Treatment for congenital synostosis of the fourth and fifth metacarpals with the hemicallotasis technique

The hemicallotasis technique was used to treat the fifth metacarpal in a hand with congenital synostosis of the fourth and fifth metacarpals. Lengthening and correction of the metacarpal were achieved simultaneously. Continuous traction eliminated further soft-tissue procedures. The appearance and function of the hand were much improved.

Maxillary-midface distraction in children with cleft lip and palate: a preliminary report

A miniature system of distraction devices has been employed for maxillary-midface advancement in two children with cleft lip and palate, class III malocclusion, and associated midfacial hypoplasia. The devices are made with commercially available palatal expansion screws linked to rigid fixation plates. A midfacial osteotomy is used, and distraction is begun on the third postoperative day. In the first child, a 7-year-old boy, the midface was distracted 11 mm sagittally and 4 mm inferiorly. In the second patient, a 4 1/2-year-old girl with unilateral cleft lip and palate and midfacial retrusion, an 11-mm distraction was carried out in the vertical and sagittal direction. There were no complications, and none of the devices failed. Maxillary-midfacial distraction osteogenesis to correct severe maxillary-midfacial hypoplasia in children with clefts and other craniofacial disorders permits early intervention with potentially less invasive techniques than are currently available.

Mechanical characterization of a totally intramedullary gradual elongation nail

An intramedullary gradual elongation nail (Albizzia) capable of fulfilling the function of traditional intramedullary nails while providing the gradual, controlled distraction of an external fixator was designed for progressive lengthening of lower limbs. In this study, the biomechanics of the gradual elongation nail were compared with several intramedullary nails: Grosse & Kempf, Russell-Taylor, AO, and Laffay. Bending stiffness, torsional stiffness, ultimate bending strength, and torsional strength were determined using the American Society for Testing and Materials standard F383-73 as a guide. The results show that in unextended and elongated conditions, the gradual elongation nail has torsional stiffness (1-5 Nm2) comparable with the AO nail (2 Nm2) and bending stiffness (41-89 Nm2), ultimate bending (246 Nm), and torsional (28-37 Nm) strengths within the ranges obtained for other intramedullary nails (27-105 Nm2, 167-298 Nm, and 2-100 Nm, respectively). Additionally, the low torque required to lengthen the device under a 500 N load (3 Nm) and the low longitudinal stiffness because of the active dynamization system with bimodal load deformation characteristics (80-120 N/mm initial, 600-800 N/mm secondary) produce a device with almost no torsional and longitudinal stress shielding. From a biomechanical point of view, this single, completely implantable device is a safe, viable, and efficacious alternative to external fixation for progressive lengthening of lower limbs.

The use of frozen-allograft radial head replacement for treatment of established symptomatic proximal translation of the radius: preliminary experience in five cases

Five patients with disabling symptoms related to proximal translation (> 1 cm) of the radius following radial head excision (Essex-Lopresti lesion) were treated with implantation of a frozen-allograft radial head prosthesis. Following restoration of neutral ulnar variance at the wrist, a size-matched frozen radial head allograft was implanted and secured to the proximal radius with internal fixation. In three patients, this was a two-stage procedure; radial length was restored gradually using an ilizarov external fixation device and the allograft was placed later. Patients were evaluated clinically and radiographically at a mean follow-up time of 3 years (range, 1-7 years). All patients had relief of wrist and elbow pain and were satisfied with the outcome of the operation. Forearm rotation improved by a mean of 37 degrees and wrist motion improved by a mean of 45 degrees. Forearm reconstruction with frozen radial head allograft implantation may be a beneficial method of treatment for this difficult problem.

Distraction osteogenesis to widen the mandible

The purpose of this investigation was to elucidate the biology of distraction osteogenesis during mandibular widening. Midsymphyseal vertical interdental osteotomies were performed in nine Macaca mulatta monkeys. After a latency period a tooth-borne appliance was activated at a rate of 0.5 mm twice a day for 7-10 days. The appliance was then stabilized for a period of 4 or 8 weeks. The distraction gap at the inferior portion of the symphysis was bridged completely by new bony trabeculae. Bone formation in the interdental area was apparently related to the surgical technique. Newly formed bony trabeculae were oriented parallel to the direction of distraction. The location of the osteotomy site with an adequate margin of alveolar bone contiguous with the adjacent teeth was necessary for the induction of the distraction osteogenesis. Disproportional movement between superior and inferior portions of the distracted segments was noted.

[Unilateral stepwise lengthening osteotomy of the femur]

Intraindividual length differences up to 1.2 cm in femora, up to 1.0 cm in tibiae and up to 1.4 cm in whole leg length can be regarded as physiological. Length differences in childhood are frequently compensated for by functional adaptation in the chain of adjacent limbs. In adults, however, that adaptability is diminished and correction osteotomy after post-traumatic shortening may therefore be indicated more generously dependent on local and general criteria of operability. A conscientious analysis of bone geometry by clinical means, radiology and computed tomography is mandatory for the indication and planning of any correction osteotomy. Intraindividual leg length differences of more than 4 cm are preferentially treated by continuous callus distraction techniques. Shortening by less than 4 cm, however, is suitable for a one-stage stepwise prolongation osteotomy in the metaphysis of the femur, i.e. in the subtrochanteric or supracondylar region. These osteotomies are than stabilized by long condylar plates; the bony defects are filled up by auto- or allogenous corticospongeous bone. Simple modifications of the stepwise prolongation osteotomy permit additional corrections of torsional deviations up to 20 degrees or of axial deviations in the frontal or sagittal plane up to 5 degrees. The results of 24 one-stage stepwise prolongation osteotomies of the subtrochanteric and supracondylar femur after congenital or post-traumatic shortening are presented as well as the reason and respective therapies for three important complications.

Reactive changes in the temporomandibular joint after mandibular midline osteodistraction

The purpose of this study was to evaluate the histologic changes within the condyle in response to mandibular widening using osteodistraction. Mandibular midline osteotomies were made in nine Macaca mulatta monkeys and tooth-borne distraction devices were bonded to the mandibular dentition. Distraction was continued until a 3-5 mm widening was achieved. The appliances were then stabilized for a period of 4 weeks. Non-decalcified sagittal sections of the lateral, middle and medial thirds of the condyles were analyzed. Although three of the seven animals showed no unusual morphology, four others exhibited morphologic differences within the fibrous layer, cartilage layer or bone/cartilage interface. Histologic changes were seen to occur in the fibrous layer, cartilaginous layer and cartilage/bone interface. The severity of these changes were correlated with the likely rotational forces directed at the condyle on the postero-lateral and antero-medial surfaces.

[Callus distraction for progressive lengthening of the capitate bone after resection of the lunate bone in stage III lunate malacia. Surgical technique and 1 year results]

Inspite of the excellent subjective judgement and functional results of Graner's operation in case of Kienbock's disease stage III, this technique is rarely used nowadays because of its high rate (20 to 30%) of disturbed fracture healing due to impaired blood supply. To avoid the risk of complete devascularization in the capitate region, we are using the callotaxis lengthening technique of Ilizaron, carrying out a segmental shifting. After percutaneous temporary SC- or STT-arthrodesis with the scaphoid in the horizontal or high position, the lunate is completely resected using a dorsal approach. Osteotomy of the capitate is carried out at the corpus-collum interval in order to disturb a minimum of the vascular supply to the bone. Seven to ten days postoperatively, distraction is started with a rate of 1 min/day. The desired distraction length is accomplished, when the capitate articular surface fits perfectly into the curvature of the proximal row articular surface. In order to reduce or prevent soft tissue related complications during the consolidation period, the external distractor is replaced by two percutaneous Kirschner-wires. The consolidation period takes twice as long as the distraction period. Since November 1993, fourteen patients presenting a stage III Kienböck's disease have been treated by this new technique. The operative technique, postoperative care, as well as the potential and real complications are described and illustrated by one clinical case.

Femoral callotasis

The procedure for femoral callotasis is explained, and a series of 160 lengthenings is reviewed, 60 for limb length discrepancy and 100 for short stature. Callotasis was performed in 106 subjects with a mean age of 19 years. The mean healing index (HI) of 36 days per centimeter is related more to etiology than to age or extent of lengthening. There were nine complications (15%) among subjects treated for limb discrepancies and 39 (39%) in those treated for short stature. Three permanent sequelae were recorded: necrosis of the head of the femur (two cases) and permanent extension deficit of the knee (one case). The present review assesses the type of results that can be achieved with callotasis in straightforward cases of femoral lengthening when the guidelines proposed by the author are followed. It does not attempt to compare this technique with other methods of limb lengthening.

[Long-term results of 9 cases of elongation of the ulna in treatment of Kienböck's disease]

The treatment of Kienböck's disease is currently controversial. Ulnar shortness is usually considered to be the main etiological factor. This observation is the basis for distal radio-ulnar joint levelling procedures, which means the radial shortening osteotomy and ulnar lengthening osteotomy. Several authors have reported their experience on the topic, but there are very few studies with sufficient follow-up to evaluate the value of the operative procedure on the carpus. We report a 9 patient review series following an ulnar lengthening procedure for Kienböck's disease. The average follow-up was 24 years (range: 12 to 21 years). There were 7 men and 2 women and the average age was 30 years at the time of the operation. The dominant side was affected 6 times out of 9.6 heavy workers and 3 light workers are reported. Four out of 9 patients had a history of trauma. The surgical procedure was a stair-step distal diaphyseal ulnar lengthening with distraction and osteosynthesis with a plate, without bone graft. The selected patients underwent a clinical examination of wrist pain, mobility and strength in comparison with the non-operated side. All patients under went a standard radiographical examination in neutral position. The analysis of the series shows that ulnar lengthening was successful for all patients especially on the strength and pain level, whereas mobility deteriorated. Without being able to reconstitute the normal morphology of the lunate bone, the procedure was able to stop the long-term natural course of the disease leading to carpus collapse and arthrosis without radio-carpal disturbance. Excessively long consolidation times and a very high pseudarthrosis rate are reported. Ulnar shortness does not seem to be an etiological factor. The natural history of the disease is perhaps not as bad as previously thought. The impact of the procedure on the distal radio-ulnar joint and the ulnar impaction syndrome in excessive lengthening are serious issues which need to be resolved. The procedure is preferably indicated in young patients, at the beginning of the disease, with a negative distal radio-ulnar variance. The Linscheid operative technique is recommended.

Distraction lengthening following growth cessation due to thumb replantation in a child

Growth disturbance due to premature physeal closure as a sequela of digit replantation, on occasion, can cause shortening, resulting in suboptimal function. A simple method for correction using only local tissues is possible via gradual bony distraction. This was attempted in a toddler, whose dominant thumb was amputated by a riding lawn mower when he was an infant, because replantation caused significant growth cessation. The first metacarpal distraction over 64 days netted 22 mm of lengthening. Because a further immobilization period to allow spontaneous consolidation by neo-osteogenesis was aborted at the family's insistence, a fibular autograft of that dimension was inserted into the created bony gap. Ultimately, after 24 months of follow-up, the distracted thumb had been increased 26% in length and was 88% of the length of the contralateral thumb at that time, compared to only 74% prior to initiating the distraction.

Distraction frequency and the gastrocnemius muscle in tibial lengthening. Studies in rabbits

We compared the effect of various distraction frequencies on the gastrocnemius muscle by evaluating the histological findings, intramuscular enzyme contents, and DNA contents. In 15 rabbits, both tibiae were distracted 1 mm per day. The distraction frequency was 2 steps (0.5 mm/12 hour) by hand on the right side and 120 steps (0.0083 mm/12 minutes) by an auto-distractor on the left. The rabbits were divided into 3 subgroups based on length gain: 10%, 20%, and 30%. Histologically, there were no signs of fibrosis or edema and no differences in the number of necrotic cells, and intramuscular enzyme contents between the 2- and 120-step groups. The DNA content, however, was higher in the 120-step group at 30% lengthening in the middle of the muscle belly, and at 20% and 30% lengthening in the musculotendinous junction. Our findings suggest that an increase in the distraction frequency may promote DNA synthesis in the muscle, thus providing better muscle accommodation during bone lengthening.

[Ultrasound follow-up of callus distraction of the tibia. Technique, possibilities and limits]

In a prospective study 20 patients were monitored with serial sonograms and radiographs during distraction osteogenesis at the lower limb. All sonograms were obtained in four planes using a 7.5 MHz transducer. The distraction gap was seen as a sonolucent area in all patients after corticotomy. At an average of 20.7 (14-28) days after the beginning of the distraction, echogenic foci occurred and showed increasing longitudinal alignment with further distraction. Radiographical signs of beginning mineralization were seen an average of 48.3 days after the start of the distraction. Exact measurement of the distraction gap was possible in all patients during lengthening. Bone healing complications and hematoma could be detected by ultrasound. A rapid increase of bone mineralization was seen after the distraction was stopped. With increasing cortication of the regenerate bone, sonograms showed a hyper-reflecting solid line so that further mineralization and the time of removal of the fixator could not be assessed by ultrasound. Ultrasound is more sensitive than radiography in identifying new bone formation during distraction, measuring the length of the distraction gap, and detecting early bone-healing complications and can therefore reduce the need for radiographs.

[The monorail system--bone segment transport over unreamed interlocking nails]

A treatment protocol is demonstrated, consisting of an osteotomy, either proximal or distal, of the bone defect with subsequent segmental transport via an anteromedially (tibia) or laterally (femur) mounted AO external fixation over an unreamed interlocking nail (monorail system). Twenty patients were treated by this method with indications as follows: 13 had a segmental bone defect of the tibia, 3 of the femur. Three patients showed post-traumatic and postinfectious leg-length discrepancies and one was treated for hypertrophic non-union of the femur. Defect distance varied between 5 and 18.5 cm and average time for transport was 19,42 days/ cm for the tibial shaft, 15,93 days/cm for the femur. Two patients developed deep infection, which required change of treatment, removing the monorail system and application of an Ilizarov apparatus. Despite complications using the monorail system, all patients healed and no amputations were required. The monorail system can be used as an alternative to the Ilizarov method under certain criteria of patient selection; these criteria are shown by an algorithm for segmental bone defects without infection, respecting the soft-tissue status with or without neurovascular compromise.

[Callus distraction in tibial defect fractures]

Lower leg fractures with an osseous defect can be treated effectively with the callus distraction technique by Bier-Ilizarov. Because osteocytes are cultivated at the site of the defect, a real biological system is working-in contrast to other methods. Especially in lower leg fractures with a denuded tibia, the technique of primary shortening to cover the soft-tissue defect with subsequent compensatory lengthening by callus distraction is valuable. This technique does not need special hospitals but skillful surgeons. A closed surgeon-patient relation ship is required because most treatments are done on an outpatient basis. The cosmetic and functional results are good.

[The value of ultrasonographic monitoring in mandibular lengthening using the Ilizarov principle. Preliminary results]

From a review of the literature and a clinical case, we demonstrate the value of ultrasonographic monitoring of mandibular distraction according to the Ilizarov's protocol. Unlike X rays, sonography offers early and reliable pictures of the ossification process. The ultrasonic image matches the histological aspect obtained in the course of experiment. A more accurate monitoring of the regenerating area is thus made possible.

Distraction osteogenesis in the mandible with a motor-driven plate: a preliminary animal study

Distraction osteogenesis is an established method for lengthening of the mandible and for reconstruction of bony defects. We report on our first experience with a motor-driven 2.7 mm plate which was fixed at the lingual surface of the body of the mandible in Göttingen minipigs following osteotomy of the mandible. The power supply and the timer module were inserted subcutaneously in a neck pocket. A maximum distraction of 13 mm was observed. Further research is necessary before clinical application of a comparable system.

Correction of mandibular hypoplasia by means of bidirectional callus distraction

The method of gradual callus distraction proved to be very useful in augmenting hypoplastic mandibles. When performing our first series using a unidirectional distractor, we faced some problems in determining the direction of lengthening. Moreover, postoperative adjustments were not possible. On the basis of this experience, we developed a bidirectional lengthening device consisting of two limbs and a variable angulation piece. This allows distinct control of the vertical and horizontal components of the distraction. The method proved effective and reliable in 18 patients with various degrees of mandibular hypoplasia. The median follow-up period was 10 months (range, 1-19 months).

Lengthening of the lower limbs in Ollier's disease: problems related to surgery

Ollier's disease is a chondromatosis of the long bones that occurs rarely but that is highly disabling because it causes severe dysmetria and deformity of the lower limbs. Surgical correction of these skeletal changes is obstructed by poor mechanical resistance of the bone tissue affected and by the amount of lengthening required to even the lower limbs. It is the purpose of this study to indicate the surgery of choice for the treatment of this disease, comparing the two most recent methods used: Wagner's technique and the Ilizarov method. The latter is more reliable in terms of mechanical hold and the possibility of correcting severe deformities, producing bone regenerate of excellent quality even in major lengthening procedures. These results were obtained by adapting the Ilizarov method to the features of the chondromatous bone, thanks to the extreme malleability of the circular external fixator.

[Universal 3-dimensional correction and reposition with the ring fixator using the hexapod configuration]

A new configuration for the Ilisarov fixator with 6 distractors and 12 ball joints in the form of a hexapod is proposed. Using this assembly, a correction or reduction is possible with respect to any given point and axis in space. The primary position of the rings is not critical. The fixator system is statically determined and there is no stress between the longitudinal rods. Difficult corrections like those necessary for rotational deformities can be done without complicated joint mechanisms.

Mandibular lengthening by distraction osteogenesis using osseointegrated implants and an intraoral device: a preliminary report

PURPOSE

This study investigated an approach to distraction osteogenesis of the mandible using osseointegrated implants and an intraoral device.

MATERIALS AND METHODS

Five adult dogs were used for this experiment. After the extraction of the left mandibular premolar and molar teeth, two osseointegrated implants were placed. Abutment connection, attachment of the intraoral distraction device, and an osteotomy in the region between the implants were performed 3 months after implantation. The distraction was done at rate of 1 mm/day for 10 consecutive days to elongate the mandible 10 mm. The animals were killed 2, 3, and 4 weeks after the distraction was completed, and radiographic and histologic examinations were done.

RESULTS

The longer the time after completion of distraction, the more uniform the new bone that was observed radiographically and histologically in the gap created by the distraction. The titanium implants remained stable during the course of mandibular lengthening.

CONCLUSION

An intraoral device using osseointegrated dental implants can serve as a mechanism for distraction osteogenesis in the maxillofacial skeleton.

Treatment of equinocavovarus deformity in adults with the use of a hinged distraction++ apparatus

We evaluated the results following the use of the Volkov-Oganesyan-Povarov hinged distraction apparatus to correct equinocavovarus deformity of the foot in sixty-five adults (eighty-three feet). The deformity was secondary to ischemic and neuropathic changes after trauma to the foot and ankle, poliomyelitis, Charcot-Marie-Tooth disease, or untreated clubfoot. The deformity often was associated with severe neurotrophic changes, extensive scarring of the skin, callosities, or osteomyelitis of the foot, all of which usually preclude operative reconstruction. The average age of the patients was twenty-six years (range, sixteen to fifty-six years). The average duration of follow-up was ten years (range, three to nineteen years). The duration of distraction was three to thirteen weeks, and the apparatus usually was kept in place for an additional two months after the desired position of correction had been achieved. The patient then wore a plaster cast for an average of eight weeks and custom-molded shoe-inserts for at least one year. A plantigrade foot was obtained with this external transosseous distraction device. Eight patients had inflammation of pin tracks, which was treated with local injection of antibiotics into the soft tissues and application of bandages soaked in antibiotics to the area around the pin sites. The pins were removed from five of the eight patients, and the apparatus was removed from three additional patients because of osteomyelitis. The results were classified as good in fifty-nine feet, satisfactory in twenty, and unsatisfactory in four. In the four feet (three patients) with an unsatisfactory result, a good result was obtained after an arthrodesis was done.

Intraoral distraction for mandibular lengthening: a technical innovation

An intraoral distraction device for mandibular lengthening is reported. Correction of vertical deficiency of the ramus was associated with expansion of the soft tissue of the jaw, without any visible scars.

[Segmental displacement by callus distraction in extended tibial defects]

In open tibial fractures with defects over 4 cm, spongiosaplasty is considered to be insufficient. Since 1988 we have tried to apply Ilisarov's ideas of callus distraction in combination with modern external fixation devices and AO/ASIF implants. By August 1995, 15 patients with severe tibial fractures had been treated. The bone defect averaged 7 cm. Thus, more than 1 m of tubular bone was produced. Eleven male and 4 female patients, averaging 21.3 years in age, were given this treatment. The defect was caused by resection of a malignancy in 3 cases and a second- or third-degree open fracture in 12 cases, accompanied by osteomyelitis in 6 cases. Reconstruction required an average of 5.3 operations. The complication rate was 53%, and the median duration of treatment was about 1 year. The final results were excellent or good. Amputation could be avoided in all instances. This treatment is contra indicated if the patient exhibits a lack of compliance. There is a realistic chance of salvaging the limb in cases of severe soft tissue and bone defects. In terms of economical considerations, this treatment is cost effective. Physical integrity and mobility without aid is the important motivation for these patients.

Mandibular lengthening by intraoral distraction using osseointegrated implants

Mandibular lengthening by distraction osteogenesis is a new method for use in treating congenital deformities or postsurgical bone defects. However, the use of extraoral transcutaneous pins in the mandible has disadvantages, such as facial scars and facial nerve or inferior alveolar nerve injury. The purpose of this study was to establish a new approach to distraction osteogenesis in the mandible by using osseointegrated implants and an intraoral device. Ten adult canines were used for this experiment. After extraction of the teeth and placement of two titanium implants in the left mandible, connection of the intraoral distraction device to the abutments, and corticotomy in the medial portion between implants were performed. Distraction was done at the rate of 1 mm per day to elongate 10 mm in length. Radiographic and histologic examinations showed that successful mandibular lengthening was achieved. New bone was primarily formed by intramembranous ossification and partial endochondral ossification. Titanium implants placed for anchorage of the device remained stable during the course of mandibular lengthening. Study results suggest that the intraoral device using osseointegrated dental implants can be used as a mechanism for distraction osteogenesis in the mandible.

Pre-operative distraction lengthening for radial longitudinal deficiency

Patients treated for total radial aplasia have been reviewed. It was possible to re-align the carpus by radialization in five out of six limbs treated with pre-operative distraction, but in only one out of six treated without distraction. The average improvement in radial angulation in the non-distraction group was 19 degrees and in the distraction group 38 degrees. The average improvement in radial translation was 16 mm and 17 mm in the two groups respectively. Pre-operative distraction with the Kessler device permits re-alignment of the hand without skeletal resection or excessive tension on the radial neurovascular structures.

[Perspectives in callus distraction]

Callus distraction is an enrichment of the surgical orthopaedic way of reconstructing bone defects, but it is also an effective method of lengthening limbs. The biological facts correspond to our knowledge about fracture healing. Concerning apparatures, further development is needed. In certain cases the ring fixator is the method of choice, but in most indications it is not necessary. Every effort should be made to adapt modern technologies, including fully implantable systems, to the "biological method" of callus distraction, whenever possible.

Mandibular distraction osteogenesis as first step in the early treatment of severe dysgnathia in childhood

The sole orthodontic treatment of severe dysgnathias in childhood often leads to unsatisfactory results. On the other hand, standard surgical procedures are very difficult and due to their high risks not practicable in early childhood. The distraction osteogenesis enables us to correct hypoplastic mandibles, so that secondary malformations of the midfacial complex can be avoided. During the operation the hypoplastic site of the mandible is osteotomized behind the last visible tooth bud and a bidirectional distractor is inserted. Following the principles of Ilizarov the new callus is lengthened gradually until the required length of the mandible has been achieved. Out of a total sample of 27 patients 3 case reports of young children are presented. The new surgical concept describes new treatment perspectives.

[A new method for treating the Kirner deformity with the SM-Fix phalangeal distractor]

The Kirner deformity belongs to the rare bony deformities of the small finger. The present treatments range from hemiepiphysiodesis to osteotomy with bone-grafting. We present a ten-year-old girl with a unilateral Kirner deformity treated in a new fashion. Through a distal phalanx osteotomy and the use of a SM-Fix-phalangeal distractor, bridging the distal interphalangeal joint, the axis was corrected. After four to five weeks the defect was filled by callus distraction. The advantage of this method is not only the minimal traumatisation of the juvenile distal phalanx but also the functional and cosmetic results.

Distraction osteogenesis in maxillofacial surgery using internal devices: review of five cases

PURPOSE

The purpose of this report is to show the feasibility and potential advantages of using internal devices for distraction osteogenesis in the management of maxillofacial skeletal deficiencies.

PATIENTS AND METHODS

Distraction osteogenesis was used to correct a variety of maxillofacial skeletal deformities in five patients. One patient underwent bilateral Le Fort III advancement aided by distraction, three patients underwent mandibular ramus lengthening, and one patient underwent segmental alveolar reconstruction by distraction. The devices were activated by either a transcutaneous or transmucosal pin. After achievement of the desired skeletal transport, the activating pins were disengaged and removed from the distraction device. This allowed the distraction device to remain submerged and to stabilize the site of the consolidating bone.

RESULTS

All patients achieved lengthening of their jaws. However, premature consolidation was noted in two patients, and one patient had significant relapse.

CONCLUSIONS

Development of internal distraction devices is important to address the limitations of currently available biphasic systems. Potential benefits of internal devices include 1) elimination of skin scarring caused by translation of transcutaneous fixation pins, 2) improved patient compliance during the fixation or consolidation phase because there is no external component, and 3) improved stability of the attachment of the device to the bone.

Osteoplasty of the mandible by local tissues

Thirty three patients with 0.5 to 4.5 cm gunshot defects of the mandible were treated. The ends of the fragments of the bone were initially compressed, then distracted with the help of a compression-distraction device. The immature callus was distracted at a rate of 0.25 mm four times a day. During the process of distraction the defects of bone and soft tissues are replaced. Lack of soft tissue, which make insertion of a free bone graft impossible, is the main indication for an osteoplasty by local tissues.

[Factors affecting bone regeneration in Ilizarov callus distraction]

We evaluated the X-rays of 36 patients who underwent 50 callus distractions. With the aid of a computerized digitalisation system for analogue films, the relative X-ray density of the distraction area was calculated for each X-ray. These relative X-ray densities were figured graphically for the duration of treatment for each patient. In the consolidation phase, the graph of each patient had a logarithmic relationship. The gradients of the logarithmic density curves were considered an indicator of the quantity of new bone formation. These gradients were correlated to the following clinical parameters: age of the patient, beginning of distraction after corticotomy, average speed of distraction, average weight bearing during the distraction and consolidation phase, location of corticotomy (distal femur versus proximal tibia) and diclofenac medication. Except for the location of the corticotomy and diclofenac, all parameters had an influence on osteoneogenesis by callus distraction. The parameters affecting new bone formation the most were the age of the patient and weight bearing. Patients aged under 18 years (p = 0.005), beginning of distraction later than 8 days (p = 0.109), an average distraction speed below 1 mm/day (p = 0.079), and average weight bearing of more than 30 kg (p = 0.068 for the distraction phase and p = 0.089 for the consolidation phase) showed a quantitatively higher rate of new bone formation by callus distraction than the patients in the other groups. Patients with a shorter leg due to poliomyelitis and one patient with an amniotic leg tie showed a slower increase in X-ray density graphs than the other patients.

Repeated mandibular lengthening in Treacher Collins syndrome: a case report

A patient with mandibular hypoplasia associated with Treacher Collins syndrome was treated by bilateral distraction osteogenesis. Since less than optimal length was provided by the first distraction, a second corticotomy was performed in the newly formed bone 6 months after the first distraction. Thus bone gained by distraction osteogenesis was subjected to distraction once again. New bone formation occurred after the second lengthening. This case illustrated that distraction osteogenesis may be applied to the mandible at the site of previous distraction.

Ilizarov femoral lengthening in adults

From January 1990 to December 1991, we treated 12 cases of length discrepancy due to femoral inequality with the technique of Ilizarov femoral lengthening. The patients' ages ranged from 20 to 33 years (average, 28 years). Of these, nine patients were men and three were women. Corticotomy was performed either at the distal metaphysis or at the junction of distal metaphysis and diaphysis. After a latency of seven to ten days, distraction commenced at a rate 0.25 mm every six to twelve hours. Bone generation was obtained in all patients without the need of bone grafting. The average length gained in femoral bone was 4.7 cms (range, 3 to 7 cms). The average duration of total treatment was 10.1 months (range, 7 to 15 months). The healing index was 2.2 (number of months per 1 cm elongation) on average. All patients were satisfied with the results, but all felt that it was an uncomfortable procedure. According to our experience, we conclude that the method of Ilizarov is an useful technique for femoral lengthening. However, it is an uncomfortable and tedious procedure.

A credentialing program for nursing staff caring for pediatric patients with an ilizarov apparatus

The purpose of this article is to provide an overview of an educational program that was implemented at a postacute pediatric rehabilitation facility to prepare the nursing staff to provide quality care for patients undergoing limb lengthening. Patients undergoing limb lengthening and limb reconstruction by the Ilizarov orthopedic method wear a highly complex external fixation device that has numerous variations. As such, it is a type of apparatus that pediatric rehabilitation nurses are unaccustomed to dealing with in the clinical arena. The nursing department at the facility described in this article undertook an intensive educational and credentialing program to ensure staff competency, parent satisfaction, and quality patient care for cases involving limb lengthening and reconstruction.

Reactivation of a mandibular lengthening device for maximal distraction

A technique for reactivating the Howmedica mini-lengthening device is presented. This procedure, performed in the clinic, allows for mandibular distraction in excess of the standard maximum of 25 mm.

Introduction of an intraoral bone-lengthening device

It has been demonstrated that distraction osteogenesis is an effective clinical tool with applications for the entire human skeleton. Therapeutic exploitation in the correction of the asymmetrical and hypoplastic mandible has been reported previously. However, the main criticism of this technique has been the residual cutaneous scars resulting from the surgical incision and the path of the expansion device. In order to obviate the need for skin incisions, we have developed and demonstrated the feasibility of a miniaturized mandibular bone lengthener that is suitable for intraoral placement. Ten growing mongrel dogs were studied. Under general anesthesia, a buccal mucosal incision was made along the oblique line, and the body and ramus of the mandible were exposed in a supraperiosteal plane. Two 2.0-mm half-pins were placed percutaneously in the area of the angle of the mandible, and two other pins were placed 3.5 cm anteriorly. The clamps of the lengthening device were then attached to the half-pins in an intraoral position. An osteotomy was made by connecting percutaneously made drill holes between the clamps in a line positioned posterior to the third molar. The mucosa was closed loosely over the device. Distraction was commenced on the eighth postoperative day. The results were assessed with pre- and post-lengthening photographs, cephalograms, and CT scans with three-dimensional reconstruction. All animals demonstrated a contralateral cross-bite. The newly developed bone also was examined histologically. The intraoral method of mandibular lengthening offers the same advantages of extraoral lengthening but without the need for a cutaneous incision and resulting scar.

Effect of mandibular distraction on the temporomandibular joint: Part 1, Canine study

The effect of osteodistraction on the temporomandibular joint was evaluated in a canine model. Eleven mongrel dogs were used in the study. An intraoral expansion device was placed after an osteotomy was made at the angle of the mandible via an intraoral approach. The mandibles were expanded either fully to 20 mm or partially to 10 mm. After expansion, nine animals were immediately killed; the remaining two were maintained in fixation for an additional 10 weeks. Cephalometric radiographs and computed tomographic scans obtained preoperatively and before killing were evaluated. No gross temporomandibular joint deformation or bodily movement was noted in the expanded or contralateral, unexpanded side. The temporomandibular joints were harvested en bloc for gross and microscopic evaluation. Flattening of the posterior aspect of the expanded condylar head was noted, with thinning of the condylar cartilage. New bone deposition was noted, which was evident as anterior lipping. Condyles maintained in 10 weeks fixation showed reparative changes. No evidence of avascular necrosis, microfracture, or cystic degeneration was noted. This study indicates that the force of distraction can induce bony changes in the temporomandibular joint and that these effects are minimal and reversible.

Effect of mandibular distraction on the temporomandibular joint: Part 2, Clinical study

Mandibular lengthening by gradual distraction has been gaining popularity. However, the effect of osteodistraction on the temporomandibular joint has been evaluated in patients with craniofacial anomalies who underwent mandibular distraction. Five patients had unilateral expansion and five had bilateral expansion. The mandibles were expanded 1 mm per day until the pogonion was in the midline. Preoperative, immediate, 6-month, and 12-month panoramic and cephalometric radiographs were evaluated. In unilaterally expanded mandibles, the ipsilateral condyle increased in size and volume, became more upright, and was oriented in a more normal vertical axis. The contralateral unexpanded condyle did not show deformational changes. In those mandibles that were bilaterally expanded, both condyles increased in size and volume and became more symmetrical and upright. Osteodistraction appears to affect bone in both local and distant sites. The expanded condyles were stimulated to ensure a more nearly normal shape, size, and configuration.

An approach to the management of radial longitudinal deficiency

This paper describes an approach to the management of radial longitudinal deficiency. Early treatment includes manipulation and splintage prior to realignment of the carpus on the forearm. Twelve patients are presented in which a comparison is made between centralisation and radialisation surgical techniques. Preoperative distraction allowed radialisation without excision of a part of the carpus in five out of six patients. In contrast, centralisation with carpal excision was necessary in 5 out of 6 patients not treated by preoperative distraction. It remains to be seen whether radialisation is a superior procedure to centralisation in the longer term. However, radialisation in theory allows greater protection for the distal ulnar physis, maintains maximal length, and allows optimal wrist motion. Late treatment of radial longitudinal deficiency includes techniques of bone lengthening and correction of radial deviation deformity. Three cases are presented in which the Ilizarov technique was used to lengthen the forearm and to correct deformity. The complications of forearm lengthening are high but these techniques do allow significant correction of deformity.

[Open segmental bone transport. A therapeutic alternative in post-traumatic and osteitis soft tissue and bone defects]

Between 1990 und 1992, 22 patients with bone and soft tissue defects were treated by open segmental bone transport according to Ilizarov, and 20 of these were followed up over a period of 18 months after removal of the external fixator. In 19 cases the bone defect could be filled by callus distraction only, while 1 patient needed additional spongeous bone transplantation because of delayed ossification. In 1 case amputation was necessary because of extensive fistula carcinoma of the resected bone and soft tissue. Closure of soft tissue defect was achieved in 14 patients simultaneously with docking of the bone segments. In 5 patients additional skin transplantation was needed, and in 1 case a latissimus dorsi flap had to be transferred because of unstable scar formation. Transporting vital bone simultaneously with the overlying tissue into a defect allows for limb salvage even in poor biological conditions and in patients with vascular problems. Open bone transfer has extended the range of methods available for the treatment of bone and soft tissue defects.

[Possible applications of ultrasound in corticotomy-callus distraction]

Sonographic examination can yield additional information in the course of corticotomy-callus distraction. Hence, we focus on individual slices--which are different from the standardised ultrasound examination of the skeleton system--in the area of the corticotomy-callus distraction. In ultrasound examination the structure of corticalis in the field of corticotomy is scanned circularly. Depending on the point of time of the corticotomy between the structure of corticalis, the callus can be visualised sonographically. The callus distraction can be divided into three stages: I. echo-poor structure between the two ends of the corticalis, II. echo-rich structure between the two ends of the corticalis, III. area of corticalis in the area of distraction with (III a), visualised without (III b) break. The described method is an additional low-cost imaging procedure in diagnosis, for the patient free of radiation and stress, which can yield additional information during and after completed callus distraction (question of permissible emotional stress). The examination is reproducible. The x-ray-controls in the course of time are mandatory, because the sonographic examination cannot judge reliably the deviation of the axis in the area of callus distraction.

Surgically assisted rapid orthodontic lengthening of the maxilla in primates--a pilot study

Orthodontic and surgical treatment of patients with maxillary retrusion and/or midface hypoplasia is challenging. This study was designed to show that the maxilla can be successfully lengthened by surgical assisted rapid orthopedic movement, using the principles of distraction osteogenesis. Three experimental and three control adolescent cynomolgus primates were used in this study. Metallic markers were placed in the cranial base and the maxilla and cephalometric x-ray films were taken. An orthodontic appliance was constructed with a Glen-Ross screw (Dentaurum, Newtown, Pa.) oriented anteroposteriorly. Anterior supraapical osteotomies of the maxilla were carried out. Bilateral horizontal and interdental osteotomies were created between the first premolars and the canine; the anterior six tooth dental-osseo segment was completely mobilized in all animals. Beginning 1 week after surgery, the orthodontic appliance was opened a quarter turn every 2 days until the anterior segment was advanced by 4 mm in two animals and 6 mm in one animal. Animals were killed at 6, 8, and 12 weeks after completion of the maxillary orthopedic advancement. Computerized tomographic scans of the maxillae were completed, and the specimens were then prepared by routine histologic methods for examination by light microscopy. The computerized tomographic scans showed bone deposition in the osteotomy sites, which was confirmed by histologic observations. Since this technique demonstrated repair by bone rather than soft connective tissue in the osteotomy sites, this procedure could be a useful method of treating midface retrusion.

Anterior maxillary advancement using tooth-supported distraction osteogenesis

PURPOSE

This study used the principle of distraction osteogenesis to advance the anterior maxilla of the dog using a totally tooth-supported distraction device.

MATERIALS AND METHODS

After an anterior maxillary osteotomy, the distraction device was activated 0.5 mm every 12 hours to advance the anterior segment 10 mm in 10 days.

RESULTS

Serial tooth and radiographic measurements indicated that on the 10th day the average tooth advancement was 8.4 mm +/- 1.5 mm and the average skeletal advancement was 4.0 mm +/- 1.5 mm. After 6 weeks the average tooth advancement was 7.2 +/- 1.6 mm and the average skeletal advancement was 3 +/- 1.3 mm. At 3 months the tooth advancement was 6.2 +/- 1.5 mm and at 6 months the tooth advancement was 5.0 +/- 1.1 mm. Bone healing was present in all animals.

CONCLUSION

This results of this study indicate that a tooth-borne maxillary distraction device will result in significantly greater dental movement than skeletal movement and that skeletal fixation may be needed for appliances used to advance the maxilla.

Bifocal surgery for deformity and bone loss after lower-limb fractures. Comparison of bone-transport and compression-distraction methods

We report the results in the first 16 patients treated in Sheffield using bifocal techniques for diaphyseal bone loss and deformity secondary to trauma. Eight patients had bone-transport and eight had compression-distraction methods. At a mean follow-up of 24 months all 16 had excellent or good results with union of the fracture, correction of deformity and normal or near normal leg length. There were no major complications. Mean treatment times were 16 months for bone transport and 9.8 months for compression-distraction. Bone transport was more complicated requiring an average of 2.2 additional operations compared with only one for compression-distraction. Femoral cases had shorter treatment indices than tibial cases but had less favourable outcomes.

Midface advancement in sheep by gradual distraction: a 1-year follow-up study

PURPOSE

The purpose of this study was to find a solution to the unsatisfactory postoperative maxillary relapse after major maxillary advancement or inferior repositioning of the maxilla.

MATERIALS AND METHODS

Major midface advancement by gradual distraction was performed on three young adult sheep over 21 days. Using an external device, the midface was advanced 36 mm in the nasofrontal area and 43 mm in the lateral aspect of the maxilla. The apparatus remained as an external fixation device for 6 weeks after the distraction to allow better ossification. After removal of the device, a 1-year clinical and radiographic follow-up was conducted.

RESULTS

Direct measurements between the markers showed 2- to 3-mm relapse after 1 year. Radiologic measurements demonstrated that the relapse occurred during the first 3 months after removal of the distraction apparatus.

CONCLUSION

It was concluded that midface advancement by gradual distraction may obviate the need for bone grafting and offer a greater movement of bone segments with good skeletal stability.