Limb lengthening by physeal distraction

I evaluated 10 consecutive lengthenings through the upper tibial physis in 9 patients. A bilateral frame consisting of two small-sized Wagner devices and two pairs of 4-mm transfixing pins with 5-mm-diameter central threads were used. The median lengthening was 6.7 cm. Complications were frequent. The risk of a growth disturbance is very high, and physeal distraction should therefore only be applied towards the end of the growth period.     

Limb lengthening by epiphyseal distraction

Summary Limb lengthening has been obtained using the technique of epiphyseal separation-distraction, initially in animal experiments and subsequently in operations on twenty-six human patients. The increase of length obtained ranged from 5–11 cm in the tibia and femur.There was no need for osteotomy, internal osteosynthesis, or bone grafting. The quality of the new bone formation was good and there have been no secondary fractures at the site of lengthening.

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Résumé Les auteurs ont réalisé l'allongement des membres inférieurs par une technique de «séparation-distraction épiphysaire», d'abord chez l'animal, puis chez l'homme. Vingt-six interventions ont été pratiquées. Le gain de longueur obtenu est compris entre 5 et 11 cm, tant au tibia qu'au fémur.Ce procédé ne nécessite ni ostéotomie, ni ostéosynthèse, ni greffe osseuse. L'os néoformé est de bonne qualité et il n'y a eu aucune fracture secondaire au niveau de l'allongement.

     

Long-term results of lower limb lengthening by physeal distraction

Of the many methods of limb elongation, lengthening by physeal distraction is among the newest. The goal of this study was to estimate the long-term results of femoral and tibial lengthening by epiphyseal distraction. The authors examined 40 patients who underwent 24 femoral and 16 tibial lengthenings. The average follow-up period was 9.6 years. An average of 4.6 cm of femoral lengthening and 4.7 cm of tibial lengthening was achieved. The femoral healing index was 38.1 days/cm and the tibial healing index was 35.7 days/cm. After lengthening the epiphyseal cartilage started to function in all patients, and premature growth cartilage fusion was not observed during follow-up. Complications occurred in eight patients during femoral lengthening and in four during tibial lengthening. The authors suggest that physeal distraction is a good method for moderate and simple limb lengthening. Particular care should be applied to knee joint function, especially during femoral lengthening.     

Limb lengthening by callus distraction (callotasis)

Callotasis is a new technique of limb lengthening involving slow distraction of the callus formed in response to a proximal submetaphyseal corticotomy. Using a dynamic axial fixator with telescoping capabilities, distraction begins after 2 weeks. When the required length is attained, the fixator is held in the rigid mode until radiographic evidence of callus is observed. The locking screw is then released, and dynamic axial loading is instituted to promote corticalization. One hundred bony segments have been lengthened; 50 patients had limb length inequality, and 23 had achondroplasia. The mean lengthening achieved was 22% (maximum, 58%). There were 14 complications (14%).     

Breaking bony bridges by physeal distraction

Summary Physeal distraction for breaking bony bridges and the late treatment of long bone deformities in children near maturity, has been used in our Department since June, 1983. In all cases (4 bones in 3 patients) a deformity was present at the extremity of a long bone due to a bony bridge caused by a previous injury to the growth cartilage. The results were excellent and in our opinion there are advantages over other methods. The operation itself is not extensive and very little damage is done. There is no need for internal fixation or bone grafts. It is possible to obtain lengthening and to adjust the angular correction during treatment.We conclude that it is possible to correct angular deformities and bone shortening due to bony bridges by physeal distraction without the need for resection of the bony bridge. At present we recommend this method in children near skeletal maturity, especially in those cases with bone shortening.

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Résumé Nous avons eu recours depuis Juin 1983 à la distraction épiphysaire pour rompre les ponts osseux et pour le traitement ultérieur des déformations des os longs chez les enfants en fin de croissance. Dans tous les cas (4 os chez 3 malades) il existait une déformation de l'extrémité d'un os long due à un pont osseux résultant d'un traumatisme antérieur du cartilage de conjugaison. Les résultats ont été excellents et à notre avis cette méthode présente de nombreux avantages par rapport aux autres. L'opération elle-même est peu agressive et n'entraîne que très peu de dommages. Elle ne nécessite ni matériel de synthèse ni greffe osseuse. Elle permet d'obtenir un allongement et de rectifier la correction d'une angulation au cours du traitement.Pour conclure nous estimons qu'il est possible de corriger les déformations axiales et les raccourcissements dus à un pont osseux par la distraction épiphysaire, sans qu'il soit besoin de réséquer le pont osseux. Nous recommandons cette méthode chez les enfants en fin de croissance, notamment dans les cas qui comportent un raccourcissement osseux.

     

Limb lengthening with a fully implantable mechanical distraction intramedullary nail

AIM: The morbidity of fixator-assisted distraction osteogenesis should be reduced by intramedullary lengthening devices. The ISKD (intramedullary skeletal kinetic distractor) is a new, fully implantable mechanical lengthening nail. In a prospective cohort trial the possibilities and limitations of the device used on femur and tibia are examined. METHODS: 22 patients with a mean age of 25 (range: 16-46) years were treated with an ISKD for femoral (n = 16) and tibial (n = 6) lengthening. The average leg length discrepancy was 48 (range: 25-80) mm. The follow-up was 21 (range: 7-37) months. Clinical and radiological results and complications were evaluated. RESULTS: The results of femoral and tibial applications of the ISKD are different. At the tibia, in three patients a pseudarthrosis occurred and slow callus formation was observed twice. An equinus contracture became evident in 2 patients. At the femur, in one case the lengthening was not accomplished with the device. Five patients were manipulated under anaesthesia at least once to achieve the aim of distraction. Three of these patients received retrograde implantation of the ISKD. An infection or interlocking screw failure was not observed either at the femur or the tibia. CONCLUSION: The ISKD reduces fixator-associated problems but incorporates its own difficulties which are mainly based on the guidance of the device. Careful patient advice in monitoring the lengthening process is mandatory. At the femur 8 cm of lengthening can be achieved but the nail tends to "block". Proper reaming and osteotomy techniques are important. A lengthening of more than 1 mm/day is recommended to prevent early consolidation. At the tibia weak callus formation and soft tissue contractures occur, therefore not more than 4 cm lengthening should be planned, the distraction speed has to be reduced noticeable below 1 mm/day and the initial immobilisation should be for more than a week.     

Attempted limb lengthening by physeal distraction. Continuous monitoring of an applied force in immature rabbits

The effectiveness of physeal distraction in stimulating bone growth in animals was investigated by force applied to the distal femoral growth plate of immature rabbits. The system was continuously monitored to detect physeal separation. A distraction of 0.25 mm every 12 hours led to physeal separation in five animals. One animal given a 6-kg force and two of seven given a 4-kg force showed physeal separation. All four rabbits given a 2-kg force and five of seven given a 4-kg force did not show a greater increase in length than the control femurs. Bone growth was not stimulated by physeal distraction. Any increase in length of more than the normal growth is attributable to physeal separation.     

Limb lengthening by epiphyseal distraction. An experimental study in the caprine femur

Epiphyseal distraction of the left distal femur was accomplished in 10 goats (aged 3-4.5 months). A modified Hoffmann external fixation device was used as a unilateral distraction frame. A distraction rate of 1.5 mm/day was applied for 5.5 weeks. Epiphysiolysis occurred after 3-7 days of distraction. After the lengthening procedure, the growth plate had reduced in height in eight animals on radiographic examination. In two animals the growth plate was fused. Three animals were killed at 4 (Group 1) and 8 (Group 2) weeks and four animals at 16 (Group 3) weeks after the end of the distraction period. The gain in leg length obtained by distraction was reduced owing to growth retardation in the distal femur of the operated limb. The average final lengthening was 24.9, 19.4, and 13.4% in Groups 1, 2, and 3, respectively. Femur and tibia from both sides were tested mechanically in torsion. Only one femur fractured in the elongation area. All but one elongated femur fractured in the area of the diaphysis subjected to distractional force. The torsional strength of the elongated femur compared with control was reduced to approximately 50% in all groups. The corresponding torsional strength of the tibia on the elongated extremity compared with control was reduced to approximately 75% in all groups. The difference in relative strength of femur compared with that of tibia was statistically significant. This finding can be explained by a stress-protective effect on the femur in the distraction area caused by the external device.     

Limb lengthening by callus distraction: Complications in 53 cases operated 1980-1991

We reviewed our first 53 lengthenings performed in 45 patients with an average age of 19 years at the time of lengthening. The shortening was congenital in 16 patients, post-traumatic in 15 and had various causes in the 14 remaining. 31 femurs and 22 tibias with an average shortening of 6 and 5 cm, respectively, were lengthened 6 (2-14) cm. The aim was achieved in all but 4 patients, where lengthening had to be discontinued due to complications.

Potential complications of lengthening can be numerous but, if recognized, can in most cases be dealt with during the extended lengthening procedure. 38 cases of pin-tract infections healed with antibiotics. Restricted motion in one or more joints was registered in 49 cases during lengthening; minor restriction of joint motion persisted in 14 patients. 28 cases had angular deviations during lengthening. After additional surgery all but 10 could be corrected. 4 fractures occurred after removal of the external fixator. The total number of complications was 146, and of these 76 were minor, 42 moderate and 28 severe. 36 of the 42 patients available to follow-up were satisfied with the results of the lengthening procedure.     

Digital lengthening by gradual distraction

The authors report their experience of digital lengthening and analyze the indications and results of 12 cases performed over 13 years in the plastic and reconstructive surgery service of the Kassab institute. Distraction was performed using a mini-orthofix device. In majority of cases, the procedure was performed on young people, manual workers and victims of industrial accidents. The lengthened osseous segment was the 1st metacarpal in 7 cases, the proximal phalanx of the index in 3 cases, the 3rd metacarpal once and the proximal phalanx of the middle finger in one case. Gradual distraction at the rate of 0.25 to 0.5 mm/day was carried out in 10 cases using the procedure of "callotasis". In 2 cases the distraction was performed at a rate of 1 mm/day followed by bone graft. Callotasis allowed us to obtain an average lengthening of 17 mm (61.5%) in distraction of the phalanx, and 26 mm (63.3%) in distraction of the first metacarpal. This technique avoids the spontaneous shortening observed after the use of bone graft alone. Complications are relatively frequent but had little influence on the final result.     

Bone lengthening by physial distraction

Summary Experimental physial distraction was carried out in the distal part of the femur in 45 two-month old lambs in order to study the basic mechanisms of lengthening as ell as the viability of the growth cartilage after using this method. The animals were divided into three groups (A, B and C), and each group into three subgroups (1, 2 and 3) according to the rate of distraction used (2 mm/day, 1 mm/day, 0.5 mm/day) and the time of sacrifice.The results obtained show that the basic lengthening mechanisms consists, firstly, in the production of a fracture between the metaphysis and the epiphysis and, secondly, that the lower the distraction speed employed, the greater is the short-term and long-term viability of the growth cartilage. Optimum viability was observed at a distraction rate of 0.5 mm/day.On this basis we conclude that in clinical practice physial distraction could be indicated for children at an early stage of skeletal growth and repeated later provided that the rate of distraction is kept within reasonable limits.

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Résumé Une étude expérimentale portant sur la distraction épiphysaire au niveau de l'extrémité distale du fémur a été réalisée chez 45 moutons âgés de 2 mois, dans le but d'étudier les mécanismes d'allongement ainsi que la vitalité du cartilage de croissance. Les animaux ont été divisés en trois groupes (A, B, C) et 9 sous-groupes (1, 2, 3) selon la vitesse de l'allongement (2 mm/jour, 1 mm, 0,5 mm) et la date à laquelle ils ont été sacrifiés.Les résultats obtenus montrent que le mécanisme de base consiste dans la création d'une fracture épiphysodiaphysaire et, d'autre part, que plus la vitesse d'élongation est lente, plus le cartilage de croissance est viable à court et à long terme. Les meilleurs résultats furent obtenus à la vitesse de 0,5 mm/jour. On peut donc conclure qu'en pratique la distraction épiphysaire peut être indiquée chez les enfants dont l'âge osseux est bas, et qu'elle peut être répétée ultérieurement, à condition de maintenir la vitesse d'allongement dans des limites raisonnables.

     

Tibial lengthening by epiphyseal distraction

Tibial lengthening by slow distraction of the distal epiphysis using the dynamic axial fixator was performed in 3 patients near to skeletal maturity, in 2 patients with congenital origin and in one with achondroplasia. The obtained lengths were 4.4 cm (17% of the tibial length), 3.7 cm (12%) and 3.6 cm (19%). There were no serious complications. Bone formation at the site of distraction was thought to be periosteal in origin when assessed using X-rays and computerized tomography. There was no radiological evidence that bone at the distracted sites was formed by an apposition from the metaphyseal side which is expected in cases of stimulation of endochondral ossification in the growth plate. There was no further measurable growth at the distracted growth plates after lengthening. This method is useful for limb lengthening near the time of epiphyseal closure.     

Chondrodiatasis-controlled symmetrical distraction of the epiphyseal plate. Limb lengthening in children

We describe a technique for slow, progressive, symmetrical distraction of the growth plate using a lightweight dynamic axial fixation system. Results are given for the elongation of 40 bony segments in children with limb-length discrepancies and 60 segments in children with achondroplasia or hypochondroplasia. Increases in limb length of up to 36% were obtained in non-achondroplastic and up to 64.5% in achondroplastic patients. There were no nerve or vascular lesions or bony infections and no case required a bone graft. Pin-track complications occurred in only 1.5%.     

Limb lengthening by low rate epiphyseal distraction. An experimental study in the caprine tibia

Low-rate epiphyseal distraction of the left proximal tibia using a modified bilateral Hoffmann external fixation device, was accomplished in 14 goats (age 6-7 months). Daily distraction at a rate of 0.5 mm was continued for 5.5 weeks. Epiphysiolysis occurred after 5-9 days. After distraction had been discontinued, the external device was left in situ for fixation for 4 weeks. The animals in group 1 (n = 6), group 2 (n = 3), and group 3 (n = 5) were killed at 4, 16, and 32 weeks, respectively, from the end of the distraction period. The proximal growth plate of the elongated tibia appeared radiolucent at the conclusion of the study but was less distinct and reduced in height as compared with the control leg. The gained length at the end of the distraction period was on the average 2.2 cm (11.9%). This gain in length was reduced with further growth. In group 3, the final gain in length was reduced to half. A reduced cortical thickness of the bone within the area subjected to distractional force was observed. This finding is attributable to stress protection. An interesting observation comparing control and operated tibia was an increase of the cross-sectional diameter of the elongated bone. Both tibiae of all animals were tested mechanically. The torsional strength of the elongated tibiae as compared with controls was on the average 29% in group 1, 79% in group 2, and 95% in group 3. We conclude that leg lengthening by low-rate epiphyseal distraction in the proximal tibia is a justifiable alternative to other lengthening procedures in individuals approaching adolescence. In juveniles, lengthening by epiphyseal distraction may result in reduction in the longitudinal growth.     

Correction of angular deformities by physeal distraction.

Physeal distraction is an alternative to more conventional treatments for the correction of angular deformities of the long bones. Twenty deformities of the femur and tibia, nine of which also involved associated shortening, were partially or completely corrected. In eight cases, there was physeal bony bridge. Complete correction of the angular deformity was achieved in 17 patients, and in seven patients, more than 80% correction was achieved. There were complications in four patients that hindered complete correction of the deformity, or shortening, or both. The external control of the correction until consolidation occurs is progressive and fairly noninvasive. The method allows external control of the correction until consolidation; it acts at the site of the deformity itself and permits lengthening and angular correction during therapy. In deformities with a physeal bony bridge, correction can be achieved with physeal distraction alone, prior resection of the bridge is not unnecessary. The technique is indicated in cases of angular deformities in patients nearing skeletal maturity and particularly in subjects in whom there is associated shortening.     

Metacarpal distraction lengthening

Metacarpal osteotomy and distraction lengthening is an excellent method of treating patients with multiple digit aplasia, metacarpal hypoplasia, and some types of digit amputation. The authors describe their technique and the results obtained in 24 patients operated on for 41 metacarpals.     

Limb lengthening by epiphyseal distraction in chondrodystrophic bone: an experimental study in the canine femur

Epiphyseal distraction of the left distal femur was accomplished in 18 chondrodystrophic dogs (age 19-22 weeks). A distraction rate of 0.5 mm/day was applied by means of a unilateral device. Epiphysiolysis occurred after 4 to 9 days. Lengthening was continued for 3 weeks. The animals were killed at 3 (Group 1; n = 5), 19 (Group 2; n = 10), and 71 (Group 3; n = 3) weeks after the end of distraction to verify the magnitude of elongation at removal of the device (Group 1) and at the time of growth cessation (Groups 2 and 3), and to register possible permanent secondary joint changes (Group 3). The average lengthening of 1.2 cm (12.3%) at removal of the device was reduced to 0.7 cm (6.4%) at cessation of growth. The middiaphyseal diameter of the elongated femur was enlarged after the lengthening procedure in all animals. The average torsional strength of the elongated femur compared with the contralateral control was 83% in Group 1, 98% in Group 2, and 107% in Group 3. Degenerative changes were observed in the knee joints of three animals in each group. A two-way analysis of variance was applied for all data sets to test differences between control and elongated bones and between time periods. The reduction in gained length by retardation of residual growth in the distal femur was significant (p less than 0.05). The difference in external diameter between lengthened and control bones was significant in Groups 1 and 3 (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Limb lengthening with epiphyseal and callus distraction using the Wiesbaden ring fixator]

Treatment of unequal leg-length can either be operative or conservative. The historical development and devices for ring fixation are discussed. The surgical technique is described in detail along with the post-operative care in cases of epiphyseal distraction and callus distraction with a ring fixator. The article closes with the advantages of the method and its possible complications.