Introduction and Objective

Management of gap non-union of the tibia, the major weight bearing bone of the leg remains controversial. The different internal fixation techniques are often weighed down by relatively high complication rates that include fractures which fail to heal (non-union). Minimally invasive techniques with ring fixators and bone transport (distraction osteogenesis) have come into picture as an alternative allowing alignment and stabilization, avoiding a graduated approach. This study was focused on fractures that result in a gap non-union of > 6 cm. Ilizarov technique was employed for management of such non-unions in this case series. The Ilizarov apparatus consists of rings, rods and kirschner wires that encloses the limb as a cylinder and uses kirschner wires to create tension allowing early weight bearing and stimulating bone growth. Ilizarov technique works on the principle of distraction osteogenesis, that is, pulling apart of bone to stimulate new bone growth. Usually, 4–5 rings are used in the setup depending on fracture site and pattern for stable fixation. In this study, we demonstrate effective bone transport and formation of gap non-union more than 6 cm in 10 patients using only 3 rings construct Ilizarov apparatus.

Abstract. OBJECTIVES. To determine if force measured using a strain gauge in circular external fixation frames is different for 1) different simulated stages of bone healing, and for 2) fractures clinically deemed either united or un-united. METHODS. In a laboratory study, 3 similar Ilizarov frame constructs were assembled using a Perspex bone analogue. Constructs were tested in 10 different clinical situations simulating different stages of bone healing including with the bone analogue intact, with 1,3 and 50mm gaps, and with 6 materials of varying stiffness's within the 50mm gap. A Bluetooth strain gauge was inserted across the simulated fracture focus, replacing one of the 4 threaded rods used to construct the frame. Constructs were loaded to 700N using an Instron testing machine and maximum force during loading was measured by the strain gauge. Testing was repeated with the strain gauge replacing each of the 4 threaded rods in turn, with measurements being repeated 3 times, across all 3 frame constructs for all 10 simulated clinical situations (n=360). Force measurements between the situations were compared using a Kruskal-Wallis test (KW) and a post-hoc Steel test was used for multiple comparison against control (intact bone model). Additionally, a pilot study has been initiated to assess clinical efficacy of the strain gauge measurement in patients with circular frames. The strain gauge replaced the anterior rod across the fracture focus for each patient. Patients were asked to step on a weighing scale with their affected limb, and maximum weight transfer through the limb and maximal force measured in the frame were recorded. This was repeated 3 times and a mean ratio of force to weight through affected limb was calculated for each patient. The clinical situation at each measurement was designated as united or un-united by one of the senior authors for analysis. Force measurements between the situations were compared using a Wilcoxon-Mann-Whitney test. RESULTS. In the laboratory study, including all constructs with the strain gauge in all positions, a statistically significant relationship between model stability and force measured was identified (KW test for overall relationship p<0.0001). The largest force was measured in the model with a 50mm gap (median 170N, IQR 155–192, range 83–213) and the smallest in the intact bone model (median 3N, IQR 1–8, range 0–11). Multiple comparison testing found a significant difference between intact bone and all the unstable situations (p=0.002 or better). Examining initial results from our pilot clinical study, nine measurements were available in seven patients. Three of these were taken in patients with fractures yet to unite, six in patients where union has since been confirmed clinically. The median force measured was significantly greater where the fracture was not united (median 1.66 N/kg, range 1.07–1.99 vs 0.12 N/kg, range 0.05–0.73, p=0.02). CONCLUSIONS. This laboratory study demonstrates that force measurement may be different at different stages of healing, and although only limited data was available, a pilot clinical study showed a significant relationship between the force measured and clinical union of the patient's fracture. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Background. Comminuted fractures involving the tibia are associated with a high level of complications including delayed healing and non-union, in conjunction with dramatically increased healthcare costs. Certain clinicians utilise a Pixel Value Ratio (PRV) of 1 to indicate such fracture healing. The subjectivity of this method has led to mixed outcomes including regenerate fracture. The poor prognosis of complex load bearing fractures is accentuated by the fact that no quantitative gold standard currently exists to which clinicians can reference regarding the definition of a healed fracture. The aim of the current study is to use patient specific finite element analysis of complex tibial fractures treated with Ilizarov frames to demonstrate callus maturation and to determine the optimum frame removal time. Methods. 3 patients (2 males, 1 female) were analysed following presentation with complex tibial fractures treated with Ilizarov frames. Patient specific computational analysis was performed according to radiographic data, incorporating maturing material properties to analyse the callus response to weight bearing over the healing timeframe. Computational results were compared to the PVR method to evaluate its efficacy in determining the optimum Ilizarov frame removal time. Results. All fractures were observed to clinically heal at a mean of 25.4 (±2.404) weeks. Following computational analysis however, the mean optimum Ilizarov frame removal time was seen to be 23.5 (±2.323) weeks. When compared with the PVR method, the suggested removal time presented a mean PVR of 1.025 (±0.017). Conclusion. Computational models of patient specific tibial fractures has shown promising correlations with the PVR method and has shown efficacy in predicting callus strength and subsequent optimum frame removal time. Level of Evidence. Level 4

Introduction. The BOAST (British Orthopaedic Association Standards for Trauma) guidelines do advise that open pilon fractures amongst other open lower limb fractures need to be treated at a specialist centre with Orthoplastic care. The purpose of this study was to determine clinical outcomes in patients with open pilon fractures treated as per BOAST guidelines including relatively aggressive bone debridement. Methods. A retrospective analysis of a single surgeon series of open pilon fractures treated between 2014 and 2019 was conducted. Injuries were graded according to the Gustillo-Anderson classification and all patients were included for the assessment of the rate of infection and fracture healing. Functional outcome assessment was performed in all patients according to the American Orthopedic Foot and Ankle Score (AOFAS) at 6 months after definitive surgery. Initial wound with bone debridement and application of a spanning external fixator was performed within an average of 13.5 (Range: 3–24) hours. Fixation with FWF (Fine Wire Frame) was performed when the wound was healed, with the mean time from primary surgery to application of FWF being 24.5 (Range: 7–60) days. Results. There was a total of 20 patients including 16 males and 4 females. The mean age was 50.45 (Range: 16–88) years. Follow-up was for an average of 23.2 (Range: 5–51) months. There were 3 patients with Gustilo Type I injuries, 6 with Type II, 4 Type with type IIIa and 7 with Type IIIb injuries. Average time to bone union was 9.3 (Range: 2–18) months. The mean AOFAS score was 66 (Range: 15–97) points. TSF was used on 18 patients, while 2 patients had an Ilizarov frame. A corticotomy was performed on 4 patients with critical bone defect post debridement, while 2 patients had Stimulan beads with antibiotics. There was 1 case (5%) of deep infection and 9 cases (45%) of superficial infection. There were also 2 cases (10%) of non-union which required bone grafting from their femur using a RIA (Reamer Irrigation Aspirator). Other complications included 1 case of acute compartment syndrome, 1 case of pulmonary embolism, 1 case of necrotic skin and 1 case of amputation. Conclusion. Results of our study suggests that the use of staged wound debridement including relatively aggressive bone debridement in conjunction with antibiotics, external fixators and patient tailored conversion from spanning external fixator to fine wire frame achieves low rates of wound infection and complications for patients with open pilon fractures

The implementation of knee arthrodesis has become synonymous with limb salvage in the presence of chronic sepsis and bone loss around the knee. This can be seen in failed trauma surgery or knee arthroplasty as an alternative to trans-femoral amputation. There is no prior literature assessing which factors affect knee arthrodesis using external fixation devices. Sixteen consecutive patients (four women and twelve men) made up of eleven infected knee implants, three internal fixations of the tibial following fractured tibial plateau as well as 2 infected native joints were identified. The mean age at initial surgery was 56 years (range 25 to 82 years). All procedures were performed under the direct supervision of the limb reconstruction teams using a standard protocol with either a Taylor spatial frame or Ilizarov frame. The patient records, microbiology results and radiographs of all patients who underwent knee arthrodesis at this institution between 1999 and 2010 were reviewed. Of the 16 patients in this study knee fusion occurred in eleven patients (69%). The five patients where arthrodesis failed all had significant bone loss on the pre-operative radiographs and confirmed at surgery. We found a relationship between a significant infection of the knee with MRSA and failure to fuse. Three of the five patients had MRSA isolated from inside the knee at some stage during their treatment. The five patients where fusion failed were on average older (mean age 63 years against 51 years) and had more extensive bone loss. Those who failed to fuse had more co-morbidities. We would conclude that where there is little or no bone loss, arthrodesis of the knee can be reliably achieved with the use of circular frame fixation. A greater number of negative factors also prolongs the amount of time spent in the external fixator. The presence of significant bone loss, infection, increased age and multiple co-morbidities requires careful evaluation and consideration of trans-femoral amputation as an alternative

Objectives

The purpose of this study was to compare the results and complications of tibial lengthening over an intramedullary nail with treatment using the traditional Ilizarov method.

The treatment of chronic osteomyelitis often includes surgical debridement and filling the resultant void with antibiotic-loaded polymethylmethacrylate cement, bone grafts or bone substitutes. Recently, the use of bioactive glass to treat bone defects in infections has been reported in a limited series of patients. However, no direct comparison between this biomaterial and antibiotic-loaded bone substitute has been performed.

In this retrospective study, we compared the safety and efficacy of surgical debridement and local application of the bioactive glass S53P4 in a series of 27 patients affected by chronic osteomyelitis of the long bones (Group A) with two other series, treated respectively with an antibiotic-loaded hydroxyapatite and calcium sulphate compound (Group B; n = 27) or a mixture of tricalcium phosphate and an antibiotic-loaded demineralised bone matrix (Group C; n = 22). Systemic antibiotics were also used in all groups.

After comparable periods of follow-up, the control of infection was similar in the three groups. In particular, 25 out of 27 (92.6%) patients of Group A, 24 out of 27 (88.9%) in Group B and 19 out of 22 (86.3%) in Group C showed no infection recurrence at means of 21.8 (12 to 36), 22.1 (12 to 36) and 21.5 (12 to 36) months follow-up, respectively, while Group A showed a reduced wound complication rate.

Our results show that patients treated with a bioactive glass without local antibiotics achieved similar eradication of infection and less drainage than those treated with two different antibiotic-loaded calcium-based bone substitutes.

Cite this article: Bone Joint J 2014; 96-B:845–50.