Autologous bone marrow grafting combined with demineralized bone matrix improves consolidation of docking site after distraction osteogenesis

Semi-focal bone transport versus traditional bone transport technique for the management of large tibial bone defects after trauma

How to deal with large tibial bone defects is still controversial. The purpose of this research was to compare the semi-focal bone transport (SFBT) technique with traditional bone transport (TBT) technique for treating such patients. Sixty-two patients were included and retrospectively analyzed. In all cases, after radical debridement large tibial bone defects remained. Patients were treated by the SFBT or TBT technique. The distraction, consolidation duration and complications were recorded by the patients' medical files. Based on the Association for the Study and Application of Methods of Ilizarov (ASAMI) standard, the bone and functional results were evaluated. The mean bone defect size was 7.7 ± 1.6 cm and 7.5 ± 2.1 cm for SFBT and TBT patients. The mean external fixation index (EFI) was 1.51 ± 0.14 months/cm and 1.89 ± 0.25 months/cm for SFBT and TBT patients (p < 0.05), respectively. With respect to bone and function results, there was no significant differences between the two groups (p > 0.05). The mean number of complications per patient was 1.1 ± 0.6 and 1.6 ± 0.7 for SFBT and TBT patients (p < 0.05). Compared to the traditional bone transport technique, patients using the semi-focal bone transport technique achieved better clinical effects, including shorter EFI and less complications. Therefore, the SFBT technique could be a new option for patients with large tibial bone defects.

Docking site interventions following bone transport using external fixation: a systematic review of the literature

PURPOSE

Although bone transport is a well-recognised technique to address segmental bone defects, optimal management of docking sites is not absolutely determined. Some surgeons routinely intervene in all cases, and others prefer to observe and intervene only if spontaneous union does not occur. Primary aim of the study was to compare rates of docking site union between patients who underwent routine docking site intervention and those who did not.

METHODS

A systematic literature review using the keywords "bone transport", "docking", "tibia", and "femur" was performed in PubMed using PRISMA guidelines. Studies published in English from January 2000 to August 2022 were included and assessed independently by two reviewers. Pooled analysis was undertaken dividing patients into two groups: those managed by routine intervention and those initially observed.

RESULTS

Twenty-three clinical studies met the eligibility criteria for pooled analysis, including 1153 patients, 407 in the routine intervention and 746 in the observed group. The rate of union after initial treatment was 90% in the routine intervention group and 66% in the observed group (p < 0.0001). Overall union rates at the end of treatment were similar at 99% in both groups. Patients in the observed group required an average of 2.2 procedures to achieve union overall compared with 3.8 in the routine intervention group. Time in frame was similar between groups.

CONCLUSION

Based on the current literature, routine docking site interventions cannot be recommended, since this may lead to unnecessary interventions in two thirds of patients. Timely selective intervention in those at high risk or after a defined period of observation would appear to be a logical approach.

Debridement-Reconstruction-Docking Management System Versus Ilizarov Technique for Lower-Extremity Osteomyelitis

BACKGROUND

Osteomyelitis causes marked disability and is one of the most challenging diseases for orthopaedists to treat because of the considerable rate of infection recurrence. In this study, we proposed and assessed the debridement-reconstruction-docking (DRD) system for the treatment of lower-extremity osteomyelitis. This procedure comprises 3 surgical stages and 2 preoperative assessments; namely, pre-debridement assessment, debridement, pre-reconstruction assessment, reconstruction, and docking-site management. We evaluated the use of the DRD system compared with the Ilizarov technique, which is defined as a 1-stage debridement, osteotomy, and bone transport.

METHODS

This retrospective cohort included 289 patients who underwent either DRD or the Ilizarov technique for the treatment of lower-extremity osteomyelitis at a single institution between January 2013 and February 2021 and who met the eligibility criteria. The primary outcome was the rate of infection recurrence. Secondary outcomes included the external fixator index (EFI), refracture rate, and the Paley classification for osseous and functional results. An inverse-probability-weighted regression adjustment model was utilized to estimate the effect of the DRD system and Ilizarov technique on the treatment of lower-extremity osteomyelitis.

RESULTS

A total of 131 and 158 patients underwent DRD or the Ilizarov technique, respectively. The inverse-probability-weighted regression adjustment model suggested that DRD was associated with a significant reduction in infection recurrence (risk ratio [RR], 0.26; 95% confidence interval [CI], 0.13 to 0.50; p < 0.001) and EFI (-6.9 days/cm, 95% CI; -8.3 to -5.5; p < 0.001). Patients in the DRD group had better Paley functional results than those in the Ilizarov group (ridit score, 0.55 versus 0.45; p < 0.001). There was no significant difference between the 2 groups in the rate of refracture (RR, 0.87; 95% CI, 0.42 to 1.79; p = 0.71) and Paley osseous results (ridit score, 0.51 versus 0.49; p = 0.39).

CONCLUSIONS

In this balanced retrospective cohort of patients with lower-extremity osteomyelitis, the use of the DRD system was associated with a reduced rate of infection recurrence, a lower EFI, and better Paley functional results compared with the use of the Ilizarov technique.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Use of locked plates and mono-rail fixator in segmental tibial defects: A prospective interventional study

Introduction

The management of gap non-union is a major challenge to both the clinician and the patient as it is technically difficult, time-intensive, and physically arduous for the patient along with an unpredictable result. Gap non-union can arise from extrusion of bony fragment at the time of trauma or after debridement of unhealthy bone later. Moreover, Tibia because of its subcutaneous anatomy can easily undergo bone-loss and segmental defect. Among various methods available for managing gap non-union of tibia distraction osteogenesis using either ilizarov fixator or mono-rail fixator is the most popular one. Here we present functional and bony outcomes of combined use of locking plate and Limb Reconstruction System (LRS) in tibial gap non-union and assess whether it decreases fixator time and related complications.

Patients and methods

A prospective intervention study constituting 10 patients with Paley's type B1 tibial gap non-union over a period of 22months. In first stage, debridement was done; tibial locking plate and mono-rail fixator were applied along with corticomy at proximal tibia. Distraction was started 7-14 days later. At the end of distraction phase, fixator was removed and transported segment was fixed with screws with or without bone grafting at docking site. Patients were followed up every 6 weeks for radiological and clinical assessment. Functional assessment using Application for the Study and Application of the Method of Ilizarov (ASAMI) functional score, and Musculoskeletal Tumour Society (MSTS) functional score while bone outcome was assessed with ASAMI bone score. Quality of regenerate was assessed by Fernandez-Esteve grading. Detailed scoring was done at the time of index surgery, at the time of LRS removal and at the time of consolidation phase.

Results

All the 10 patients were male with mean age of 33 years. The mean defect size was 4.94 cm after debridement. Minimum duration of follow up was 30 weeks after removal of LRS. Mean duration between trauma and inclusion in the study was 17.7 months. The median external fixator index was 15.63 days/cm. The complication rate was 1.3/patient. According to Paley's classification, there were eleven problems and two obstacles, and no true complications. Both ASAMI bone score and functional scores were excellent in three and good in six patients. The median MSTS composite score was 76.66%.

Conclusion

The integrated fixation is an effective and satisfactory method enabling early external fixator removal with low rate of complication. So, this technique can be recommended for the management of segmental tibial defects.

Level of evidence

II.

An osteoinductive and biodegradable intramedullary implant accelerates bone healing and mitigates complications of bone transport in male rats

Bone transport is a surgery-driven procedure for the treatment of large bone defects. However, challenging complications include prolonged consolidation, docking site nonunion and pin tract infection. Here, we develop an osteoinductive and biodegradable intramedullary implant by a hybrid tissue engineering construct technique to enable sustained delivery of bone morphogenetic protein-2 as an adjunctive therapy. In a male rat bone transport model, the eluting bone morphogenetic protein-2 from the implants accelerates bone formation and remodeling, leading to early bony fusion as shown by imaging, mechanical testing, histological analysis, and microarray assays. Moreover, no pin tract infection but tight osseointegration are observed. In contrast, conventional treatments show higher proportion of docking site nonunion and pin tract infection. The findings of this study demonstrate that the novel intramedullary implant holds great promise for advancing bone transport techniques by promoting bone regeneration and reducing complications in the treatment of bone defects.

Predictive factors for docking site procedure in bone transport for large lower extremity segmental defects

BACKGROUND

Segmental bone transport is a common technique for treating large segmental bone defects. However, a docking site procedure is often necessary in segmental bone transport. To date, no prognostic factors for the need of docking site procedure have been reported. Thus, the decision is often made at random, based on the surgeon's subjective judgment and experience. The aim of this study was to identify prognostic factors for the need of docking site operation.

METHODS

Patients with segmental bone transport in lower extremity bone defects were included regardless of age, aetiology, and defect size. We excluded patients undergoing treatments that were not yet completed, and those who discontinued therapy by any reason. The need for docking site operation was modelled with logistical and linear regression as well as univariate analysis of variances (ANOVA). Receiver operating characteristics (ROC) curve analysis was also performed.

RESULTS

Twenty-seven patients from age 12 to 74 years (mean age: 39.07 ± 18.20 years) were included. The mean defect size was 76.39 ± 41.10 mm. The duration of transport (days) showed a significant influence (p = 0.049, 95%CI: 1.00-1.02) on the need for docking site operation. No other significant influences were detected.

CONCLUSION

A link between the duration of transport and the need for docking site operation was detected. Our data showed that if a threshold of about 188 days is exceeded, docking surgery should be considered.

Comparison of antibiotic-impregnated bone cement coverage versus vacuum sealing drainage in semi-open bone grafting using for tibial fracture with infected bone and soft tissue defect: a retrospective analysis

OBJECTIVE

To compare antibiotic-impregnated bone cement coverage (bone cement surface technique; BCS-T) versus vacuum sealing drainage (VSD) for tibial fracture with infected bone and soft tissue defect.

METHOD

This retrospective analysis compared the clinical outcomes in patients undergoing BCS-T (n = 16) versus VSD (n = 15) for tibial fracture with infected bone and soft tissue defect at the Third Hospital of Hebei Medical University from March 2014 to August 2019. For BCS-T group, osseous cavity was filled with autograft bone graft after debridement, and then the wound was covered with a 3-mm layer of bone cement impregnated with vancomycin and gentamycin. The dressing was changed every day in the first week, and every 2 ~ 3 days in the second week. For VSD group, a negative pressure of -150 ~ -350 mmHg was maintained, and the dressing was changed every 5-7 days. All patients received antibiotics treatment based on bacterial culture results for 2 weeks.

RESULTS

The 2 groups did not differ in age, sex and key baseline characteristics, including type of Gustilo-Anderson classification, size of the bone and soft tissue defect, the percentage of primary debridement, bone transport, and the time from injury to bone grafting. The median follow-up was 18.9 months (range:12-40). The time to complete coverage of bone graft by granulation tissue was 21.2 (15.0-44.0) and 20.3 (15.0-24.0) days in the BCS-T and VSD groups, respectively (p = 0.412). The 2 groups also did not differ in wound healing time (3.3 (1.5-5.5) versus 3.2(1.5-6.5) months; p = 0.229) and bone defect healing time (5.4(3.0-9.6) versus 5.9(3.2-11.5) months; p = 0.402). However, the cost of covering material was significantly reduced in the BCS-T group (2071 ± 134 versus 5542 ± 905 yuan; p = 0.026). Paley functional classification at 12 months did not differ between the 2 groups (excellent in 87.5% versus 93.3% in the 2 groups; p = 0.306).

CONCLUSION

BCS-T could achieve clinical outcomes similar to VSD in patients receiving bone graft for tibial fracture with infected bone and soft tissue defect, but material cost was significantly reduced. Randomized controlled trials are needed to verify our finding.

Allografts: expanding the surgeon's armamentarium

In Germany, bone allografts are widely used and their application in clinics has increased over the years. Successful use of allografts depends on many factors such as the procurement, processing, sterilization and the surgeon's surgical experience. Tissue banks have provided safe and sterile allografts for decades ranging from hard to soft tissue. Allografts are obtained from various tissues such as bone, tendon, amniotic membrane, meniscus and skin. An advantage of allografts is their wide applicability that has never been limited by indication restrictions thus providing a huge benefit for surgeon's. The use of the correct allograft in different indications is extremely important. Thereby surgeons have access to various allograft forms such as mineralized, demineralized, freeze-dried, paste, powder, chips strips and putty. The vast options of allografts allow surgeon's to use allografts in indications they deem fit. Currently, the application of allografts is at the discretion of the expert surgeon. However, regulations are often changed locally or internationally and may impact/limit allograft use to certain indications. Here, we report the different indications where our peracetic acid (PAA) sterilised bone allografts were used as well as general literature on bone allograft use in other indications.

Acute shortening and re-lengthening versus antibiotic calcium sulfate-loaded bone transport for the management of large segmental tibial defects after trauma

Background

The purpose of this paper was to compare the clinical effects of acute shortening and re-lengthening (ASR) technique with antibiotic calcium sulfate-loaded bone transport (ACSBT) technique for the management of large segmental tibial defects after trauma.

Methods

In this retrospective study, 68 patients with large segmental tibial defects were included and completely followed. The bone loss was 3–10 cm. ASR group included 32 patients, while ACSBT group contained 36. There was no significant difference in demographic information between the two groups. The external fixation time (EFT) and external fixation index (EFI) were compared. Bone defect healing and limb functions were evaluated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. Complications were compared by Paley classification.

Results

The mean EFT was 9.2 ± 1.8 months in ASR group and 10.1 ± 2.0 months in ACSBT group, respectively. The mean EFI was 1.5 ± 0.2 month/cm and 1.4 ± 0.3 month/cm. According to the ASAMI criteria, in ASR group bone defect healing was excellent in 22 cases, good in 7 cases and fair in 3 cases. In ACSBT group, it was excellent in 23 cases, good in 11 cases and fair in 2 cases. In ASR group, the limb function was excellent in 15 cases, good in 7 cases and fair in 10 cases, while it was excellent in 14 cases, good in 9 cases and fair in 13 cases with ACSBT group. There was no significant difference in EFI, bone defect healing and limb functions between the two groups (p > 0.05). The mean number of complications per patient in ACSBT group was significantly lower than that in ASR group (p < 0.05).

Conclusion

Both techniques can be successfully used for the management of large segmental tibial defects after trauma. There was no significant difference in EFI, limb functions and bone defect healing between the two groups. Compared with ASR group, the complication incidence in ACSBT group was lower, especially the infection-related complications. Therefore, for patients with large segmental bone defects caused by infection or osteomyelitis, ACSBT technique could be the first choice.

Analysis of bone transport for ankle arthrodesis as a limb salvage procedure for the treatment of septic pilon fracture nonunion

Septic nonunion of the pilon region with ankle joint infection is challenging for orthopedic surgeons to treat and is associated with a high risk of limb loss. Therefore, the aim of this study was to evaluate the effectiveness of bone transport for ankle arthrodesis in salvaging the limp after septic ankle destruction of the pilon region. We conducted a single-center, retrospective study including 21 patients treated for septic pilon nonunion with accompanying septic ankle destruction via Ilizarov bone transport between 2004 and 2018. In all cases, the complete excision of the nonunion and the resection of the ankle joint were carried out, followed by treating the bone and joint defect with a bone transport into the ankle arthrodesis. In 12/21 patients an additional flap transfer was required due to an accompanying soft tissue lesion. The overall healing and failure rate, final alignment and complications were recorded by the patients’ medical files. The bone-related and functional results were evaluated according to the Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system and a modified American Orthopedic Foot and Ankle Society (AOFAS) scale. After a mean follow-up of 30.9 ± 15.7 months (range 12–63 months), complete bone and soft tissue healing occurred in 18/21 patients (85.7%). The patients had excellent (5), good (7), fair (4), and poor (3) results based on the ASAMI functional score. Regarding bone stock, 6 patients had excellent, 7 good, and 6 fair results. The modified AOFAS score reached 60.6 ± 18 points (range, 29–86). In total, 33 minor complications and 28 major complications occurred during the study period. In 2 cases, a proximal lower leg amputation was performed due to a persistent infection and free flap necrosis with a large soft tissue defect, whereas in one case, persistent nonunion on the docking side was treated with a carbon orthosis because the patient refused to undergo an additional surgery. Bone transport for ankle arthrodesis offers the possibility of limb salvage after septic ankle destruction of the pilon region, with acceptable bony and functional results. However, a high number of complications and surgical revisions are associated with the treatment of this severe complication after pilon fracture.

Biologic Reconstruction With a Motorized Intramedullary Bone Transport Nail After Tumor Resection

Distraction osteogenesis is an option for reconstruction of intercalary defects. The use of bone transport after tumor surgery has been limited because of concerns of pin tract infections with external fixation and the theoretical risk of causing tumor growth. The effects of chemotherapy and radiation on the regenerate and healing of the docking site are also not well studied, but the current literature has mostly favorable outcomes with no evidence of causing tumor proliferation. The Precice bone transport nail offers a noninvasive method of distraction osteogenesis, which eliminates the need for prolonged external fixation and the risk of pin tract infections. This report discusses the technique for using the Precice bone transport nail after tumor resection. Bone transport may be considered for intercalary defects after en bloc resection of sarcoma, metastatic disease, and benign aggressive bone tumors. The use of distraction osteogenesis after tumor resection is a promising technique for the biologic reconstruction of intercalary defects.

Antibiotic calcium sulfate-loaded hybrid transport versus traditional Ilizarov bone transport in the treatment of large tibial defects after trauma

Background

The purpose of this study was to compare the clinical effects of antibiotic calcium sulfate-loaded hybrid transport (ACSLHT) and traditional Ilizarov bone transport (TIBT) in the treatment of large tibial defects after trauma.

Methods

Eighty-five patients with large tibial defects after trauma were selected for retrospective study. The range of tibial defects was 6–22 cm. After thorough debridement and infection controlled, bone transport technique was used to reconstruct tibial defects. Forty-four patients were treated with ACSLHT technique (the ACSLHT group), while the other 41 were treated with TIBT technique (the TIBT group). Time in external fixator was evaluated by EFI score. Enneking score was used to evaluate limb functions. SAS score was used to evaluate postoperative anxiety status. In addition, complication incidence was compared, including axis deviation, docking site nonunion, infection recurrence and so on.

Results

There was no significant difference in preoperative general data between ACSLHT and TIBT group. EFI score in ACSLHT and TIBT group was 0.6 ± 0.1 cm/month and 1.7 ± 0.3 cm/month, respectively (P < 0.05). Enneking score of ACSLHT and TIBT group was 86.5% and 75.1% (P < 0.05). SAS score of ACSLHT group was significantly lower than that of TIBT group (P < 0.05). Complication incidence in ACSLHT group was significantly lower than that in TIBT group (P < 0.05).

Conclusions

Compared with TIBT group, ACSLHT group had shorter time in external fixator, better limb functions, lower postoperative anxiety score and lower complication incidence which is worth of clinical promotion.

Topical Review: Bone Marrow Aspirate Concentrate and Its Clinical Use in Foot and Ankle Surgery

Bone marrow aspirate concentrate (BMAC) is now commonly used in orthopedic surgery. Animal studies showed promising results for cartilage, bone, and soft tissue healing; however, many of these outcomes have yet to be translated to human models. While there has been an increase in the use of BMAC in foot and ankle procedures, the associated clinical evidence is limited. The purpose of this review is to analyze the existing literature in order to evaluate the safety and efficacy of BMAC in foot and ankle surgery.

Can bone marrow aspirate improve mandibular fracture repair in camels (Camelus dromedarius)? A preliminary study

Background

Mandibular fractures are common in camels, leading to considerable economic losses. This study explored methods of improving mandibular fractures repair, adjuvant with interdental wire, or bone plate fixation. Autologous bone marrow (BM) injection enhances osteogenesis and rapid healing.

Objectives

To investigate the effect of autologous BM aspirate as an adjuvant treatment for repairing mandibular fractures in camels with interdental wire, or bone plate fixation.

Methods

Thirty dromedary camels aged 5–8 years and of both sexes were randomly divided into 4 treatment groups: group 1 (n = 10) treated with stainless steel wire fixation and BM injection at the fracture line, group 2 (n = 10) treated with plate fixation and BM injection at the fracture line, group 3 (n = 5) treated with stainless steel bone wire fixation and placebo saline injection at the fracture line, and group 4 (n = 5) treated with plate fixation and placebo injection at the fracture line. The mandibular fractures were followed weekly for 12 weeks postoperatively to assess improvement and healing based on clinical evaluation, radiographic union scale, and bone turnover markers (i.e., bone alkaline phosphatase, osteocalcin, pyridinoline, and deoxypyridinoline).

Results

Compared to other groups, elevated bone turnover markers in group 1 were demonstrated (p < 0.05) on the seventh postoperative day. Likewise, compared to other groups, both clinical findings and radiographic union scale significantly improved (p < 0.05) in group 1 on the 56th postoperative day.

Conclusions

BM aspirate has a promising beneficial osteogenic effect on mandibular fracture repair in camels, most notably when combined with interdental wire fixation.

Ilizarov bone transport using an intramedullary cable transportation system in the treatment of tibial bone defects

INTRODUCTION

Segmental tibia defects remain challenging for orthopedic surgeons to treat. The aim of this study was to demonstrate bone-related and functional outcomes after treatment of complex tibial bone defects using Ilizarov bone transport with a modified intramedullary cable transportation system (CTS).

PATIENTS AND METHODS

We conducted a single-center, retrospective study including all 42 patients treated for tibial bone loss via Ilizarov bone transport with CTS between 2005 and 2018. Bone-related and functional results were evaluated according to the Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system. Complication and failure rates were determined by the patients' medical files.

RESULTS

Patients had a mean age of 45.5 ± 15.1 years. The mean bone defect size was 7.7 ± 3.4 cm, the average nonunion scoring system (NUSS) score was 59 ± 9.5 points, and the mean follow-up was 40.8 ± 24.4 months (range, 13-139 months). Complete bone and soft tissue healing occurred in 32/42 patients (76.2%). These patients had excellent (10), good (17), fair (2), and poor (3) results based on the ASAMI functional score. Regarding bone stock, 19 patients had excellent, 10 good, and 3 fair results. In total, 37 minor complications and 62 major complications occurred during the study. In 7 patients, bone and soft tissue healing occurred after CTS failure with either an induced membrane technique or classic bone transport; 3 patients underwent lower leg amputation. Patients with treatment failure were significantly older (57.6 vs. 41.8 years; p = 0.003). Charlson score and treatment failure had a positive correlation (Spearman's rho 0.43; p = 0.004).

CONCLUSION

Bone transport using both intramedullary CTS and Ilizarov ring fixation is viable for treating patients with bone loss of the tibia and complex infection or soft tissue conditions. However, a high number of complications and surgical revisions are associated with the treatment of this severe clinical entity and should be taken into account.

Role of Primary Autologous Bone Graft at Docking Site in the Treatment of Infected Non-union Tibia Using Rail Fixation System

Introduction:

Distraction osteogenesis has been used effectively in the management of tibia non-unions with skeletal defect. A retrospective case series study of the infected non-union tibia managed with acute docking in a rail fixation system was conducted at a tertiary care hospital in South India. It was designed to evaluate the use of autologous bone graft at the docking site in achieving an early union with a seven years follow-up period.

Materials and Methods:

From 2010 to 2017, a total of 19 patients with infected tibia non-union and a bone defect less than 3cm, were treated with debridement and a monolateral frame fixation with acute shortening and lengthening. The patients were divided into two groups: one in which no bone graft was used at the docking site during early years of the study; and a later group in which autologous bone graft was used at the acute docking site primarily in addition to compression. Consolidation at the docking site was assessed both radiographically and clinically, and the results were statistically analysed.

Results:

There were 12 patients in Group I without bone graft, where consolidation at the docking site was noted after a mean duration of 22.08 ± 3.87 weeks. There were seven patients in Group II with bone graft, where the mean time for docking site consolidation was significantly lower at 16.57 ± 3.82 weeks. No docking site complications were noted in either group.

Conclusion:

Primary autologous bone graft enhances docking site consolidation in acute shortening. The routine use of bone graft at the docking site in acute shortening will expedite the docking site union with reduction of treatment time.

Infected bone defects in the lower limb. Management by means of a two-stage distraction osteogenesis protocol

INTRODUCTION

Although bone transport is generally accepted as the gold standard for the treatment of segmental septic bone defects, some aspects of its practical application are still open to debate. We present our results in this field and compare them with the series published so far.

MATERIAL AND METHODS

We reviewed all our patients (2010-2018) that underwent a bone transport procedure in the lower limb due to a septic bone defect. We calculated the bone healing index (BHI), the external fixation index (EFI), the rate of complications and the clinical results. We statistically compared our results with 63 publications with a similar scope.

RESULTS

Thirty-five patients (30 M/5F) with a mean age of 40 years and a mean follow-up of 45 months were included. Bone segment was 24 T/11F and mean defect was 8.4 cm (7.34 T/ 10.73F). Mean global BHI was 45.62 days/cm (48.16 T/40.09F). Mean EFI was 2.37 months/cm. Results were excellent in 9 patients, good in 23 and bad in 3. Bone graft was used in 60% of the cases.

DISCUSSION

The size of our series is similar to previously published ones, although the mean age of our patients is higher and they present a larger bone defect. BHI of our series is similar to that of other series, although EFI is significantly higher. The number of complications is also in line with the existing literature.

CONCLUSION

The use of a two-stage technique for managing segmental bone defects of septic origin in the lower extremity is a valid alternative. Our series shows results comparable to the current literature.

Treatment of Tibial and Femoral Bone Defects With Bone Transport Over an Intramedullary Nail

OBJECTIVES

To evaluate the results of the bone transport over an intramedullary nail (BTON) technique for the treatment of segmental bone defects.

DESIGN

Retrospective review of case series.

SETTING

Level 1 trauma center.

PATIENTS/PARTICIPANTS

We included 40 patients who underwent reconstruction of the lower limb with BTON technique between 2000 and 2018. The technique was performed in the tibial segments in 21 patients and in the femoral segments in 19 patients.

INTERVENTION

The surgical technique was performed in 2 stages for patients with infected nonunion. Infection was eradicated in all patients at the first stage. For the BTON at the second stage, monolateral external fixators and circular external fixators were used for femoral and tibial defects, respectively. In cases of defects without any infection, debridement with a single-stage BTON was performed.

MAIN OUTCOME MEASUREMENTS

Complications as well as radiological and clinical results were evaluated according to the criteria of Paley-Maar.

RESULTS

Minor complications occurred in 11 patients: pin site problems (9), cellulitis (1), and skin detachment due to Schanz screw (1). Major complications occurred in 8 patients: docking site nonunion (4), early consolidation and Schanz screw failure (1), knee flexion contracture (1), and ankle equinus contracture (2). Four patients had osteomyelitis as residual sequelae. Bone score was excellent in 27 patients. Excellent functional results were obtained in 31 patients.

CONCLUSIONS

The BTON technique is associated with low cost because of the short treatment period, low complication risk, and rapid rehabilitation and is not limited by the amount of bone transport.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparison of Ilizarov Bifocal, Acute Shortening and Relengthening with Bone Transport in the Treatment of Infected, Segmental Defects of the Tibia

This prospective study compared bifocal acute shortening and relengthening (ASR) with bone transport (BT) in a consecutive series of complex tibial infected non-unions and osteomyelitis, for the reconstruction of segmental defects created at the surgical resection of the infection. Patients with an infected tibial segmental defect (>2 cm) were eligible for inclusion. Patients were allocated to ASR or BT, using a standardized protocol, depending on defect size, the condition of soft tissues and the state of the fibula (intact or divided). We recorded the Weber-Cech classification, previous operations, external fixation time, external fixation index (EFI), follow-up duration, time to union, ASAMI bone and functional scores and complications. A total of 47 patients (ASR: 20 patients, BT: 27 patients) with a median follow-up of 37.9 months (range 16-128) were included. In the ASR group, the mean bone defect size measured 4.0 cm, and the mean frame time was 8.8 months. In the BT group, the mean bone defect size measured 5.9cm, and the mean frame time was 10.3 months. There was no statistically significant difference in the EFI between ASR and BT (2.0 and 1.8 months/cm, respectively) (p = 0.223). A total of 3/20 patients of the ASR and 15/27 of the BT group needed further unplanned surgery during Ilizarov treatment (p = 0.006). Docking site surgery was significantly more frequent in BT; 66.7%, versus ASL; 5.0% (p < 0.0001). The infection eradication rate was 100% in both groups at final follow-up. Final ASAMI functional rating scores and bone scores were similar in both groups. Segmental resection with the Ilizarov method is effective and safe for reconstruction of infected tibial defects, allowing the eradication of infection and high union rates. However, BT demonstrated a higher rate of unplanned surgeries, especially docking site revisions. Acute shortening and relengthening does not reduce the fixator index. Both techniques deliver good functional outcome after completion of treatment.

Comparison of the use of antibiotic-loaded calcium sulphate and wound irrigation-suction in the treatment of lower limb chronic osteomyelitis

AIMS

We sought to compare the efficacy of antibiotic-loaded calcium sulphate with wound irrigation-suction in patients with lower limb chronic osteomyelitis.

PATIENTS AND METHODS

Adult patients with lower limb chronic osteomyelitis treated at our hospital by means of segmental bone resection, antibiotic-loaded calcium sulphate implantation or wound irrigation-suction, followed by bone transport with external fixator from January 2011 to July 2015 were retrospectively evaluated. The clinical presentation, laboratory results, complications, docking obstruction, infection recurrence were compared.

RESULTS

There were totally 74 patients met the inclusion criteria. Docking obstruction rate and infection recurrence were higher in the irrigation group with significant difference. The success rate of the first operation was 90.74% in the calcium sulphate group compared with 45% in the irrigation group. Postoperaton leakage of the incision happened more in the calcium sulphate group, but it wasn't a risk factor for docking obstruction and infection recurrence. Patients in the calcium sulphate group had shorter hospital stay and systemic antibiotic treatment, also with less external fixator index.

CONCLUSIONS

The findings of our study suggest that antibiotic-loaded calcium sulphate implantation for lower chronic limb osteomyelitis was a more successful method than wound irrigation-suction, it greatly decreased infection recurrence and docking obstruction. Postoperative leakage after implantation didn't worsen patient's outcome.

Bone stock reconstruction for huge bone loss using allograft-bones, bone marrow, and teriparatide in an infected total knee arthroplasty

Bone stock reconstruction using allograft-bones, bone marrow (BM), and teriparatide (TPTD) is reported. Huge and extensive bone losses occurred in the medullary cavity of the femur and tibia of a 55-year-old female rheumatoid arthritis patient with severe osteoporosis after debridement of her infected total knee arthroplasty. Because of the risks of unstable prosthetic fixation and intra-operation fracture, we first reconstructed the bone stock. Chipped allograft bones mixed with BM were implanted in the bone defects, and TPTD was administrated for the osteoporosis therapy. Good bone formation was found by computed tomography after 4 months. Bone turnover markers and bone mineral density (BMD) were increased at 6 months. We confirmed good bone formation at the re-implantation surgery. The newly formed bone harvested during the re-implantation surgery showed active osteoblast-like lining cells. TPTD is known to enhance allograft bone union, mesenchymal stem cell differentiation into osteoblasts, and BMD. This tissue engineering-based technique might be improved by the various effects of TPTD. This method without any laboratory cell culture might be a good option for bone stock reconstruction surgery in ordinary hospitals.

In vitro and in vivo evaluation of xenogeneic bone putty with the carrier of hydrogel derived from demineralized bone matrix

The demineralized bone matrix (DBM) putty is a traditional bone graft utilized to facilitate the repair and reconstruction of bone. Recent studies indicated the DBM putties with the various carriers were different in bone repairing ability. In order to prepare a kind of DBM putty with a good biocompatibility and bioactivity, the DBM gel was processed from the DBM and the feasibility as a carrier for the DBM putty was evaluated. After the bovine DBM gel was prepared, the BMPs content as well as the ability to promote osteogenic differentiation of MC3T3-E1 cells in vitro were investigated. Then the DBM putty was prepared and filled into the rat calvarial defect model to evaluate the bone repairing ability by micro-CT and histology. The result showed there was 2.953 ± 0.054 ng BMP contained in per gram of the DBM gel. And the ALP production of MC3T3-E1 cells in the DBM gels group increased with prolonged culturing, the mineralized nodules formed in MC3T3-E1 cells on 14th day after co-culture. The putty prepared by DBM gel was easy to handle without loss of DBM particles at room temperature. In the rat calvarial bone defect experiment, histological observation showed more mature bone formed in the DBM putty group than that in the type I collagen group at 12 weeks, which indicated the bone putty prepared by DBM gel exhibited a better bone repair capability.

Applications of stem cells in orthodontics and dentofacial orthopedics: Current trends and future perspectives

A simple overview of daily orthodontic practice involves use of brackets, wires and elastomeric modules. However, investigating the underlying effect of orthodontic forces shows various molecular and cellular changes. Also, orthodontics is in close relation with dentofacial orthopedics which involves bone regeneration. In this review current and future applications of stem cells (SCs) in orthodontics and dentofacial orthopedics have been discussed. For craniofacial anomalies, SCs have been applied to regenerate hard tissue (such as treatment of alveolar cleft) and soft tissue (such as treatment of hemifacial macrosomia). Several attempts have been done to reconstruct impaired temporomandibular joint. Also, SCs with or without bone scaffolds and growth factors have been used to regenerate bone following distraction osteogenesis of mandibular bone or maxillary expansion. Current evidence shows that SCs also have potential to be used to regenerate infrabony alveolar defects and move the teeth into regenerated areas. Future application of SCs in orthodontics could involve accelerating tooth movement, regenerating resorbed roots and expanding tooth movement limitations. However, evidence supporting these roles is weak and further studies are required to evaluate the possibility of these ideas.

Strategies of enhancing bone regenerate formation in distraction osteogenesis

Distraction osteogenesis (DO) is a commonly used technique in multiple orthopedic sub-specialties, including trauma, oncology and pediatrics. This technique aims to produce new bone formation in the distraction gap in a controlled manner. The issue with this technique has been the high risk of complications, one of which is poor regenerate formation during the distraction process. Although several factors (including patient and operative factors) and techniques (including surgical, mechanical and pharmacological) have been described to ensure successful regenerate formation during the process of DO, these factors are sometimes difficult to control clinically. Our aim from this review is to highlight the different factors that affect DO, modalities to assess the regenerate and review treatment options for poor regenerate in the distraction gap. In addition, we propose a management protocol derived from the available literature that can be used to facilitate the management of inadequate regenerate formation.

Enhancement of bone regeneration with the accordion technique via HIF-1α/VEGF activation in a rat distraction osteogenesis model

Axial micromotion of bone fragments promotes callus formation and bone healing during the process of distraction osteogenesis (DO). This study investigated the effects of the combined axial compression and distraction (accordion) technique on bone regeneration in rat DO model. Male Sprague-Dawley rats (n = 62) underwent right tibial transverse osteotomy and were randomly divided into four groups after lengthening: control (no manipulation) and three experimental groups assigned on the basis of the period of accordion manoeuvres in the consolidation phase (Groups 1, 2, and 3 with accordion technique applied at Weeks 1, 3, and 5, respectively). Animals were terminated at 1 week after each accordion phase (i.e., Weeks 2, 4, and 6). Callus formation was monitored by X-ray radiography; new bone quality was evaluated by microcomputed tomography, histological analysis, and mechanical testing. Serum levels of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) were measured. Callus formation after accordion manoeuvre at Week 3 (Group 2) increased significantly over time of consolidation. The microcomputed tomography and mechanical analysis revealed Group 2 had more newly formed bone and superior mechanical properties in contrast to the other groups at termination. Histomorphological and immunohistochemical analyses confirmed a greater degree of osteogenesis and angiogenesis corresponding to increased serum levels of HIF-1α and VEGF in Group 2. The accordion technique was effective in promoting bone consolidation via activation of HIF-1α/VEGF during DO. The accordion technique may be used in the middle phase of bone consolidation to promote bone formation in patients undergoing DO treatment.

Quality of life and complications at the different stages of bone transport for treatment infected nonunion of the tibia

The aim of this study was to assess Physical Component Summary (PCS), Mental Component Summary (MCS) of the Mos 36-item Short Form Health Survey (SF-36) score, and the virtual Analogue Scale (VAS) of pain during the treatment period and the complication rate associated with infected nonunion of the tibia managed surgically by bone transport.This is a retrospective analysis of prospectively collected data in a consecutive patient cohort. Patients suffering from infected nonunion of the tibia were treated by bone transport from 2012 to 2014. Follow-up was for at least 2 years after complete osseous consolidation. Standardized treatment included bacterial eradication by segmental resection, bone transport using Ilizarov apparatus, and docking maneuver. The main outcome measurements consisted of the quality of life (PCS and MCS scores) and the VAS of pain during the different stages of therapy. In addition, all complications were documented.Our series comprised 12 men and 3 women with an average age of 36.9 years (range: 20-55 years). All patients previously undergone an average of 2.9 operations (range: 1-6 operations). In all patients, bone defects were present with a mean size of 7.5 cm (range: 3-12 cm), and all patients were suffering from soft tissue defects (range: 5-17 cm). The mean external fixator time (EFT) was 48 weeks (range: 30-62 weeks) and the mean external fixation index was 43.1 days/cm (range: 33-62 days/cm). All patients achieved bone union, and no recurrence of infection was observed. According to the Paley classification, patients suffered 15 minor and 13 major complications. The average complication rate per patient comprised of 1.0 minor and 0.9 major complications. Bone grafting was required in 6 cases at the docking site. One patient suffered from equinus deformity, and refused any further surgical procedures. We performed 28 operations in 15 patients (average 1.9 operations per patient). After the period of bone transport, PCS and MCS scores increased continuously. After completed consolidation, the average MCS score was comparable to a normal collective, and the average VAS score was 1.87 (range: 0-3).Bone transport is a safe option for the treatment of infected nonunion of the tibia despite the high complication rate. The arduous and demanding nature of this treatment subjects patient to considerable the pain, mental, and physical stress. The average VAS scores, PCS, and MCS scores significantly improve at final follow-up. It is essential to communicate this fact to the patients and their relatives before the application of the frame in order to increase their compliance with the long and emotionally draining treatment.

Bone transport versus acute shortening for the management of infected tibial non-unions with bone defects

INTRODUCTION

This study compared bone transport to acute shortening/lengthening in a series of infected tibial segmental defects from 3 to 10cm in length.

METHODS

In a retrospective comparative study 42 patients treated for infected tibial non-union with segmental bone loss measuring between 3 and 10cm were included. Group A was treated with bone transport and Group B with acute shortening/lengthening. All patients were treated by Ilizarov methods for gradual correction as bi-focal or tri-focal treatment; the treating surgeon selected either transport or acute shortening based on clinical considerations. The principle outcome measure was the external fixation index (EFI); secondary outcome measures included functional and bone results, and complication rates.

RESULTS

The mean size of the bone defect was 7cm in Group A, and 5.8cm in Group B. The mean time in external fixation in Group A was 12.5 months, and in Group B was 10.1 months. The external fixation index (EFI) measured 1.8 months/cm in Group A and 1.7 months/cm in Group B (P=0.09). Minor complications were 1.2 per patient in the transport group and 0.5 per patient in the acute shortening group (P=0.00002). Major complications were 1.0 per patient in the transport group versus 0.4 per patient in the acute shortening group (P=0.0003). Complications with permanent residual effects (sequelae) were 0.5 per patient in the transport group versus 0.3 per patient in the acute shortening group (P=0.28).

CONCLUSIONS

While both techniques demonstrated excellent results, acute shortening/lengthening demonstrated a lower rate of complications and a slightly better radiographic outcome. Bone grafting of the docking site was often required with both procedures.

LEVEL OF EVIDENCE

Level III; Retrospective comparative study.

Accordion technique combined with minimally invasive percutaneous decortication for the treatment of bone non-union

BACKGROUND

A variety of approaches have been used to treat oligotrophic or atrophic non-union. Conventional methods are often associated with great operative trauma, increased blood loss, a risk of re-infection, higher medical costs, and complications at the donor site. This study aimed to assess the clinical efficacy of the accordion technique combined with Minimally Invasive Percutaneous Decortication (MIPD) for these types of bone non-union.

METHODS

From January 2010 to December 2015, 20 patients with long bone aseptic non-unions of the lower extremities without bone defects who were treated with the accordion technique combined with MIPD. The limb-length discrepancy (LLD) was less than 2cm in all patients. None of the patients received autogenous bone grafts during follow-up. All surgeries were performed by the same surgeon, and the modified Application of methods of Ilizarov (ASAMI) criteria were used to evaluate the operative effectiveness.

RESULTS

A total of 20 patients were included in this study, and 1 patient was lost during follow-up. Fifteen of these patients presented with oligotrophic non-unions, and 5 patients presented with atrophic non-unions. The average follow-up period in these patients was 12.1 months (range: 8-42 months). The alternative compression and distraction procedure was repeated 1-3 times. Blood loss was 30 to 250ml during surgery. Ultimately, bone union was achieved in 19 patients and failed in 1 patient. The fractures healed within 4-8 months (average time: 5.9 months), and fracture healing was considered excellent in 19 patients and poor in 1 patient. Postoperative function was evaluated as excellent in 9 patients, good in 6 patients, fair in 4 patients, and poor in 1 patient.

CONCLUSION

The accordion technique combined with MIPD, which is a simple, minimally invasive procedure that does not require autologous bone grafting, resulted in a high bone union rate and good postoperative function.

Treatment Options for Nonunion With Segmental Bone Defects: Systematic Review and Quantitative Evidence Synthesis

OBJECTIVES

To determine which reconstruction treatment of long bones nonunion with segmental bone defects (SBDs) is effective to restore bone length and union with good function.

DATA SOURCES

PubMed was used to identify published literature on treatment of SBD caused by fracture nonunion regardless of infection between January 1975 and December 2014.

STUDY SELECTION

We included retrospective cohort studies with a minimum sample size of 10 consecutive patients with minimum follow-up of 18 months and available data on radiographic and functional outcomes.

DATA EXTRACTION

Literature review revealed 24 publications with a sample size of 504 patients (395 males, 109 females). Data on bone union and functional outcome and complications were collected and analyzed based on validated classification systems.

DATA SYNTHESIS

Two outcome groups were categorized for bone union and functional outcome, success, and failure. We then performed heterogeneity test to examine the variability or differences in the methods used by these studies and based on that we determined whether the fixed effect or random effect method is appropriate in examining the summary or pool estimate. Pool estimate was examined for bone union and functional outcome in each surgical modality and in each anatomic location when data were available.

CONCLUSIONS

Treatment of SBD can be challenging. This quantitative evidence synthesis shows that bone union was achieved by different procedures with variable bone union and functional outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Limb reconstruction after traumatic bone loss

A variety of options exist to reconstruct limbs following traumatic bone loss. The management of these injuries is challenging and often requires prolonged and potentially painful treatment. The Ilizarov technique of bone transport using circular external fixators is widely used for limb reconstruction of large bone defects. Other techniques include vascularised fibular grafting, the use of induced pseudosynovial membranes combined with cancellous autologous bone grafts and the use of autologous, allogeneic or synthetic bone grafts on their own for smaller defects. Future directions include further research on bone tissue engineering using stem cell therapy and growth factors such as bone morphogenetic proteins. The purpose of this Continuing Medical Education article is to describe the key limb reconstructive techniques that may be employed to treat traumatic bone loss. In particular, this article is intended to serve as a revision tool for those preparing for postgraduate examinations.

Infected nonunion of tibia

Infected nonunions of tibia pose many challenges to the treating surgeon and the patient. Challenges include recalcitrant infection, complex deformities, sclerotic bone ends, large bone gaps, shortening, and joint stiffness. They are easy to diagnose and difficult to treat. The ASAMI classification helps decide treatment. The nonunion severity score proposed by Calori measures many parameters to give a prognosis. The infection severity score uses simple clinical signs to grade severity of infection. This determines number of surgeries and allows choice of hardware, either external or internal for definitive treatment. Co-morbid factors such as smoking, diabetes, nonsteroidal anti-inflammatory drug use, and hypovitaminosis D influence the choice and duration of treatment. Thorough debridement is the mainstay of treatment. Removal of all necrotic bone and soft tissue is needed. Care is exercised in shaping bone ends. Internal fixation can help achieve union if infection was mild. Severe infections need external fixation use in a second stage. Compression at nonunion site achieves union. It can be combined with a corticotomy lengthening at a distant site for equalization. Soft tissue deficit has to be covered by flaps, either local or microvascular. Bone gaps are best filled with the reliable technique of bone transport. Regenerate bone may be formed proximally, distally, or at both sites. Acute compression can fill bone gaps and may need a fibular resection. Gradual reduction of bone gap happens with bone transport, without need for fibulectomy. When bone ends dock, union may be achieved by vertical or horizontal compression. Biological stimulus from iliac crest bone grafts, bone marrow aspirate injections, and platelet concentrates hasten union. Bone graft substitutes add volume to graft and help fill defects. Addition of rh-BMP-7 may help in healing albeit at a much higher cost. Regeneration may need stimulation and augmentation. Induced membrane technique is an alternative to bone transport to fill gaps. It needs large amounts of bone graft from iliac crest or femoral canal. This is an expensive method physiologically and economically. Infection can resorb the graft and cause failure of treatment. It can be done in select cases after thorough eradication of infection. Patience and perseverance are needed for successful resolution of infection and achieving union.

Assessment of Multipotent Mesenchymal Stromal Cells in Bone Marrow Aspirate From Human Calcaneus

Bone marrow aspirates (BMAs), owing to their innate osteogenic potential, are well-documented supplements to osteoconductive and/or osteoinductive materials. The calcaneal body provides foot and ankle surgeons a convenient harvest site with low morbidity and minimal cost. In the present study, we sought to identify and characterize multipotent mesenchymal stromal cells (MSCs) in BMAs harvested from the human calcaneal body. Ten healthy patients aged 18 to 65 years were enrolled in the present study. BMAs were harvested from the patients without any reported postoperative complications related to the harvest. Cells isolated from all the aspirates were adherent to culture plates and expressed positive MSC surface markers (CD105, CD90, and CD73) and a low level of negative MSC markers (CD34 and CD45). The cells maintained the ability to proliferate and differentiate into cells of mesenchymal lineages. The BMAs from the human calcaneal body offer a healthy source of multipotent MSCs.

Treatment of post-traumatic chronic osteomyelitis of lower limbs by bone transport technique using mono-lateral external fixator: Follow-up study of 18 cases

PURPOSE

To review the results of the treatment of post-traumatic chronic osteomyelitis of lower limbs by bone transport technique using mono-lateral external fixator.

PATIENTS AND METHODS

A total of 18 patients with post-traumatic chronic osteomyelitis of lower limbs were treated by bone transport technique using mono-lateral external fixator in this study. Seven cases (patients No. 1-7) were performed early BGPO (autologous ilium bone grafting and plate osteosynthesis) intervention after BT (bone transport). The end results were assessed by the criteria of ASAMI and Paley et al. Some data between the cases with and without the intervention of early BGPO were subjected to statistical analysis of Student's t-test.

RESULTS

The overall average time for union was 10.8 months. The average union time of the non-early BGPO cases was 52.27 ± 7.82 weeks while the early BGPO cases took a shorter time of 36.86 ± 5.34 weeks (P < 0.001). The overall average duration from bone transport to removal of external fixator was 10.0 months. The average duration from bone transport to removal of external fixator in the non-early BGPO cases was 51.55 ± 7.45 weeks while the early BGPO cases took a shorter time of 29.29 ± 5.47 weeks (P < 0.001). The overall average of BHI was 1.77 months cm(-1). The average of BHI in the non-early BGPO cases was 2.25 ± 0.25 months cm(-1) and the average BHI of the early BGPO cases was 1.22 ± 0.114 months cm(-1) (P < 0.001). There were 31 additional surgeries and 38 complications in total after bone transport treatment. The bone results were excellent in 15 cases, good in 3 cases. The functional results were excellent in 9 cases, good in 6 cases and fair in 3 cases.

CONCLUSIONS

1. Bone transport technique using mono-lateral external fixator is an effective method for the treatment of post-traumatic chronic osteomyelitis. 2. Early BGPO intervention after bone transport is a feasible method to shorten the external fixation time and the total duration of treatment.

Assessment of Bone Marrow Aspiration Site Pain in Foot and Ankle Surgery

Bone marrow aspiration (BMA) is a validated technique to harvest progenitor cells. BMA has many uses in foot and ankle surgery; however, donor site morbidity is a concern. The purpose of this study was to compare the Visual Analog Scale (VAS) pain scores after BMA at 3 different sites (iliac crest, distal tibia, and calcaneus) over a 12-week postoperative recovery period. This was an institutional review board-approved prospective study of 40 patients who underwent BMA as an adjunct to their primary foot and ankle procedure. Each patient had BMA harvested from the ipsilateral anterior iliac crest, distal tibia, and lateral calcaneus at the time of surgery. Patient follow-up questionnaire forms were filled out at 2, 4, 8, and 12 weeks, with the primary outcome measure being VAS pain scores. Mean VAS scores averaged over the 12-week follow-up period were significantly higher in the calcaneus (20.8 ± 28.6) compared with the distal tibia (7.7 ± 17.6) and the iliac crest (4.2 ± 12.4; P < .05). No significant difference was found between the distal tibia and the iliac crest sites. At 12 weeks, all sites were about equal and without appreciable pain. Our data suggested that donor site selection for BMA affects postoperative pain levels, with BMA from the calcaneus resulting in significantly higher pain scores when compared with the iliac crest or distal tibia. The VAS pain score for the calcaneus was likely confounded by the high number of hindfoot/ankle surgeries performed in the ipsilateral foot.

LEVELS OF EVIDENCE

Therapeutic, Level II: Prospective, comparative trial.

The Accordion Maneuver: A Noninvasive Strategy for Absent or Delayed Callus Formation in Cases of Limb Lengthening

The distraction osteogenesis (DO) technique has been used worldwide to treat many orthopaedic conditions. Although successful, absent or delayed callus formation in the distraction gap can lead to significant morbidities. An alternate cycle of distraction-compression (accordion maneuver) is one approach to accelerate bone regeneration. The primary aim of our study is to report our experience with the accordion maneuver during DO and to provide a detailed description of this technique, as performed in our center. The secondary aim is to present a review of the literature regarding the use of accordion maneuver. We reviewed the database of all patients undergoing limb lengthening from the year of 1997 to 2012. Four patients (6.15%) out of 65 showed poor bone regenerate in their tibiae and therefore accordion maneuver was applied for a mean of 6.75 weeks. Of these, three patients have had successful outcome with this technique. The literature showed that this technique is successful approach to trigger bone healing. However, details of how and when to apply this combination of distraction-compression forces were lacking. In conclusion, the accordion technique is safe noninvasive approach to promote bone formation, thus avoiding more invasive surgical procedures in cases of poor callus formation in limb lengthening.

Comprehensive Review of Adipose Stem Cells and Their Implication in Distraction Osteogenesis and Bone Regeneration

Bone is one of the most dynamic tissues in the human body that can heal following injury without leaving a scar. However, in instances of extensive bone loss, this intrinsic capacity of bone to heal may not be sufficient and external intervention becomes necessary. Several techniques are available to address this problem, including autogenous bone grafts and allografts. However, all these techniques have their own limitations. An alternative method is the technique of distraction osteogenesis, where gradual and controlled distraction of two bony segments after osteotomy leads to induction of new bone formation. Although distraction osteogenesis usually gives satisfactory results, its major limitation is the prolonged duration of time required before the external fixator is removed, which may lead to numerous complications. Numerous methods to accelerate bone formation in the context of distraction osteogenesis have been reported. A viable alternative to autogenous bone grafts for a source of osteogenic cells is mesenchymal stem cells from bone marrow. However, there are certain problems with bone marrow aspirate. Hence, scientists have investigated other sources for mesenchymal stem cells, specifically adipose tissue, which has been shown to be an excellent source of mesenchymal stem cells. In this paper, the potential use of adipose stem cells to stimulate bone formation is discussed.

Management of infected nonunion of the long bones by a multidisciplinary team

Infected nonunion of a long bone continues to present difficulties in management. In addition to treating the infection, it is necessary to establish bony stability, encourage fracture union and reconstruct the soft-tissue envelope. We present a series of 67 infected nonunions of a long bone in 66 patients treated in a multidisciplinary unit. The operative treatment of patients suitable for limb salvage was performed as a single procedure. Antibiotic regimes were determined by the results of microbiological culture. At a mean follow-up of 52 months (22 to 97), 59 patients (88%) had an infection-free united fracture in a functioning limb. Seven others required amputation (three as primary treatment, three after late failure of limb salvage and one for recalcitrant pain after union). The initial operation achieved union in 54 (84%) of the salvaged limbs at a mean of nine months (three to 26), with recurrence of infection in 9%. Further surgery in those limbs that remained ununited increased the union rate to 62 (97%) of the 64 limbs treated by limb salvage at final follow-up. The use of internal fixation was associated with a higher risk of recurrent infection than external fixation.

Accelerated Bone Formation in Distracted Alveolar Bone After Injection of Recombinant Human Bone Morphogenetic Protein-2

BACKGROUND

This study evaluates the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on the quality and quantity of regenerated bone when injected into distracted alveolar bone.

METHODS

Sixteen adult beagle dogs were assigned to either the control or rhBMP-2 group. After distraction was completed, an rhBMP-2 dose of 330 μg in 0.33 mL was injected slowly into the distracted alveolar crest of the mesial, middle, and distal parts of the alveolar bone in the experimental group. Histologic and microcomputed tomography analyses of regenerated bone were done after 2 and 6 weeks of consolidation.

RESULTS

After 6 weeks of consolidation, the vertical defect height in the middle of the regenerated bone was significantly lower in the rhBMP-2 group (2.2 mm) than in the control group (3.4 mm) (P <0.05). Additionally, the width of the regenerated bone was significantly greater in the rhBMP-2 group (4.3 mm) than in the control group (2.8 mm) (P <0.05). The bone density and volume of regenerated bone in the rhBMP-2 group were greater than in the control group after 6 weeks of consolidation (P <0.001).

CONCLUSION

Injection of rhBMP-2 into regenerated bone after a distraction osteogenesis procedure significantly increased bone volume in the dentoalveolar distraction site and improved both the width and height of the alveolar ridge and increased the bone density.

Use of demineralized bone matrix in the extremities

Autologous bone graft is considered as the gold standard for all indications for bone grafting procedures but the limited availability and complications in donor site resulted in seeking other options like allografts and bone graft substitutes. Demineralized bone matrix (DBM) is an allograft product with no quantity limitation. It is an osteoconductive material with osteoinductive capabilities, which vary among different products, depending on donor characteristics and differences in processing of the bone. The purpose of the present review is to provide a critical review of the existing literature concerning the use of DBM products in various procedures in the extremities. Clinical studies describing the use of DBM alone or in combination with other grafting material are available for only a few commercial products. The Level of Evidence of these studies and the resulting Grades of Recommendation are very low. In conclusion, further clinical studies of higher quality are required in order to improve the Recommendation Grades for or against the use of DBM products in bone grafting procedures.

Effect of heterologous bone marrow mononuclear cell transplantation on midpalatal expansion in rats

The aim of this study was to explore whether bone marrow mononuclear cell (BMMC) transplantation is able to accelerate the bone remodeling induced by midpalatal expansion in rats. A total of 48 male Sprague-Dawley rats (mean weight, 208.36±7.32 g) were divided into control and midpalatal expansion with or without BMMC transplantation groups. Histological and morphological changes were observed in each group. The osteogenic activities and differential potentials of the transplanted BMMCs labeled with bromodeoxyuridine in the midpalatal bone tissue were assessed by osteocalcin expression. The receptor activator of nuclear factor κB ligand (RANKL)/osteoprotegerin (OPG) ratio was determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to reflect the equilibrium between bone resorption and formation. The results demonstrated that the width of the maxillary dental arch increased distinctly within 2 weeks of midpalatal expansion with BMMC transplantation. The morphology of the midpalatal suture in this group changed significantly; the cartilage was completely replaced by fibrous-like tissue expressing osteocalcin. The palatal bone was reorganized from a cancellous form into a mature compact structure after an additional 2-week relapse period. Immunostaining results indicated that the heterologous transplanted BMMCs survived and differentiated into osteoblasts during the remodeling induced by midpalatal expansion. The RANKL/OPG expression ratio significantly decreased after 2 weeks of midpalatal expansion with BMMC transplantation due to the inhibition of RANKL expression. Heterologous BMMC transplantation appears to accelerate the midpalatal bone remodeling induced by expansion of the rats through increasing the number of osteoprogenitor cells and regulating the RANKL-OPG signaling pathway.

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.

Bone marrow derived stem cells in joint and bone diseases: a concise review

Stem cells have huge applications in the field of tissue engineering and regenerative medicine. Their use is currently not restricted to the life-threatening diseases but also extended to disorders involving the structural tissues, which may not jeopardize the patients' life, but certainly influence their quality of life. In fact, a particularly popular line of research is represented by the regeneration of bone and cartilage tissues to treat various orthopaedic disorders. Most of these pioneering research lines that aim to create new treatments for diseases that currently have limited therapies are still in the bench of the researchers. However, in recent years, several clinical trials have been started with satisfactory and encouraging results. This article aims to review the concept of stem cells and their characterization in terms of site of residence, differentiation potential and therapeutic prospective. In fact, while only the bone marrow was initially considered as a "reservoir" of this cell population, later, adipose tissue and muscle tissue have provided a considerable amount of cells available for multiple differentiation. In reality, recently, the so-called "stem cell niche" was identified as the perivascular space, recognizing these cells as almost ubiquitous. In the field of bone and joint diseases, their potential to differentiate into multiple cell lines makes their application ideally immediate through three main modalities: (1) cells selected by withdrawal from bone marrow, subsequent culture in the laboratory, and ultimately transplant at the site of injury; (2) bone marrow aspirate, concentrated and directly implanted into the injury site; (3) systemic mobilization of stem cells and other bone marrow precursors by the use of growth factors. The use of this cell population in joint and bone disease will be addressed and discussed, analysing both the clinical outcomes but also the basic research background, which has justified their use for the treatment of bone, cartilage and meniscus tissues.

The composite of bone marrow concentrate and PRP as an alternative to autologous bone grafting

One possible alternative to the application of autologous bone grafts represents the use of autologous bone marrow concentrate (BMC). The purpose of our study was to evaluate the potency of autologous platelet-rich plasma (PRP) in combination with BMC. In 32 mini-pigs a metaphyseal critical-size defect was surgically created at the proximal tibia. The animals were allocated to four treatment groups of eight animals each (1. BMC+CPG group, 2. BMC+CPG+PRP group, 3. autograft group, 4. CPG group). In the BMC+CPG group the defect was filled with autologous BMC in combination with calcium phosphate granules (CPG), whereas in the BMC+CPG+PRP group the defect was filled with the composite of autologous BMC, CPG and autologous PRP. In the autograft group the defect was filled with autologous cancellous graft, whereas in the CPG group the defect was filled with CPG solely. After 6 weeks radiological and histomorphometrical analysis showed significantly more new bone formation in the BMC+CPG+PRP group compared to the BMC+CPG group and the CPG group. There were no significant differences between the BMC+CPG+PRP group and the autograft group. In the PRP platelets were enriched significantly about 4.7-fold compared to native blood. In BMC the count of mononuclear cells increased significantly (3.5-fold) compared to the bone marrow aspirate. This study demonstrates that the composite of BMC+CPG+PRP leads to a significantly higher bone regeneration of critical-size defects at the proximal tibia in mini-pigs than the use of BMC+CPG without PRP. Furthermore, within the limits of the present study the composite BMC+CPG+PRP represents a comparable alternative to autologous bone grafting.

The role of erythropoietin and bone marrow concentrate in the treatment of osteochondral defects in mini-pigs

Background

All available treatment options for osteochondral and chondral defects do not restore hyaline cartilage and are limited to decreasing associated pain, and maintaining or improving joint function. The purpose of this study was to evaluate the potential of erythropoietin (EPO) in combination with bone marrow aspiration concentrate (BMAC) in the treatment of osteochondral defects of mini-pigs.

Methods

14 Goettinger mini-pigs, in which a 6×10 mm osteochondral defect in the medial femoral condyle of both knee joints was created, were randomized into four groups: biphasic scaffold alone, scaffold with EPO, scaffold with BMAC and scaffold in combination with EPO and BMAC. After 26 weeks all animals were euthanized and histological slides were evaluated using a modified ÓDriscoll Score.

Results

In the therapy groups, areas of chondrogenic tissue that contained collagen II were present. Adding EPO (p = 0.245) or BMAC (p = 0.099) alone to the scaffold led to a non-significant increase in the score compared to the control group. However, the combination of EPO and BMAC in the implanted scaffold showed a significant improvement (p = 0.02) in the histological score.

Conclusion

The results of our study show that in mini-pigs, the combination of EPO and BMAC leads to an enhanced osteochondral healing. However, additional research is necessary to further improve the repair tissue and to define the role of MSCs and EPO in cartilage repair.

Bone transport with an external fixator and a locking plate for segmental tibial defects

Although gradual bone transport may permit the restoration of large-diameter bones, complications are common owing to the long duration of external fixation. In order to reduce such complications, a new technique of bone transport involving the use of an external fixator and a locking plate was devised for segmental tibial bone defects. A total of ten patients (nine men, one woman) with a mean age at operation of 40.4 years (16 to 64) underwent distraction osteogenesis with a locking plate to treat previously infected post-traumatic segmental tibial defects. The locking plate was fixed percutaneously to bridge proximal and distal segments, and was followed by external fixation. After docking, percutaneous screws were fixed at the transported segment through plate holes. At the same time, bone grafting was performed at the docking site with the external fixator removed. The mean defect size was 5.9 cm (3.8 to 9.3) and mean external fixation index was 13.4 days/cm (11.8 to 19.5). In all cases, primary union of the docking site and distraction callus was achieved, with an excellent bony result. There was no recurrence of deep infection or osteomyelitis, and with the exception of one patient with a pre-existing peroneal nerve injury, all achieved an excellent or good functional result. With short external fixation times and low complication rates, bone transport with a locking plate could be recommended for patients with segmental tibial defects.

The early phase influence of bone marrow concentrate on metaphyseal bone healing

Bone marrow concentrate (BMC) contains high densities of progenitor cells. Therefore, in critical size defects BMC may have the potency to support bone healing. The aim of this study was to investigate the effect of BMC in combination with calcium phosphate granules (CPG) on bone defect healing in a metaphyseal long bone defect in mini-pigs. A metaphyseal critical-size bone defect at the proximal tibia of 24 mini-pigs was filled with CPG combined with BMC, CPG solely (control group) or with an autograft. Radiological and histomorphometrical evaluations after 6 weeks (42 days) showed significantly more bone formation in the BMC group in the central area of the defect zone and the cortical defect zone compared to the CPG group. At the same time the resorption rate of CPG increased significantly in the BMC group. Nevertheless, compared to the BMC group the autograft group showed a significantly higher new bone formation radiologically and histomorphometrically. In BMC the count of mononuclear cells was significantly higher compared to the bone marrow aspirate (3.5-fold). The mesenchymal progenitor cell characteristics of the cells in BMC were confirmed by flow cytometry. Cells from BMC created significantly larger colonies of alkaline phosphatase-positive colony forming units (CFU-ALP) (4.4-fold) compared to cells from bone marrow aspirate. Nevertheless, even in the BMC group complete osseous bridging was only detectable in isolated instances of the bone defects. Within the limitations of this study the BMC+CPG composite promotes bone regeneration in the early phase of bone healing significantly better than the isolated application of CPG. However, the addition of BMC does not lead to a solid fusion of the defect in the early phase of bone healing an still does not represent an equal alternative to autologous bone.