Clinical Roadmap · Shoulder
Shoulder Instability
Thinking Clinically · A guide for PT students and new grads
The patient is often an adolescent, young adult, or athlete who says the shoulder slipped, almost came out, or just feels loose, and who has stopped trusting a certain position. A shoulder can be hypermobile and completely asymptomatic, so laxity is a finding and instability is a symptom-producing problem. This roadmap shows how to recognize, confirm, differentiate, and treat shoulder instability, from traumatic anterior instability to multidirectional instability (MDI), and why the real target is control, not just mobility.
1
Recognize It
- Apprehension is often more prominent than pain, and a history of subluxation or dislocation strongly raises suspicion
- Traumatic anterior instability: a discrete event, often sports-related, with apprehension in abduction and external rotation (ABER). "It came out, and now I don't trust that position."
- MDI: usually atraumatic or gradual, with symptoms in several directions, generalized laxity, and poor dynamic control. "It's always been loose, and I can't control it."
- Symptoms show up with overhead activity, throwing, contact, pushing, and weight-bearing through the arm
- Neurologic symptoms can occur briefly after a dislocation, but should not be assumed to be part of chronic instability
- First impression: does the patient actually feel unstable, or am I simply seeing a mobile shoulder?
2
Confirm It
- History: ask about the first event, the number of episodes, whether it fully dislocated, subluxed, or reduced on its own, the direction, and which positions the patient now avoids. Risk factors include young age at first dislocation, contact or overhead sport, prior instability or surgery, hyperlaxity, and bone loss with recurrent anterior instability.
- Exam findings can look normal. AROM and PROM may be normal or excessive and strength may be near normal, because the problem is dynamic control, not peak force. A normal 5/5 MMT does not rule out instability.
- Instability tests: apprehension in ABER, then relocation, plus load-and-shift and the sulcus sign (test bilaterally, and repeat in ER). Add posterior tests (jerk, Kim) and the Beighton score when the history suggests it.
- Screen for competing findings: cuff tests (empty can/full can, ER lag, belly-press, lift-off), AC tests (palpation, cross-body adduction), and labral tests (O'Brien, crank, biceps load II). A positive labral test does not independently establish the cause of instability.
- No single cluster makes the diagnosis. A positive laxity test alone tells you the shoulder is mobile. Laxity plus familiar symptoms plus functional instability is much stronger evidence. Don't repeatedly force an apprehensive shoulder into the provocative position.
- Scapula and neuro: look for dyskinesis and poor control during elevation and closed-chain loading. After an acute dislocation, screen axillary nerve function (lateral shoulder sensation and deltoid activation).
3
Differentiate It
| Condition | What points toward it |
|---|---|
| Rotator cuff-related shoulder pain | Pain is the main symptom, PROM is preserved, symptoms follow resisted loading, there is a painful arc, and there is no history of slipping or dislocation |
| Labral pathology | Clicking or catching with instability, a traumatic mechanism, and symptoms with throwing or high-demand positions. It can coexist with instability |
| Adhesive capsulitis | PROM globally restricted with ER markedly limited. Stiffness dominates and the shoulder feels restricted, not unstable |
| Cervical radiculopathy | Neck symptoms, arm symptoms in a neurologic distribution, numbness or tingling, myotomal or reflex changes, and cervical movement that changes symptoms |
| Red flag / non-MSK | Deformity that doesn't resolve after an apparent dislocation, neurovascular changes, severe pain after significant trauma or concern for fracture, or progressive neurologic deficits |
Common Mistakes
- Calling every hypermobile shoulder "unstable," or assuming a positive sulcus sign automatically means symptomatic MDI.
- Treating all instability like anterior traumatic instability, or focusing on cuff strength while ignoring dynamic control.
- Returning an athlete to sport based on time alone, and progressing load faster than the patient can control the shoulder.
4
Treat It
- Educate first.
A mobile shoulder is not automatically a pathologic one. The goal is controlled exposure, not permanent avoidance, and psychological readiness matters, especially for athletes returning to sport. - Match activity to irritability.
When irritability is high or the event is recent, avoid positions that repeatedly reproduce apprehension, follow physician restrictions after reduction, and keep moving within a safe range. As it settles, reintroduce the provocative range gradually, add closed-chain and perturbation work, and then rebuild high-load, unpredictable, and sport- or work-specific demands. - Manual therapy is not the primary treatment.
Avoid aggressive glenohumeral mobilization to "loosen" an unstable shoulder. Use thoracic mobility or soft tissue work only when a specific restriction or guarding is present.
| Stage | Movement and motor control emphasis |
|---|---|
| Early | Joint position awareness, low-load co-contraction, controlled ROM, scapular control, and closed-chain stability (wall weight shifts, ball-on-wall circles, rhythmic stabilization). Short, frequent bouts of about 20 to 30 seconds, once or twice daily |
| Middle | Quadruped weight shifts, wall and incline push-ups, planks, band ER/IR, scaption, serratus work, and perturbation drills. Progress wall to floor, stable to unstable, predictable to unpredictable, slow to fast |
| Late | Reactive perturbations, medicine-ball catches, overhead stabilization, loaded carries, throwing progression, and sport-specific drills, with contact preparation when appropriate |
- Strengthening dosing:
Early cuff isometrics are submaximal 5 to 10 second holds, once or twice daily. For middle and later cuff and scapular work, use 2 to 3 sets of 8 to 15 repetitions, 2 to 3 days per week, at low to moderate effort with a few repetitions left in reserve. Closed-chain work uses a few 20 to 30 second holds, 2 to 3 days per week. - MDI starts with scapular control, low-load cuff activation, and closed-chain stability before overhead, reactive, sport-specific work.
Anterior instability follows BESS-style phases from protection and education through movement, strengthening, and return to sport. - Progress when pain is controlled, apprehension is decreasing, there are no new instability episodes, and confidence is improving.
Before return to sport, look for appropriate ROM, no meaningful apprehension in required positions, restored strength, good dynamic stability, tolerance of sport-specific loading, and psychological readiness. - Prognosis:
Recurrence risk after a first traumatic event is substantial in younger contact-sport athletes and depends on age, number of episodes, bone loss, and associated lesions. MDI often responds to consistent, well-progressed rehabilitation. - Reconsider the plan if instability episodes continue, the patient repeatedly subluxes or dislocates despite appropriate rehabilitation, apprehension stays severe, function keeps declining, significant bone loss is suspected, or neurologic symptoms persist.
Refer for orthopedic reassessment.
Key Takeaway
Don't diagnose instability because a shoulder is loose. Diagnose it when excessive mobility becomes symptomatic and the patient can't control the joint. For anterior instability, think traumatic event, recurrent apprehension, and ABER. For MDI, think atraumatic multidirectional symptoms, laxity, and poor dynamic control, and treat with stability, strength, proprioception, and functional control.
Want the full field note?
This Clinical Roadmap is a condensed teaser. The complete field note will be in the upcoming Thinking Clinically Shoulder Field Guide, which will include:
- The complete examination sequence, with every test, finding, and interpretation
- Two worked clinical reasoning cases with the answers explained
- Education scripts, irritability-based activity modification, and return-to-sport criteria
- Treatment frameworks, exercise progressions, and prognostic factors in full detail
Need exercise ideas?
Watch exercise demonstrations and clinical reasoning videos on the Thinking Clinically YouTube channel: youtube.com/@Thinking.Clinically
References
- Hurley ET, Matache BA, Wong I, et al.; Anterior Shoulder Instability International Consensus Group. Anterior Shoulder Instability Part I—Diagnosis, Nonoperative Management, and Bankart Repair—An International Consensus Statement. Arthroscopy. 2022;38(2):214-223.e7.
- Alentorn-Geli E, Ângelo AC, Brilakis E, et al. Age- and time-specific management of traumatic anterior shoulder instability: the 2024 ESSKA-ESA formal consensus. Part 1: History taking, physical exam and imaging studies. Knee Surg Sports Traumatol Arthrosc. 2026;34(4):1545-1555.
- Alentorn-Geli E, Brilakis E, Ângelo AC, et al. Age- and time-specific management of traumatic anterior shoulder instability: the 2024 ESSKA-ESA Formal Consensus. Part 2: Treatment and return to sports. Knee Surg Sports Traumatol Arthrosc. 2026;34(8):3040-3051.
- Wong C, Jaggi A, Kearney R, Gwilym S. British Elbow and Shoulder Society practice guidelines: Rehabilitation following traumatic anterior shoulder dislocation (post-operative and non-operative care). Shoulder Elbow. 2026;18(3):604-608.
- Watson L, Warby S, Balster S, Lenssen R, Pizzari T. The treatment of multidirectional instability of the shoulder with a rehabilitation program: Part 1. Shoulder Elbow. 2016;8(4):271-278.
Thinking Clinically · thinkingclinically.com · Educational use only; not a substitute for clinical judgment
