Rotator Cuff Repair

Rotator cuff repair — the surgical reattachment of torn rotator cuff tendons to the proximal humeral footprint — is one of the most commonly performed orthopaedic procedures. The rotator cuff consists of four muscles and their tendons: supraspinatus (abduction and internal rotation), infraspinatus (external rotation), teres minor (external rotation), and subscapularis (internal rotation and stabilisation of the long head of biceps). The supraspinatus tendon is most commonly torn, followed by infraspinatus. Understanding the anatomy, the factors affecting healing and repair integrity, the surgical techniques available, and the outcomes data is essential for informed surgical decision-making.

• Rotator cuff anatomy relevant to repair: the supraspinatus inserts via a broad footprint on the greater tuberosity (the `critical zone` — the most avascular region of the supraspinatus tendon, 5–10 mm from its insertion — is the most common site of tearing); the footprint of the supraspinatus is trapezoidal, approximately 25 mm mediolaterally and 12–16 mm anteroposteriorly; repair aims to restore the native footprint contact area; the infraspinatus footprint lies posterior and inferior to the supraspinatus on the greater tuberosity; the subscapularis inserts on the lesser tuberosity — subscapularis tears are often missed clinically and on MRI (bear-hug test, belly-press test, and lift-off test are specific for subscapularis); the long head of biceps tendon runs within the bicipital groove beneath the transverse humeral ligament and is commonly associated with rotator cuff tears (tenodesis or tenotomy is often performed as an adjunct)
• Tear classification by size (Ellman): small (<1 cm), medium (1–3 cm), large (3–5 cm), massive (≥5 cm or involving two or more tendons); massive tears may be accompanied by fatty infiltration of the muscle belly (Goutallier classification 0–IV on CT/MRI — Grades III–IV indicate poor muscle quality and predict worse repair outcomes) and muscle atrophy/retraction
• Goutallier classification for fatty infiltration: Grade 0 — no fat (normal); Grade I — some fat streaks; Grade II — less fat than muscle; Grade III — equal fat and muscle; Grade IV — more fat than muscle; Grades III and IV indicate irreversible muscle degeneration and are associated with high re-tear rates after repair (the muscle cannot generate adequate tension even if the tendon is surgically attached); Goutallier Grade III–IV = relative contraindication to repair of that specific tendon; consider irreparable tear strategies instead (partial repair, tendon transfer, arthroplasty)

• Acute full-thickness tears: traumatic full-thickness supraspinatus (or other cuff tendon) tear in an otherwise healthy young-to-middle-aged patient — early repair (within 6 weeks of injury) recommended before tendon retraction and muscle degeneration progress; acute tears in high-demand workers or athletes; acute subscapularis tears; acute traumatic tears in patients >60 years — less clear, but surgical repair still appropriate in active patients with good bone and muscle quality
• Chronic full-thickness tears with symptoms: failed conservative management (>3–6 months of physiotherapy, anti-inflammatories, and subacromial injections); persistent pain, weakness, and functional limitation; full-thickness tear with retraction but still deemed repairable on pre-operative MRI (Goutallier 0–II; adequate tendon tissue for repair); patient age, activity level, and tissue quality are key decision factors
• Predictors of repair success: smaller tear size; acute tear (less muscle degeneration); younger patient age; Goutallier Grade 0–I (healthy muscle); minimal tendon retraction; no pseudoparalysis (inability to actively elevate the arm — indicates massive tear with absent deltoid compensation); normal deltoid function; absence of OA (cuff tear arthropathy — Hamada classification — is a relative contraindication to isolated repair; these patients may need RSA); good bone quality; surgeon experience and technique
• Contraindications / relative contraindications: Goutallier III–IV (irreversible fatty infiltration); massive irreparable tear with cuff tear arthropathy (Hamada Grade III–IV/V — Hamada classification: Grade I = acromiohumeral interval AHI ≥6 mm, no acetabularisation; Grade II = AHI 5 mm; Grade III = AHI ≤4 mm + acetabularisation; Grade IV = complete erosion of humeral head; Grade V = glenohumeral OA); pseudoparalysis in elderly patient — reverse shoulder arthroplasty (RSA) may be the better option

• Single-row vs double-row repair: single-row repair — suture anchors placed in a single row at the lateral greater tuberosity articular margin; re-establishes medial-to-lateral tension; simpler technique; re-tear rates 20–40% at 2 years; double-row repair — a medial row of anchors placed at the medial aspect of the footprint (at the articular margin) and a lateral row placed at the lateral greater tuberosity; the medial row sutures are passed through the tendon and tied; the lateral row anchors lock the tendon against the footprint via a `suture-bridge` or `knotless` configuration; restores the native footprint contact area more completely; biomechanically superior to single-row in laboratory studies (greater footprint contact area, lower interface motion); clinical superiority is demonstrated in meta-analyses for larger tears (>3 cm) — significantly lower structural re-tear rates with double-row; for small-to-medium tears, single-row and double-row have similar outcomes
• Suture bridge (transosseous-equivalent) technique: a specific double-row configuration where the medial row suture limbs are brought laterally under the tendon and locked into lateral knotless anchors; this creates a bridge of suture beneath which the tendon is compressed against the footprint; provides maximum footprint restoration and compression; the most commonly used double-row technique for larger tears
• Arthroscopic vs open vs mini-open repair: arthroscopic repair — the current gold standard approach for most tears; all work performed arthroscopically through portals; advantages — minimally invasive, excellent visualisation of the entire cuff and joint, precise anchor placement, low wound complication rate; disadvantages — technically demanding, steep learning curve, longer operative time; mini-open repair — a small (3–5 cm) deltoid-splitting incision combined with arthroscopic subacromial decompression; direct visualisation of tear; intermediate complexity; open repair — direct approach via deltoid takedown; now reserved for massive irreparable tears requiring tendon transfers or complex reconstructions; higher morbidity from deltoid detachment
• Subacromial decompression (acromioplasty): removal of the anterior acromial spur and inferior acromion to reduce subacromial impingement; routinely performed with most rotator cuff repairs to increase subacromial space; landmark RCTs (CSAW trial — Beard et al., BMJ 2018; FIMPACT trial) showed acromioplasty alone or sham surgery provided no benefit over physiotherapy for subacromial impingement without a full-thickness cuff tear; decompression remains appropriate as part of the surgical field preparation when undertaking rotator cuff repair
• Augmentation with biologic scaffolds (patches): for large and massive tears with poor tissue quality, an acellular dermal allograft or xenograft patch can be used to augment (not replace) the repair — sewn onto the superficial surface of the repaired tendon to reinforce it; collagen-based patches (GraftJacket, Arthroflex, OrthoAdapt); evidence for clinical benefit is emerging but limited; biological augmentation (PRP — platelet-rich plasma, injected at the repair site or applied to the tendon) has not shown consistent improvement in healing rates in RCTs; currently not recommended as routine

• The `critical zone` and tendon-to-bone healing: tendon-to-bone healing after rotator cuff repair progresses through inflammation (0–2 weeks), proliferation (2–6 weeks), and remodelling (6 weeks–12 months+); the healed tendon-to-bone interface does not regenerate the native fibrocartilaginous enthesis (four-zone transition — tendon-fibrocartilage-mineralised fibrocartilage-bone) — instead it heals with fibrovascular scar tissue; this inferior healing quality at the repair site is a major reason for re-tear; biological strategies to improve enthesis healing are an active research area
• Re-tear rates: highly dependent on tear size and patient factors; meta-analysis data: small tears — re-tear rates 15–20%; medium tears — 20–30%; large tears — 30–50%; massive tears — up to 70–80%; Goutallier III–IV — re-tear rates approach 70–90%; re-tear does not necessarily predict functional failure — many patients maintain acceptable function with a re-torn repair (the scar tissue provides some stability); the key outcome is functional result rather than structural integrity
• Rehabilitation after rotator cuff repair: post-operative immobilisation in a sling (4–6 weeks for small/medium tears; 6 weeks for large/massive tears); passive range of motion (Codman pendulum exercises) from early post-op (days 1–2) to prevent stiffness while protecting the repair; active-assisted ROM begins at 6 weeks; active ROM and early strengthening at 12 weeks; return to overhead activity and sport at 6 months; full return to heavy manual work at 9–12 months; premature loading of the repair (before adequate tendon-to-bone healing has occurred — approximately 8–12 weeks) is the most common cause of re-tear

• Tear classification: Ellman — small <1 cm, medium 1–3 cm, large 3–5 cm, massive ≥5 cm or two+ tendons; Goutallier fatty infiltration 0–IV; Grade III–IV = poor muscle quality → high re-tear risk → relative contraindication to repair
• Critical zone: 5–10 mm from supraspinatus insertion; most avascular region; most common tear site; tendon-to-bone healing here produces fibrovascular scar NOT native enthesis fibrocartilage
• Subscapularis-specific tests: bear-hug test (most sensitive); belly-press test; lift-off test; subscapularis tears commonly missed — specifically examine if long head biceps pathology or medial bicipital groove pain present
• Double-row repair: medial row (articular margin) + lateral row (greater tuberosity); restores native footprint; biomechanically superior; clinical advantage for large tears (>3 cm) — significantly lower re-tear rates in meta-analyses; no advantage over single-row for small/medium tears
• Suture-bridge (transosseous-equivalent): medial anchors + lateral knotless anchors bridging the tendon against the footprint; maximum footprint restoration and compression; most common double-row configuration
• CSAW trial (BMJ 2018): acromioplasty = sham surgery = physiotherapy for subacromial impingement without cuff tear; decompression alone not justified for impingement; appropriate as part of repair surgery field preparation
• Re-tear rates by size: small 15–20%; medium 20–30%; large 30–50%; massive 70–80%; Goutallier III–IV 70–90%; functional outcome does not always mirror structural integrity — re-torn repairs can maintain good function
• Rehabilitation protocol: sling 4–6 weeks; passive ROM (pendulums) day 1–2; active-assisted at 6 weeks; strengthening at 12 weeks; overhead/sport at 6 months; heavy labour 9–12 months; premature loading = most common cause of re-tear
• Hamada classification: cuff tear arthropathy; Grade I (AHI ≥6 mm) → Grade V (glenohumeral OA); Grade III+ or pseudoparalysis in elderly → consider RSA rather than repair
• Irreparable massive tear options: partial repair (latissimus dorsi transfer, lower trapezius transfer for posterosuperior); superior capsular reconstruction (fascia lata allograft — bridges supraspinatus footprint to glenoid to prevent superior humeral migration); reverse shoulder arthroplasty (for elderly with cuff tear arthropathy and pseudoparalysis)