Knee arthrodesis with simultaneous lengthening using the Ilizarov method

OBJECTIVE: To determine whether knee arthrodesis with simultaneous lengthening using the Ilizarov method for a nonreconstructable knee joint with bone loss and infection is a successful salvage procedure. DESIGN: Retrospective review of patients. SETTING: University hospital-based orthopaedic practice. PATIENTS: From 1999 to 2001, 4 consecutive patients with a nonreconstructable knee joint, bone loss, and infection after trauma underwent knee arthrodesis with simultaneous lengthening. INTERVENTION: Arthrodesis of the knee with simultaneous limb lengthening through an osteotomy of the tibia and/or femur and the use of an Ilizarov frame. External bone stimulation was used at the knee arthrodesis site and the lengthening sites. Application of this device began during the early distraction phase and continued until frame removal. MAIN OUTCOME MEASURES: Bony union at the arthrodesis and bone lengthening sites, alignment of the lower extremity, limb length discrepancy, infection, pain, and outcome scales (SF-36 scores and American Academy of Orthopaedic Surgeons lower limb modules). RESULTS: Bony union of the knee arthrodesis and lengthening sites and good alignment were achieved in all 4 patients. Mean amount of lengthening was 5.4 cm (range 2.5-11.5 cm). Average time in frame was 11 months (range 6-17 months). Limb length discrepancy after treatment averaged 1.8 cm (range 0.6-3.7 cm). Mean duration of follow-up after frame removal was 35 months (range 28-48 months). At follow-up, infection had not recurred, pain was not present, and assistive devices were not needed for ambulation. Average SF-36 scores improved in all 8 categories, and the average American Academy of Orthopaedic Surgeons lower limb modules improved from a mean of 33 (range 11-37) to a mean of 68 (range 51-76). CONCLUSION: Knee arthrodesis with simultaneous lengthening can be performed successfully using the Ilizarov method. It enables surgeons to optimize limb length during knee arthrodesis. The use of external fixation and the avoidance of internal implants may be advantageous in the presence of or history of infection. The Ilizarov frame provides stability that allows weight bearing during treatment.     

Ilizarov's distraction osteogenesis using the mono-fixator system and initial clinical experiences with the injured lower leg

Distraction osteogenesis, as developed by Ilizarov, allows the limbs to be lengthened and intercalary defects to be filled by bone transport without the use of bone grafts. In five patients with traumatic sequelae (fractures of the lower leg), unilateral dynamic mono_fixation and a special distraction apparatus were used for application of the Ilizarov technique. With the distraction device, gradual distraction of the osteotomy surfaces (1/3 mm in three steps per day) is easy for the patients to perform. In three cases distraction osteogenesis was used to correct shortening of the lower leg and in two cases for bridging a tibial defect due to an infection in the plate osteosynthesis. In all cases, the course of treatment and bone healing were uneventful. Based on our first clinical experiences, we believe that mono_fixation provides appropriate stability and the distraction apparatus permits appropriate bone transportation for successful distraction osteogenesis in the tibia.     

Distraction osteogenesis for nonunion after high tibial osteotomy.

The purpose of this study was to determine whether distraction osteogenesis can be used to treat hypertrophic nonunion associated with angular deformity and shortening after Coventry style high tibial osteotomy. Five consecutive patients were retrospectively reviewed. In all patients the alignment had collapsed into excessive varus or valgus and leg length discrepancy was present. The leg length discrepancy, malalignment, and nonunion were treated simultaneously with distraction. Union was achieved by the time of fixator removal, which averaged 4.4 months. The Hospital for Special Surgery knee score significantly improved from 42 to 89. The mechanical axis deviation significantly improved by 5 cm. The coronal plane deformity significantly improved by 13 degrees, and leg length discrepancy improved significantly from 2.3 to 0.5 cm. Metaphyseal bone stock increased by 43%, and the Insall-Salvati ratio increased from 1.1 to 1.2 and remained within normal limits. All patients were satisfied with the procedure, and none have had or need a total knee replacement at an average followup of 4 years. Distraction osteogenesis of nonunion after high tibial osteotomy is a minimally invasive and successful procedure. It leads to bony union with correction of deformity and leg length discrepancy and prevents the need for total knee replacement at intermediate-term followup. The increase in metaphyseal bone stock may make total knee replacement technically easier.     

Reconstruction of juxta-articular huge defects of distal femur with vascularized fibular bone graft and Ilizarov's distraction osteogenesis

BACKGROUND: We evaluate the effect of reconstructing huge defects (mean, 15.8 cm) of the distal femur with Ilizarov's distraction osteogenesis and free twin-barreled vascularized fibular bone graft (TVFG). METHODS: We retrospectively reviewed a consecutive series of five patients who had cases of distal femoral fractures with huge defects and infection that were treated by the Ilizarov's distraction osteogenesis. After radical debridement, two of the five cases had free TVFG and monolocal distraction osteogenesis, and another two cases had multilocal distraction osteogenesis with knee fusion because of loss of the joint congruity. The other case with floating knee injury had bilocal distraction osteogenesis and a preserved knee joint. The mean defect of distal femur was 15.8 cm (range, 14-18 cm) in length. RESULTS: The mean length of distraction osteogenesis by Ilizarov's apparatus was 8.2 cm. The mean length of TVFG was 8 cm. The average duration from application of Ilizarov's apparatus to achievement of bony union was 10.2 months (range, 8-13 months). At the end of the follow-up, ranges of motion of three knees were 0 to 45 degrees, 0 to 60 degrees, and 0 to 90 degrees. Two cases had knee arthrodesis with bony fusion because of loss of the joint congruity. There were no leg length discrepancies in all five patients. In addition, three patients had pin tract infections and one case had a 10 degree varus deformity of the femur. CONCLUSIONS: Juxta-articular huge defect (>10 cm) of distal femur remains a challenge to orthopedic surgeons. Ilizarov's technique provides the capability to maintain stability, eradicate infection, restore leg length, and to perform adjuvant reconstructive procedure easily. In this study, we found that combining Ilizarov's distraction osteogenesis with TVFG results in improved patient outcome for patients with injuries such as supracondylar or intercondylar infected fractures or nonunion of distal femur with huge bone defect.     

膝关节牵伸技术治疗先天性多发性关节挛缩症屈膝畸形

目的　探讨用膝关节牵伸技术 (Ilizarov)治疗先天性多发性关节挛缩症屈膝畸形的方法及疗效。方法　 1998年 8月至 2 0 0 3年 2月收治先天性多发性关节挛缩症 6例 ,其中双膝 4例 ,共 10个膝关节。男 5例 ,女 1例 ,年龄 3岁 7个月至 13岁 ,平均年龄 8岁 2个月。术前屈膝畸形程度平均5 1° ,合并肢体其它部位畸形 13个。应用改良Ilizarov膝关节牵伸器 ,手术安装牵伸器时 ,应维持膝关节于最大伸展位 ,牵伸器的关节铰链对准膝关节的旋转中心 ,于膝上下股骨和胫骨各穿 2组 2mm克氏针与牵伸器上下的钢环固定。术后 5d旋转延长膝后的螺纹牵伸杆 ,第 1周 2～ 3mm/d ,第 2周后改成 1～ 2mm/d ,直至达到膝关节伸直到 0°位。合并髋、足关节畸形者 ,同期或第二期实施手术矫正。本组术后膝关节牵伸时间 2 3～ 4 8d ,平均 37d ,治疗期间患肢可负重锻炼 ,停止牵伸 2周后拆牵伸器再装支具行走。结果　 10个膝关节屈曲畸形完全矫正 ,无严重并发症 ,其中 9个膝术后随访平均 1年 3个月 ,畸形无复发 ,患者行走功能显著改善。结论　Ilizarov技术治疗先天性多发性关节挛缩症屈膝畸形 ,方法简单、安全 ,效果确实 ,符合生物学原理和微创外科的原则     

Osteofibrous dysplasia treated with distraction osteogenesis: a report of two cases

We treated two patients with osteofibrous dysplasia of the tibia using en bloc marginal excision of the lesion and bone transport, a distraction osteogenesis procedure. In one patient, we had performed curettage procedures twice, each time followed by local recurrence and deformity. In contrast, with marginal excision and bone transport using an Ilizarov apparatus, the disease healed. In the other patient, we performed marginal excision and bone transport as the first procedure, which resulted in a healed lesion. In patients with osteofibrous dysplasia requiring treatment by an open method, curettage frequently is followed by local recurrence and deformity. We now prefer marginal excision of the lesion to avoid long-term failures, as in our first case. Distraction osteogenesis has proven useful for restoring structure and function in the affected limb.     

Distraction osteogenesis for treatment of bone loss in the lower extremity

 Distraction osteogenesis has been widely utilized to treat leg length discrepancy, deformity, nonunion, osteomyelitis, and bone loss. It has been found that most difficult conditions can be resolved with this method. This paper introduces the usefulness of distraction osteogenesis for the treatment of nonunion and bone loss after tumor excision. The procedure was found to be extremely effective for the treatment of nonunion accompanied by bone loss and infected nonunion. In particular, the Ilizarov method offers a simultaneous solution for several problems related to nonunion, such as instability, infection, deformity, bone loss, joint contracture, limb length discrepancy, and skin defects. In addition, distraction osteogenesis is safe, useful, and efficient for the treatment of bone loss even after tumor excision. Joint preservation and reconstruction by means of distraction osteogenesis is the most conservative limb-saving surgery available at present. Furthermore, distraction osteogenesis can provide natural limb regeneration. Received: June 24, 2002 Offprint requests to: H. Tsuchiya Presented at the 75th Annual Meeting of the Japanese Orthopaedic Association, Okayama, Japan, May 2002     

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research(dedicated to 100~(th) birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed "limb lengthening and reconstruction surgery". Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal's rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.     

Successful management of complications from distraction osteogenesis after osteosarcoma resection: a case report

We report a complicated case of osteosarcoma of the proximal tibia. A 15-year-old boy was referred to us and underwent distraction osteogenesis reconstruction. We administered preoperative chemotherapy for five cycles. Clinical response was determined to be complete by radiography. Marginal excision was then performed with preservation of the proximal tibial epiphysis. Metaphyseal reconstruction (type 2) was performed with distraction osteogenesis. Postoperative chemotherapy also was administered for five cycles. Two years later, the patient developed a deep infection. He underwent curettage and a pedicle peroneal flap transfer, which did not cure the infection. Infected tissues were excised, and shortening-distraction was carried out with the Ilizarov frame. The infection was cured; however, a leg length discrepancy and deformity resulted from frame instability. Four years after the initial operation, the patient fractured his reconstructed leg in a traffic accident. We performed osteosynthesis, deformity correction, and lengthening with the Ilizarov method. We were able to correct the defects using distraction osteogenesis, eventually restoring normal function. Epiphyseal preservation and reconstruction by distraction osteogenesis can provide an excellent outcome, resulting in a stable reconstruction that functionally restores the native limb. Distraction osteogenesis avoids some complications but may involve others, which require detection and appropriate management.     

Methods to shorten the duration of an external fixator in the management of tibial infections

Massive segmental bone loss due to chronic osteomyelitis represents a considerable challenge to orthopedic surgeons and is a limb threatening condition. The only option available in such a clinical situation is segment transport using the Ilizarov technique of distraction osteogenesis; yet the most common problem in cases of bone transport with the Ilizarov technique in massive bone loss, is the long duration of the fixator. In addition to autologous bone grafting, several mechanical, biologic, and external physical treatment modalities may be employed to promote bone formation and maturation during segment transport in osteomyelitis patients. Mechanical approaches include compressive loading of the distraction regenerate, increased frequency of small increments of distraction, and compression-distraction. Intramedullary nailing and hemicorticotomy can reduce the time in external fixation; however, these techniques are associated with technical difficulties and complications. Exogenous application of low-intensity pulsed ultrasound or pulsed electromagnetic fields may shorten the duration of external fixation. Other promising modalities include diphosphonates, physician-directed use (off-label use) of bone morphogenetic proteins, and local injection of bone marrow aspirate and platelet gel at the osteotomy site. Well-designed clinical studies are needed to establish safe and effective guidelines for various modalities to enhance new bone formation during distraction osteogenesis after segment transfer.     

Ilizarov treatment of tibial nonunions with bone loss

Twenty-five patients aged 19-62 years were treated for tibial nonunions (22 atrophic, three hypertrophic) with bone loss (1-23 cm, mean 6.2 cm) by the Ilizarov technique and fixator. Thirteen had chronic osteomyelitis, 19 had a limb-length discrepancy (2-11 cm), 12 had a bony defect (1-16 cm), and 13 had a deformity. Six had a bone defect with no shortening, 13 had shortening with no defect, and six had both a bone defect and shortening. Nonunion, bone defects, limb shortening, and deformity can all be addressed simultaneously with the Ilizarov apparatus. Bone defects were closed from within without bone grafts by the Ilizarov bone transport technique of sliding a bone fragment internally, producing distraction osteogenesis behind it until the defect is bridged (internal lengthening). Length was reestablished by distraction of a percutaneous corticotomy or through compression and subsequent distraction of the pseudarthrosis site (external lengthening). Distraction osteogenesis resulting from both processes obviated the need for a bone graft in every case. Deformity was corrected by means of hinges on the apparatus. Infection was treated by radical resection of the necrotic bone and internal lengthening to regenerate the excised bone. Union was achieved in all cases. The mean time to union was 13.6 months, but it was only 10.6 months if the time taken for unsuccessful compression-distraction of the nonunion is eliminated from the calculation. The bone results were excellent in 18 cases, good in five, and fair in two based on union in all cases, persistent infection in three, deformity in four, and limb shortening in one. The functional results were excellent in 16 cases, good in seven, fair in one, and poor in one based on return to work and daily activities in all cases, limp in four cases, equinus deformity in five cases, dystrophy in four cases, pain in four cases, and voluntary amputation for neurogenic pain in one case.     

Fibular lengthening by Ilizarov method secondary to shortening by osteochondroma of distal tibia

Osteochondroma is the most common benign bone tumour. They most commonly affect the long tubular bones and almost half of osteochondromata are found around the knee. Osteochondroma arising from the distal metaphysis of the tibia typically result in a valgus deformity of the ankle joint secondary to relative shortening of the fibula. This case describes the use of Ilizarov technique for fibular lengthening following excision of a distal tibial osteochondroma. A 12-year-old girl presented with a 3-year history of a large swelling affecting the lateral aspect of the right distal tibia. Plain radiographs confirmed a large sessile osteochondroma arising from the postero-lateral aspect of the distal tibia with deformity of the fibula and 15 mm of fibular shortening. The patient underwent excision through a postero-lateral approach and subsequent fibular lengthening by Ilizarov technique. The patient made excellent recovery with removal of frame after 21 weeks and had made a full recovery with normal ankle function by 6 months. The Ilizarov method is a commonly accepted method of performing distraction osteogenesis for limb inequalities; however, this is mainly for the tibia, femur and humerus. We are unaware of any previous cases using the Ilizarov method for fibular lengthening. This case demonstrates the success of the Ilizarov method in restoring both fibular length and normal ankle anatomy.     

Tetrafocal leg reconstruction using combined Ilizarov/TSF technique

Treatment of segmental tibial bone defects after high-energy trauma or atrophic nonunion resection is challenging. In the last two decades, distraction osteogenesis Ilizarov bone transport has become a gold standard for the treatment of segmental tibial bone defects and lengthening in spite of the fact that frequent frame modifications and the need for sequential correction of deformities during bone transport are the main limitations of the device itself. The Taylor Spatial Frame applies the concept of the Stewart platform to the standard Ilizarov frame while applying the same principles of distraction osteogenesis postulated by Ilizarov. We report the case of a patient with two problems we could treat simultaneously: an ankle equinus contracture (a consequence of limb leg discrepancy) and infected tibial nonunion and soft-tissue damage complication after plating in a 41A3 type II Gustilo fracture of the left leg.     

The histology of distraction osteogenesis using different external fixators

The local biology of distraction osteogenesis using Ilizarov and Wagner external fixators was compared in unilateral tibial lengthenings in two groups of eight dogs. Serial roentgenograms with histological correlation revealed some basic similarities as well as distinct differences between the two groups. All dogs fully bridged the experimental gap by intramembranous ossification. Subtle histological changes in the alignment of collagen bundles and subsequent ossification reflected the mechanical configuration of each fixator. The multiplanar, full-pin Ilizarov system delivered concentric load to the site of osteogenesis, inducing perfectly parallel columns of new bone. The uniplanar, one-half pin Wagner system induced angulation of the collagen and subsequent bone columns on the basis of eccentric load to the osteogenic interface. Despite a significant difference in axial rigidity, the Ilizarov and Wagner external fixators induced osteogenesis of equal volume.     

Reverse Sural Flap with Bifocal Ilizarov Technique for Tibial Osteomyelitis with Bone and Soft Tissue Defects

Tibial osteomyelitis, in association with bone loss and a soft tissue defect, poses a significant reconstructive challenge, especially in high-risk patients. We describe a case of methicillin-resistant Staphylococcus aureus tibial osteomyelitis with intercalary bone loss successfully managed with bifocal Ilizarov compression osteogenesis at the bone resection site and proximal distraction osteogenesis, accompanied by a reverse sural fasciocutaneous flap performed with a delayed technique. When free tissue transfer is not a reconstructive option owing to medical comorbidities or patient refusal, the reverse sural flap combined with bifocal Ilizarov compression and distraction osteogenesis can provide a reconstructive option to achieve limb salvage for these challenging cases.     

Reconstruction of segmental bone defects due to chronic osteomyelitis with use of an external fixator and an intramedullary nail

BACKGROUND: Callus distraction over an intramedullary nail is a rarely used technique for the reconstruction of intercalary defects of the femur and tibia after radical débridement of chronic osteomyelitic foci. The aim of this study was to summarize our experience with distraction osteogenesis performed with an external fixator combined with an intramedullary nail for the treatment of bone defects and limb-shortening resulting from radical débridement of chronic osteomyelitis. METHODS: Thirteen patients who ranged in age from eighteen to sixty-three years underwent radical débridement to treat a nonunion associated with chronic osteomyelitis of the tibia (seven patients) and femur (six patients). The lesions were classified, according to the Cierny-Mader classification system, as type IVA (nine) and type IVB (four). The resulting segmental defects and any limb-length discrepancy were then reconstructed with use of distraction osteogenesis over an intramedullary nail. Two patients required a local gastrocnemius flap. Free nonvascularized fibular grafts were added to the distraction site for augmentation of a femoral defect at the time of external fixator removal and locking of the nail in two patients. At the time of the latest follow-up, functional and radiographic results were evaluated with use of the criteria of Paley et al. RESULTS: The mean size of the defect was 10 cm (range, 6 to 13 cm) in the femur and 7 cm (range, 5 to 10 cm) in the tibia. The mean external fixator index was 13.5 days per centimeter, the consolidation index was 31.7 days/cm, and the mean time to union at the docking site was nine months (range, five to sixteen months). At a mean follow-up of 47.3 months, eleven of the thirteen patients had an excellent result in terms of both bone and functional assessment. There were two recurrences of infection necessitating nail removal. These patients underwent revision with an Ilizarov fixator. Subsequently, the infection was controlled and the nonunions healed. CONCLUSIONS: This combined method may prove to be an improvement on the classic techniques for the treatment of a nonunion of a long bone associated with chronic osteomyelitis, in terms of external fixation period and consolidation index. The earlier removal of the external fixator is associated with increased patient comfort, a decreased complication rate, and a convenient and rapid rehabilitation.     

Limb Salvage by Distraction Osteogenesis for Distal Tibial Osteosarcoma in a Young Child: A Case Report

Under the effective chemotherapy protocol, physeal distraction could be used as an effective limb salvage in the growing children with lower‐limb malignant metaphyseal bone tumours and could actively prevent leg length discrepancy or malalignment that profoundly affects function. In this paper, we report a 7‐year‐old boy with right distal tibial osteosarcoma but not yet invaded the epiphysis, which underwent surgical treatment after effective chemotherapy. The surgical procedure included two phases: epiphysiolysis (physeal distraction) and en‐bloc resection of tumor and distraction osteogenesis. In the first phase, after osteotomy of the proximal fibula was performed, two Ilizarov rings were attached to the proximal tibia and one Ilizarov ring was applied to the distal tibia. At same time, U‐shape ring as an important external fixator was been used in the axis of rotation of the ankle joint in order to balance the stress from the surrounding tissues, increase distracting stabilization and prevent the deformity or contracture of ankle joint. In the second phase, the tumor bone (5.7 cm) was en bloc resected by diaphyseal osteotomy. Distraction osteogenesis was commenced 1 week postoperatively at a rate of 1 mm twice a day. The patient was reviewed by X‐ray intermittently. The new bone was formed and the entire bone defect was covered in four months after the operation. Doxorubicin and cisplatin as the neoadjuvant chemotherapy protocol are effective to osteosarcoma and chemotherapy process did not adversely affect the union. Through this technique, the right distal tibial epiphysis was reserved successfully. At the last follow‐up, there are no local recurrence or metastasis and we achieve to prevent leg length discrepancy or malalignment that profoundly affects function.     

多种技术联用治疗难治性骨髓炎的疗效分析

目的探讨应用Ilizarov骨搬移技术联合抗生素骨水泥片技术、Masquelet技术(膜诱导技术)等技术治疗长骨慢性骨髓炎的临床疗效。 方法回顾性分析2012年6月至2016年10月,新疆军区总医院创伤骨科联合应用病灶清除、Ilizarov技术、抗生素骨水泥片填充技术、膜诱导成骨技术、远端缓慢回缩技术等技术治疗的20例股骨、胫骨慢性骨髓炎和感染性骨不连患者。纳入标准：慢性骨髓炎合并骨不连或骨缺损的患者;经常规治疗效果差的患者;无影响治疗的合并症;病例资料完整的患者。排除标准：不符合疾病的纳入标准;存在活动性结核、肿瘤等疾病的患者;依从性差、不能按照医生要求调整外固定架的患者。记录上述患者是否需行皮瓣转移手术、带外固定架时间、全负重时间及是否出现复发情况。 结果所有患者均得到随访,随访时间平均(29.2±1.8)个月。均获得了良好的骨性愈合,所治疗患者感染均得到一期愈合,创面无需皮瓣转移或植皮均得到良好闭合,骨搬移结合处愈合良好。患者骨搬移长度平均(7.3±1.8)cm。所有患者未出现神经损伤,其中有两例患者术前存在腓总神经损伤,术后在骨搬移过程中出现不同程度的神经功能恢复。 结论应用Ilizarov的骨搬移和骨延长技术能有效治疗彻底清创后的骨缺损或肢体短缩问题,保证彻底清创、促进局部血运改善、不需要皮瓣覆盖也能愈合创面;抗生素骨水泥片起到占位器和膜诱导作用促进成骨;远端缓慢回缩有利于骨端愈合;多种方法联合应用,有效地提高了难治性骨髓炎的治愈率,是一种安全有效的治疗方法。     

Daily subcutaneous Teriparatide injection increased bone mineral density of newly formed bone after tibia distraction osteogenesis,a randomized study

Long bone defects are often treated by bone segment transport with the Ilizarov method requiring months spent with fixator mounted until bony consolidation of the newly formed bone. Shortening of consolidation would allow earlier fixator removal and earlier return to work. In pre-clinical studies parathyroid hormone, increased bone mineral density and mechanical properties of regenerate bone formed during distraction osteogenesis. Clinical studies showed that Teriparatide accelerated fracture healing in patients with osteoporotic fracture of the pelvis, hip, wrist and shoulder. We hypothesized that rhPTH(1-34) (Teriparatide) administered to patients who had undergone distraction osteogenesis, would increase mineralization of the regenerate formed during the consolidation phase.Sixteen patients with tibial defects after infection, underwent bone segment transport and at the time of docking the transport segment, were randomized to 8 weeks treatment with daily subcutaneous 0.20-μg Teriparatide injection followed by 8 weeks with no treatment, or to 8 weeks with no treatment followed by 8 weeks with daily subcutaneous 0.20 μg Teriparatide injection. Bone mineral density (BMD) of the regenerate was measured at the time of docking, 8 weeks after docking and 16 weeks after docking with DEXA. Functional evaluation was performed after one year. The design was a cross-over study.Overall BMD increased 0.14 g/cm² in 8 weeks without treatment and 0.33 g/cm² under Teriparatide treatment. After adjustment for a potential phase difference, 8 weeks of Teriparatide treatment led to an additional 0.19 g/cm² BMD increase (95%-CI:[0.11,0.28], p < 0.001). The ratio of the BMD increase between the two treatments was 0.33/0.14 = 2.43 (CI: [1.21,3.65]).Teriparatide treatment during the consolidation phase of distraction osteogenesis doubled the mineralization rate of the regenerate when compared to no treatment.     

Benefits of Ilizarov automated bone distraction for nerves and articular cartilage in experimental leg lengthening

AIM To determine peculiarities of tissue responses to manual and automated Ilizarov bone distraction in nerves and articular cartilage.METHODS Twenty-nine dogs were divided in two experimental groups: Group M-leg lengthening with manual distraction(1 mm/d in 4 steps), Group A-automated distraction(1 mm/d in 60 steps) and intact group. Animals were euthanized at the end of distraction, at 30 th day of fixation in apparatus and 30 d after the fixator removal. M-responses in gastrocnemius and tibialis anterior muscles were recorded, numerical histology of peronealand tibialis nerves and knee cartilage semi-thin sections, scanning electron microscopy and X-ray electron probe microanalysis were performed.RESULTS Better restoration of M-response amplitudes in leg muscles was noted in A-group. Fibrosis of epineurium with adipocytes loss in peroneal nerve, subperineurial edema and fibrosis of endoneurium in some fascicles of both nerves were noted only in M-group, shares of nerve fibers with atrophic and degenerative changes were bigger in M-group than in A-group. At the end of experiment morphometric parameters of nerve fibers in peroneal nerve were comparable with intact nerve only in A-group. Quantitative parameters of articular cartilage(thickness, volumetric densities of chondrocytes, percentages of isogenic clusters and empty cellular lacunas, contents of sulfur and calcium) were badly changed in M-group and less changed in A-group.CONCLUSION Automated Ilizarov distraction is more safe method of orthopedic leg lengthening than manual distraction in points of nervous fibers survival and articular cartilage arthrotic changes.