Infected nonunion of the long bones

BACKGROUND: Although definitions vary, infected nonunion has been defined as a state of failure of union and persistence of infection at the fracture site for 6 to 8 months.>). Infected nonunions of the supracondylar region of the femur are uncommon and are mostly due to a severe open fracture with extensive comminution and segmental bone loss or after internal fixation of a comminuted closed fracture.Associated factors include exposed bone devoid of vascularized periosteal coverage for more than 6 weeks, purulent discharge, a positive bacteriological culture from the depth of the wound, and histologic evidence of necrotic bone containing empty lacunae. Soft-tissue loss with multiple sinuses, osteomyelitis, osteopenia, complex deformities with limb-length inequality, stiffness of the adjacent joint, polybacterial multidrug-resistant infection, and smoking all complicate treatment and recovery.Although uncommon in incidence, infected nonunions of the long bones present a great challenge to the orthopaedic surgeon in providing optimal treatment of this entity. To give direction to the optimal strategy, this systematic review was performed. OBJECTIVE: We aimed to review the highest level of available evidence on the operative management of infected nonunions of the long bones.     

Cement spacers with antibiotics for the treatment of posttraumatic infected nonunions and bone defects of the upper extremity

Treatment of patients with posttraumatic infected nonunions or highly contaminated open fractures with segmental bone loss of the long bones of the upper extremity is demanding. The use of a 2-stage reconstruction technique, being the first stage characterized by thorough debridement, copious lavage, soft tissue coverage, and placement of a cement spacer with antibiotics at the infected site, and the second stage by cement spacer removal, internal fixation, and placement of bone graft with local antibiotics, is presented. We carried out this technique in 20 cases, in 12 cases the cement was molded to fit the defect and placed as a solid interposition mass, in 3 cases it was placed lateral to the affected bone, and in the remaining 5 cases a Rush nail covered with a cement mantle was used. Follow-up averaged 18 months. All nonunions and fractures healed after an average of 5 months. Disabilities of the arm, shoulder, and hand (DASH) score at last follow-up in nonunions averaged 14 points and 21 points in bone losses. Although generally 2 surgical procedures are needed, 1 to cure or prevent infection and another to achieve bony union, this approach for complex open fractures with segmental bone loss and for infected nonunions of the long bones of the upper extremity represents a valid treatment alternative.     

Management of difficult lower extremity fractures and nonunions

Difficult fractures and nonunions of the lower extremities are defined as compound fractures with soft-tissue loss, segmental bone fractures, and infected nonunions. A variety of methods for managing these defects are presented, including the use of modern fixation techniques and the application of highly vascularized bone and soft tissues. Vascularized bone grafts play a significant role in the treatment of difficult fractures that previously would have required amputation.     

Diaphysäre Oberarmpseudarthrosen – operative und konservative Behandlung

Operative treatment of acute humeral shaft fractures represents a major source of nonunions. The analysis of the biomechanical and biological causes of diaphyseal nonunions of the humerus is a prerequisite for the successful treatment of ununited humeral shaft fractures. Biologically active nonunions heal after debridement and correction of deformities with an improvement of mechanical stability, preferably by fixation with a compression plate. In atrophic nonunions, the restoration of the biologic capacity to restore osteogenesis by bone grafting is additionally necessary. The treatment of synovial pseudarthrosis and infected nonunion requires removal of bone and debridement of synovial and infected avascular tissues, respectively. Intramedullary nails to improve mechanical stability and nonoperative treatment with extracorporeal shock waves should only be used in a few special cases which do not have any severe deformities.     

Infected nonunion of the long bones

The problems in infected nonunion include multiple sinuses, osteomyelitis, bone and soft tissue loss, osteopenia, adjacent joint stiffness, complex deformities, limb-length inequalities, and multidrug-resistant polybacterial infection. Bone gap and active infection are the crucial factors relating to treatment and prognosis. Gaps larger than 4 cm likely cannot be effectively bridged by corticocancellous bone grafting. If the limb has intact distal circulation and sensation, limb salvage and reconstruction generally is preferable to amputation. The fracture generally unites if adequate debridement of the nonunion site is done with fracture stabilization and bone grafting. We reviewed 42 consecutive patients with infected nonunion of the long bones. These patients have been categorized into two groups. Type A is infected nonunion of long bones with nondraining (quiescent) infection, with or without implant in situ; Type B is infected nonunion of long bones with draining (active) infection. Both are classified further into two subtypes: 1) nonunion with a bone gap smaller than 4 cm or 2) nonunion with a bone gap larger than 4 cm. Single-stage debridement and bone grafting with fracture stabilization are the methods of choice for Type A1 infected nonunions. Adequate debridement, fracture stabilization, and second-stage bone grafting gives desirable results in Type B1 infected nonunions. Distraction histiogenesis is the preferred procedure for Type A2 and B2. The autogenous nonvascularized fibular graft, posterolateral bone grafting for the tibia, and centralization of the ulna over distal radial remnant (single bone forearm) may be good treatment options in selected cases.     

Percutaneous autologous bone marrow transplantation for nonunion of the femur.

Percutaneous bone marrow injections were performed on 7 nonunions of the femur. There were 6 hypervascular nonunions and one avascular nonunion. Two nonunions presented with active infections. One other patient had a history of infection which had subsided. One nonunion received the injection twice. After the site of nonunion was curetted and the bone surface was scored, 150 ml of bone marrow aspirated from the iliac bone was injected. Complete union occurred in 4 patients within 9 months; all of them were uninfected hypervascular nonunions following intramedullary nail fixation. One nonunion with a bone defect united partially leaving a 1 x 1 cm defect. The two infected femoral nonunions failed to unite. The results show that percutaneous autologous bone marrow injection for femoral nonunions can be considered for uninfected hypervascular nonunions following intramedullary nail fixation. In these cases stimulation of healing processes of fracture leading to consolidation can be expected from bone marrow injection. However, femoral nonunion with an active infection and loss of fixation is considered to be a contraindication for this technique.     

The treatment of infected nonunions and segmental defects of the tibia by the methods of Ilizarov.

Circular external fixation using the Ilizarov apparatus combined with internal bone transport or compression-distraction techniques were used to treat 28 patients with infected nonunions or segmental bone loss of the tibia. There were 22 males and six females with an average age of 34 years (range, 17-58 years). Six of 28 patients had infected tibial nonunions associated with hemicircumferential bone loss. These tibiae were treated by anterior hemicircumferential corticotomy and partial bone fragment internal transport. Fifteen of the remaining 22 patients had an average of 4 cm of segmental bone loss (range, 2-7 cm). Seven patients without shortening or defect had infected nonunions associated with extensive diaphyseal sequestrae. These nonunions were treated by en bloc resection of the diaphyseal shaft and internal bone transport. All patients healed their infected extremities without the addition of cancellous bone graft, microvascular fibular, or soft-tissue grafting. Preoperative shortening was present in 13 of 28 patients. Regenerate new bone formation averaged 6 cm (range, 1.5-22 cm). Postoperative antibiotics were not administered in 21 of 28 patients. In seven patients, antibiotics were given for ten days after en bloc resection of the diaphyseal sequestrae. Equal limb length was maintained in 21 extremities, within 1 cm in five tibiae and less than 3 cm in two tibiae. Functional results were good to excellent in 21, fair in six, and poor in one. The application of Ilizarov techniques to diaphyseal infected nonunions and segmental defects is very encouraging. It may prove to be an excellent technique for future management of resistant diaphyseal infections of bone.     

Infected nonunions of long bones of the upper extremity: staged reconstruction using polymethylmethacrylate and bone graft impregnated with antibiotics

This case series evaluates 12 patients presenting posttraumatic infected nonunions affecting long bones of the upper extremity, treated with staged reconstruction using polymethylmethacrylate spacers with antibiotics in the first stage and bone graft impregnated with antibiotics in the definitive surgical procedure. Five nonunions affected the humerus, four the ulna and three the radius. All nonunions were atrophic. Patient’s age averaged 35.9 years. The size of the bony defect averaged 2.8 cm. Time between original trauma and revision surgery averaged 9.6 months. Follow-up averaged 19 months. All nonunions healed after an average of 5 months. DASH score at last follow-up averaged 15 points. Although two surgical procedures are needed, one to cure infection and another to achieve bony union, this approach for posttraumatic infected nonunions of long bones of the upper extremities represents a valid treatment alternative.     

Ilizarov treatment of tibial nonunions results in 16 cases

Treatment with the Ilizarov technique was performed in 16 patients with complex tibial nonunions. Two years post treatment the functional stage and patient satisfaction were recorded. There were 4 hypertrophic, 3 atrophic and 9 infected nonunions. Eleven patients had segmental bone loss. Fifteen nonunions united, and limb length discrepancy was reduced within 1.5 cm of the contralateral leg. Average time in the frame was 182 days. Fifteen of the 16 patients were satisfied with the treatment. One patient demanded an amputation after 3 months of treatment, despite good signs of healing. There were no refractures or recurrent infections. In conclusion the Ilizarov technique for complex nonunions has a high rate of success in achieving union and eradicating infection, bone loss and malalignment. The treatment is demanding both to the surgeon and to the patient, but we strongly recommend the Ilizarov treatment for tibial nonunion, especially in cases with chronic infection and severe bone loss.     

Double-barrel free fibula flap for treatment of infected nonunion of both forearm bones

Free vascularized bone transfer is a viable treatment option for extensive bony defects greater than 6 to 8 cm involving scarred, poorly vascularized, or infected recipient beds, such as in chronically infected nonunion of the radius and ulna treated with a double-barrel free fibula flap. Both patients reported here experienced bony union with significant resolution of their symptoms. Although range of motion improved following an aggressive physical therapy regimen, pronation was adversely affected. Chronic infected nonunions or nonunions from radionecrosis involving large segmental defects of both forearm bones are a truly unique challenge and must be treated aggressively to ensure any useful long term function of the injured limb.     

Infected nonunion of the tibia

The treatment of infected nonunited fractures of the tibia using the techniques of Ilizarov was compared with autogenous cancellous bone graft application under a well vascularized soft tissue envelope. There were 10 patients in the Ilizarov group and 17 in the bone graft group. Soft tissue coverage with a free vascularized or a rotational muscle flap was used more frequently among the patients having bone graft (71%) than the Ilizarov group (30%). All 27 patients had bony defects (average, 3.7 cm; range, 1-18 cm). At an average followup of 6 years, 26 patients had a functional limb, and one patient (Ilizarov group) ultimately required a below knee amputation. Three patients in each group required a second plate and bone graft procedure to gain union. Infection persisted in four patients (all in the Ilizarov group). If a well vascularized soft tissue envelope is present (particularly after flap coverage), bone grafting procedures are safe and efficacious. The Ilizarov technique may be best suited for the treatment of very proximal or distal metaphyseal nonunions and nonunions associated with large leg length discrepancies.     

Diaphysäre Humeruspseudarthrosen

The development of humerus nonunion is dependent on the type of fracture, the extent of soft tissue stripping during surgery, the stability of the osteosynthesis, and multiple patient-dependent factors. Treatment should focus on nonunion pathogenesis. The gold standard for the treatment of oligotrophic, atrophic and infected nonunions is radical resection of the nonunion tissue, bone grafting and plate fixation, preferentially using locking plates. Reaming bone graft and stabilization with intramedullary (i.m.) nailing is utilized in hypertrophic nonunion. Since 1993, we have followed-up 51 patients after surgical treatment for humeral shaft nonunion. In eight of 35 cases (22.8%) treated with i.m. nailing, bone healing was not achieved, whereas in all 14 cases of nonunion treated with plate osteosynthesis bone healing occurred. Evaluation of failure in healing humeral shaft nonunion using the i.m. nailing technique revealed that the i.m. nail specifically designed to treat humeral shaft fractures showed several biomechanical and biological deficits for the treatment of nonunions. The major reason for failure in bone healing was a lack of bone grafting that is essential for osteoinduction in oligotrophic nonunions, loosening of locking screws, and unstable small implants.     

Composite implant of native bovine bone morphogenetic protein (BMP), collagen carrier and biocoral in the treatment of resistant ulnar nonunions: report of five preliminary cases

Introduction Bone morphogenetic protein (BMP) has been shown to induce bone formation and union in long bone defects and nonunions. There are, however, no previous reports of BMP being used for ulnar nonunions. We report on five cases of resistant ulnar nonunions treated with a composite implant consisting of a biocoral frame, collagen carrier, and bovine BMP.Materials and methods Four diaphyseal and one olecranon ulnar nonunions were treated using BMP/coral implant combined with internal fixation. Additional autografting was used in three cases. All of the cases were challenging in their own ways: Three of the patients had been operated on earlier for their nonunion without success, one had a 40 mm bone loss, and one had a 9-month-old untreated olecranon fracture. After excision of the sclerotic surfaces of the nonunion, the gap was filled with autograft and a composite implant containing BMP. Fixation was done with a compression plate in the diaphyseal nonunions and with a tension band in the olecranon nonunion.Results Solid union was achieved in all five cases. No infections or other adverse effects were encountered.Conclusion These preliminary results suggest that BMP-containing implants might be a feasible alternative or superior to autografting in the treatment of resistant ulnar nonunions.     

Massive bone defects of the upper limb: reconstruction by vascularized bone transfer

Vascularized bone transfer is increasingly recognized as a very useful and versatile technique for reconstructing massive bone defects in the upper limb or in patients with especially challenging conditions, such as infected nonunions and nonunions associated with radionecrosis of bone. It is especially indicated for the humerus and shoulder region with more selected applications in the forearm or wrist. Although technically challenging, the outcomes of this procedure justify consideration along with alternative methods for major reconstructions of the upper limb.     

Changing concepts in the treatment of scaphoid nonunion: vascularized bone graft based on the 1,2 intercompartmental supraretinacular artery

Scaphoid fractures are a common injury encountered by hand surgeons. Fracture union can generally be achieved with cast immobilization or open reduction and internal fixation. Occasionally, these fractures fail to heal despite proper treatment or a nonunion may result from an unrecognized fracture. Traditionally, scaphoid nonunions have been treated with autologous bone grafts from the iliac crest; however, if the proximal pole is poorly vascularized, union may be difficult to achieved. Vascularized bone grafts are an alternate technique for difficult scaphoid nonunions, particularly those with avascular necrosis of the proximal segment. A graft from the distal radius based on the 1,2-intercompartmental supraretinacular artery is an excellent option for scaphoid nonunions. This article describes the anatomy of the 1,2-ICSRA and the surgical technique of harvesting a graft based on this pedicle. Vascularized bone grafts represent a changing concept in the treatment of scaphoid nonunions and provide a powerful tool for a difficult problem. The indications for this procedure continue to increase.     

Free medial femoral condyle bone grafting for scaphoid nonunions with humpback deformity and proximal pole avascular necrosis

Treatment of scaphoid nonunions remains a challenging problem, especially in the setting of proximal pole avascular necrosis or humpback deformity. Conventional bone grafting techniques have demonstrated unpredictable results in the setting of collapse deformities, whereas pedicled dorsal distal radius vascularized bone grafts have recently been reported to have nearly a 50% failure rate when used in scaphoid nonunions with proximal pole nonunion. Free vascularized medial femoral condyle bone grafting is one option for the treatment of scaphoid nonunions with proximal pole avascular necrosis associated with a humpback deformity. The indications, contraindications, and technique of free vascularized medial femoral condyle bone grafting are presented for the treatment of scaphoid nonunions associated with proximal pole avascular necrosis and humpback deformities.     

Nonunion: general principles and experimental data

Nonunions of long bone fractures can be treated successfully with one operative procedure in more than 90% of patients. In fact, 80% of patients can have good to excellent final restoration of mechanical axis alignment and proper length. Patients with infected nonunions may require more than one procedure to eliminate infection and heal the nonunion. Treatment must be tailored to the individual patient to address all components of the problem. We reviewed the main experimental data regarding the knowledge of nonunions and the basic methods that may be applied to the treatment of nonunions.     

Scaphoid reconstruction with vascularized bone grafts from the distal radius

The aim of the present technical report is to describe the alternative solutions for the reconstruction of scaphoid nonunions with pedicled vascularized bone grafts from the distal radius. The surgical technique for the reconstruction A. of proximal scaphoid nonunions with pedicled bone grafts (based on the 1,2 or on the 2,3 intercomparmtental arteries) or with capsular bone grafts from the dorsal distal radius and B. of waist nonunions of the scaphoid with grafts from the palmar distal radius, pedicled on the palmar carpal arch, is presented. Vascularized bone grafts from the adjacent radius are used for the treatment of scaphoid nonunions to enhance union and to revascularize a nonviable proximal pole. The most suitable graft is selected according to the location of the nonunion (at the waist or the proximal pole of the scaphoid) and to the previous procedures/scars at the wrist level.     

Osteogenic protein-1 (bone morphogenic protein-7) combined with various adjuncts in the treatment of humeral diaphyseal nonunions

A prospective study was conducted to determine the efficacy of using recombinant BMP-7 (rhOP-1) as an adjuvant in the treatment of diaphyseal humeral nonunions. Twenty-three consecutive patients with atrophic humeral diaphyseal nonunions were treated at seven separate institutions. All nonunions were fixed with either a compression plate or an intramedullary nail in conjunction with various bone grafting techniques. Recombinant OP-1 was delivered to the fracture site in a Type I collagen carrier at the time of fixation. All fractures went on to eventual union. There were no serious complications and no adverse reactions to the rhOP-I implant. Our study suggests that rhOP-1 may be a safe and effective adjuvant for the treatment of humeral diaphyseal nonunions.     

Management of proximal humeral nonunions and malunions

Surgical treatment of proximal humeral nonunions and malunions are technically challenging. Osteosynthesis with bone grafting for the treatment of nonunions is indicated in young, active patients with adequate bone stock in the proximal fragment and preservation of the glenohumeral articular surfaces. Corrective osteotomy may be a reasonable option for proximal humeral malunions in young patients without evidence of degenerative joint disease. Arthroplasty for proximal humerus nonunions and malunions has a guarded outcome because of limitations in shoulder motion, but pain relief is more consistently improved upon.