Bone transport for postinfectious segmental tibial bone defects with a combined ilizarov/taylor spatial frame technique

Treatment of large calvarial defects with bone transport osteogenesis: a preclinical sheep model

BACKGROUND

Bone transport osteogenesis (BTO), distraction of a free portion of bone across a defect, offers an autologous solution to large cranial defects that may allow treatment without permanent hardware implantation. This study establishes a sheep model to evaluate the feasibility and distraction kinetics of BTO.

METHODS

Subtotal cranial defects (3.5 × 3.5 cm) were created in 10 young adult sheep and a transport segment (3.5 × 2 cm) traversed the defect at varying distraction rates (0, 0.5, 1.0, and 1.5 mm/day) using semi-buried cranial distractors. After a 6-week consolidation period, sheep were euthanized and the resultant bone was analyzed by CT, histology, and mechanical testing.

RESULTS

Gross examination, histology, and 3D CT revealed that control animals had fibrous nonunion whereas distraction animals had ossified defects with fibrous nonunion at the distal docking site. There was one premature consolidation in the 0.5 mm/day group. The volume of bony regenerate in the 0.5, 1.0, and 1.5 mm/day distraction rate groups was statistically indistinct (P = 0.16). The mean flexural moduli (MPa) of non-decalcified samples from the control cranium, transport segment, and bone regenerate were found to be 4.50 ± 4.9, 6.17 ± 2.1, and 4.14 ± 4.8, respectively (P = 0.24).

CONCLUSIONS

This experiment provides proof of concept for BTO for large calvarial defects in a sheep model. Distraction at a rate of 0.5 mm per day may place individuals at higher risk for premature consolidation, but distraction rates did not have significant effects on regenerate quantity or quality. Future work will include the use of curvilinear distraction devices for 3-dimensional contour.

Infected nonunion of tibia and femur treated by bone transport

Objective

The objective of this study was to evaluate the effectiveness of the treatment of infected nonunion of tibia and femur by bone transport.

Material and methods

We retrospectively reviewed 110 patients with infected nonunion of tibia and femur treated by bone transport. Our study included 92 males and 18 females with a mean age of 38.90 years. The site of infected nonunion involved 72 tibias and 38 femurs. The mean length of the bone defects after radical debridement was 6.15 cm (range 3–13 cm).

Results

The mean follow-up after removal of the apparatus was 23.12 months (14–46 months). Ten patients including seven patients with infected tibia nonunion and three patients with infected femur nonunion were lost to follow-up. All the patients achieved bone union, and no recurrence of infection was observed. The time of bone transport took a mean of 67.50 days (range 33 to 137 days), and the mean external fixation index was 1.48 months/cm (range 1.15–1.71 months/cm). According to Association for the Study and Application of the Method of Ilizarov (ASAMI) classification, bone results were excellent in 68, good in 28, fair in 12, and poor in 2; functional results were excellent in 37, good in 42, fair in 21, and no poor.

Conclusions

Our study and the current evidence suggested that Ilizarov methods in the treatment of infected nonunion of tibia and femur acquired satisfied results. Radical debridement is the key step to control bone infection.

Ilizarov fixator combined with an intramedullary nail for tibial nonunions with bone loss: is it effective?

BACKGROUND

Treatment of tibial nonunion with bone loss is extremely difficult. A variety of techniques have been described, but each has shortcomings, in particular prolonged external fixation time as well as serious complications such as nonunion and infection. Accordingly, we developed a technique that seeks to reduce these complications by using a circular external fixator in addition to an intramedullary nail to achieve union, limb lengthening, and stability of the regenerated segment.

DESCRIPTION OF TECHNIQUE

First, the pseudoarthrosis area is resected, and acute compression is continued until bone contact at the docking site was achieved. Then primary grafting is applied to the docking site using a graft harvested from the patient's iliac bone, and the predrilled nail holes localized on the middle segment of the tibia are locked with a free-hand technique. Finally, lengthening is performed to overcome the leg-length discrepancy with an external fixator.

METHODS

Between 2008 and 2011, this technique was used to treat five patients with tibial nonunion with bone loss. All patients were available for a minimum of a 14-month followup (mean, 30 months; range, 14-58 months). General indications for the procedure were age older than 16 years, tibial nonunion with bone loss, and the absence of any psychiatric disorder. We evaluated external fixation time, external fixation index (defined as the duration of external fixation in months divided by the total amount of bone transported and/or the amount of lengthening in centimeters), and time to union on plain radiographs, clinical results using the Paley bone and functional assessment scores, and postoperative complications from chart review.

RESULTS

The external fixation time was 4 months (range, 3-5 months), and the average external fixation index was 0.4 months/cm. The mean time to bone union was 4.6 months (range, 3.5-5.5 months). All angles were determined to be in the normal range. No patients developed refracture or malalignment either on the docking site or the osteotomy site. Paley bone evaluation results were excellent in all five patients, and Paley functional results were excellent in four and good in one. We observed 10 pin-site infections as minor complications, and one patient was left with a residual equinus deformity of 5° as a major complication according to the Paley classification.

CONCLUSIONS

Our technique combining acute shortening and distraction osteogenesis had promising results for the treatment of tibial nonunion with bone loss in a small group of patients. However, future studies directly comparing available approaches to this difficult problem are required. Because this problem is uncommon, these studies will almost certainly require the cooperation of multiple large participating centers.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Bone transport for the treatment of infected forearm nonunion

OBJECTIVE

The objective of this study was to evaluate the effectiveness of the treatment of infected forearm nonunion by bone transport.

MATERIALS AND METHODS

We retrospectively reviewed 16 patients with infected forearm nonunion treated by bone transport. Our study included 10 males and 6 females with a mean of age 38.25 years. The site of bone defects involved 9 radius and 7 ulna. The average length of the bone defects after radical debridement was 3.81cm (range 2.2-7.5cm).

RESULTS

The mean follow-up after removal of the frame was 39.63 months (range 26-55 months). No patient was lost to follow-up. All the patients had bone union and no recurrence of infection was observed. The mean external fixation time was 6.19 months (range 3-10 months), and the mean external fixation index was 1.63 months/cm (range 1.14-2.00 months/cm). The mean degrees of wrist flexion were 49.69° (range 45-55°), and the mean degrees of wrist extension were 50.63° (range 40-60°). The mean degrees of elbow flexion were 143.12° (range 135-150°), and the mean degrees of elbow extension were 4.69° (range 0-20°). The mean degrees of forearm pronation were 82.50° (range 70-90°), and the mean degrees of forearm supination were 83.75° (range 75-90°).

CONCLUSION

Our study suggested that bone transport in the treatment of infected forearm nonunion acquired satisfied functional results. Radical debridement is the key step to control bone infection.

Strategies for managing bone defects of the lower extremity

Management of posttraumatic segmental bone loss as a result of severe open injuries of the lower extremity, high-energy closed injuries, and following failed initial treatment of complex fractures that develop pseudarthrosis continues to challenge reconstructive surgeons. There are numerous strategies for dealing with such injuries but the outcome is unpredictable. The procedure is rarely only one stage and complications frequently arise. In most cases the reconstruction process is long and difficult and amputation must be part of the decision-making process. All traditional treatment strategies have advantages and major drawbacks. To overcome some limitations, biologic treatments have been developed based on specific pathways of bone physiology and healing.

Distraction osteogenesis in the treatment of long bone defects of the lower limbs: effectiveness, complications and clinical results; a systematic review and meta-analysis

We carried out a systematic review of the literature to evaluate the evidence regarding the clinical results of the Ilizarov method in the treatment of long bone defects of the lower limbs. Only 37 reports (three non-randomised comparative studies, one prospective study and 33 case-series) met our inclusion criteria. Although several studies were unsatisfactory in terms of statistical heterogeneity, our analysis appears to show that the Ilizarov method of distraction osteogenesis significantly reduced the risk of deep infection in infected osseous lesions (risk ratio 0.14 (95% confidence interval (CI) 0.10 to 0.20), p < 0.001). However, there was a rate of re-fracture of 5% (95% CI 3 to 7), with a rate of neurovascular complications of 2.2% (95% CI 0.3 to 4) and an amputation rate of 2.9% (95% CI 1.4 to 4.4).The data was generally not statistically heterogeneous. Where tibial defects were > 8 cm, the risk of re-fracture increased (odds ratio 3.7 (95% CI 1.1 to 12.5), p = 0.036). The technique is demanding for patients, illustrated by the voluntary amputation rate of 1.6% (95% CI 0 to 3.1), which underlines the need for careful patient selection.

Evaluation of an endoscopic procedure for the treatment of docking site nonunion

OBJECTIVE

To determine the effectiveness of an endoscopic docking site surgery during the use of a classic bone transport technique for dealing with bone loss.

DESIGN

Retrospective comparative study.

SETTING

Level I trauma center.

PATIENTS

Nine patients treated with endoscopic docking site surgery (group 1) were compared with 18 patients treated with standard open grafting of the docking site (group 2). All 27 bone transports with distraction osteogenesis were performed for the treatment of segmental tibial bone defects.

INTERVENTION

In group 1, 6 tibial and 3 tibiotalar docking sites were endoscopically treated. Anteromedial (instrumentation) and anterolateral (visualization) portals were used without a tourniquet, using a 30-degree arthroscope and a motorized 5-mm shaver/abrader. Fibrous tissue was removed, bone ends abraded, and the bone canal cleaned with bone grafting.

MAIN OUTCOME MEASURE

Clinical and radiographic.

RESULTS

Bone transport lengthening was 9.7 and 9.1 cm in groups 1 and 2, respectively. Consolidation at the docking site occurred in 8 patients (89%) in group 1. The docking site consolidation time and index lengthening were lower in group 1 (18 vs. 20 weeks for group 2 and 1.59 vs. 1.82 mo/cm in group 1 vs. group 2). Time in the external fixator was similar between the 2 groups (461 vs. 466 days in group 1 vs. group 2). Normal alignment was observed in both groups.

CONCLUSIONS

This study provides evidence that minimally invasive endoscopic docking site treatment during bone transport is a safe and viable technique using a common arthroscopic instrumentation.

Taylor spatial frame fixation in patients with multiple traumatic injuries: study of 57 long-bone fractures

OBJECTIVE

To evaluate the Taylor spatial frame (TSF) for primary and definitive fixation of lower limb long-bone fractures in patients with multiple traumatic injuries.

DESIGN

Retrospective.

SETTING

Level I trauma center.

PATIENTS

Consecutive series of 52 patients, 57 fractures (25 femoral and 32 tibial), treated between 2005 and 2009. Forty-nine fractures (86%) were open. Injury Severity Score ≥16 for all patients.

INTERVENTION

Fifty-four fractures (95%) underwent definitive fixation with the TSF and 3 were treated primarily within 48 hours of injury. In 22 cases (39%), fractures were acutely reduced with the TSF, fixed to bone and the struts in sliding mode without further adjustment, and in 35 cases (61%), the total residual deformity correction program was undertaken.

MAIN OUTCOME MEASURE

Clinical and radiological.

RESULTS

Complete union was obtained in 52 fractures (91%) without additional surgery at an average of 29 weeks. Four nonunions and 1 delayed union occurred. Results based on Association for the Study and Application of the Method of Ilizarov criteria: 74% excellent, 16% good, 4% fair, and 7% poor for bone outcomes and 35% excellent, 47% good, and 18% fair for functional outcomes. Eighty-eight percent of patients returned to preinjury work activities.

CONCLUSIONS

Primary and definitive fixation with the TSF is effective. Advantages include continuity of device until union, reduced risk of infection, early mobilization, restoration of primary defect caused by bone loss, easy and accurate application, convertibility and versatility compared with a monolateral fixator, and improved union rate and range of motion for lower extremity long-bone fractures in patients with multiple traumatic injuries.

Clinical strategies at the docking site of distraction osteogenesis: are open procedures superior to the simple compression of Ilizarov?

This retrospective review reports on forty-five tibial non-unions who underwent docking site treatment for non-union using closed versus open and endoscopic strategies. In this cohort of patients, all but twelve were infected non-unions. Sixteen patients initially treated with single compression were compared to twenty-three patients treated with open revision of the docking site, and six endoscopic procedures. In the single compression group, an average of 6.4 cm of bone was resected and index lengthening was 2.01. In the open revision group, a mean of 9.4 cm was resected and the index lengthening was 1.72. In the endoscopic group, an average of 8.6 cm of bone was resected and index lengthening was 1.71. Consolidation at the docking site occurred in 41 cases out of 45 following the first procedure. There was no statistical difference between the three groups. Conclusive evidence of superiority of one modality of treatment over the other cannot be drawn from our data. The simple compression procedure requires less invasive surgery and is probably less demanding and more cost-effective in short transports, although the two cases of failure due to recurrence of sepsis were observed after this procedure. Further studies are desirable to investigate the effectiveness of open docking site grating procedures.

Long bone reconstruction using multilevel lengthening of bone defect fragments

PURPOSE

This paper presents experimental findings to substantiate the use of multilevel bone fragment lengthening for managing extensive long bone defects caused by diverse aetiologies and shows its clinical introduction which could provide a solution for the problem of reducing the total treatment time.

METHODS

Both experimental and clinical multilevel lengthening to bridge bone defect gaps was performed with the use of the Ilizarov method only.

RESULTS

The experimental findings and clinical outcomes showed that multilevel defect fragment lengthening could provide sufficient bone formation and reduction of the total osteosynthesis time in one stage as compared to traditional Ilizarov bone transport. The method of multilevel regeneration enabled management of critical-size defects that measured on average 13.5 ± 0.7 cm in 78 patients.

CONCLUSIONS

The experimental and clinical results proved the efficiency of the Ilizarov non-free multilevel bone plasty that can be recommended for practical use.

Clinical reliability of closed techniques and comparison with open strategies to achieve union at the docking site

PURPOSE

This retrospective review follows 31 tibial nonunions to compare union at the docking site using closed versus open strategies. In this cohort of patients, all but five were infected nonunions.

METHODS

Thirteen patients initially treated with single compression were compared with 18 patients treated by open revision of the docking site. In the single compression group, an average of 6.5 cm of bone was resected and index lengthening was 2.04. In the open revision group, a mean of 9.4 cm was resected and the index lengthening was 1.73.

RESULTS

Consolidation at the docking site occurred in all subjects in both groups. There was no statistical difference between the two groups. Conclusive evidence of superiority of one modality of treatment over the other cannot be drawn from our data.

CONCLUSIONS

The simple compression procedure requires less invasive surgery and is probably less demanding and more cost-effective in short transports.