Triceps Tendon Rupture

History: sudden sharp pain at the posterior elbow during a fall on outstretched hand or eccentric loading event; a palpable or audible pop is sometimes described; immediate swelling and bruising over the posterior elbow; weakness or inability to extend the elbow, particularly against resistance. Review risk factors explicitly (anabolic steroid use, steroid injections, CKD, diabetes, underlying tendinopathy) and consider the demographic split: younger/weightlifting with anabolic use versus older with systemic disease.

Examination:

• •Focal tenderness over the distal triceps and olecranon
• •Posterior elbow swelling, ecchymosis, and a palpable gap immediately proximal to the olecranon in complete rupture (may be masked by haematoma in the first 24-48 hours)
• •Active elbow extension AGAINST GRAVITY may still be possible in complete ruptures because the lateral triceps expansion, anconeus, and residual deep fibres can maintain some extension. ALWAYS test against RESISTANCE - resisted extension weakness is often the key bedside clue
• •Overhead extension test: asking the patient to raise the arm vertically overhead and extend the elbow against gravity in that position eliminates gravity assistance and can unmask a complete rupture that looks deceptively intact with the arm at the side
• •Modified triceps squeeze test (adjunct): patient prone with the elbow flexed over the couch edge, squeeze the triceps muscle belly and watch for passive elbow extension. Useful when the palpable gap is obscured, but less established than the core findings
• •Assess ulnar nerve function (sensory ulnar 1.5 fingers, intrinsic motor, Froment's sign): ulnar dysfunction can coexist with distal triceps injury
• •Passive range of motion is typically preserved; active extension is reduced or absent

Red flags: open wound over the posterior elbow (open tendon injury or fracture); absent or diminished ulnar nerve function suggesting concomitant nerve injury; features of compartment syndrome (rare, reported after crush injury).

Differentials: olecranon fracture (loss of active extension plus focal bony tenderness, distinguished on radiographs); olecranon bursitis (septic or aseptic, focal posterior swelling but intact resisted extension); distal biceps tendon rupture (anterior elbow, reverse Popeye, negative hook test, supination weakness); ulnar collateral ligament injury (medial pain, valgus instability, not an extension deficit); acute olecranon enthesitis or tendinopathy without rupture (tenderness but preserved resisted extension); posterior elbow dislocation (gross deformity).

Plain radiographs (AP and lateral elbow):

• •First-line in suspected rupture
• •The flake sign (a small avulsion fragment from the olecranon tip on the lateral view) is the classic radiographic clue, reported in approximately 60-90% of complete ruptures, but is NOT universal
• •Exclude coexisting olecranon fracture or posterior elbow dislocation
• •Usually normal in pure intra-tendinous tears

Ultrasound: rapid, accessible first-line soft-tissue investigation in experienced hands. Dynamic assessment during active extension can demonstrate a tendon gap and grade the injury. Particularly useful for distinguishing partial from complete rupture and for identifying the layer involved (superficial aponeurotic versus deep medial head).

MRI: the preferred cross-sectional imaging investigation where partial rupture, chronic tear, surgical planning, or equivocal examination requires clarification. Grades the tear, quantifies retraction, and assesses tendon quality and muscle bulk. Typically arranged via secondary care rather than routinely in primary care.

Additional assessments:

• •Blood tests (urea and electrolytes, calcium, parathyroid hormone) may be considered where renal failure, secondary hyperparathyroidism, or metabolic tendinopathy is suspected clinically
• •Consider a direct but non-judgemental discussion about anabolic steroid use in the demographic where this is plausible

Open injuries follow BOAST-aligned open-injury principles.

Non-operative management:

• •Appropriate for partial tears with preserved functional extension, older or low-demand patients, and those unfit for or declining surgery
• •Short-term sling for comfort only; early pain-free range of movement within a protected arc (avoid deep flexion early, which stresses the repair zone)
• •Structured physiotherapy focused on restoring extension endurance and elbow range of movement
• •Close follow-up at 4-6 weeks; clinical deterioration or progression to complete rupture mandates surgical review

Operative management (standard for complete rupture in active patients):

• •Primary surgical repair is the default in active patients. Selected low-demand or medically unfit patients may still be managed non-operatively, accepting some extension weakness
• •Primary repair is generally easiest and most reliable in the first few weeks after injury; aim for specialist assessment within 1-2 weeks
• •Delayed presentations remain manageable but become technically more demanding and may require graft reconstruction or tendon-transfer salvage options in rare cases
• •Standard techniques include transosseous tunnels, suture anchors, and cortical button fixation; functional outcomes are broadly comparable

Red flag / urgent features: open injury or exposed tendon (urgent theatre, IV antibiotics within 1 hour, tetanus, BOAST open-injury principles); associated ulnar nerve deficit or progressive neurological change (urgent specialist referral); compartment syndrome (urgent fasciotomy).

Complications: re-rupture (more common with delayed repair and early return to heavy loading); ulnar nerve neuropraxia or injury (particularly at risk during medial-sided dissection); olecranon bursitis or persistent posterior discomfort; elbow stiffness (particularly loss of terminal flexion after prolonged immobilisation); heterotopic ossification (uncommon, may follow high-energy injury or prolonged immobilisation).

Referral: urgent shoulder/elbow specialist for suspected complete rupture in an active patient, aiming for specialist assessment within 1-2 weeks; routine for partial tears with persistent symptoms despite 4-6 weeks of structured rehabilitation; primary care management for confirmed partial tears with good functional extension in older or low-demand patients.

Typical pathway only. Progression varies by injury pattern, repair construct, and surgeon preference. Local protocols and surgeon or physiotherapist advice take precedence.

Non-operative (partial tears with preserved function):

• •Short-term sling for comfort (1-2 weeks)
• •Early protected active and active-assisted range of movement within a surgeon- or physiotherapist-guided safe arc
• •Avoid forced passive stretching of the elbow (especially deep passive flexion) in the early phase
• •Progressive resisted extension from 6 weeks onwards
• •Return to non-resisted daily activity typically within 6-8 weeks; return to heavier resistance activity individualised

Post-operative (primary repair):

• •Brace or posterior slab in approximately 30-40 degrees of flexion in the early phase (typically 2 weeks) to protect the repair
• •Protected active-assisted flexion within a guarded arc from 2 weeks under physiotherapy supervision; avoid forced passive flexion
• •Active extension is usually protected against resistance for 6-8 weeks
• •Progressive strengthening from 8-12 weeks
• •Return to light manual duties typically from 3 months; heavy manual work, resistance training, or contact sport typically from 4-6 months, guided by the operating surgeon

Key principles: early controlled MOVEMENT is protective - prolonged rigid immobilisation produces stiffness; forced passive stretching is CONTRAINDICATED (stresses the repair and provokes heterotopic ossification); structured physiotherapy is essential. Modifiable factors: smoking cessation, optimisation of diabetes and renal disease, explicit counselling around anabolic steroid use and further local steroid injection.

• •BESS shoulder and elbow guidance hub - UK framework for triceps tendon rupture; primary surgical repair is the default for complete rupture in active patients with specialist assessment within 1-2 weeks.
• •Anzel & Anson (1959) - The classic series defining triceps rupture as fewer than 1% of upper-limb tendon injuries and establishing the eccentric-loading mechanism. Underpins the modern demographic split (younger anabolic steroid users vs older systemic-disease patients).
• •Flake sign on lateral radiograph - Reported in approximately 60-90% of complete triceps ruptures across imaging series. Highly suggestive but NOT universal; absence does not exclude rupture.
• •BOAST Management of Open Fractures - Governs open triceps injury: IV antibiotics within 1 hour, tetanus management, limited wound handling, photographic documentation, urgent senior orthopaedic input.
• •Secondary hyperparathyroidism in CKD - Recognised cause of spontaneous tendon rupture in dialysis patients; rationale for considering urea, electrolytes, calcium, and parathyroid hormone when the demographic and history suggest metabolic tendinopathy.

• •Triceps tendon rupture is rare (less than 1% of upper-limb tendon injuries). Demographic split: YOUNGER ruptures linked to anabolic steroids and weightlifting; OLDER ruptures linked to systemic disease (CKD with secondary hyperparathyroidism, diabetes, corticosteroid exposure).
• •Classic mechanism: eccentric load on a contracting triceps during a fall on outstretched hand. Two-layer tendon anatomy means partial ruptures typically involve the superficial aponeurotic layer and spare the deep medial head.
• •Preserved extension against gravity does NOT exclude a complete tear - the anconeus and lateral triceps expansion can maintain weak extension. ALWAYS test against RESISTANCE. The overhead extension test eliminates gravity assistance and can unmask a complete tear.
• •Flake sign on lateral radiograph is the classic clue, present in 60-90% of complete ruptures but not universal. Ultrasound is useful for dynamic assessment and grading the layer involved; MRI is preferred for partial tear characterisation, chronic injuries, and surgical planning.
• •Complete ruptures in active patients should be referred urgently for primary surgical repair - aim for specialist assessment within 1-2 weeks. Non-operative management is reserved for partial tears with preserved function, or older / low-demand patients.
• •Ulnar nerve is vulnerable during operative repair - assess and document pre-operatively. Forced passive stretching of the elbow is CONTRAINDICATED during rehabilitation; it stresses the repair and increases heterotopic ossification risk.