Tendon repair is most commonly required after a cutting injury (with a knife, angle grinder, broken glass, circular saw etc). Sometimes a tendon can rupture without an external wound - such as in a mallet finger injury.
The tendons on the back of the hand and forearm are termed "extensor tendons" - they work to extend the hand and forearm. The tendons on the front of the hand and forearm are termed "flexor tendons" - they flex the hand and forearm. The two different types of tendons have different rehabilitations and recovery periods.
Surgical repair of an injured tendon is necessary to ensure that the tendon can regain its full function. In complex injuries it may not be possible to determine before the surgery exactly which hand and wrist structures are injured, and to what degree they are injured. Sometimes people with simple wounds undergo exploratory surgery reveals that no major structures were injured.
The strength of a flexor tendon repair varies according to the type of sutures that are placed during surgery. Tendon repairs that have more strands in the repair generally give greater strength, with less risk of tendon rupture during the recovery period. The surgeon also has to use careful technique so the repair part is not made so large by the stitches that it can't slide back and forth properly, especially for tendon injuries in the fingers.
Tendon repair surgery is usually performed as day case surgery. In some instances it may be possible to undertake the surgery as wide awake hand surgery - discuss this with your surgeon.
What can go wrong (complications)?
The complications of tendon repair that I worry most about are tendon rupture (where the repair ruptures) and tendon scarring (where scar formation leads to stiffness of the fingers, hand or wrist). You can minimise the risk of rupture and tendon scarring by following your surgeon and therapist's rehabilitation instructions exactly. Hand therapy is a very important part of your recovery. If you do not follow your therapist's instructions then it is very unlikely that you will regain full movement of your fingers or hand. If your tendon ruptures after its repair you will almost certainly need further surgery, and the final outcome will often be compromised.
Other possible complications include allergic reaction, altered skin sensation, painful scarring, damage to associated structures (nerves, arteries), infection, inability to restore function, pain (including complex regional pain syndrome), skin contour irregularity, tendon scarring and unsatisfactory results.
Complications such as the remote risk of death or serious disability exist with any surgical procedure but are extremely unlikely with tendon repair surgery.
What sort of hand therapy is involved?
Extensor tendons are immobilised completely until they regain their strength. If the repaired tendon is 100% divided it is likely you will need to wear a splint for 4 weeks to immobilise the affected tendon(s). If the injury to the tendon is less than 100% the immobilisation period may be shorter.
If your surgeon is confident with the strength of a flexor tendon repair you will be instructed to commence a rehabilitation program within 48 hours of the surgery (termed "early active mobilisation"). You may be shown the sort of exercises demonstrated in the video below. IMPORTANT: do not move your hand or fingers after surgery unless you have specifically been told to do so by your surgeon or hand therapist. You are at high risk of rupturing your tendon if you undertake activities that place a greater load on the tendon than is permitted.
A flexor tendon injury usually requires 6 weeks of full time splinting, then further weeks of rehabilitation are required to regain movement, reduce swelling and address scarring and stiffness.
For more information about different types of flexor tendon injuries, surgical repairs and rehabilitation protocols you may wish to read this page by Dr Ramona Bates, a US plastic surgeon.
When will I return to full function?
Every injury, patient and recovery varies so please ask your surgeon and therapist this question.