The ipsilateral and contralateral fibulae have been

Ipsilateral vascularised fibular transport for massive defects of the tibia R. M. Atkins, P. Madhavan, J. Sudhakar, D. Whitwell From the Bristol Royal Infirmary, Bristol, England The ipsilateral and contralateral fibulae have been used as a vascularised bone graft for loss of tibial bone usually by methods which have involved specialised microvascular techniques to preserve or re-establish the blood supply. We have developed a method of tibialisation of the fibula using the Ilizarov fixator system, ipsilateral vascularised fibular transport (IVFT), and have used it in five patients with massive loss of tibial bone after treatment of an open fracture, infected nonunion or chronic osteomyelitis. All had successful transport, proximal and distal union, and hypertrophy of the graft without fracture. One developed a squamous-cell carcinoma which ultimately required amputation of the limb. The advantage of IVFT is that the fibular segment retains its vascularity without the need for microvascular dissection or anastomoses. Superiosteal formation of new bone occurs if the tibial periosteal bed is retained. Other procedures such as corticotomy and lengthening can be carried out concurrently. J Bone Joint Surg [Br] 1999;81-B:1035-40. Received 11 March 1999; Accepted after revision 24 May 1999 A number of surgical methods have been used for salvage of the limb when there is a defect in the tibia of more than 6 cm, with a usable fibula, following trauma, infection or tumour (type-4 bone loss). 1 The ipsilateral and contralateral fibulae have been used as substitutes, both as vascular and avascular grafts. We have obtained good results with the circular external fixator of Ilizarov in the treatment of infected nonunion, segmental bone loss and acute high-energy open fractures of the tibia. R. M. Atkins, MA, DM, FRCS, Consultant Orthopaedic Surgeon P. Madhavan, FRCS Ed (Orth), Specialist Registrar J. Sudhakar, FRCS, Research Registrar D. Whitwell, FRCS, Research Registrar Department of Orthopaedic Surgery, Bristol Royal Infirmary, Bristol BS2 8HW, UK. Correspondence should be sent to Mr R. M. Atkins. 1999 British Editorial Society of Bone and Joint Surgery 0301-620X/99/610001 $2.00 We now describe a method of replacement of the defect in the tibia by a portion of the fibula, using the Ilizarov fixator system, in which the fibular segment retains its vascularity without the need for microvascular anastomoses or dissection of the bone, blood vessels or muscles. Patients and Methods Between 1993 and 1997 five patients had ipsilateral vascularised fibular transport (IVFT) for type-4 bone loss of the tibia (Table I). The limb was first stabilised with an Ilizarov frame of the desired configuration (Figs 1 to 3). The tibial deficiency is usually a result of surgical excision of avascular bone or infected sequestrum, in which care has been taken to keep the excision subperiosteal, or acute bone loss after trauma. The length of the defect was measured and any overlying wounds debrided. The bone loss can be replaced by IVFT alone or by using a corticotomy of the proximal or distal tibia, which is performed concomitantly or at a later stage. Using an image intensifier, a segment of fibula of preplanned length, adjacent to the defect, was transfixed from the posterolateral to anteromedial position by two pulling wires which have stoppers such as olives or kinks. These wires were at least 1 cm from the proposed sites of the osteotomies, and passed through the centre of the tibial bed (Fig. 4). The fibula was then osteotomised, either by using a wellcooled saw or by multiple drill holes and an osteotome, taking care to ensure that the length was adequate. It was approached either through limited separate posterolateral incisions or the posterolateral aspect of the cavity of the excised tibia. If present, a coexistent fibular fracture was used as a substitute for the osteotomy. Each wire was then attached to the anteromedial aspect of the frame to motors constructed in a standard fashion. The fibula was transported gradually into the bed of the tibia. The rate depended on the suppleness of the soft tissues and was usually 2 to 3 mm per day, divided into four equal amounts. Once the fibula was well centred in the tibial bed, the proximal and distal ends of the tibia were compressed on to the transported segment to anchor it. After transport was completed, weight-bearing was allowed to encourage bone union and fibular hypertrophy. VOL. 81-B, NO. 6, NOVEMBER 1999 1035

1036 R. M. ATKINS, P. MADHAVAN, J. SUDHAKAR, D. WHITWELL Table I. Clinical details and results for the five patients who had IVFT Age Defect Time to union Case (yr) Gender Diagnosis Reconstructive procedures (cm) (wk) 1 66 M Chronic osteomyelitis of the tibia IVFT 18 13 with squamous-cell carcinoma of skin 2 53 F Infected nonunion after IIIB open IVFT and concurrent distal 16 Proximal, 15 fracture in a bomb blast; failed corticotomy with lengthening Distal, 35 DCIA flap 3 24 M IIIB open fracture of the tibia with IVFT and concurrent proximal 12 Proximal, 12 bone loss and partially failed flap corticotomy with lengthening Distal, 17 4 26 M IIIB open fracture of the tibia with IVFT and subsequent proximal 18 21 bone loss and infection corticotomy and lengthening 5 53 M IIIB open fracture of the tibia with IVFT 13 Proximal, 12 Schatzker VI fracture of the Distal, 12 tibial plateau with deep infection Results In all five patients, the transferred fibula united proximally and distally, without major complications (Fig. 5, Table I). The range of time to union was 12 to 35 weeks. Two different bone-forming processes were seen. First, all fibular segments showed hypertrophy after union. Secondly, all tibial beds except one showed subperiosteal formation of new bone around the fibular segment, presumably from the intact tibial periosteal sleeve (Figs 5 to 7). All had satisfactory healing of soft tissue over the tibia. None had fractures of the graft. Four patients can actively invert, evert and dorsiflex the foot, demonstrating adequate function of the peroneal, tibialis posterior and tibialis anterior muscles. All movement is considerably less than on the opposite normal side. One patient (case 2) has a dorsiflexed great toe with no activity of flexor hallucis longus. Another (case 1), who had had chronic osteomyelitis of the tibia for over 40 years, had IVFT after resection. Routine histopathological examination of the skin showed features suggestive of squamous-cell carcinoma distally. Further resection of the distal skin, periosteal bed and adjacent tibia was carried out leaving margins free from tumour. Union occurred proximally and distally. Graft hypertrophy was present and the soft tissues healed. No subperiosteal formation of new bone was seen. Unfortunately, five months later, he developed a squamous-cell carcinoma at the distal end of the previous wound which required a below-knee amputation. Discussion Fig. 1a Fig. 1b AP and lateral radiographs showing grade-iiib open fracture of the tibia and fibula. The blood supply to the shaft of the fibula comes from a branch of the peroneal artery. It usually enters the posterior aspect of the fibula in the middle third, 7 cm below its origin. It also gives off multiple branches to the periosteum along its extraosseous course. These usually traverse the flexor hallucis longus muscle before arborising on bone. 2 Tibialisation of the fibula was first described by Albert in 1877 to achieve fusion between the femur and distal tibia in a patient with congenital absence of the proximal tibia. 3 Since then, four methods with a number of variations have been described. All have their complications and limitations. Method 1. The ipsilateral or contralateral fibula is removed and used as a strut of avascular bone. This graft is osteoconductive and may be osteoinductive, but is extremely unlikely to have true osteogenic potential. The results are not as good as in vascularised grafts. The rates of fracture THE JOURNAL OF BONE AND JOINT SURGERY

IPSILATERAL VASCULARISED FIBULAR TRANSPORT FOR MASSIVE DEFECTS OF THE TIBIA 1037 Fig. 2 AP radiograph after initial debridement, external fixation and failed microvascular flap. A coexistent ankle fracture was internally fixed. Fig. 3 AP radiograph after final debridement of bone, application of Ilizarov ring fixator, IVFT and proximal corticotomy and fibulectomy. In this case, kinked wires were used for IVFT. Fig. 4a Fig. 4b AP and lateral radiographs showing the IVFT in position. of the graft and of infection are higher. 4 There is also the potential morbidity of surgery on the often normal, contralateral leg. This method is rarely used. Method 2. This was first described by Huntington. 5,6 The ipsilateral fibula is osteotomised and mobilised medially with some of the muscle attachments intact after dissecting VOL. 81-B, NO. 6, NOVEMBER 1999

1038 R. M. ATKINS, P. MADHAVAN, J. SUDHAKAR, D. WHITWELL Fig. 5a Fig. 5b AP and lateral radiographs showing proximal and distal union of the fibular segment and subperiosteal formation of new bone in the tibial bed. Fig. 6a Fig. 6b AP and lateral radiographs showing the hypertrophied, united fibular segment. off the others. Vascularity of the graft is usually maintained. Mobilisation can be carried out either in one or two stages, but can be severely restricted by previous inflammation in the area. The lateral aspect of the leg must be healthy. Zahiri, Zahiri and Tehrany 7 successfully used a modification of this method to treat chronic osteomyelitis of the entire tibial shaft in nine children. Method 3. This technique was originally suggested by THE JOURNAL OF BONE AND JOINT SURGERY

IPSILATERAL VASCULARISED FIBULAR TRANSPORT FOR MASSIVE DEFECTS OF THE TIBIA 1039 Fig. 7a Fig. 7b AP and lateral radiographs taken approximately 14 months after injury showing the entire leg with mature proximal bone regenerate and distal hypertrophied IVFT. Chacha, Ahmed and Daruwalla. 8 The vascular supply of the ipsilateral fibula is isolated as a loop and the bone is transposed into the defect as one or two segments. A number of variations have since been described to fill tibial defects which may be proximal, central or distal in position. All require extensive dissection of the graft and its blood supply. Previous local inflammation increases the risk of vascular damage. Khan, Downing and Henry 9 used this method in eight patients with segmental tibial defects following Gustilo grade-iii open fractures and seven were satisfactory. Method 4. The contralateral or, rarely, the ipsilateral fibula is harvested with the nutrient vessels, transferred into the defect and its vascularity re-established by microvascular anastomoses. This technique may involve removal of the graft from a normal limb and was first described in man by Taylor, Miller and Ham. 10 It requires a highly-skilled surgical team and has a small, but definite, risk of failure. Morbidity at the donor site may be considerable and sometimes increases with time. 11,12 In methods 3 and 4 it is recommended that an angiogram be done before the graft is harvested. 2,13 In some cases the harvested vessel was found to be the sole feeder to the foot, the fibula had no demonstrable nutrient vessels, or the nutrient artery entered the fibula away from its usual position. The use of a circular external fixator with fine wires after methods 3 and 4 can cause irreparable damage to the vessels of the graft. Circular external fixation carried out before the microvascular anastomoses can make the latter procedure considerably more difficult. Hence, the graft is usually fixed by screws or Kirschner wires and spanning uniaxial fixators. Such fixation does not allow early weightbearing and subsequent fibular hypertrophy. Ilizarov described two methods for treating marked defects with his fine-wire fixator. 14 In the first, the fibular segment is translated medially, creating a proximal and distal, side-to-side tibiofibular synostosis. In the second method, the fibula is split longitudinally and transverse distraction osteogenesis is performed. This technique is complex and no mention is made of the clinical results. Our technique has several advantages. Operative dissection of the fibula is minimal. It remains well vascularised as both sources of blood supply are neither defined nor dissected. Muscle attachments are maintained without dissection. The tibial periosteal sleeve, if retained, allows profuse formation of new bone around the transported section which contributes to fibular hypertrophy and bone strength. The fibular segment is central and is held by the tibial remnants in a mechanically advantageous position in the line of the axis of the tibia. The Ilizarov fixator allows stability and longitudinal compression to be established without internal fixation. Weight-bearing can begin almost immediately after surgery and the proximal and distal joints mobilised satisfactorily. Further limb lengthening may be carried out through a separate corticotomy of either the proximal or distal tibial remnant. The opposite limb is untouched. Based on our results we feel that IVFT is a satisfactory method of tibialisation of the fibula in patients with large segmental type-4 defects and a usable ipsilateral fibula. 1 We do not recommend it for smaller segmental defects (types 1, 2 and 3) 1 since other methods such as corticotomy with bone transport or lengthening are more effective. Although none of the authors have received or will receive benefits for personal or professional use from a commercial party related directly or indirectly to the subject of this article, benefits have been or will be received but are directed solely to a research fund, educational institution, or other non-profit institution with which one or more of the authors is associated. References 1. May JW Jr, Jupiter JB, Weiland AJ, Byrd HS. Current concepts review: Clinical classification of post-traumatic tibial osteomyelitis. J Bone Joint Surg [Am]1989;71-A:1422-8. 2. Ruch DS, Koman LA. The fibula-flexor hallucis longus osteomuscular flap. J Bone Joint Surg [Br] 1997;79-B:964-8. 3. Hertel R, Pisan M, Jakob R. Use of the ipsilateral vascularised fibula for tibial reconstruction. J Bone Joint Surg [Br] 1995;77-B:914-9. 4. Yadav SS. Dual-fibular grafting for massive bone gaps in the lower extremity. J Bone Joint Surg [Am] 1990;72-A:486-94. VOL. 81-B, NO. 6, NOVEMBER 1999

1040 R. M. ATKINS, P. MADHAVAN, J. SUDHAKAR, D. WHITWELL 5. Huntington TW. Case of bone transference. Use of a segment of fibula to supply a defect in the tibia. Ann Surg 1905;XLI:249-51. 6. Agiza ARH. Treatment of tibial osteomyelitic defects and infected pseudarthroses by the Huntington fibular transference operation. J Bone Joint Surg [Am] 1981;63-A:814-9. 7. Zahiri CA, Zahiri H, Tehrany F. Limb salvage in advanced chronic osteomyelitis in children. Int Orthop 1997;21:249-52. 8. Chacha PB, Ahmed M, Daruwalla JS. Vascular pedicle graft of the ipsilateral fibula for non-union of the tibia with a large defect: an experimental and clinical study. J Bone Joint Surg [Br] 1981;63-B: 244-53. 9. Khan MZ, Downing ND, Henry AP. Tibial reconstruction by ipsilateral vascularised fibular transfer. Injury 1996;27:651-4. 10. Taylor GI, Miller GD, Ham FJ. The free vascularised bone graft: a clinical extension of microvascular techniques. Plast Reconstr Surg 1975;55:533-44. 11. Shpitzer T, Neligan P, Boyd B, et al. Leg morbidity and function following fibular free flap harvest. Ann Plast Surg 1997;38: 460-4. 12. Vail TP, Urbaniak JR. Donor-site morbidity with use of vascularized autogenous fibular grafts. J Bone Joint Surg [Am] 1996;78-A: 204-12. 13. Blackwell KE. Donor site evaluation for fibula free flap transfer. Am J Otolaryngol 1998;19:89-95. 14. Ilizarov GA. Pseudoarthroses and defects of long tubular bones: treatment of marked defects. In: Ilizarov GA, ed. Transosseous osteosynthesis. Berlin, etc: Springer-Verlag, 1992:478-9. THE JOURNAL OF BONE AND JOINT SURGERY