Loss of active extension
The finger, thumb or wrist cannot be fully straightened.
Back-of-hand tendon injury · Hand trauma
Extensor Tendon Injury & Repair Symptoms & Treatment
A cut or impact to the back of the hand can damage the tendons that straighten the fingers. Drooping, loss of extension or an open wound should be assessed promptly so that splinting, repair and therapy can be planned before stiffness or deformity develops.
Cannot straighten fingerBack-of-hand cutFinger droopOpen injury
Patient guideSymptoms → Diagnosis → Treatment → Recovery
Specialist hand & wrist assessment
What is injured?
The thin extensor tendons that straighten the finger, thumb or wrist.
Common clue
A finger or joint cannot be actively straightened even though it may be moved passively.
Treatment
Splinting for selected closed injuries or repair for open/complete lacerations.
Recovery
Protected movement and hand therapy continue for weeks while the repair regains strength.
Understanding the condition
What is an extensor tendon injury?
Extensor tendons lie close beneath the skin on the back of the hand and fingers. They straighten the joints and coordinate complex finger movement through the extensor mechanism.
Because they are superficial, they can be injured by relatively small cuts. Closed impacts can also tear or detach tendon structures, leading to mallet finger or boutonnière deformity.
Clear diagnosis before treatmentSimilar symptoms can arise from the neck, elbow, wrist, tendons or joints. The examination is designed to locate the true source.
What patients may notice
Symptoms worth checking early.
Symptoms vary with the tendon or finger structure involved and how long function has been affected. Persistent locking, weakness, deformity or loss of movement deserves specialist assessment.
Finger droop
The fingertip or middle joint may rest in a bent position.
Back-of-hand wound
Even a small cut can divide the superficial tendon.
Pain and swelling
Tenderness may follow a direct blow or laceration.
Extension lag
The joint can be moved straight passively but cannot hold the position actively.
Developing deformity
Untreated central slip injury may progress to boutonnière deformity.
Why it happens
How extensor tendons are injured
A useful consultation connects the symptom pattern to the exact tendon, pulley or joint involved—not just the label.
Sharp laceration
Glass, metal or a knife can divide the tendon on the back of the hand.
Direct blow
A ball or impact can force a finger joint to bend and rupture the tendon.
Fracture or dislocation
Bone injury may detach the tendon or disrupt the extensor mechanism.
Attrition or inflammatory disease
Arthritis or chronic tendon wear can cause delayed rupture.
Focused diagnosis
Find the structure, the injury and the severity.
The examination identifies which extensor zone is involved, tests each joint separately and checks for fracture, joint instability, nerve injury and wound contamination.
Bring to your appointmentPrevious reports, imaging, operation notes, splints and information about work or activities that trigger symptoms.
Mechanism and wound assessment
The position of the cut or impact predicts which tendon structure may be injured.
Active extension testing
Each joint is assessed for extension strength and lag.
Special tests
Targeted manoeuvres can help assess the central slip and lateral bands.
X-ray and selected ultrasound
Imaging may identify fracture, joint alignment, foreign body or tendon discontinuity.
Treatment choices
Start with the option that fits the diagnosis.
Surgery is not automatic. Treatment is matched to the exact tendon or finger problem, symptom severity, function and the patient’s goals.
Non-surgical care
Reduce irritation, protect function and review progress.
- Continuous splintingSelected closed injuries are treated by holding the affected joint in a precise position.
- Skin and wound careOpen injuries require proper cleaning and assessment even when movement appears partly preserved.
- Hand therapyCustom splints and carefully timed exercises protect healing while reducing stiffness.
- Activity restrictionForceful gripping, lifting and unsupported joint flexion are avoided during healing.
- Monitor extension lagLoss of position or increasing droop should be reviewed promptly.
Surgical pathway
Restore extension and protect the repair through staged therapy.
- Primary extensor tendon repairA complete open laceration may be sutured directly.
- Bone or joint fixationAssociated fracture or dislocation may require stabilisation.
- Tendon reconstructionDelayed or complex injuries may need grafting, transfer or staged treatment.
- Protected rehabilitationPostoperative splinting and therapy depend on the tendon zone and repair strength.
Surgery when appropriate
Extensor tendon repair surgery
Surgery is commonly required for complete open lacerations and selected displaced fractures, unstable injuries or failed splint treatment.
- Define the injured extensor zone and associated damage
- Clean and prepare the wound
- Repair tendon and stabilise bone or joint if required
- Apply the correct protective splint
- Begin zone-specific hand therapy
Realistic expectationsExtensor repairs are thin and vulnerable. Strict splinting and therapy reduce the risks of rupture, stiffness, adhesions and persistent extension lag.
Specialist pathwayDiagnosis → Procedure → Therapy → Recovery
Recovery pathway
Healing is staged—not rushed.
Timelines are guides only. The diagnosis, procedure, wound, therapy programme, job and associated injuries all influence recovery.
First days
The repair is protected in a splint and the wound is monitored.
First 4–6 weeks
Exercises are carefully controlled by the hand therapist and depend on the repair zone.
6–12 weeks
Movement and light function progress while the tendon continues to regain strength.
Around 3 months and beyond
Heavier use is introduced only after adequate healing and clinical review.
4.96/555 verified reviewsWhy consult Dr Arshad
A clear diagnosis. Practical options. A plan built around you.
Dr Shoaib Arshad is a fellowship-trained consultant orthopaedic hand and wrist surgeon with UK specialist training and more than 17 years in orthopaedic surgery.
Focused hand, wrist and upper-limb assessmentNon-surgical and surgical treatment pathwaysPrivate consultations at The Highfield Hospital, Rochdale, for patients across Greater Manchester and the North West
Meet Dr Arshad ↗Questions patients ask
Extensor Tendon Injury FAQs.
General information only. Your diagnosis and treatment plan should be based on an individual medical assessment.
Can an extensor tendon heal without surgery?+
Some closed injuries can heal with precise continuous splinting. Complete open lacerations often need surgical repair.
Why must the splint position be exact?+
The tendon heals at a specific length. Allowing the joint to bend can separate the healing ends and lead to a persistent droop.
How long does an extensor repair take to strengthen?+
The tendon commonly remains vulnerable for about three months, though the exact rehabilitation plan depends on the injury zone.
What is an extension lag?+
The joint can be straightened passively but cannot hold full extension actively because the tendon mechanism is weak or elongated.
Where does Dr Arshad see patients?+
Dr Arshad sees private patients at The Highfield Hospital, Manchester Road, Rochdale OL11 4LZ — within easy reach of Manchester, Oldham, Bury, Bolton and the wider North West. You can book online through Circle Health Group, call +44 7443 213645, or send an enquiry and the team will help.
Medical referencesPatient information sources used for this guide
The Highfield Hospital · Rochdale, Greater Manchester
Ready for a clear tendon and finger assessment?
Request a specialist consultation and bring any previous imaging, reports, splints or treatment information.