Clinical Notes : Orthopedics and Trauma

78. Shoulder instability

If the presenting shoulder pain is not referred from the neck then consider :

  1. Frozen shoulder

  2. Acromioclavicular joint pain

    • AC disruption

    • AC osteoarthritis

  3. Rotator cuff pain

    • Impingement

    • Tear

    • Calcific tendonitis

  4. Shoulder instability

  5. Glenohumeral arthritis

Urgent referral if shoulder pain in the presence of :

  • History of trauma with acute pain & weakness

    • AC joint tear or displacement

    • Rotator cuff tear

  • History of trauma or epileptic fit leading to loss of rotation

    • SLAP tear

  • History of instability or subluxation

    • Dislocation

  • Mass/swelling/erythema

    • Infective process


Superior Labrum Anterior and Superior (SLAP) tear


Etiology :

Injuries to the superior labrum can be caused by acute trauma or by repetitive shoulder motion. An acute SLAP injury may result from:

  • A motor vehicle accident

  • A fall onto an outstretched arm

  • Forceful pulling on the arm, such as when trying to catch a heavy object

  • Rapid or forceful movement of the arm when it is above the level of the shoulder

  • Shoulder dislocation


People who participate in repetitive overhead sports, such as throwing athletes or weightlifters, can experience labrum tears as a result of repeated shoulder motion.


Many SLAP tears, however, are the result of a wearing down of the labrum that occurs slowly over time.

In patients over 40 years of age, tearing or fraying of the superior labrum can be seen as a normal process of aging.

This differs from an acute injury in a person under the age of 40.

Diagnosis :

The common symptoms of a SLAP tear are similar to many other shoulder problems. They include:

  • A sensation of locking, popping, catching, or grinding

  • Pain with movement of the shoulder or with holding the shoulder in specific positions

  • Pain with lifting objects, especially overhead

  • Decrease in shoulder strength

  • A feeling that the shoulder is going to "pop out of joint"

  • Decreased range of motion

  • Pitchers may notice a decrease in their throw velocity, or the feeling of having a "dead arm" after pitching


​​Video : Examination to detect SLAP tear  (4:55)



  • x-ray to detect arthritis, bone spurs or other acromion abnormality

  • MRI with intrarticular dye

  MRI  healthy shoulder

MRI tear in the labrum

Management :

Refer all suspected SLAP tears to secondary care for

  • NSAIDs

  • Stretching and strengthening excercises

  • Surgical repair


​​Video : SLAP Tear Stretches & Exercises  (9:25)


Shoulder dislocation (chronic shoulder instability)


Partial dislocation

  • where  the head of humerus is just partially out of the socket (subluxation)

Complete dislocation

  • where the head of humerus comes all the way out of the socket

Once the ligaments, tendons, and muscles around the shoulder become loose or torn, dislocations can occur repeatedly.

Chronic shoulder instability is the persistent inability of these tissues to keep the arm centred in the shoulder socket.

Etiology :

  • Shoulder dislocation

    • following acute injury to the glenoid and anterior ligaments of shoulder

  • Repetitive strain

    • loose shoulder ligaments

      • normal individual's anatomy

      • repetitive overhead motion (e.g. swimming, tennis, volleyball, certain jobs)

  • Multidirectional instability

    • Naturally loose ligaments throughout body or "double jointed" leading to repetitive dislocation out the front, back and/or bottom of the shoulder

Diagnosis :

Common symptoms of chronic shoulder instability include:

  • Pain caused by shoulder injury

  • Repeated shoulder dislocations

  • Repeated instances of the shoulder giving out

  • A persistent sensation of the shoulder feeling loose, slipping in and out of the joint, or just "hanging there"

  • A numb spot, lateral and superior arm, when nerves are compromised


​​Video : Examination to detect shoulder instability  (4:50)


Management :

Refer all acute dislocations, chronic instability and subluxations to secondary care for

  • NSAIDs

  • Stretching and strengthening excercises

  • Activity modification

  • Surgical repair

    • arthroscopic (Bankart repair)

    • open ( Latarjet repair)

Phases of Rehabilitation for Shoulder Instability

  • Phase I

    • Rest and immobilization

    • Pain control with nonsteroidal anti-inflammatory drugs and ice applied to the shoulder

  • Phase II

    • Isometric strengthening

    • Isotonic strengthening

    • Begin exercises with shoulder in adducted, forward-flexed position, progressing to abducted position

  • Phase III

    • Endurance building along with strengthening exercises

    • Goal: the patient reaches 90% strength in the injured shoulder compared with the uninjured shoulder

  • Phase IV

    • Increase activity to sport- or job-specific activities


​​Video : Shoulder instability Exercises  (4:10)


The Recognition and treatment of superior labral (SLAP) lesions in the overhead athlete.

Kevin E. Wilk, Leonard C. Macrina, E. Lyle Cain, Jeffrey R. Dugas, and James R. Andrews.

Int J Sports Phys Ther. 2013 Oct; 8(5): 579–600.


Superior labral tears of the shoulder: pathogenesis, evaluation and treatment.

Keener JD, Brophy RH.

J Am Acad Orthop Surg. 2009;17:627-637.


Superior labrum anterior and posterior lesions of the shoulder: incidence rates, complications, and outcomes as reported by American Board of Orthopedic Surgery Part II candidates.

Weber SC, Martin DF, Seiler JG3rd, Harrast JJ.

Am J Sports Med. 2012;40:1538-1543



Shoulder instability. Diagnosis and management.

Callanan M, Tzannes A, Hayes K, Paxinos A, Walton J, Murrell GA.

Aust Fam Physician. 2001 Jul;30(7):655-61.



Risk factors which predispose first-time traumatic anterior shoulder dislocations to recurrent instability in adults: a systematic review and meta-analysis.

Olds M, Ellis R, Donaldson K, Parmar P, Kersten P.

Br J Sports Med. 2015 Jul. 49 (14):913-22.



Evidence-based conservative rehabilitation for posterior glenohumeral instability: A systematic review.

McIntyre K, Belanger A, Dhir J, et al.

Phys Ther Sport. 2016 Jun 7. 22:94-100.


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