the 95 ankles from 57 patients with achilles tendon tightness were included in the study .
the first group ( idiopathic ) consists of the patients with no other specific disorders ( n = 26 ) or with disorders not involving the muscle and the tendon , such as flat foot ( n = 13 ) and tibial or femoral torsion ( n = 4 ) . the next group ( neuromuscular or other disorders ) consists of the patients with disorders involving the muscle and the tendon , such as the cerebral palsy ( n = 22 ) , muscular dystrophy ( n = 12 ) , recurred or residual clubfoot deformity ( n = 10 ) , and trauma ( n = 8) .
the 84 ankles with mild ( less than 10 ) to moderate ( 10-20 ) equinus deformities were treated with the casts after the tendon lengthening , while 11 ankles with severe ( equinus more than 20 ) deformities received combination treatment of serial casts ( n = 6 ) and ilizarov gradual correction ( n = 5 ) . the mean age of the patients at the time of the surgery was 12.5 years ( range , 4 to 28 years ) .
the mean follow - up period after the surgery was 2.2 years ( range , 1.1 to 5.4 years ) .
we compared our modified technique ( 95 ankles ) to the percutaneous sliding lengthening ( 18 ankles ) and the z - lengthening with a medial longitudinal incision ( 19 ankles ) , in terms of the outcomes , the complications , the advantages , and the disadvantages , through the reviews of the patients ' medical records and the telephone interviews .
the mean age of the patients at the time of surgery was 9.8 years ( range , 4 to 12 years ) for the percutaneous sliding technique and 18.2 years ( range , 6 to 34 years ) for the z - lengthening with a longitudinal incision technique .
the first step is to identify two to three deep creases of the skin about 2 cm apart over the achilles tendon . when there is a mild to moderate equinus deformity , one skin crease of 2 to 3 cm above the tendon insertion is chosen ( fig .
1 ) . when the contracture is severe ( more than 20 ) , one or two more incisions on the proximal creases are needed for the adequate lengthening .
step 2 . the skin and fascia are carefully incised with the number 15 blade avoiding an inadvertent transverse incision underneath the achilles tendon .
the flares are used to separate the paratenon from the achilles tendon , distally and proximally .
the plantaris tendon is identified on the medial border of the achilles tendon . with the small retractors placed under the paratenon ,
the distal longitudinal tendon incision must be done carefully , in order to avoid laceration of the distal part of the transverse skin incision ( fig .
when the tip of the blade touches the calcaneus , the blade is slowly turned 90 medially and the medial 1/2 of the tendon is incised ( or a lateral 1/2 incision could be used when necessary , such as in the planovalgus with short achilles tendon ) .
extra cautions must be taken to prevent damage to the tibialis posterior nerve and vessel and to the flexor hallucis longus tendon , which passes near the medial malleolus .
the excessive advancement of the blade medially would increase the risk of damage to the neurovascular bundle .
a small retractor is placed under the deep fascia and paratenon , and the ankle is dorsiflexed to advance the cut more proximally and to provide tension in the tendon , so the surgeon could feel when the tendon is completely cut .
after 3 cm to 4 cm of a longitudinal cut proximally for mild to moderate equinus in children or 5 cm to 6 cm for moderate equinus in adolescents , the scissors are slowly turned laterally and the lateral 1/2 of the tendon is cut .
extra caution is needed in order to prevent damaging the sural nerve . a thumb ( fig .
4 ) was placed over the tip of the surgical scissors to prevent them from advancing beyond the lateral ( to protect the sural nerve ) or medial border of the tendon .
if unable to perform a dorsiflexion of the ankle after the proximal lateral cut , the plantaris tendon needs to be rechecked because it may not have been cut when the distal medial incision was done .
when deformity is severe , the second and the third proximal longitudinal incisions of the tendon are made to create a longer lateral strip .
the amount of lengthening required is determined with the medial and lateral strips of the tendon , held side by side with the thumb forceps while applying moderate tension after the ankle has been maximally dorsiflexed once or twice ( fig .
, the level of the distal end of the medial strip , which is displaced proximally following the maximal ankle dorsiflexion , is marked on the lateral strip with the ankle in the neutral position ( fig .
6 ) . a simple 2 layer , anterior and posterior suture technique is used .
the first is from the anterior side of the tendon , starting the suture and burying the knot inside the tendon ( fig .
the consistent suturing is important to prevent a palpable lump on the skin after the surgery , especially on the posterior aspect of the tendon .
step 6 . for the accurate suturing of the paratenon and fascia , it is important to identify them clearly .
the first stitch has to be done carefully to avoid suturing these two structures together with the achilles tendon located below them .
the suture binds the paratenon and the deep fascia together , and then a subcutaneous skin suture is applied .
a short leg cast with the ankle at 90 is applied for 6 weeks in the patients under 10 years of age . for additional protection , either a second short leg cast or an ankle foot orthosis
is applied for 4 to 6 weeks in the patients over 10 years of age .
the gentle active and passive ankle dorsiflexion and heel lifting exercises are gradually recommended after immobilization . any participation in active sports
we evaluated the dorsiflexion angle of the ankle before the surgery and at the latest follow - up .
the time under anesthesia for the lengthening procedure and any of the postoperative complications were also noted .
the surgical results were evaluated using the american orthopaedic foot & ankle society ( aofas ) ankle - hindfoot scale .
in addition , to evaluate the patients ' satisfaction regarding the surgical scar , we allotted another 10 points to the cosmesis of surgical scar ( fig .
the first step is to identify two to three deep creases of the skin about 2 cm apart over the achilles tendon . when there is a mild to moderate equinus deformity , one skin crease of 2 to 3 cm above the tendon insertion is chosen ( fig .
when the contracture is severe ( more than 20 ) , one or two more incisions on the proximal creases are needed for the adequate lengthening .
step 2 . the skin and fascia are carefully incised with the number 15 blade avoiding an inadvertent transverse incision underneath the achilles tendon .
the flares are used to separate the paratenon from the achilles tendon , distally and proximally .
the plantaris tendon is identified on the medial border of the achilles tendon . with the small retractors placed under the paratenon ,
the distal longitudinal tendon incision must be done carefully , in order to avoid laceration of the distal part of the transverse skin incision ( fig .
when the tip of the blade touches the calcaneus , the blade is slowly turned 90 medially and the medial 1/2 of the tendon is incised ( or a lateral 1/2 incision could be used when necessary , such as in the planovalgus with short achilles tendon ) .
extra cautions must be taken to prevent damage to the tibialis posterior nerve and vessel and to the flexor hallucis longus tendon , which passes near the medial malleolus .
the excessive advancement of the blade medially would increase the risk of damage to the neurovascular bundle .
a small retractor is placed under the deep fascia and paratenon , and the ankle is dorsiflexed to advance the cut more proximally and to provide tension in the tendon , so the surgeon could feel when the tendon is completely cut .
after 3 cm to 4 cm of a longitudinal cut proximally for mild to moderate equinus in children or 5 cm to 6 cm for moderate equinus in adolescents , the scissors are slowly turned laterally and the lateral 1/2 of the tendon is cut .
extra caution is needed in order to prevent damaging the sural nerve . a thumb ( fig .
4 ) was placed over the tip of the surgical scissors to prevent them from advancing beyond the lateral ( to protect the sural nerve ) or medial border of the tendon .
if unable to perform a dorsiflexion of the ankle after the proximal lateral cut , the plantaris tendon needs to be rechecked because it may not have been cut when the distal medial incision was done .
when deformity is severe , the second and the third proximal longitudinal incisions of the tendon are made to create a longer lateral strip .
the amount of lengthening required is determined with the medial and lateral strips of the tendon , held side by side with the thumb forceps while applying moderate tension after the ankle has been maximally dorsiflexed once or twice ( fig .
, the level of the distal end of the medial strip , which is displaced proximally following the maximal ankle dorsiflexion , is marked on the lateral strip with the ankle in the neutral position ( fig .
6 ) . a simple 2 layer , anterior and posterior suture technique is used .
the first is from the anterior side of the tendon , starting the suture and burying the knot inside the tendon ( fig .
the consistent suturing is important to prevent a palpable lump on the skin after the surgery , especially on the posterior aspect of the tendon .
step 6 . for the accurate suturing of the paratenon and fascia , it is important to identify them clearly .
the first stitch has to be done carefully to avoid suturing these two structures together with the achilles tendon located below them .
the suture binds the paratenon and the deep fascia together , and then a subcutaneous skin suture is applied .
a short leg cast with the ankle at 90 is applied for 6 weeks in the patients under 10 years of age . for additional protection , either a second short leg cast or an ankle foot orthosis
is applied for 4 to 6 weeks in the patients over 10 years of age .
the gentle active and passive ankle dorsiflexion and heel lifting exercises are gradually recommended after immobilization .
we evaluated the dorsiflexion angle of the ankle before the surgery and at the latest follow - up .
the time under anesthesia for the lengthening procedure and any of the postoperative complications were also noted .
the surgical results were evaluated using the american orthopaedic foot & ankle society ( aofas ) ankle - hindfoot scale .
in addition , to evaluate the patients ' satisfaction regarding the surgical scar , we allotted another 10 points to the cosmesis of surgical scar ( fig .
the mean time under the anesthesia was 30.6 minutes ( range , 20 to 40 minutes ) ; the actual duration of the surgery was approximately 15 - 20 minutes .
all of the patients showed improvement in gait pattern and they showed satisfactory cosmetic results .
the mean aofas score improved from 56.1 to 81.8 . within this group of patients , those with neuromuscular or other disorders showed low aofas scores , which improved from 42.3 to 67.1 , compared to those with idiopathic achilles tendon tightness , which improved from 69.9 to 96.5 .
as for the patients ' satisfaction with the transverse skin incisions , the mean score was 7.2 points out of 10 points ( fig .
no patients had complications such as the tendon adhesion , total transection , excessive lengthening ( calcaneus deformity ) , or neurovascular damage .
the recurrence of the tendon shortening was noticed in 4 ankles of the 2 cerebral palsy patients , and the second lengthening procedures were performed through the same incisions .
the recurrence and other complications were noted for all 3 techniques ( table 1 ) .
our new technique attempts to take the best points from both the percutaneous sliding lengthening and z - lengthening ( with a medial longitudinal incision ) techniques .
the mean time under the anesthesia was 30.6 minutes ( range , 20 to 40 minutes ) ; the actual duration of the surgery was approximately 15 - 20 minutes .
all of the patients showed improvement in gait pattern and they showed satisfactory cosmetic results .
the mean aofas score improved from 56.1 to 81.8 . within this group of patients , those with neuromuscular or other disorders showed low aofas scores , which improved from 42.3 to 67.1 , compared to those with idiopathic achilles tendon tightness , which improved from 69.9 to 96.5 .
as for the patients ' satisfaction with the transverse skin incisions , the mean score was 7.2 points out of 10 points ( fig .
no patients had complications such as the tendon adhesion , total transection , excessive lengthening ( calcaneus deformity ) , or neurovascular damage .
the recurrence of the tendon shortening was noticed in 4 ankles of the 2 cerebral palsy patients , and the second lengthening procedures were performed through the same incisions .
the recurrence and other complications were noted for all 3 techniques ( table 1 ) . our new technique attempts to take the best points from both the percutaneous sliding lengthening and z - lengthening ( with a medial longitudinal incision ) techniques .
the achillles tendon has three sources of blood : the posterior tibial artery in the distal section , the peroneal artery on the mid - section , and the posterior tibial artery in the proximal section.15,17,18 ) the arteries of the achilles tendon and its paratenon are oriented in three directions : longitudinal , transverse , and deep . in most cases ,
the larger arterial branches run on the surface of the tendon transversely , perpendicular to the direction of the tendon fibers .
our transverse distal incision is made on a natural skin crease , with its length from 1.0 cm to 2.0 cm depending on the size of the patient .
compared to the longitudinal incision , this minimizes the risk of damaging the arterial vessels running transversely on the posterior surface .
the anatomical structures at the risk of damage , with our technique , are the posterior tibial nerve , the artery located in the posteromedial area of the ankle , and the sural nerve located laterally from the achilles tendon . at the level of the ankle joint in an adult ,
the posterior tibial nerve is located at an average of 11.8  2.4 mm and the posterior tibial artery at 16.7  3.8 mm , both anterior from the achilles tendon.19 ) these structures are , on average , less than 1 cm from the nearest margin of a given percutaneous triple - hemisection in the adult.11 ) the sural nerve crosses the lateral border of the tendon at an average of 9.8 cm ( range , 7 to 16 cm ) from the calcaneus in the adult.20,21,22 ) all of these distances are shorter in children .
first , a small retractor is placed at the medial side of the tendon when the blade is turning 90 to cut the medial 1/2 of the tendon at the distal insertion site .
second , the thumb or the middle finger tip , depending on which hand the physician uses to support the patient 's lower leg , is placed at the lateral margin of the tendon when the proximal lateral cut is performed .
this will prevent the further advancement of the surgical scissors ' tip toward the lateral side , so the damage of the lateral sural nerve can be avoided .
it is difficult to quantify the amount of corrections required.7,23 ) with our technique , preservation of the peritendinous attachments in the proximal tendon prevents the excessive proximal migration of the medial or lateral strips of the tendon , even with the maximal dorsiflexion of the ankle after z - lengthening , because only the posterior aspect of the tendon is exposed transversely .
the foot is maximally dorsiflexed several times and then positioned in neutral , while the tendon is sutured under a moderate tension obtained by thumb forceps on both halves of the tendon .
the toe flexors are carefully examined at the same time as the maximal ankle dorsiflexion to see whether they are also contracted .
the flexor lengthening was performed when it was indicated , such as the flexor tenotomy at the proximal interphalageal joint in muscular dystrophy and trauma patients , and the tendon recession in the toe flexor and tibialis posterior at the level of the musculotendonous junction in cerebral palsy patients .
our technique can provide the medial and lateral strips of the sufficient lengths with a single incision in the mild to moderate ankle equinus .
it is desirable to have more than 1 cm in children or 1.5 cm in adults of overlap of the medial and lateral strips for a firm side by side suture with adequate correction .
even suturing with the knots buried inside the tendon is essential to produce a smooth posterior surface . in a cross - section of the achilles tendon ,
the insertion of the tendon is flat and spread - out as it attaches to the tuberosity of the calcaneus , while the midsection is oval shaped and is narrower than its insertion and the origin.15 ) therefore , the partial excision of the thickened part of the distal tendon stump to match the proximal side is necessary to avoid a palpable lump after the suture .
it is also important to suture the paratenon and the deep fascia together with the knot buried in the soft tissues , using an absorbable suture material .
a special care must be taken with the first suture to avoid suturing these structures with the underlying achilles tendon .
also , the suture should be even without crumpling the skin . in the case of a severe equinus deformity ,
we apply a cast with the ankle in a mild equinus position while making sure there is an adequate vascular supply in the skin .
one week after the surgery , when the skin circulation is satisfactory , a second cast with the correct ankle position is applied .
we also adopt the ilizarov gradual correction technique to correct a severe ankle equinus deformity . for this , before application of the ilizarov external fixator , we use 2 or 3 transverse incisions and lengthen the tendon through the second and third incisions without suturing from side to side
. the lengthened tendons gradually slide against each other until the deformity is corrected with the ilizarov apparatus .
the short leg cast after 4 weeks of the complete correction and the ankle foot orthosis during the night provide a good result and prevent recurrences , especially for the patients with neuromuscular disorders , club foot , and trauma .
the correction happens quickly , without any significant pain or discomfort to the patient as the tendon lengthens .
none of our patients , even those with severe deformity , have shown any skin problems due to the tension .
we retrospectively studied the results of our new technique and compared them with the results of two other techniques we have used before .
the patient attributes , which include the number of patients , ages , causes , severities , etc . , are not the same for the different techniques .
our new technique seems to have a low rate of recurrence of equinus deformity ( 4 of 95 feet ) at the medium - term follow - up , compared to the other approaches ; and no patient with a crouch gait resulted from the over - lengthening .
we believe that this was due to the short skin incisions , the preservations of the paratenon and the deep fascial tube , and the use of z - lengthening rather than the open or percutaneous sliding lengthening or lengthening the aponeurotic tendon of the gastrocnemius . with the new approach
, we had fewer patients complaining of the pain compared to those who were operated with a longitudinal skin incision .
the cases of recurrence were mostly limited to the cerebral palsy patients , who were less than 5 years old at the time of surgery , and they appeared at least 3 years after the surgery .
although the range of the passive dorsiflexion was decreased during the period of rapid growth in these children , any recurrent equinus was easy to treat because there was little scarring at the operation site .
in summary , our technique of achilles tendon lengthening has proven to be an improvement over the other techniques we have employed , in terms of surgical time , tendon healing , and complication rates .
this is perhaps due to the small skin incision and the conservation of the paratenon and the deep fascia .
 backgroundthe risk of various complications after achilles tendon lengthening is mainly related to the length of surgical exposure and the lengthening method . 
 a comprehensive technique to minimize the complications is required.methodsthe treatment of achilles tendon tightness in 57 patients ( 95 ankles ) were performed by using a short transverse incision on a skin crease of the heel and by z - lengthening of the tendon . in the severe cases , two or three transverse incisions were required for greater lengthening of the tendon , and a serial cast or ilizarov apparatus was applied for the gradual correction . 
 the results of these 95 ankles were compared to those of 18 ankles , which underwent percutaneous sliding lengthening , and to the 19 ankles , which received z - lengthening with a medial longitudinal incision.resultsthe functional and cosmetic satisfaction was achieved among those who underwent the tendon lengthening with the new technique . 
 the mean american orthopaedic foot & ankle society ( aofas ) score improved from 56.1 to 81.8 . 
 the second operations to correct recurrence were performed in the two cerebral palsy patients.conclusionsthe new technique has a low rate of complications such as scarring , adhesion , total transection , excessive lengthening , and recurrence of shortening . 
 the excellent cosmesis and the short operation time are the additional advantages . 
METHODS
Surgical Technique
After Treatment
Assessment of Results
RESULTS
Results of Z-lengthening of the Achilles Tendon with a Transverse Skin Incision
Comparison with Percutaneous Sliding Lengthening and Z-lengthening with a Medial Longitudinal Incision
DISCUSSION