Low Back Pain

The rotator cuff consists of:

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

The cuff centres the humeral head against the glenoid while allowing shoulder elevation and rotation.

Tears may be:

• Traumatic
• Degenerative
• Partial thickness
• Full thickness
• Repairable
• Irreparable

The supraspinatus is most commonly involved.

A practical full thickness tear size description is:

• Small: below 1 cm
• Medium: 1 to 3 cm
• Large: 3 to 5 cm
• Massive: greater than 5 cm or involving at least two tendons

Tear size alone does not define reparability.

Reparability also depends on:

• Retraction
• Muscle atrophy
• Fatty infiltration
• Tendon quality
• Chronicity
• Superior humeral migration

Pain is commonly:

• Anterolateral
• Worse with overhead activity
• Worse at night
• Worse when lying on the affected side

Patients may develop:

• Weakness
• Difficulty elevating the arm
• Loss of external rotation
• Pseudoparalysis with massive tears

A traumatic full thickness tear can present as sudden inability to elevate an arm that previously functioned normally.

Examination

Assess active and passive range separately.

Preserved passive motion with major loss of active elevation suggests rotator cuff dysfunction rather than adhesive capsulitis.

Useful tests include:

Supraspinatus

• Jobe empty can
• Full can

Infraspinatus

• Resisted external rotation
• External rotation lag

Subscapularis

• Lift off
• Belly press
• Bear hug

A positive drop arm test suggests a substantial supraspinatus tear but is insensitive for smaller tears.

Plain radiographs: assess:

• Acromial morphology
• Glenohumeral arthritis
• Superior humeral migration
• Greater tuberosity changes
• Acromiohumeral interval

Ultrasound: highly effective for experienced operators and useful for dynamic assessment.

MRI: investigation of choice when surgical planning is likely.

Define:

• Tendons involved
• Tear size
• Retraction
• Muscle atrophy
• Fatty infiltration
• Biceps pathology
• Labral and cartilage disease

A chronic tear with severe muscle atrophy and advanced fatty infiltration may no longer be anatomically repairable even if the tendon edge can be identified.

Initial nonoperative treatment

Most degenerative tears can initially undergo:

• Activity modification
• Structured physiotherapy
• Analgesia
• Selected injection therapy

Physiotherapy should emphasise:

• Rotator cuff strengthening
• Scapular stabilisation
• Posterior capsular mobility where restricted
• Restoration of shoulder mechanics

Both physical therapy and surgery produce clinically meaningful improvement for many symptomatic small and medium full thickness tears. However, tears managed nonoperatively may enlarge and develop progressive muscle atrophy and fatty infiltration over subsequent years.

Analgesia

A practical regimen is:

Paracetamol 1 g orally every 6 to 8 hours as required, maximum 4 g daily in an adult without significant hepatic risk.

An NSAID may be added when renal, gastrointestinal and cardiovascular risk permits.

Corticosteroid injection

A single subacromial corticosteroid injection can provide short term improvement in pain and function.

Repeated injections should be avoided when surgical repair may ultimately be required because corticosteroid exposure can adversely affect tendon tissue and healing, particularly when performed close to surgery.

Partial thickness tear

A tear involving less than approximately 50% of tendon thickness is generally treated initially with rehabilitation.

Persistent symptoms can undergo:

• Arthroscopic debridement
• Treatment of associated pathology

A high grade partial tear involving more than approximately 50% of tendon thickness that remains symptomatic despite nonoperative treatment generally warrants repair rather than debridement alone.

Acute traumatic full thickness tear

A young or active patient with:

• Acute traumatic tear
• New objective weakness
• Previously normal shoulder

should receive early surgical assessment.

Repair before major retraction and muscle degeneration develops is generally preferable when surgery is indicated.

Full thickness degenerative tear

Operate when there is:

• Persistent pain despite appropriate rehabilitation
• Function limiting weakness
• Progressive tear
• High functional demand
• Repairable anatomy
• Patient preference after informed discussion

Do not operate solely because MRI shows a tear in an asymptomatic shoulder.

Arthroscopic repair

The objective is secure tendon to bone healing at the greater tuberosity.

Steps include:

• Mobilise tendon without excessive tension
• Prepare the footprint
• Repair tendon with suture anchors
• Treat significant associated biceps pathology where required
• Preserve viable tendon tissue

Single versus double row

For many small to medium tears, both single and double row fixation produce good clinical outcomes.

For tears above approximately 3 cm, double row constructs can reduce overall structural failure and may improve outcomes compared with simple single row repair.

The best repair is a low tension construct with adequate tendon mobilisation and good biological contact. A technically dense double row repair performed under excessive tension is not advantageous.

Biological augmentation

Routine platelet derived augmentation does not meaningfully improve patient reported outcomes.

Liquid PRP may reduce some structural retears, but the evidence does not justify routine use for every repair.

Massive repairable tear

Repair as much of the functional force couple as possible.

Restoring:

• Subscapularis anteriorly
• Infraspinatus and teres minor posteriorly

can restore meaningful shoulder function even when complete anatomical footprint coverage is difficult.

Options include:

• Complete repair
• Partial repair
• Margin convergence
• Augmentation in selected cases

Massive irreparable tear without arthritis

Treatment depends on:

• Age
• Pseudoparalysis
• Which tendons are deficient
• Subscapularis function
• Glenohumeral cartilage

Options include:

Superior capsular reconstruction

Useful in selected younger patients with irreparable superior cuff deficiency and preserved joint surfaces.

Tendon transfer

For irreparable posterosuperior deficiency:

• Latissimus dorsi transfer
• Lower trapezius transfer

can restore external rotation in selected younger patients.

For irreparable subscapularis deficiency, pectoralis major or other transfer procedures may be considered.

Reverse shoulder arthroplasty

Particularly useful with:

• Massive irreparable cuff tear
• Cuff tear arthropathy
• Persistent pseudoparalysis
• Older lower demand patient
• Failed previous cuff reconstruction

The reverse prosthesis allows the deltoid to elevate the arm despite absent rotator cuff function.

Avoid using reverse arthroplasty simply because an MRI calls a tear massive in a young patient with preserved function and no arthritis.

Postoperative rehabilitation

Healing is biological and takes months.

A typical programme progresses through:

• Sling protection
• Passive movement
• Assisted movement
• Active movement
• Strengthening

Larger tears require greater initial protection.

Do not begin aggressive resisted cuff loading during the early tendon to bone healing phase.

Retear

Structural retear is more common with:

• Large initial tear
• Older age
• Poor tendon quality
• Advanced fatty infiltration
• Smoking
• Diabetes
• Inadequate healing biology

A retear on MRI does not automatically require revision if function and pain remain acceptable.

Symptomatic repair failure requires reassessment of:

• Tendon reparability
• Muscle quality
• Arthritis
• Patient demand

before choosing revision repair, reconstruction, tendon transfer or reverse arthroplasty.