clinical diagnostic tests in subacromial impingement syndrome. Annals of the Rheumatic Diseases, 59, 44–47.
A rational approach to examining a patient involves integrating clinical expertise with the best available external clinical evidence from systematic research.Sackett DL, Richardson WS, Rosenberg W, Haynes RB. Evidence-based  Medicine. How to Practice and Teach EBM. Churchill Livingstone, Edinburgh, 1997; p 2. Examination should increase the probability of one diagnosis, and help exclude other diagnoses.
== See Also ==
* Medical History
* Diagnosis
* A guide for virtual MSK examination in primary care: Murray T, Murray G, Murray J. Remote Musculoskeletal Assessment Framework: A Guide for Primary Care. Cureus. 2021 Jan 19;13(1):e12778. DOI PMID Full Text
== References ==
Category:Examination
Category:Clinical Reasoning