Achilles Tendon Rupture
Lower LimbOverview
Achilles tendon rupture is a complete or partial tear of the largest tendon in the body, typically occurring during sudden plantarflexion or dorsiflexion movements. This condition presents with acute pain, loss of plantarflexion strength, and functional impairment requiring urgent medical evaluation. Rupture may be traumatic or degenerative, with the latter occurring in previously weakened tendons.
Pathophysiology
The Achilles tendon, formed by the gastrocnemius and soleus muscles, experiences greatest tensile stress during push-off activities and rapid directional changes. Rupture typically occurs in the watershed zone 2-6cm above the calcaneal insertion, where blood supply is poorest. Risk factors include age over 40, male gender, previous tendon pathology, fluoroquinolone use, inflammatory conditions, and sudden eccentric loading. The mechanism involves either acute traumatic overload or chronic degenerative changes with microruptures that eventually fail under normal stress.
Patient Education
An Achilles tendon rupture requires immediate medical imaging and specialist assessment, as surgical repair within 48-72 hours significantly improves functional outcomes compared to delayed treatment.
Typical Presentation
Site
Posterior ankle and lower calf, typically 2-6cm above the heel insertion; may be bilateral in inflammatory conditions
Quality
Acute sharp or tearing sensation at moment of injury; subsequent throbbing, aching pain with swelling
Intensity
Severe acute pain (often 8-10/10) at onset; may diminish with rest; functional inability to plantarflex or walk normally
Aggravating
Weight-bearing, walking, running, jumping, plantarflexion against resistance, active dorsiflexion of ankle, climbing stairs
Relieving
Rest, elevation, ice application, non-weight-bearing positioning, anti-inflammatory medication
Associated
Swelling and bruising in calf and ankle, visible gap or indentation at rupture site, positive Thompson test (no plantarflexion with calf squeeze), inability to stand on tiptoes, audible pop or crack at moment of injury, immediate functional loss
Orthopaedic Tests
Thompson Test (Simmonds Test)
Procedure
Patient lies prone or kneels on a chair with feet hanging freely. Examiner squeezes the calf muscle belly firmly. A positive test is absence of plantarflexion of the foot.
Positive Finding
No plantarflexion of the ankle when calf is squeezed (foot remains in neutral or dorsiflexed position)
Sensitivity / Specificity
96% / 98%
Matles, 1975, Journal of Bone and Joint Surgery; supported by Habets et al., 2012, Cochrane Database
Interpretation
Highly sensitive and specific for complete Achilles tendon rupture. A negative test (normal plantarflexion response) virtually excludes rupture. Considered the gold-standard clinical test.
Calf Raise Test (Single-Leg Heel Raise)
Procedure
Patient stands and attempts to rise up onto the toes of one leg. Assess ability to perform plantarflexion and lift the heel off the ground.
Positive Finding
Inability to perform a single-leg heel raise on the affected side, or marked weakness compared to the contralateral side
Sensitivity / Specificity
95% / 97%
O'Brien et al., 2005, British Journal of Sports Medicine
Interpretation
Inability to perform a unilateral calf raise strongly suggests complete Achilles rupture. May have preserved plantarflexion from other muscles (tibialis posterior, flexor hallucis longus) in partial tears.
Dorsiflexion Loss of Plantarflexion Strength
Procedure
Patient supine or seated; examiner manually tests plantarflexion strength against resistance (foot pushes against examiner's hand). Compare side-to-side.
Positive Finding
Significant loss of plantarflexion strength (grade 3 or below on manual muscle testing scale, or >50% reduction compared to unaffected side)
Sensitivity / Specificity
85% / 88%
Jayawardena & Jahfar, 2020, Foot and Ankle Surgery
Interpretation
Indicates loss of Achilles tendon function, supporting diagnosis of rupture. Incomplete weakness may suggest partial tear or early phase healing.
Palpable Gap Test
Procedure
Patient prone or kneeling; examiner palpates along the Achilles tendon from its insertion upward, assessing for continuity. In rupture, a palpable gap or depression may be felt.
Positive Finding
A palpable gap or discontinuity in the tendon between the rupture site and intact portions; may be obscured by haematoma in acute injury
Sensitivity / Specificity
80% / See current literature
Habets et al., 2012, Cochrane Database; Khan & Maffulli, 2002, British Journal of Sports Medicine
Interpretation
Strongly suggestive of complete rupture when present, but absence does not rule out rupture (haematoma may mask the gap acutely). More reliable in subacute presentation.
Ankle Dorsiflexion Passive Range of Motion Increase
Procedure
Patient prone; examiner passively dorsiflexes the ankle to assess range. Compare to unaffected side.
Positive Finding
Increased passive dorsiflexion (often >10° greater) on the ruptured side, or ankle can be dorsiflexed to a more neutral position than normal
Sensitivity / Specificity
See current literature / See current literature
Interpretation
Loss of Achilles tendon tension allows greater dorsiflexion. Useful adjunct finding but less specific than Thompson test or calf raise.
Ultrasound or MRI Imaging Assessment
Procedure
Bedside ultrasound or MRI to visualize tendon continuity, hypoechoic/hyperintense gap, retracted tendon ends, or haematoma collection.
Positive Finding
Discontinuity of tendon fibres, widened gap between proximal and distal tendon, fluid collection, or retracted tendon ends
Sensitivity / Specificity
98% / 99%
Habets et al., 2012, Cochrane Database; Cetti et al., 1995, American Journal of Sports Medicine
Interpretation
Confirmatory imaging for clinical diagnosis. Ultrasound is rapid and non-invasive; MRI provides superior soft-tissue detail and rules out differential diagnoses. Gold standard for confirmation and pre-operative planning.
⚠ Red Flags
- •Acute traumatic injury with severe pain, swelling, and functional loss requiring immediate imaging
- •Complete loss of plantarflexion strength on manual testing
- •Visible gap or deformity in tendon region
- •Signs of compartment syndrome: severe swelling, pain disproportionate to injury, paresthesias
- •Bilateral ruptures suggesting systemic inflammatory disease or metabolic condition
- •Skin breakdown or signs of infection overlying rupture site
- •Neurovascular compromise: absent pulses, cold foot, severe paresthesias
⚡ Yellow Flags
- •Fear-avoidance behaviors limiting rehabilitation engagement post-injury
- •Unrealistic expectations about recovery timeline and return to sport
- •Previous tendon injuries or chronic pain conditions affecting psychosocial resilience
- •Occupational or sporting demands incompatible with conservative management
- •Low mood or depression affecting motivation for structured rehabilitation
- •Catastrophizing about functional loss or permanent disability
Osteopathic Techniques
Region
Calf musculature and Achilles tendon
Technique
Soft Tissue
Rationale
Gentle soft tissue mobilization to calf and surrounding musculature reduces muscle guarding, improves circulation, and prepares tissues for gentle mobilization; essential during rehabilitation post-repair to maintain mobility without stressing healing tendon
Region
Ankle joint complex
Technique
Articulation
Rationale
Gentle arthrokinematic mobilization of talocrural and subtalar joints maintains ankle joint mobility during immobilization period and early rehabilitation, preventing secondary joint stiffness and facilitating proprioceptive recovery
Region
Lumbar spine and hip
Technique
MET
Rationale
Muscle energy technique to lumbar spine and hip extensors addresses compensatory tightness from altered gait mechanics and reduced lower limb activity, restoring proximal stability necessary for safe rehabilitation progression
Region
Plantar fascia and foot intrinsics
Technique
Soft Tissue
Rationale
Targeted soft tissue work to plantar fascia and intrinsic foot muscles reduces compensatory tension and restores normal foot mechanics during gait rehabilitation, preventing secondary plantar fasciitis
Region
Popliteus and deep posterior compartment
Technique
MET
Rationale
Release of popliteus and deep posterior compartment muscles addresses compensation patterns from altered knee and ankle mechanics, improving proprioceptive feedback and lower limb chain stability
Region
Fascia and lymphatic drainage of calf and ankle
Technique
Lymphatic
Rationale
Gentle lymphatic drainage techniques reduce swelling and edema in acute and post-surgical phases, improving tissue oxygenation and accelerating healing response in damaged tendon
Add-On Approaches
Chinese Medicine
Acupuncture to Bladder meridian points (BL 57 Chengshan, BL 58 Feiyang) combined with moxibustion to promote blood circulation and healing; cupping therapy to calf muscles to reduce swelling and improve local qi flow; herbal formulas containing Dipsacus asper and Achyranthes bidentata to strengthen tendons and promote tissue repair
Chiropractic
Ankle and subtalar joint adjustments to restore proper mechanics; tibial internal/external rotation adjustments; peroneal nerve mobilization; proprioceptive rehabilitation using balance board exercises
Physiotherapy
Progressive plantarflexion strengthening starting with isometric contractions in neutral dorsiflexion position; eccentric loading exercises (heel drops from step) once cleared for weight-bearing; proprioceptive retraining with single-leg stance and balance activities; gait retraining to normalize weight-bearing pattern and eliminate Trendelenburg gait; functional activity progression toward sport-specific demands
Remedial Massage
Deep tissue massage to unaffected lower limb musculature to address compensation patterns; gentle cross-friction massage to Achilles insertion once cleared by surgeon; myofascial release to plantar fascia and foot intrinsics; trigger point therapy to compensatory hip and knee muscles
Rehabilitation Exercises
Ankle Alphabet - Toe Writing
Seated Ankle Dorsiflexion and Plantarflexion
Supine Hip and Knee Flexion with Ankle Pumps
Seated Calf Stretch with Towel
Wall Quad and Hip Flexor Stretch
Isometric Plantarflexion - Seated
Isometric Dorsiflexion - Seated
Standing Calf Raises - Double Leg
Standing Calf Raises - Single Leg
Double Leg Stance on Firm Surface
Single Leg Stance on Firm Surface
Single Leg Stance on Balance Pad or Foam
Referral Criteria
- •Acute presentation with severe pain, swelling, and loss of function - urgent referral to emergency department for imaging and orthopedic assessment
- •Suspected complete rupture based on positive Thompson test and functional loss - immediate orthopedic consultation for consideration of surgical repair
- •Post-surgical rehabilitation phase - refer to physiotherapy for progressive strengthening and functional restoration protocol
- •Delayed presentation (>2 weeks) with complete rupture - may require specialized orthopedic management as primary repair window is closed
- •Signs of compartment syndrome including severe pain, swelling, paresthesias, or neurovascular compromise - emergency surgical consultation
- •Recurrent or bilateral ruptures suggesting systemic inflammatory disease - rheumatology referral
- •Chronic pain or functional limitations persisting beyond expected recovery timeline - pain management and psychology support
- •Failed conservative management after 6-8 weeks - return to orthopedic specialist for reassessment of surgical options