Aims. Many authors have reported a shorter treatment time when using trifocal bone transport (TFT) rather than bifocal bone transport (BFT) in the management of long segmental tibial bone defects. However, the difference in the incidence of additional procedures, the true complications, and the final results have not been investigated. Patients and Methods. A total of 86 consecutive patients with a long tibial bone defect (≥ 8 cm), who were treated between January 2008 and January 2015, were retrospectively reviewed. A total of 45 were treated by BFT and 41 by TFT. The median age of the 45 patients in the BFT group was 43 years (interquartile range (IQR) 23 to 54). Results. The size of the bone defect was significantly longer (p = 0.005), the number of previous operations was significantly higher (p < 0.001), the operating time was significantly longer (p < 0.001), and the bone transport distance was significantly increased (p = 0.017) in the TFT group. However, the external fixation time (p < 0.001), the healing index (p < 0.001), the number of additional procedures (p = 0.013), and the number of true complications (p < 0.001) were significantly reduced in this group. Both groups achieved highly satisfactory bone and functional results. Conclusion. TFT can significantly reduce the treatment time, the number of additional surgical procedures, and true complications compared with BFT in the treatment of long segmental tibial bone defects

Although gradual bone transport may permit the restoration of large-diameter bones, complications are common owing to the long duration of external fixation. In order to reduce such complications, a new technique of bone transport involving the use of an external fixator and a locking plate was devised for segmental tibial bone defects. A total of ten patients (nine men, one woman) with a mean age at operation of 40.4 years (16 to 64) underwent distraction osteogenesis with a locking plate to treat previously infected post-traumatic segmental tibial defects. The locking plate was fixed percutaneously to bridge proximal and distal segments, and was followed by external fixation. After docking, percutaneous screws were fixed at the transported segment through plate holes. At the same time, bone grafting was performed at the docking site with the external fixator removed. The mean defect size was 5.9 cm (3.8 to 9.3) and mean external fixation index was 13.4 days/cm (11.8 to 19.5). In all cases, primary union of the docking site and distraction callus was achieved, with an excellent bony result. There was no recurrence of deep infection or osteomyelitis, and with the exception of one patient with a pre-existing peroneal nerve injury, all achieved an excellent or good functional result. With short external fixation times and low complication rates, bone transport with a locking plate could be recommended for patients with segmental tibial defects. Cite this article: Bone Joint J 2013;95-B:1667–72

Introduction. Bone transport and distraction osteogenesis have been shown to be an effective treatment for significant bone loss in the tibia. However, traditional methods of transport are often associated with high patient morbidity due to the pain and scarring caused by the external frame components transporting the bone segment. Prolonged time in frame is also common as large sections of regenerate need significant time to consolidate before the external fixator can be removed. Cable transport has had a resurgence with the description of the balanced cable transport system. However, this introduced increasingly complex surgery along with the risk of cable weave fracture. This method also requires frame removal and intramedullary nailing, with a modified nail, to be performed in a single sitting, which raised concern regarding potential deep infection. An alternative to this method is our modified cable transport system with early intramedullary nail fixation. Internal cables reduce pain and scarring of the skin during transport and allow for well controlled transport segment alignment. The cable system is facilitated through an endosteal plate that reduces complications and removes the need for a single-stage frame removal and nailing procedure. Instead, the patients can undergo a pin-site holiday before nailing is performed using a standard tibial nail. Early intramedullary nailing once transport is complete reduces overall time in frame and allows full weight bearing as the regenerate consolidates. We present our case series of patients treated with this modified cable transport technique. Methodolgy. Patients were identified through our limb reconstruction database and clinic notes, operative records and radiographs were reviewed. Since 2019, 8 patients (5 male : 3 female) have undergone bone transport via our modified balanced cable transport technique. Average age at time of transport was 39.6 years (range 21–58 years) with all surgeries performed by the senior author. Patients were followed up until radiological union. We recorded the length of bone transport achieved as well as any problems, obstacles or complications encountered during treatment. We evaluated outcomes of full weight bearing and return to function as well as radiological union. Results. 4/8 bone defects were due to severely comminuted open fractures requiring extensive debridement. All other cases had previously undergone fixation of tibial fractures which had failed due to infection, soft tissue defects or mal-reduction. The mean tibial defect treated with bone transport was 41mm (range 37–78mm). From the start of cable transport to removal of external fixator our patients spent an average of 201 days in frame. 7/8 patients underwent a 2-week pin-site holiday and subsequent insertion of intramedullary nail 2 weeks later. One patient had sufficient bony union to not require further internal fixation after frame removal. 10 problems were identified during treatment. These included 4 superficial infections treated with antibiotics alone and 5 issues with hardware, which could be resolved in the outpatient clinic. 1 patient had their rate of transport slowed due to poor skin quality over the site of the regenerate. 4 obstacles resulted in a return to theatre for additional procedures. 1 patient had a re-do corticotomy and 3 had revision of their internal cable transport constructs due to decoupling or screw pull out. 1 patient had residual ankle joint equinus following treatment which required an Achilles tendon lengthening procedure. Another patient underwent treatment for DVT. There were no deep infections identified and no significant limb length discrepancies or deformities. Conclusions. Overall, we have found that our modified balanced cable transport technique has allowed for successful bone transport for significant defects of the tibia. We have learned from the obstacles encountered during this case series to avoid unnecessary return trips to theatre for our future transport patients. The internal cable system allowed all patients to complete their planned transport without excessive pin tract scarring or pain. Early conversion to intramedullary nail allowed for a shorter time in frame with continued full weight bearing as the regenerate consolidated. No metalwork failure or deformity has occurred in relation to docking site union. All patients have made a good return to pre-operative function during their follow-up period with no evidence of late complications such as deep infection

The segmental bone transport allows the reconstruction of large scale bone defects resulting after a redical debridement due to an infection or after trauma. We use the Ilizarov fixator for the segmental transport. The part of the bone that has to be moved through the defect is pulled by a lateral and a medial towing rope. To determine continuously the forces of tension in the wires and to detect early complications of the bone transport we implanted in each wire a load cell with a resistance strain gauge. The knowledge of the resulting forces leads to the development of an automatic forced controlled bone transport. Since 09/2004 we have measured the forces of tension in the wires in 77 patients undergoing a segmental bone transport due to a long-extending osteomyelitis. The average age was 47,2 (6 to 68). In 12 patients we had to treat a bone defect of the thigh (average size of the defect 12,5 cm), in 55 patients 56 large scale bone defects of the lower leg (average size of the defect: 8,6 cm ranging from 6,0 to 20,0 cm). We implanted a load cell with a resistance strain gauge in the lateral and medial towing rope. This way we could, after converting the measured values from analog to digital, the impacting forces. In all patients we were able to meausure continuously rising forces of tension. Lwe noticed forces which didn´t change much. At the end the bone transport we again found rising forces of tension. We noticed higher forces in the lateral wires, on femur and on tibia. Due to the measurement of the acting forces we were abel to perform a bone transport without close X-ray-monitoring. Complications such as premature ossification of the new building bone were identified and treated in an early stage.at. We developed a theoretical model drawing into consideration the interfering forces caused by the regenerating bone, the soft tissue, the friction of the wire, adherend soft tissue and geometry otf the wire. The forces calculated using this model were similar to the acting forces we found when measuring the forces of the bone transport. We now record the data on memory cards. A control of the data is possible over long-distance. We now started a model of an automatic bone transport controlled by the the acting forces. Our aim is to perform such an automatic bone transport in patients

Aim. Untreated or improperly managed osteomyelitis can lead to several complications, bone loss being one of the most challenging to manage. Bone transport is just one of the surgical options available for filling the bone gaps and promote bone union. This presentation focuses on bone transport for long bones gaps in paediatric age group, highlighting its advantages and disadvantages, its indications and its complications. Method. Between 2006 and 2014. 71 patients underwent a procedure of bone transport. Out of them, 39 were males and 32 females, with an average age at presentation of 8.7 years. The bone involved were tibia (27 right, 25 left), femur (4 right, 9 left), radius (1 right, 4 left) and ulna (1 right). Clinically speaking, the children presented with one of the following picture:. ‐. Pathological fracture, with sequestration without or minimum involucrum formation. ‐. Extensive, extruded diaphyseal sequestrum, with loss of soft tissues. ‐. Post-surgical gap, with residual or quiescent infection. Bone transport was preceded by one of the following procedure: sequestrectomy, sequestrectomy and external fixation, external fixation with sequestrum in situ. Monolateral fixator was used in 46 patients, ring fixator in 25. Bone transport started 7 days after the osteotomy, at the rhythm of 1 mm per day. Plastic surgery procedures were used in 3 kids. Results. Bone reconstruction was primarily obtained in 50 patients; non-union at the docking point was observed in 18. It required additional procedures of bone graft or site refreshening, associated with external fixation. Pins replacements and/or fixator adjustment were required in 24 patients. Several procedures were required during transport to overcome technical mistakes or to handle unexpected complications. All patients were able to walk unsupported. Reduced knee flexion was observed in 11 patients, knee fusion in 4, ankle fusion in 3, limb length discrepancy in 20, axial deformity in 6. Conclusions. Bone transport has proved to be a reliable technique for managing segmental bone defects in children. It requires long time and it is prone to several complications. Strict medical supervision is necessary all along the process. Besides filling the gap, it can achieve limb equalization when needed. The presence of infection is not a contraindication to concurrent sequestrectomy and transport. The treatment is long, challenging, strenuous for the patient, the family and the medical staff but the results can be rewarding in terms of limb function

Introduction. We demonstrate the preliminary results with a novel technique to solve large bone defects using two lengthening nails, working together and aligned in a custom made device. An illustrative case that successfully produced 17 cm bone in 3.5 months, is presented. Materials and Methods. A 28 year old healthy male presented with a slowly growing mass in the left femur. No general symptoms were reported, no weight loss, no previous illness. Histopathology, CT and MRI scans revealed a malignant diaphyseal bone tumor. A three-stage trifocal bone transport was projected and conducted based on a 3D model test. Results. Trifocal bone transport using two lengthening nails in a custom made device, reduced the 17 cm bone defect in 3.5 months. Follow up was 9 months. Conclusions. The presented technique successfully solved the clinical problem and is a showcase for further developments of internal devices for complex and large bone losses and lengthenings

The feasibility of bone transport with bone substitute and the factors which are essential for a successful bone transport are unknown. We studied six groups of 12 Japanese white rabbits. Groups A to D received cylindrical autologous bone segments and groups E and F hydroxyapatite prostheses. The periosteum was preserved in group A so that its segments had a blood supply, cells, proteins and scaffold. Group B had no blood supply. Group C had proteins and scaffold and group D had only scaffold. Group E received hydroxyapatite loaded with recombinant human bone morphogenetic protein-2 and group F had hydroxyapatite alone. Distraction osteogenesis occurred in groups A to C and E which had osteo-conductive transport segments loaded with osteo-inductive proteins. We conclude that scaffold and proteins are essential for successful bone transport, and that bone substitute can be used to regenerate bone

Segmental bone transport (SBT) with an external fixator has become a standard method for treatment of large bone defect. However, a long time-application of devices can be very troublesome and complications such as nonunion is sometimes seen at docking site. Although there have been several studies on SBT with large animal models, they were unsuitable for conducting drug application to improve SBT. The purpose of this study was to establish a bone transport model in mice. Six-month-old C57BL/6J mice were divided randomly into bone transport group (group BT) and an immobile control group (group EF). In each group, a 2-mm bone defect was created in the right femur. Group BT was reconstructed by SBT with external fixator (MouseExFix segment transport, RISystem, Switzerland) and group EF was fixed simply with unilateral external fixator (MouseExFix simple). In group BT, a bone segment was transported by 0.2 mm per day. Radiological and histological studies were conducted at 3 and 8 weeks after the surgery. In group BT, radiological data showed regenerative new bone consolidation at 8 weeks after the surgery, whereas high rate of nonunion was observed at the docking site. Histological data showed intramembranous and endochondral ossification. Group EF showed no bone union. In this study, experimental group showed good regenerative new bone formation and was similar ossification pattern to previous large animal models. Thus, the utilization of this bone defect mice model allows to design future studies with standardized mechanical conditions for analyzing mechanisms of bone regeneration induced by SBT

Introduction: Bone transport, or distraction osteogenesis, is a recognised technique to reconstruct extensive bony defects resulting from excision of bony tumours. Ilizarov demonstrated bone formation under tension allowing the movement of a free segment of living bone to fill intercalary defects. This study assesses the use of bone transport in the management of patients with resectable long bone tumours. Methods: We retrospectively reviewed patients who underwent bone transport in two institutions, performed by a single surgeon. A total of 14 patients were included in the study. There were 11 males and 3 females. Histological results demonstrated osteosarcoma (n=7), Ewing’s sarcoma (n=6), and parosteal chondrosarcoma (n=1). The site of the tumour was the femur and tibia in 8 and 6 cases respectively. Results: Bone transport was fully completed in 9 patients. Of the 5 patients remaining, 3 are currently in cast, 1 is currently undergoing tibial lengthening, and 1 patient died from local recurrence and distant spread of disease. The average length of bone resected in the tibia was 11 cm (range 8–15 cm), while in the femur the average was higher at 16.5 cm (range 12–27 cm). All patients underwent autologous bone grafting of their docking site from either the anterior or posterior iliac crest on the ipsilateral side. The average time in frame was 24.8 months. One patient undergoing tibial bone transport fell and sustained an ipsilateral supracondylar femoral fracture which was successfully treated with an external ring fixator. Discussion: Bone transport is a recognised method of reconstructing extensive bony defects and is beneficial for patients with a good prognosis. It is a specialised technique and requires a multidisciplinary approach. Other techniques can be less time consuming however distraction osteogenesis avoids the complications associated with prosthetic or allograft replacements

The December 2023 Trauma Roundup. 360. looks at: Distal femoral arthroplasty: medical risks under the spotlight; Quads repair: tunnels or anchors?; Complex trade-offs in treating severe tibial fractures: limb salvage versus primary amputation; Middle-sized posterior malleolus fractures – to fix?; Bone transport through induced membrane: a randomized controlled trial; Displaced geriatric femoral neck fractures; Risk factors for reoperation to promote union in 1,111 distal femur fractures; New versus old – reliability of the OTA/AO classification for trochanteric hip fractures; Risk factors for fracture-related infection after ankle fracture surgery

Aim. To evaluate the results and complications of bone transport in the treatment of massive tibial bone defects, using the Ilizarov method. Methods. 15 patients underwent bone transport using the Ilizarov technique to treat massive tibial bone defects. The average age of the patients was 8.7 years (3–24 years) and the mean bone defect was 10.8 cms. Following a latent period of 1 week, distraction of the transport doughnut was commenced at 1mm/24 hours in 4 quarterly turns. A docking procedure was performed in 7 cases which involved freshening of the bone ends and autogenous bone grafting from the iliac crest. Following docking the fixator was removed once the regenerate had consolidated. Results. The fixators were removed after a mean 12.3 months (range 8–21 months). 1 patient required adjustment of the frame under anaesthetic due to translation of the docking doughnut and poor alignment. All patients had at least one superficial pin site infection successfully treated with oral antibiotics. Deep infection at the docking site was seen in 1 patient needing debridement and split skin grafting. There were no neuro-vascular complications. 1 patient had a recurvatum deformity at the regenerate due to early frame removal. There were no early fractures. Re-fracture of the docking site occurred in one patient, 17 months after the removal of the original frame. This needed open reduction and internal fixation. Non union at the docking site was seen in 3 patients, needing open reduction, internal fixation with bone grafting (1 case) and excision of non-union and compression with a further frame (2 cases). Conclusion. Massive bone transport in the tibia is an orthopaedic challenge. This paper highlights the complications of this procedure. It confirms the viability of this method but emphasises careful counselling of both the patient and parents prior to the commencement of such difficult treatment

Bone transport/limb lengthening with circular external fixation has been associated with a prolonged period of time in the frame and a significant major complication rate following frame removal. We examined the results of bone transport in fifty-one limbs using the “monorail” technique and found a dramatically improved lengthening index (24.5 days/cm. – time in frame /cm. of length gained) and an absence of refracture or angulatory deformity following fixator removal. This technique is our treatment of choice for limb lengthening/bone transport. We sought to determine patient oriented outcome and complication rates following b one transport using an external fixator placed over an intramedullary nail (the “monorail” technique). Bone transport using the monorail technique is associated with a dramatically improved lengthening index and a lower major complication rate than traditional ring fixator methods. Patient satisfaction with the procedure was high. Our study confirms the significant advantages of the monorail technique for bone transport/limb lengthening. The time in the fixator is dramatically reduced, and complications associated with earlier techniques such as angulatory deformity or refracture were not seen. We identified forty-nine patients (fifty-one limbs) who had undergone bone transport using the monorail technique (external fixator placed over an intramedullary nail). There were thirty-five men and fourteen women with a mean age of thirty-five years (range 17–50). Pre-operative diagnoses included post traumatic length discrepancy/bone defect (forty-one), congenital short stature (six) and other (four). All patients had a unilateral fixator placed over an implanted intramedullary nail. Once length correction was achieved, the fixator was removed and the nail “locked”. The mean amount of lengthening was 5.5 cm. (range 2 – 18 cm.). The lengthening index was 24.5 days /cm. (duration of external fixation/cm. bone length gained), with a range from ten to fifty days /cm. There were nineteen complications (thirty-seven percent): nine premature consolidations, four infected pin sites, two hardware failures, two osteomyelitis, one DVT, one nonunion. There were no refractures, angulatory deformities or cases of intramedullary sepsis

Aim. Infected segmental defects are one of the most feared complications of open tibial fractures. This may be due to prolonged treatment time, permanent functional deficits and high reinfection and non-union rates. Distraction osteogenesis techniques such as Ilizarov acute shortening with bifocal relengthening (ASR) and bone transport (BT) are effective surgical treatment options in the tibia. The aim of this study was to compare ASL with bone transport in a consecutive series of complex tibial infected non-unions and osteomyelitis, for the reconstruction of segmental defects created at surgical resection of the infection. Method. In this single centre series, all patients with a segmental defect (>2cm) of the tibia after excision of infected non-union or osteomyelitis were eligible for inclusion. Based on clinical features, bone reconstruction was achieved with either ASR or BT using an Ilizarov fixator. We recorded the external fixation time (months), the external fixation index (EFI), comorbidities, Cierny-Mader or Weber-Cech classification, follow-up duration, time to union, number of operations and complications. Results. Overall, 43 patients with an infected tibial segmental defect were included. An ASR was performed in 19 patients with a median age of 40 years (range: 19 – 66 years). In this group, the median bone defect size was three cm (range: 2 – 5 cm); and the median frame time eight months (range: 5 – 16 months). BT was performed in 24 patients with a median age of 44 years (range: 21 – 70 years). The median bone defect size was six cm (range: 3 – 10 cm), and the median frame time ten months (range: 7 – 17 months). The EFI in the ASR group and the BT group measured 2.2 months/cm (range: 1.3 – 5.4 months/cm) and 1.9 months/cm (range: 0.8 – 2.8 months/cm), respectively. The comparison between the EFI of the ASL group and the BT group showed no statistically significant difference (p=0.147). Five patients of the ASR group (7 surgeries) and 19 patients of the BT group (23 surgeries) needed further unplanned surgery (p=0.001). Docking site surgery was significantly more frequent in BT; 66.7%, versus ASL; 5.3% (p=0.0001). Conclusion. Acute shortening/relengthening and bone transport are both safe and effective distraction osteogenesis techniques for the treatment of infected tibial non-unions. They share similar frame times per centimetre of defect. However, ASR demonstrated a statistically significant lower rate of unplanned surgeries

Introduction: Infected non-union in the forearm is a rare and challenging situation. It can result in persistent deformity, shortening, bone loss, joint stiffness and disability. Secondary procedures are often required for correction of bone defects and deformity. Bone transport may be the only realistic method of treatment. Case presentation: 56-year-old gentleman referred with an infected non-union of left distal radius. He underwent bone debridement with ilizarov frame application for distraction osteogenesis. After a period of one month, a longitudinal transport wire was inserted through the distal segment to the proximal segment and distraction was carried using this wire. This was supplemented by iliac crest bone graft and OP-1 substitute at docking stage. The frame was removed at 18 months, following which he sustained a refracture. ORIF with bone graft was performed. Finally a good consolidation was achieved. There was about 50% loss in pronation and supination and about 15 degrees short of full extension at the final followup. Another 57-year-old gentleman referred for an infected non-union of the ulna with a severe bone defect. He was treated with a TSF application and corticotomy for distraction osteosynthesis. There has been a satisfactory progress in the bone transport and recently underwent a docking procedure with bone graft insertion. Discussion: Post traumatic infected non-union with segmental bone defect in the forearm can be successfully managed with bone transport. Unlike tibia, where this procedure is commonly done, forearm bones have a complex soft tissue envelope which can rule out the use of external transport, especially in the radius. We found the longitudinal wire technique useful for transport of radius. Internal fixation can be used to salvage initial failures, provided that infection and substantial bone defects have been eliminated. This treatment is intensive and difficult for patient and surgeon

Different methods of filling bone defects are reported: shortening followed by lengthening or bone transplant. In both cases the resection and docking bone site (immediately or after transplant) has a high risk of delayed consolidation or non-union. The aim of this study was to evaluate the strategies to avoid this risk. We studied 19 patients treated from 1997 to 2002: 11 (group 1) were treated with immediate shortening and proximal callotasis. In eight patients (group 2) we performed monofocal proximal-distal bone transplant. In seven patients of group 1 we performed only decortication of the docking site (group 1A); in four cases (group 1B) decortication was associated with an autologous bone graft. The docking site was checked radiologically and considered healed when we allowed full weight-bearing after fixator removal. In two patients (28.5%) in group 1A, three (75%) in group 1B and two (25%) in group 2 healing was achieved without any other operations. Docking site refracture or pseudoarthrosis was treated in all patients by new decortication and autologous bone graft with an average healing time of 90 days. We suggest performing acute bone loss shortening in combination with decortication and autologous bone graft when local conditions permit. After bone transplant it is not necessary to wait for spontaneous consolidation, but better to plan from the beginning another operation before the two the docking site fragments are in contact. Now we are using AGF and BMP-7 (OP-1) for treatment of the docking site but the study is still underway

Abstract. Distraction Osteogenesis (DO) for the management of bone defects in long bones is an established technique. Problems with bone regeneration are a common occurrence and literature is full of different modalities to enhance regenerate formation and quality. Strontium Ranelate (SR) has a dual mode of action and enhances bone formation in addition to decreasing osteoclastic activity. Due to this dual mode of action as well as ease of administration in a suspension form, it makes an ideal drug in scenarios where realignment of bone homeostasis towards positive bone balance is desirable. We studied the relationship of administration of SR with rate of regenerate progression, docking site union and complications associated with bone transport in 48 patients undergoing bone transport for management of bone defects. The findings of our retrospective observation study indicated that compliant use of SR was associated with good regenerate progression, decreased problems with docking site union and decreased the need for additional interventions

Background. Although gradual bone transport may provide a large-diameter bone, complications are common with the long duration of external fixation. To reduce such complications, a new technique of bone transport with a locking plate has been done for tibial bone defect. Methods. In 13 patients (mean age, 38.9 years) of chronic osteomyelitis or traumatic bone defect, segmental transport was done using external fixator with a locking plate. In surgical technique, a locking plate was fixed submuscularly, holding the proximal and distal segments. Then, the external fixator for transport was fixed without contact of the locking plate. After docking, 2 or 3 screws were fixed at the transported segment through the plate holes. At the same time, the external fixator was removed. Results. The mean transported amount was 5.8cm, and the mean external fixation index was 13.3 days/cm. The primary union at the docking site was achieved in all cases. No patients showed angular deformity over 5 degrees. There were 2 patients of leg length discrepancy with less than 1.5cm. Deep infection or recurrence of osteomyelitis was not developed. Except for two patients with pre-existed peroneal nerve injury, all had excellent or good functions according to the criteria of Mekhail. Conclusion. In tibial reconstruction, transport with a locking plate may be a successful method with reducing external fixation time. It may allow patients to return to daily life earlier with relatively few complications

Aims: We wanted to study the outcome of bone transport by Ilizarovñs method in simple and complicated gap non-unions where other conventional methods have little role to play. Methods: Sixty-six consecutive patients with an age range of 23–64 years (58 males and 8 females) were included in this study. Forty-four patients (67%) had associated problems like infection, deformity and shortening along with gap non unions of varying length. All the patients were treated with ring þxators and the principles of Ilizarovñs treatment were adopted. Corticotomy was carried out in all the cases. Appropriate arrangement of apparatus assembly was done according to the requirement of individual gap non-unions. Follow up ranged from 6 to 46 months. Results: In all but three cases, union was achieved along with satisfactory correction of other associated problems. In one case the patient had previously undiagnosed hypothyroidism and showed signs of callus at corticotomy site after treatment with thyroxine. This patient lost to follow-up. Two other cases needed further surgery (Ilizarovñs ring þxator). In one case, cancellous bone grafting had to be carried out. In six tibial gap non-unions, residual equinus deformity persisted. Conclusions: Ilizarovñs method of bone transport is quite effective in treatment of gap non-unions associated with complex problems, where other methods have proven to be less successful

Introduction The purpose of this study was to compare the time to union following acute shortening and subsequent lengthening versus Bone Transport using the Ilizarov external fixator. Methods Eighteen patients with tibial non-unions (age range 26 to 63 years) were recruited between March 1995 and September 2001. Three subgroups of six patients each, were formed. Group 1 underwent Acute Shortening and subsequent Lengthening, whereas Group 2 underwent Bone Transport. Group 3 patients had defects < 1 cms but were still high energy injuries, therefore underwent application of a frame. This group was used as a comparison group. A proximal corticotomy was used for distraction osteogenesis. Bone grafting at the fracture or regenerate site was used if required to aid healing. All patients were followed-up to union. All three groups were similar for age, pre-injury health status including cigarette smoking. Ten infected non-unions were present. Most patients had at least two conventional operative interventions prior to referral to us for Ilizarov surgery. The mean bone resection in the Acute Shortening group (Group 1) was 4.6 cms and in the Bone Transport group (Group 2) was 5.9 cms. Patients in Group 2 had more procedures done before union was achieved. This included adjustment of frame/ reinsertion of wires to align transport segment for optimal docking and bone grafting at the docking/regenerate site. Four patients in Group 2 required bone grafting at the docking site compared to none in Group 1. Results Eradication of infection and union was achieved in all patients with average time in frame being 12.1 months in the Acute Shortening group, 17.2 months in the Bone Transport group and 8.0 months in the Frame stabilisation group. Using Paley’s bone result evaluation system, an excellent result was achieved in all patients of all groups. However, patients in the Acute Shortening group had a shorter time to union and needed fewer procedures. Conclusions We recommended that where feasible, acute shortening and lengthening is preferable to bone transport due to shorter union time and fewer procedures undertaken to achieve union. If this is not possible due to large defects, then a combination of acute shortening with transport to bridge the gap should be considered

The technique of bone transport with a conventional Ilizarov external fixator is the current standard means of dealing with segmental bone defects not amenable to bone grafting. Problems with control of the distraction of regenerate bone frequently compromises treatment resulting in secondary deformity. Accurate docking of the defect bone ends is also complex to manage with the Ilizarov apparatus, corrections being possible in only one plane at a time (serial processing). The Taylor Spatial external fixator (TSF), (Smith and Nephew, Memphis, Tennessee), is a modified Ilizarov fixator with six telescopic struts that are free to rotate at their connection points to the proximal and distal rings. This combination forms a Stewart Gough platform similar to that used in aircraft simulators. By adjusting only strut lengths, and applying Chasles theorem, one ring can be repositioned with respect to the other. Therefore with the aid of computer software, six axis deformities can be corrected simultaneously (parallel processing). We have used this device over the past 2 years in patients with segmental bone defects of the tibia in a stacked mode of application – a three ring construct with six struts between each pair of rings – to allow simultaneous accurately controlled distraction osteogenesis in one segment and independently controlled closure and compression at the docking site. We present the results of 19 stacked Taylor Spatial frames in 19 patients treated with bone transport in the tibia. The diagnosis was bone resection for infected non union in fourteen, tumour resection in three and acute non infected bone loss secondary to trauma in two. The average age was 34.9 years, (range 10 to 69). Transport ranged from 4 to 12 cm. We used a distraction rate of 0.75mm/day and a comparable compression rate for closure of the defect. At the distraction site, angulation was controlled to within 1degree in any plane and translation to within 1mm in any direction, including length, allowing perfect alignment of the regenerate in all 19 cases. Regenerate quality was uniformly excellent. Superior control of the docking site compared with the Ilizarov fixator was consistently possible and the union rate was 100%. We observed no major complications of treatment. Minor complications included pin and wire infection and breakage all of which were treatable by simple measures with no long term sequelae. In summary our experience with the stacked TSF for bone transport has shown it to be a highly reliable tool. We have achieved perfect control of regenerate bone in all axes and improved clinical outcomes for these complex problems