The Shoulder - Therapeutic Exercises

Anatomy and Kinematics of the Shoulder Joints

Glenohumeral (GH) Joint (Synovial): * Defined as a Triaxial joint with a lax capsule, especially in the inferior aspect. * Supported by the Rotator Cuff (RC) muscles, coracohumeral ligaments, and the labrum. * Oriented to face laterally, anteriorly, and slightly upward.
Acromioclavicular (AC) Joint: * A Triaxial joint characterized by a weak capsule. * Reinforced by the superior and inferior AC ligaments, and the strong coracoclavicular ligament. * Notably, no muscles cross this joint directly.
Sternoclavicular (SC) Joint: * A Triaxial, saddle-type joint containing a disk. * Supported by the anterior and posterior SC ligaments, as well as costoclavicular ligaments.
Scapulothoracic Functional Joint: * Stabilized through a balance of forces intended to maintain proper posture. * Faulty Posture Indicators: * Decreased posterior tilting and external rotation (ER) during elevation of the arm. * Decreased flexibility in the pectoralis minor, levator scapulae, and scalenes. * Decreased strength in the serratus anterior and trapezius muscles.
Scapulohumeral Rhythm: * Setting Phase: Occurs during the first $0-30^{\circ}$ of abduction or $0-60^{\circ}$ of flexion, where motion is primarily GH joint-driven. * Midrange: Transitions to a $1:1$ ratio. * Late Range: Returns to being primarily GH joint motion. * Commonly Accepted Ratio: A overall $2:1$ ratio of GH motion to scapular motion ( $2^{\circ}$ of GH motion for every $1^{\circ}$ of scapular motion). * Function: This rhythm maintains the optimal length-tension relationship for muscles and maximizes bone congruency.
Scaption: * Defined as the plane of the scapula, situated $30^{\circ}$ anterior to the frontal plane. * Offers less tension on the capsule and allows for greater elevation compared to pure sagittal or frontal planes. * Often used clinically as a less painful position for Range of Motion (ROM) work.

Referred Pain and Nerve Disorders

Dermatome and Organ-Based Referred Pain: * Dermatome C4: Distributed over the trapezius muscle to the tip of the shoulder. * Dermatome C5: Distributed over the deltoid region and the lateral arm. * Diaphragm: Pain referred into the upper trapezius. * Heart: Pain referred to the axilla or the left pectoralis region. * Gallbladder: Pain referred to the tip of the shoulder and the posterior scapula.
Peripheral Nerve Disorders: * Brachial Plexus (Thoracic Outlet): Compression can occur in the scalene triangle, the costoclavicular space, under the coracoid process, or under the pectoralis minor. * Suprascapular Nerve: Compression typically occurs in the suprascapular notch, often due to carrying heavy bags or purses. * Radial Nerve: Compression occurs in the axilla, frequently associated with leaning on crutches.

Joint Hypomobility: Non-operative Management

Glenohumeral Joint Arthritis: * Acute Phase: * Symptoms: Limited ROM due to pain and muscle guarding (specifically ER and Abduction). * Radiation: Pain may extend past the elbow and disrupt sleep. * Clinical signs: No visible swelling; tenderness common below the acromion between the middle and posterior deltoids. * Subacute Phase: * Symptoms: Capsular tightness with ER and abduction most limited; internal rotation (IR) and flexion are least limited. * Clinical signs: Pain at end range; Passive Range of Motion (PROM) reveals limited joint play. * Chronic Phase: * Symptoms: Persistent capsular restrictions and pain localized to the deltoid region. * Activity limitations: Inability to reach overhead, outward, or behind the back.
Idiopathic Frozen Shoulder (Adhesive Capsulitis): * Characterized by dense adhesions and capsular restrictions, particularly in the inferior fold, rather than changes to bone or cartilage. * Classifications: * Primary: Insidious onset with no known cause. * Secondary: Follows a specific pathology. * Demographics: Most common in women, ages $40-60$ , and frequently seen in the diabetic population. * Stages of Frozen Shoulder: * Stage 1: Gradual onset of pain increasing with movement; night pain; loss of ER with intact RC strength. Duration: $< 3$ months. * Stage 2 (Freezing): Persistent and intense pain; ROM is limited in all directions. Duration: $3-9$ months. * Stage 3 (Frozen): Pain only with movement; significant adhesions; global ROM limits with substitute scapular motions; atrophy of RC, deltoid, biceps, and triceps. Duration: $9-15$ months. * Stage 4 (Thawing): Minimal pain and no synovitis; significant capsular restrictions persist, but ROM may gradually improve. Duration: $15-24$ months. Full ROM may never be regained.

Management Phases for Hypomobility

Protection (Acute) Phase: * Goals: Patient education; control pain, edema (rarely seen), and muscle guarding. * Interventions: PROM, manual joint mobilizations (Grades I and II), inferior and posterior motions. * Soft Tissue: Work on cervical paraspinals and periscapular muscles (stretching upper traps and levator scapulae to avoid hiking). * Maintenance: C-spine, elbow, wrist, and hand ROM; ball squeezes. If hand edema exists, elevate the limb. * Specific: Pendulum (Codman’s) exercises—using body weight for passive swing; gentle muscle setting/isometrics.
Controlled Motion (Subacute) Phase: * Goals: Progressively increase ROM to the point of pain; inhibit muscle spasms; correct posture. * Interventions: Joint mobilizations (Grades III and IV); self-mobilization techniques; manual/self-stretching; joint oscillations. * Strengthening: Protected weight bearing; RC strengthening in IR/ER; scapular squeezes; foam roller stretches. * Techniques: Sustained caudal glide; Mobilization with Movement (MWM).
Return to Function (Chronic) Phase: * Goals: Increase flexibility and strength; advance to functional activities. * Interventions: Self-stretching, vigorous manual stretching if restrictions persist, and grade-appropriate joint mobilization.
Postmanipulation under Anesthesia (MUA): * Treated as an acute lesion due to inflammation. * Rehab: Mobility initiated in recovery room; focus on IR/ER with abduction $< 90^{\circ}$ . * Clinical frequency: Typically $5$ times per week for $2$ weeks, then reduced to $2-3$ times per week.

AC and SC Joint Overuse and Trauma

Overuse Syndromes: Caused by repetitive stresses (e.g., grinding, packing, construction) or diagonal extension (e.g., volleyball serving).
Subluxation/Dislocation (Separated Shoulder): * Mechanism of Injury (MOI): Falling on the shoulder or a Fall On Outstretched Hand (FOOSH). * AC Joint Specifics: Often displaces posteriorly and superiorly; ligaments may rupture. Permanent hypermobility is common due to lack of muscle support. * Hypomobility: May result from osteoarthritis (OA) and contribute to Thoracic Outlet Syndrome (TOS).
Clinical Management: * Impairments: Local pain at end range elevation, flexion, IR, and horizontal add/abd. * Non-operative: Minimize joint loading with a sling; use cross-friction massage; maintain GH motion; strengthen shoulder complex, trunk, and legs.

Glenohumeral Arthroplasty

Types: * Total Shoulder Arthroplasty (TSA): Replacement of both glenoid and humeral surfaces. * Hemiarthroplasty: Replacement of only the humeral head. * Reverse Total Shoulder Arthroplasty (rTSA): Used when the RC is deficient or for instability. Results in loss of functional flexion, ABD, and ER.
Indications: Incapacitating pain from joint destruction; loss of mobility/stability; inability to perform functional tasks.
Specific Post-Op Phases: * Phase 1 (TSA): Weeks $0-4$ . (rTSA): Weeks $0-6$ . * Phase 2 (TSA): Weeks $4-12$ . (rTSA): Weeks $6-12$ or $16$ . * Phase 3 (TSA): Weeks $12+$ . (rTSA): Weeks $12+$ or $16+$ .
Progression Criteria (Maximum to Moderate Protection): * TSA: $90^{\circ}$ passive flexion, $45^{\circ}$ ER, $70^{\circ}$ IR in scaption; pain-free waist-level ADLs. * rTSA: Tolerate AAROM and isometrically activate deltoid (e.g., doorway punches).
Progression Criteria (Moderate to Minimum Protection): * Full PROM; ER $> 60^{\circ}$ , IR $> 70^{\circ}$ ; Active flex (scaption) $100-120^{\circ}$ ; $4/5$ strength in RC/deltoid.

Rotator Cuff Disease

Acromion Classifications (Shape): * Type I: Flat. * Type II: Curved (Associated with impingement). * Type III: Hooked (Associated with impingement).
Rotator Cuff Anatomy and Function: * Composed of Subscapularis (IR), Infraspinatus (ER), Supraspinatus (Depressor/Elevation), and Teres Minor (ER). * Function: Depresses and stabilizes the humeral head.
Subacromial Decompression: Indications include Neer Stage II impingement (tendonitis/bursitis/fibrosis) in patients aged $25-40$ . ROM criteria for progression includes nearly full PROM and $3/5$ to $4/5$ strength.

Rotator Cuff Repair and Instability

Surgical Approaches: * Arthroscopic: Small incisions (most common). * Mini-open: Deltoid-splitting approach. * Traditional open: Detachment/reattachment of the deltoid.
Immobilization by Tear Size: * Small: Sling $1-2$ weeks. * Medium to Large: Sling/Abduction pillow $3-6$ weeks. * Massive: Sling/Abduction pillow $4-8$ weeks.
Shoulder Instability Classification: * Anterior: Most common; occurs with abduction/ER. May involve a Bankhart Lesion (Glenoid rim fracture and labrum damage). * Posterior: Occurs with flexion/adduction/IR or FOOSH. * Inferior: Linked to RC weakness, common in hemiplegia.
SLAP Lesion Repair Precautions: * Limit flexion to $60^{\circ}$ for first $2$ weeks and $90^{\circ}$ at weeks $3-4$ . * Avoid biceps tension for $4-6$ weeks. * No weighted carrying for $8-12$ weeks.
Bankhart Repair Precautions: * Limit ER, horizontal ABD, and extension for first $6$ weeks. * No vigorous stretching for end-range ER for $8-12$ weeks.