Tendon injuries of the hand and plastic surgery

We often focus on tendons when there is some damage to them. In today’s article we take a closer look at tendons and for that purpose we produce excerpts of an interview done with Dr. Shashanka Rathnayake, Consultant Plastic and Reconstruction Surgeon at the Teaching Hospital, Kandy.

Q  What is a tendon injury ?
 A tendon is a very strong tissue made of collagen fibres. Most of the muscles form a tendon which gets attached to a bone. They are responsible for the movements of the limbs. The tendon architecture of the hand is not simple. Each finger is controlled by about six tendons. The thumb is controlled by eight tendons.

The tendons of the hand could get injured by various reasons but cut injury is the commonest. When a cut injury occurs in the hand and one or more fingers are not working people tend to think that it is due to a nerve damage. Usually it is due to a tendon damage and can be corrected immediately with surgical repair. If the loss of function is due to nerve damage it will not become functional immediately after repair. It is an important thing to understand. However, when nerve is repaired hand functions will become normal.

Q What is the role of the plastic surgeon in tendon injury management?
 The architecture of the tendons in the hand is complex. Each flexor tendon in the hand goes through a Pulley system which consists of fibrous sheaths making the tendon gliding smooth and mechanically sound function. If the pulley system is damaged the tendons will not function properly.

 Therefore, the tendon repairs in the hand has to be done meticulously and with  a good understanding of the complex anatomy of the hand. The tendon injuries in the lower part of the finger was considered as the worse tendon injuries during the second world war. The surgeons recommended amputation of a finger for a tendon injury as it cannot be repaired properly and non functional finger after repair is going to impair the function of the other fingers.

Plastic surgeons involved in the tendon repairs of the hand and could produce good results. One should understand that it is not a simple suturing and requires lot of experience

 This can be explained easily by asking the patient to hold the middle finger and try to grip something. The strength of the hand grip would be impaired.

 Plastic surgeons involved in the tendon repairs of the hand and could produce good results. One should understand that it is not a simple suturing and requires lot of experience in handling the soft tissues delicately. The tendon repair should not be bulky and should move through the pulley system smoothly.

 The fingers undergone flexor tendon repairs would be mobilized from day one after surgery. This is done with a extensor blocking splint under supervision of an occupational therapist. This early mobilization prevents tendon adhesions to each other and pulley system and improves function. Unfortunately, the flexor tendon repairs are immobilised after repair and it leads to undesirable poor outcome.

Q  What will happen if a tendon is not repaired properly? 
Obviously the hand will lose some of the function and may be serious issue especially when occurs with dominant side. The secondary reconstruction of the tendon injury is not going to be simple and rehabilitation would be difficult and prolonged. Usually a flexor tendon reconstruction is done in two stages. First the pulley system through which the tendon is gliding is reconstructed using a silicon rod and it is kept for 3 months to allow a tendon sheath to develop. In the second stage the tendon is replaced with a tendon graft and mobilisation is stared following day after surgery. However, the hand cannot be used for manual work for another three months. It is a long process of six months altogether to regain the function of a tendon which was missed to repair or improperly repaired and cannot be considered as simple matter.

 In addition the patient who is usually the sole bred-win of the family will have to be away from work unnecessarily for a longer period causing economic problems to the family. This is why neglecting a tendon injury has become a social problem in our country. Unfortunately, our citizens are fond of going behind untrained and unscientific indigenous practitioners to get these complex problems sorted.

Q How do you repair tendons in a better way ?
 The hand should be operated in bloodless field using a special instrument called tourniquet over the upper arm or forearm so that the surgeon could see the structures well. In addition, the suture material should be very strong to hold the tendon ends under tension. The technique of the repair is also equally important and should not be taken easy. If the tendon is repaired properly it will function properly.

In addition, the tendons can be badly damaged with loss of a segment. In this case just suturing of the tendon cannot be done. The tendon has to be reconstructed using a tendon graft taken from the forearm or lower leg. There are some tendons in the body which are not serving a useful function and can be successfully used in this kind of a situation.

Q What are the other factors important in a successful tendon repair?
 We believe in a proper, strong repair and early active mobilization. The rehabilitation of the hand injuries is very important and should be done by a qualified therapist under the plastic surgeon’s supervision. There is no point repairing tendons in the hand if there is no understanding about the rehabilitation.

 It is also important to protect the tendon repair till it heals to the previous strength. Some patients think that when the finger starts working after surgery, it is suitable for using to do the normal work. After a tendon repair the injured area takes about three months to gain its normal strength. So it should not be used for work for such a long time but the fingers should be started to mobilise from the following day of surgery. This is a point some cannot understand and leads to poor results.

 The mobilisation of the finger or fingers as well as protection of them breaking due to some accidental force cannot be done by a conventional way of splinting. As used in the developed world we need to use a removable splint made of Thermoplastic material.

Q What would you do if the repaired tendon is not functioning properly?
 This is an unfortunate situation and should be handled with a good understanding between doctor and patient. If the patient is not cooperative, the results would be poor even though surgeon is skillful. We usually try therapy for about three months and if there is lack of progress in gaining the function, the repair has to be explored. Usually, this situation is due to adhesions around the tendons. We  clean these adhesions and start mobilisation immediately after surgery to prevent adhesion formation again and the patient has to closely follow up the therapist advice under supervision of the Plastic surgeon.

Q What is the duration of a tendon operation?
The repair of a tendon is not very urgent. It could be repaired successfully within few days. However, when it is delayed in weeks the repair would be difficult as the pulley system get scarred and narrow without the tendon gliding.

 In such a case the pulley system has to reconstructed in addition to the tendon repair and it is a complex operation should be ideally done by a plastic surgeon. Sometimes this kind of operation has to be done in two stages, three months apart. The first operation is to reconstruct the pulleys and placing a silicone rod to create a space for the tendon to glide. The second operation is to reconstruct the tendon usually with a tendon grafts as we have already discussed.

Q What are the other options if the tendon repair is not successful? 
If a tendon repair fails it should not be given up. Repeated exploration would be much appreciated. However, there are some cases where we decide to fuse the joints instead of tendon repair. The basic working principal about the poorly functioning hand after an injury is to attempt at least to improve one grip of the hand out of the eight grips of the hand. This could be achieved with sound understanding of the nature of the injury and reconstruction followed by supervised hand therapy. In all these difficult cases patient compliance is an important contribution sometimes more than the knowledge and skill of the plastic surgeon.