Shoulder Subluxation

Definition[edit | edit source]

Inferior-subluxation-post overdose.

Shoulder subluxation, a subset of shoulder instability, occurs when the shoulder joint partially dislocates. In this condition the humeral head slips out of the glenoid cavity as a result of weakness of rotator cuff or looseness of the glenohumeral ligaments.[1]

Epidemiology[edit | edit source]

Studies are limited that investigate the epidemiology of shoulder subluxation, with most studies focus more on shoulder dislocations.[1]

  • In a study on shoulder subluxations, 45.5% experienced the first subluxation event, while the remaining 54.5% had recurrent shoulder subluxation.[1]
  • Shoulder subluxations frequently occur in people with hemiplegic stroke or with a paralysed upper limb (see Hemiplegic Shoulder Subluxation). The reported incidence varies greatly from 17% to 81% [2] [3]

Etiology[edit | edit source]

Causes can be classified as traumatic, non-traumatic or neuromuscular:

  1. Traumatic cause: more frequent in active young individuals. Prevalent in for example: boxers,; non-contact sport with repetitive shoulder movements; a hand in the outstretched position.
  2. Non-traumatic cause: multifactorial. For example: patients may have suboptimal shoulder muscle control or tendon/ligament injury in the rotator cuff interval
  3. Neuromuscular causes: for example stroke, cerebral palsy, and brachial plexus injury.[1]

Watch this 4 minute video for an introduction to shoulder sunluxation.


Characteristics/clinical presentation[edit | edit source]

The main problem with shoulder subluxation is the instability of the glenohumeral joint. Common symptoms of chronic shoulder instability include:

  • Recurrent shoulder dislocations
  • Periodic instances of the shoulder giving out
  • A persistent feeling of the shoulder being loose or slipping in and out of the joint.
  • Pain [5]

Research by Basmajian determined that the supraspinatus and in minor ways also the posterior fibres of the deltoid muscle play a key role in maintaining glenohumeral alignment[6]. Chaco and Wolf did confirm this in their study, which said that the supraspinatus is very important in preventing the downward subluxation of the humerus.

Subluxation occurs with the shoulder in abduction and external rotation.

Other research shows that the most important ligamentous structure to maintain correct shoulder position and also to prevent shoulder subluxation is the inferior glenohumeral ligament.This ligament is most important during external rotation and abduction during the cocking face of the throwing motion.

Shoulder subluxation can lead to soft tissue damage as traction damage can occur due to gravitational pull forces and poor protection is offered by a weak shoulder. It is usually quite painful, and there might be a partial numbness of the shoulder, arm, and hand.

Differential Diagnosis[edit | edit source]

  • Acromioclaviculair joint injuries: common and often seen after bicycle wrecks, contact sports, and car accidents. The acromioclavicular joint is located at the top of the shoulder where the acromion process and the clavicle meet to form a joint. Several ligaments surround this joint, and depending on the severity of the injury, a person may tear one or all of the ligaments. Torn ligaments lead to acromioclavicular joint sprains and separations.
  • Bicep tendinopathy, is an inflammatory process of the long head of the biceps tendon and is a common cause of shoulder pain due to its position and function[7].
  • Clavicular injuries: Although clavicle fractures are common and usually heal regardless of the selected treatment, complications are possible, warranting careful attention to these injuries. [8][9]
  • Rotator cuff injuries are a common cause of shoulder pain in people of all age groups. They represent a spectrum of disease, ranging from acute reversible tendinitis to massive tears involving the supraspinatus, infraspinatus, and subscapularis. Diagnosis is usually made through detailed history, physical examination, and often, imaging studies.
  • Shoulder dislocations may occur from a traumatic injury or from loose capsular ligaments. Different conditions may affect the stabilising structures of the shoulder and, thus, negatively affect patients with shoulder dislocations.
  • Swimmer's shoulder is the term used to describe the problem of shoulder pain in the competitive swimmer. Swimming is an unusual sport in that the shoulders and upper extremities are used for locomotion, while at the same time requiring above average shoulder flexibility and range of motion (ROM) for maximal efficiency. This is often associated with an undesirable increase in joint laxity[10].

Diagnostic Procedures[edit | edit source]

Patients with shoulder subluxations commonly present with:

  • Pain in the shoulder region
  • Loss of range of movement 
  • The palpable gap between acromion and humeral head (this can be informally measured in finger-widths)

Functional testing

  • The subluxation test is positive = resistance is given when the patient brings arm in throwing stance, in internal rotation direction.
  • Pain in the ventral capsule indicates a frontal capsule lesion.
  • Pressure during resistance test on the dorsal part of the humerus can provoke ventral gliding. The result is sudden pain in the
  • shoulder and in a number of cases there is a subluxation to the front. This test can be conducted in different degrees of abduction and with or without the support of the upper arm.

Radiographic measurements are considered to be the most accurate way of evaluating the degree of subluxation[11]

Outcome Measures[edit | edit source]

Examination[edit | edit source]

First, the examiner should ask the patient about the history of the reason he subluxated his arm. Then he can perform an inspection, when he does he should make sure that he can have a visual on both shoulders at the same time to see the difference.
After this you could use different tests to test whether the patient had a subluxation of the shoulder:

Physical Therapy Management[edit | edit source]

Traumatic and Non-Traumatic Patient (see also detailed information here Shoulder Instability)

Rotator cuff exercise

Prevention of reccurance:
Strengthening exercises to re-establish the strength of the rotator cuff muscles is recommended. 
Initial physical therapy interventions may include:

Late stages of rehabilitation of rotator cuff injury include progressive resistive strengthening, proprioception and sport-specific exercises.

This 2 minute video shows treating subluxation of the shoulder, use a sling and an exercise ball (to strengthen the shoulder) muscles.


For Hemiplegic Patient see Hemiplegic Shoulder Subluxation

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 Vitoonpong T, Chang KV. Shoulder Subluxation. InStatPearls [Internet] 2020 Aug 29. StatPearls Publishing.Available: (accessed 8.1.2023)
  2. Huang SW, Liu SY, Tang HW, Wei TS, Wang WT, Yang CP. Relationship between severity of shoulder subluxation and soft-tissue injury in hemiplegic stroke patients. J Rehabil Med. 2012 Sep;44(9):733-9.
  3. Hartwig M, Gelbrich G, Griewing B. Functional orthosis in shoulder joint subluxation after ischaemic brain stroke to avoid post-hemiplegic shoulder-hand syndrome: a randomized clinical trial. Clin Rehabil. 2012 Sep;26(9):807-16.
  4. Dr. David Geier. Shoulder subluxation. Available from: [last accessed 25/4/2022]
  5. Orthoinfo Chronic Shoulder Instability Available: (accessed 8.1.2023)
  6. Reed D, Cathers I, Halaki M, Ginn K. Does supraspinatus initiate shoulder abduction?. Journal of Electromyography and Kinesiology. 2013 Apr 1;23(2):425-9.
  7. Raney EB, Thankam FG, Dilisio MF, Agrawal DK. Pain and the pathogenesis of biceps tendinopathy. American journal of translational research. 2017;9(6):2668.
  8. O’Neill BJ, Hirpara KM, O’Briain D, McGarr C, Kaar TK. Clavicle fractures: a comparison of five classification systems and their relationship to treatment outcomes. International orthopaedics. 2011 Jun;35(6):909-14.
  9. Lasanianos NG, Panteli M. Clavicle fractures. InTrauma and Orthopaedic Classifications 2015 (pp. 11-15). Springer, London.
  10. De Martino I, Rodeo SA. The swimmer’s shoulder: multi-directional instability. Current reviews in musculoskeletal medicine. 2018 Jun;11(2):167-71.
  11. Paci M, Nannetti L, Rinaldi LA. Glenohumeral subluxation in hemiplegia: An overview. J Rehabil Res Dev. 2005 Jul-Aug;42(4):557-68.
  12. The Physio Channel. The Load & Shift Test . Available from: [last accessed 27/4/2022]
  13. ehowhealth. Physical Therapy Treatments : How to Treat Subluxation . Available from: [last accessed 25/4/2022]