The treatment of atrophic, recalcitrant long-bone nonunion in the upper extremity with human recombinant bone morphogenetic protein-7 (rhBMP-7) and plate fixation: A retrospective review

INTRODUCTION

Recombinant Human Bone Morphogenetic Protein-7 (rhBMP-7) has been shown to promote fracture healing in both clinical studies and basic science models, however, there is little information from large-scale studies of its use for human nonunion. The purpose of this study was to determine the safety and efficacy of rhBMP-7 in the treatment of atrophic human long-bone nonunions in the upper extremity.

PATIENTS AND METHODS

This was a single center, retrospective, longitudinal cohort study of patients treated with compression plating and the application of rhBMP-7 in isolation to a long-bone nonunion. Patients over sixteen years of age with an atrophic, aseptic nonunion of a humerus, radius, ulna or clavicle were eligible for inclusion.

RESULTS

We identified seventy eligible patients who were treated with rhBMP-7 for a long-bone nonunion between July 1997 and April 2012. The mean age of the patients at the time of treatment with rhBMP-7 was 50.7 years (range, 20-92 years). Five patients were lost to follow-up prior to definitive clinical or radiographic union. During the one-year post-operative period fifty-six patients had achieved union and two patients developed a stable fibrous union after the index procedure. Two patients had early implant failure and five patients had persistent nonunion. Thus, the union rate following initial surgery was 89% (58/65) and four of the five nonunion patients went on to heal following revision open reduction and internal fixation.

CONCLUSION

We found that the application of rhBMP-7 for upper extremity nonunion was an effective method (89% union rate) of treating this challenging pathology. Additionally, if not initially successful, further reconstruction was not compromised by rhBMP-7 use.

Open reduction and internal fixation of three- and four-part proximal humeral fractures by intra-focal distraction: observational study of twenty five cases

PURPOSE

Reduction and fixation of proximal humerus fracture (PHF) by intra-focal distraction with a cemented device is seldom used. A cementless stem called JUST was developed to simplify and standardise reduction and fixation of three- or four-part fractures (3-/4-PFs). This study is designed to evaluate the performances of this device. In addition, we compared the results to those of a previous study based on cemented stems.

METHOD

Twenty-five patients underwent surgery between 2009 and 2011: ten 3-PFs and 15 4-PFs, with a median age of 65.5 and 71 years, respectively. The reduction and fixation device comprises a staple placed in the humeral head and a cementless stem impacted in the diaphysis that works like a jack. Median follow-up was 28 months.

RESULTS

For the ten 3-PFs, the median raw and weighted Constant score were 66.5 and 86, respectively. Only one case presented with secondary displacement. All fractures healed and there was only one case of avascular necrosis. For the 15 4-PFs, the median raw and weighted Constant score were 64 and 76, respectively. Only one case of secondary cephalic displacement was observed and no cases of tuberosity displacement were observed. All fractures healed except for one case of pseudarthrosis of the lesser tuberosity. Five cases of avascular necrosis were observed.

CONCLUSIONS

This device resolves the mechanical difficulties relating to fixation of 3- and 4-PFs by providing stable fixation but does not prevent the risk of avascular necrosis. The cementless stem is more convenient but does not yield better results than the cemented stem.

Complications and Rates of Subsequent Lumbar Surgery Following Lumbar Total Disc Arthroplasty and Lumbar Fusion

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To examine complications and rates of subsequent surgery following lumbar spinal fusion (LF) and lumbar total disc arthroplasty (TDA) at up to 5-year follow-up.

SUMMARY OF BACKGROUND DATA

LF is commonly used in the management of degenerative disc disease causing pain refractory to nonoperative management. Lumbar TDA was developed as an alternative to fusion with the theoretical advantage of reducing rates of adjacent segment pathology and reoperation. Most prior reports comparing these 2 interventions have come from industry-sponsored investigational device exemption trials and no large-scale administrative database comparisons exist.

METHODS

The California Office of Statewide Health Planning and Development discharge database was queried for patients aged 18 to 65 years undergoing lumbar TDA and LF for degenerative disc disease from 2004 to 2010. Patient characteristics were collected, and rates of complications and readmission were identified. Rates of repeat lumbar surgery were calculated at 90-day and 1-, 3-, and 5-year follow-up intervals.

RESULTS

A total of 52,877 patients met the inclusion criteria (LF = 50,462, TDA = 2415). Wound infections were more common following LF than TDA (1.03% vs. 0.25%, P < 0.001). Rates of subsequent lumbar surgery at 90-day and 1-year follow-up were lower with lumbar TDA than LF (90-day-TDA: 2.94% vs. LF: 4.01%, P = 0.007; 1-yr-TDA: 3.46% vs. LF: 4.78%, P = 0.009). However, there were no differences in rates of subsequent lumbar surgery between the 2 groups at 3-year and 5-year follow-up.

CONCLUSION

Lumbar TDA was associated with fewer early reoperations, though beyond 1 year, rates of reoperation were similar. Lumbar TDA may be associated with fewer acute infections, though this may be approach related and unrelated to the device itself.

LEVEL OF EVIDENCE

3.

Polystyrene scaffolds based on microfibers as a bone substitute; development and in vitro study

We created non-resorbable porous scaffolds of polystyrene by electrospinning usable as a bone grafting material. Aligned and random fibers were prepared with a diameter ranging from 1 to 4.5μm. Influence of microfiber diameter and alignment were determined by culturing MC3T3 osteoblast-like cells and evaluation of adherence, proliferation and differentiation at day 14 and 28 on the scaffolds. Scanning electron microscopy (SEM), nanocomputed tomography (nanoCT) and confocal microscopy were used to observe microfibers and morphology of cells seeded on the scaffolds. Nile Red was used to label the fibers, DAPI for nuclear staining and calcein for the calcium/phosphate deposits. MC3T3 were more adherent on the randomly distributed fibers having the highest diameter. MC3T3 proliferated equally on scaffolds made with aligned fibers but cell density was lower on random fibers with the smaller diameter. Alkaline phosphatase activity (a marker of osteoblastic differentiation) was not influenced by the fibers apart from on random fibers with the smallest diameter. Calcospherites also developed at the surface of the fibers in long term culture. Cytometric determination of the nuclei shape factors evidenced that cells were elongated along the main direction of fibers only on the aligned fibers. This study shows that porous scaffolds based on microfibers allow adhesion, spreading, orientation and proliferation of cells.

STATEMENT OF SIGNIFICANCE

We prepared polystyrene porous scaffolds composed of microfibers as a bone substitute by electrospinning. Polystyrene is a cytocompatible and non-resorbable polymer which can support osteoconduction. Scaffolds with different micro-diameters and orientation, (aligned and random) were seeded with osteoblast-like cells to evaluate cell adherence, proliferation and differentiation. Characterization of microfibers and cell morphology was done by scanning electron microscopy, nanocomputed tomography and confocal microscopy. We evidenced that initial adherence of cells was increased on randomly disposed fibers with a high diameter (3.5μm). Cell proliferation and differentiation seems not to be influenced by fiber diameter and orientation, apart from random fibers of 1μm diameter which had a lower cell attachment. Morphometric analysis of cell nuclei showed that cells were stretched along the aligned fibers.

In vivo drug release behavior and osseointegration of a doxorubicin-loaded tissue-engineered scaffold

This pre-clinical study presented a dual function of a doxorubicin-loaded scaffold for both chemotherapeutic agent delivery and bone formation.

Efficacy of Honeycomb TCP-induced Microenvironment on Bone Tissue Regeneration in Craniofacial Area

Artificial bone materials that exhibit high biocompatibility have been developed and are being widely used for bone tissue regeneration. However, there are no biomaterials that are minimally invasive and safe. In a previous study, we succeeded in developing honeycomb β-tricalcium phosphate (β-TCP) which has through-and-through holes and is able to mimic the bone microenvironment for bone tissue regeneration. In the present study, we investigated how the difference in hole-diameter of honeycomb β-TCP (hole-diameter: 75, 300, 500, and 1600 μm) influences bone tissue regeneration histologically. Its osteoconductivity was also evaluated by implantation into zygomatic bone defects in rats. The results showed that the maximum bone formation was observed on the β-TCP with hole-diameter 300μm, included bone marrow-like tissue and the pattern of bone tissue formation similar to host bone. Therefore, the results indicated that we could control bone tissue formation by creating a bone microenvironment provided by β-TCP. Also, in zygomatic bone defect model with honeycomb β-TCP, the result showed there was osseous union and the continuity was reproduced between the both edges of resected bone and β-TCP, which indicated the zygomatic bone reproduction fully succeeded. It is thus thought that honeycomb β-TCP may serve as an excellent biomaterial for bone tissue regeneration in the head, neck and face regions, expected in clinical applications.

The ProFHER (PROximal Fracture of the Humerus: Evaluation by Randomisation) trial - a pragmatic multicentre randomised controlled trial evaluating the clinical effectiveness and cost-effectiveness of surgical compared with non-surgical treatment for proximal fracture of the humerus in adults

BACKGROUND

Proximal humeral fractures account for 5-6% of all fractures in adults. There is considerable variation in whether or not surgery is used in the management of displaced fractures involving the surgical neck.

OBJECTIVE

To evaluate the clinical effectiveness and cost-effectiveness of surgical compared with non-surgical treatment of the majority of displaced fractures of the proximal humerus involving the surgical neck in adults.

DESIGN

A pragmatic parallel-group multicentre randomised controlled trial with an economic evaluation. Follow-up was for 2 years.

SETTING

Recruitment was undertaken in the orthopaedic departments of 33 acute NHS hospitals in the UK. Patient care pathways included outpatient and community-based rehabilitation.

PARTICIPANTS

Adults (aged ≥ 16 years) presenting within 3 weeks of their injury with a displaced fracture of the proximal humerus involving the surgical neck.

INTERVENTIONS

The choice of surgical intervention was left to the treating surgeons, who used techniques with which they were experienced. Non-surgical treatment was initial sling immobilisation followed by active rehabilitation. Provision of rehabilitation was comparable in both groups.

MAIN OUTCOME MEASURES

The primary outcome was the Oxford Shoulder Score (OSS) assessed at 6, 12 and 24 months. Secondary outcomes were the 12-item Short Form health survey, surgical and other shoulder fracture-related complications, secondary surgery to the shoulder or increased/new shoulder-related therapy, medical complications during inpatient stay and mortality. European Quality of Life-5 Dimensions data and treatment costs were also collected.

RESULTS

The mean age of the 250 trial participants was 66 years and 192 (77%) were female. Independent assessment using the Neer classification identified 18 one-part fractures, 128 two-part fractures and 104 three- or four-part fractures. OSS data were available for 215 participants at 2 years. We found no statistically or clinically significant differences in OSS scores between the two treatment groups (scale 0-48, with a higher score indicating a better outcome) over the 2-year period [difference of 0.75 points in favour of the surgery group, 95% confidence interval (CI) -1.33 to 2.84; p = 0.479; data from 114 surgery and 117 non-surgery participants] or at individual time points. We found no statistically significant differences between surgical and non-surgical group participants in SF-12 physical or mental component summary scores; surgical or shoulder fracture-related complications (30 vs. 23 respectively); those undergoing further shoulder-related therapy, either surgery (11 vs. 11 respectively) or other therapy (seven vs. four respectively); or mortality (nine vs. five respectively). The base-case economic analysis showed that, at 2 years, the cost of surgical intervention was, on average, £1780.73 more per patient (95% CI £1152.71 to £2408.75) than the cost of non-surgical intervention. It was also slightly less beneficial in terms of utilities, although this difference was not statistically significant. The net monetary benefit associated with surgery is negative. There was only a 5% probability of surgery achieving the criterion of costing < £20,000 to gain a quality-adjusted life-year, which was confirmed by extensive sensitivity analyses.

CONCLUSIONS

Current surgical practice does not result in a better outcome for most patients with displaced fractures of the proximal humerus involving the surgical neck and is not cost-effective in the UK setting. Two areas for future work are the setting up of a national database of these fractures, including the collection of patient-reported outcomes, and research on the best ways of informing patients with these and other upper limb fractures about initial self-care.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN50850043.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 24. See the NIHR Journals Library website for further project information.

Bone Grafting: Sourcing, Timing, Strategies, and Alternatives

Acute fractures, nonunions, and nonunions with bone defects or osteomyelitis often need bone graft to facilitate union. There are several factors to consider when it is determined that a bone graft is needed. These factors include the source of the bone graft (autograft vs. allograft), proper timing for placement of the bone graft, strategies to avoid further complications (particularly in the setting of osteomyelitis), and with the development of a variety of bone graft substitutes, whether alternatives to autograft are available and appropriate for the task at hand. Autograft bone has commonly been referred to as the "gold standard" of bone grafts, against which the efficacy of other grafts has been measured. The best timing for when to place a bone graft or substitute is also somewhat controversial, particularly after an open fracture or a potentially contaminated bed. The treatment of infected nonunions, particularly those that require a graft to facilitate healing, can be quite challenging. Typically, the infection is completely eradicated before placement of a bone graft, but achieving a sterile bed and the timing of a bone graft require strategic thinking and planning. This review outlines the benefits of autografts, the most suitable sites for harvesting bone grafts, the timing of bone graft procedures, the potential risks and benefits of grafting in the face of infection, and the currently available bone graft extenders.

Screw augmentation reduces motion at the bone-implant interface: a biomechanical study of locking plate fixation of proximal humeral fractures

BACKGROUND

Shear forces at the bone-implant interface lead to a loss of reduction after locking plate fixation of proximal humeral fractures. The aim of the study was to analyze the roles of medial support screws and screw augmentation in failure loads and motion at the bone-implant interface after locking plate fixation of proximal humeral fractures.

METHODS

Unstable 3-part fractures were simulated in 6 pairs of cadaveric humeri and were fixed with a DiPhos-H locking plate (Lima Corporate, Udine, Italy). An additional medial support screw was implanted in 1 humerus of every donor. The opposite humerus was stabilized with a medial support screw and additional bone cement augmentation of the 2 anteriorly directed head screws. Specimens were loaded in the varus bending position. Stiffness, failure loads, plate bending, and the motion at the bone-implant interface were evaluated using an optical motion capture system.

RESULTS

The mean load to failure was 669 N (standard deviation [SD], 117 N) after fixation with medial support screws alone and 706 N (SD, 153 N) after additional head screw augmentation (P = .646). The initial stiffness was 453 N/mm (SD, 4.16 N/mm) and 461 N/mm (SD, 64.3 N/mm), respectively (P = .594). Plate bending did not differ between the 2 groups. However, motion at the bone-implant interface was significantly reduced after head screw augmentation (P < .05).

CONCLUSION

The addition of bone cement to augment anteriorly directed head screws does not increase stiffness and failure loads but reduces motion at the bone-implant interface. Thus, the risk of secondary dislocation of the head fragment may be reduced.

Interventions for treating proximal humeral fractures in adults

BACKGROUND

Fracture of the proximal humerus, often termed shoulder fracture, is a common injury in older people. The management of these fractures varies widely. This is an update of a Cochrane Review first published in 2001 and last updated in 2012.

OBJECTIVES

To assess the effects (benefits and harms) of treatment and rehabilitation interventions for proximal humeral fractures in adults.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and other databases, conference proceedings and bibliographies of trial reports. The full search ended in November 2014.

SELECTION CRITERIA

We considered all randomised controlled trials (RCTs) and quasi-randomised controlled trials pertinent to the management of proximal humeral fractures in adults.

DATA COLLECTION AND ANALYSIS

Both review authors performed independent study selection, risk of bias assessment and data extraction. Only limited meta-analysis was performed.

MAIN RESULTS

We included 31 heterogeneous RCTs (1941 participants). Most of the 18 separate treatment comparisons were tested by small single-centre trials. The main exception was the surgical versus non-surgical treatment comparison tested by eight trials. Except for a large multicentre trial, bias in these trials could not be ruled out. The quality of the evidence was either low or very low for all comparisons except the largest comparison.Nine trials evaluated non-surgical treatment in mainly minimally displaced fractures. Four trials compared early (usually one week) versus delayed (three or four weeks) mobilisation after fracture but only limited pooling was possible and most of the data were from one trial (86 participants). This found some evidence that early mobilisation resulted in better recovery and less pain in people with mainly minimally displaced fractures. There was evidence of little difference between the two groups in shoulder complications (2/127 early mobilisation versus 3/132 delayed mobilisation; 4 trials) and fracture displacement and non-union (2/52 versus 1/54; 2 trials).One quasi-randomised trial (28 participants) found the Gilchrist-type sling was generally more comfortable than the Desault-type sling (body bandage). One trial (48 participants) testing pulsed electromagnetic high-frequency energy provided no evidence. Two trials (62 participants) provided evidence indicating little difference in outcome between instruction for home exercises versus supervised physiotherapy. One trial (48 participants) reported, without presentable data, that home exercise alone gave better early and comparable long-term results than supervised exercise in a swimming pool plus home exercise.Eight trials, involving 567 older participants, evaluated surgical intervention for displaced fractures. There was high quality evidence of no clinically important difference in patient-reported shoulder and upper-limb function at one- or two-year follow-up between surgical (primarily locking plate fixation or hemiarthroplasty) and non-surgical treatment (sling immobilisation) for the majority of displaced proximal humeral fractures; and moderate quality evidence of no clinically important difference between the two groups in quality of life at two years (and at interim follow-ups at six and 12 months). There was moderate quality evidence of little difference between groups in mortality in the surgery group (17/248 versus 12/248; risk ratio (RR) 1.40 favouring non-surgical treatment, 95% confidence interval (CI) 0.69 to 2.83; P = 0.35; 6 trials); only one death was explicitly linked with the treatment. There was moderate quality evidence of a higher risk of additional surgery in the surgery group (34/262 versus 16/261; RR 2.06, 95% CI 1.18 to 3.60; P = 0.01; 7 trials). Although there was moderate evidence of a higher risk of adverse events after surgery, the 95% confidence intervals for adverse events also included the potential for a greater risk of adverse events after non-surgical treatment.Different methods of surgical management were tested in 12 trials. One trial (57 participants) comparing two types of locking plate versus a locking nail for treating two-part surgical neck fractures found some evidence of slightly better function after plate fixation but also of a higher rate of surgically-related complications. One trial (61 participants) comparing a locking plate versus minimally invasive fixation with distally inserted intramedullary K-wires found little difference between the two implants at two years. Compared with hemiarthroplasty, one trial (32 participants) found similar results with locking plate fixation in function and re-operation rates, whereas another trial (30 participants) reported all five re-operations occurred in the tension-band fixation group. One trial (62 participants) found better patient-rated (Quick DASH) and composite shoulder function scores at a minimum of two years follow-up and a lower incidence of re-operation and complications after reverse shoulder arthroplasty (RSA) compared with hemiarthroplasty.No important between-group differences were found in one trial (120 participants) comparing the deltoid-split approach versus deltopectoral approach for non-contact bridging plate fixation, and two trials (180 participants) comparing 'polyaxial' and 'monaxial' screws in locking plate fixation. One trial (68 participants) produced some preliminary evidence that tended to support the use of medial support locking screws in locking plate fixation. One trial (54 participants) found fewer adverse events, including re-operations, for the newer of two types of intramedullary nail. One trial (35 participants) found better functional results for one of two types of hemiarthroplasty. One trial (45 participants) found no important effects of tenodesis of the long head of the biceps for people undergoing hemiarthroplasty.Very limited evidence suggested similar outcomes from early versus later mobilisation after either surgical fixation (one trial: 64 participants) or hemiarthroplasty (one trial: 49 participants).

AUTHORS' CONCLUSIONS

There is high or moderate quality evidence that, compared with non-surgical treatment, surgery does not result in a better outcome at one and two years after injury for people with displaced proximal humeral fractures involving the humeral neck and is likely to result in a greater need for subsequent surgery. The evidence does not cover the treatment of two-part tuberosity fractures, fractures in young people, high energy trauma, nor the less common fractures such as fracture dislocations and head splitting fractures.There is insufficient evidence from RCTs to inform the choices between different non-surgical, surgical, or rehabilitation interventions for these fractures.

Clinical Characteristics and Risk Factor Analysis for Lower-Extremity Amputations in Diabetic Patients With Foot Ulcer Complicated by Necrotizing Fasciitis

Patients with diabetes are at a higher risk of having diabetic foot ulcers (DFUs) or necrotizing fasciitis (NF). The present study aims to examine the clinical characteristics and associated risk factors for lower-extremity amputation (LEA) in patients with DFU complicated by NF.We retrospectively reviewed patients treated at a major diabetic foot center in Taiwan between 2009 and 2014. Of the 2265 cases 110 had lower-extremity NF. Limb preservation outcomes were classified as major LEA, minor LEA, or limb-preserved. Clinical characteristics, laboratory data, and bacterial culture results were collected for analysis.Of the 110 patients with NF, 100 had concomitant DFUs (NF with DFU) and the remaining 10 had no DFU (NF without DFU). None of the NF patients without DFU died nor had their leg amputated. Two NF patients with DFU died of complications. The amputation rate in the surviving 98 NF patients with DFU was 72.4% (46.9% minor LEA and 25.5% major LEA). Seventy percent of the NF patients without DFU had monomicrobial infections (60% with Streptococcus species), and 81.4% NF patients with DFU had polymicrobial infections. Anaerobic organisms were identified in 66% of the NF patients with DFU. Multinomial logistic regression analysis revealed an association between high-grade Wagner wound classification (Wagner 4 and Wagner 5) and LEA (adjusted odds ratio [aOR] = 21.856, 95% confidence interval [95% CI] = 1.625-203.947, P = 0.02 and aOR = 20.094, 95% CI = 1.968-205.216, P = 0.01 for major and minor LEA, respectively) for NF patients with DFU. In addition, a lower serum albumin level was associated with major LEA (OR = 0.066, P = 0.002).In summary, once DFUs were complicated by NF, the risk of amputation increased. Empirical treatment for NF patients with DFU should cover polymicrobial infections, including anaerobic organisms. The high-grade wound classification and low serum albumin level were associated with LEA.

Bone Morphogenetic Proteins in Spinal Surgery: What Is the Fusion Rate and Do They Cause Cancer?

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

The aim of this study was to determine the fusion rate using recombinant human bone morphogenetic protein (rhBMP) in spinal surgery and to estimate the risk of cancer subsequent to their use.

SUMMARY OF BACKGROUND DATA

rhBMP may obviate the need for iliac crest bone graft harvest and provides similar or higher fusion rates than autologous bone graft. Recently, there are concerns that rhBMPs may either cause cancer or accelerate progression.

METHODS

Patients were treated by 2 spine surgeons between 2002 and 2012. Inclusion criteria were patients who resided in the state of Victoria, Australia, undergoing lumbar fusion (anterior, lateral, posterior, and posterolateral) with rhBMP [either rhBMP-2 (Infuse) or rhBMP-7 (OP-1)]. Exclusion criteria were patients who reported having an invasive cancer diagnosis before the spinal fusion procedure. The occurrence of incident cancers was obtained from record linkage to the Victorian Cancer Registry.

RESULTS

A total of 527 patients were included in the cohort, with a mean follow-up of 4.4 years (1.8-11.5). Patients received Infuse in 77% of cases and OP-1 in 23%. The mean Infuse does was 10.2  mg (2.5-48.0) and 3.3  mg (1.7-6.6) for OP-1. There was no significant difference in fusion rates between Infuse (90.1%) and OP-1 (91.9%) (P = 0.42). The overall success of interbody fusion with rhBMP was 93.5% at 12 months. Twenty-seven patients were diagnosed with an invasive cancer since treatment (20 Infuse and 7 OP-1 patients). Comparing the observed numbers in our study cohort with those expected on the basis of the Victorian population's age and sex-specific rates, we observed that the study cohort was not at a significantly increased risk of cancer. The standardized incidence ratio for cancer overall (of any type) was 0.84 [95% confidence interval (95% CI) 0.56-1.21].

CONCLUSION

Off-label use of rhBMP provided high fusion rates with no evidence of a significantly increased risk of cancer.

LEVEL OF EVIDENCE

4.

Chin bone graft for maxillary alveolar cleft: indications and limitations

BACKGROUND

Alveolar bone grafting (ABG) is an important step in the management of patients with cleft lip and palate. Choice of autogenous bone grafting is critical to achieve the goals of alveolar cleft bone grafting. This study was designed to determine which situations are suitable for obtaining bone from the chin in ABG.

MATERIALS AND METHODS

In a retrospective study, the alveolar clefts that had been bone-grafted from the chin bone were selected from the archived files of the Oral and Maxillofacial Department, Mashhad University of Medical Sciences in 2004 to 2012. The patients were recalled and postoperative panoramic and lateral cephalometry views were obtained.

RESULTS

Seventeen patients were included in this study, with 53% females and 70.5% unilateral maxillary alveolar clefts. The follow-up was from 2 to 6 years. The mean age of the patients at the time of surgery was 17 ± 3.8 years.

CONCLUSION

Harvesting bone from the chin is easy and safe, with low morbidity. Considering the fact that the volume of the harvested bone is low, especially in the presence of unerupted mandibular canine, autogenous chin bone is recommended for late ABG, especially in unilateral cases when the plan is to close the gap in the arch orthodontically while there is no need for lateral piriform augmentation.

Morbidity associated with anterior iliac crest bone graft harvesting in children undergoing orthopaedic surgery: a prospective review

PURPOSE

Autologous iliac crest bone grafting is an integral part of many orthopaedic surgical procedures. Several studies have documented morbidity and prolonged pain following iliac crest bone graft harvesting in adults; however, in children there is a paucity of information. The purpose of the present study was to quantify the degree of pain and morbidity associated with anterior iliac crest graft harvesting in children undergoing non-spinal orthopaedic surgery.

METHODS

Patients were prospectively enrolled prior to orthopaedic surgery. A patient self-reported visual analogue score was used to record pain at specified time points following surgery. In addition, the patients were reviewed at 2 and 6 weeks, 3 months and 1 year after surgery to record any complications.

RESULTS

Data was collected on 33 patients (34 graft sites). Only one patient (2.94 %) had a complication, namely an injury to the lateral femoral cutaneous nerve. This resolved 3 months after surgery. 89 % of patients had no pain at the iliac crest graft harvest site 3 months after surgery. The three patients who had pain at 3 months had visual analogue scores of 1.0, 1.1 and 1.3, respectively.

CONCLUSION

This series reveals a very low complication rate and minimal iliac crest graft harvest site pain in children undergoing non-spinal orthopaedic surgery. In addition, the pain experienced is short-lived.

Draft Genome Sequence of a Necrotoxigenic Escherichia coli Isolate

Here, we present the draft genome sequence of a necrotoxigenic Escherichia coli strain isolated from a patient following a very rapidly evolving, lethal necrotizing fasciitis.

Printed three-dimensional anatomic templates for virtual preoperative planning before reconstruction of old pelvic injuries: initial results

BACKGROUND

Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy, difficult-to-access surgical sites, and the relatively low incidence of such cases. Proper evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the fracture. The goal of this study was to assess the use of three-dimensional (3D) printing techniques for surgical management of old pelvic fractures.

METHODS

First, 16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic data. Next, nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed models. The pelvic injuries were all type C, and the average time from injury to reconstruction was 11 weeks (range: 8-17 weeks). The workflow consisted of: (1) Printing patient-specific bone models based on preoperative computed tomography (CT) scans, (2) virtual fracture reduction using the printed 3D anatomic template, (3) virtual fracture fixation using Kirschner wires, and (4) preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined deformation. These models aided communication between surgical team members during the procedure. This technique was validated by comparing the preoperative planning to the intraoperative procedure.

RESULTS

The accuracy of the 3D printed models was within specification. Production of a model from standard CT DICOM data took 7 hours (range: 6-9 hours). Preoperative planning using the 3D printed models was feasible in all cases. Good correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine cases. The patients were followed for 3-29 months (median: 5 months). The fracture healing time was 9-17 weeks (mean: 10 weeks). No delayed incision healing, wound infection, or nonunions occurred. The results were excellent in two cases, good in five, and poor in two based on the Majeed score.

CONCLUSIONS

The 3D printing planning technique for pelvic surgery was successfully integrated into a clinical workflow to improve patient-specific preoperative planning by providing a visual and haptic model of the injury and allowing patient-specific adaptation of each osteosynthesis implant to the virtually reduced pelvis.

Modeling of unstable pelvic fractures for 20 ° sagittally rotated pelvic displacement

Early and accurate assessment of unstable pelvic fractures decreases mortality and morbidity by improving the outcomes of closed reduction surgery. In some circumstances (such as in developing countries or in acute trauma), accurate computed tomography (CT) 3D reconstructions are difficult to obtain and plain radiography must be relied upon for surgical planning. Therefore, a simulation model of pelvic displacement was evaluated as a basis for improving the assessment of pelvic fracture displacement from plain radiography images. The simulated model was based on a modified anteroposterior (AP) view of the pelvis constructed using anatomical data. Plain radiography imaging data of sagittal 20 ° hemipelvic rotation, similar to that observed in trauma, was obtained from the simulated model and were compared with normal pelvic rings from 10 cadaveric specimens (actual model). For each data set, the anterior superior iliac spine and ipsilateral pubic symphysis were measured on both sides. There was no significant difference between pelvic sides in the simulated and actual models (P = 0.870). Furthermore, no significant difference was found between the rotational degree of each pelvis based on calculated or simulated degrees and the 20 ° rotational angle (P = 0.322). A simulation model based on plain radiography of pelvic displacement could contribute to the optimal surgical management of unstable pelvic fractures without relying on CT.

Meta-analysis of locking plate versus intramedullary nail for treatment of proximal humeral fractures

Purpose

This meta-analysis compared the clinical outcomes of locking plate with intramedullary nail in the treatment of displaced proximal humeral fractures.

Methods

We searched PubMed, Embase, and the Cochrane databases for studies comparing locking plate and intramedullary nail treatment of displaced two-, three-, or four-part proximal humeral fractures. The quality of the studies was assessed, and meta-analysis was performed using the Cochrane Collaboration’s REVMAN 5.1 software.

Results

A total of 615 patients from eight studies were included in this meta-analysis (348 fractures treated with locking plate and 267 with intramedullary nail). Similar Constant scores were observed between the locking plate and intramedullary nail both in randomized controlled trials (RCTs) (mean difference (MD) = 2.12, 95 % confidence interval (CI), −2.54 to 6.79, P = 0.37) and observational studies (MD = −1.93, 95 % CI, −4.95 to 1.09, P = 0.21). Only one RCT provided American Shoulder and Elbow Surgeons Standardized scores indicating that the locking plate was better than the intramedullary nail (MD = 7.20, 95 % CI, 1.29–13.11, P = 0.02). The total complication rate did not specifically favor the locking plate or intramedullary nail both in the RCTs (risk ratio (RR), 2.44; 95 % CI, 0.35–16.78; P = 0.37) and observational studies (RR, 1.01; 95 % CI, 0.72–1.43; P = 0.94).

Conclusions

In the existing literature, limited evidence suggests that the locking plate and intramedullary nail are both valuable options for the treatment of proximal humeral fractures. Because of the observed heterogeneity and variance between the subgroups, more RCT are needed to be able to definitively recommend a locking plate or intramedullary nail for specific fracture patterns.

Does autogenous bone graft work? A logistic regression analysis of data from 159 papers in the foot and ankle literature

BACKGROUND

While autogenous cancellous iliac crest bone graft is the gold standard for foot and ankle surgery, it lacks Level I evidence. Although one third of all graft cases performed in the United States today rely on allograft, some surgeons believe no graft is necessary. We hypothesized that a systematic review of the foot and ankle literature would reveal that (1) autogenous bone graft during foot and ankle arthrodesis would demonstrate healing rates that were superior to the use of either using allograft or no bone graft at all, and (2) these differences would be even more dramatic in patients having risk factors that impair bone healing. To our knowledge, neither of these assessments to date has ever been performed with this body of literature. The goal of this study was to review the use and union rates of bone graft during foot and ankle arthrodesis and determine if autogenous bone graft was superior.

METHODS

A literature search was performed to include articles between 1959 and 2012 using autograft, allograft, and/or no bone graft for foot and/or ankle arthrodesis. Case reports involving fewer than four patients, investigations failing to incorporate outcome data, those involving orthobiologic augmentation, and those including vascularized graft, xenograft, or pediatric patients were excluded. Recorded search results included patient demographics, comorbidities, pre-operative diagnosis, surgical procedure, bone graft type and indication, union rate, method of fixation, patient satisfaction, all outcome scores, definition of healing/success, and any listed complications including revision. Final data were stratified based upon the type of graft material.

RESULTS

This search generated 953 related articles, of which 159 studies (5327 patients) met inclusion criteria. The majority (153/159) were retrospective case series. Systematic review demonstrated a trend toward higher union rates for cancellous autograft (OR 1.39, p=0.11), structural autograft (OR 1.52, p=0.09), and cancellous allograft (OR 1.31, p=0.52) relative to no graft material, but none reached statistical significance. Compared to no graft, structural allograft trended toward worse performance (OR 0.62, p=0.17). The overall probability of union was 93.7% for cancellous autograft, 94.2% for structural autograft, 93.3% for cancellous allograft, 91.4% for no graft, and 86.9% for structural allograft. When only comparing the 19 papers that included a no graft arm (91.9% union rate), data revealed the highest union using cancellous autograft (95.1%, OR 1.73, p=0.09) and structural autograft (96.3%, OR 2.33, p=0.06) while only 76% for structural allograft. No significant statistical association existed between union rates and other recorded variables.

CONCLUSION

Systematic analysis of bone graft use in foot and ankle fusions favors the use of autograft and cancellous allograft for optimized healing rates, although no differences were statistically significant. If we assume that graft material been chosen for more complex procedures having lower anticipated union rates, then these data lend further support to the use of autograft and cancellous allograft.

LEVEL OF EVIDENCE

Level IV.

Surgical Correction of Pelvic Malunion and Nonunion

Regardless of the method of treatment, as many as 5% of all pelvic fractures result in malunion or nonunion of the pelvis. However, there is not much information in the literature on the management of these late complications. Because they cause disabling symptoms and socioeconomic problems, some patients with malunion or nonunion of pelvic fractures need to undergo surgery. We report our experience with satisfactory results of surgery for pelvic malunion and nonunion in four patients. The key to successful reconstruction is thorough preoperative planning and methodical surgical intervention.

Nonunions and malunions of the pelvis

INTRODUCTION

Neglected pelvic fractures manifesting as pelvic nonunion or malunion are usually due to inadequate initial fixation or negligence of the injury because of increased attention towards other associated life-threatening conditions. The management of such injuries is complex. A systematic review was conducted to spot the clinical manifestations, evaluation, management and outcome of pelvic nonunion and malunion.

MATERIALS AND METHODS

Two databases ("Pubmed" and "Google scholar") were searched to look for relevant literature on pelvic non-union and malunion.  The search was limited to 'English language' and 'Human being'.

RESULTS

A total of 500 articles found, of which 10 articles were only reviewed which met the inclusion criteria. These articles discussed the clinical management and treatment of pelvic malunion and non-union following trauma without associated acetabular injury.

CONCLUSION

The usual presentations of pelvic non-union and malunion are pain, deformity, gait abnormality or instability. A detailed preoperative evaluation is essential as a majority of them have associated hip and spine injury which may be the cause of symptoms. Radiographs and 3D CT scans have helped surgeons in deciding the best way of management. The surgeries are usually complex and may need multiple-staged procedures. Soft tissue release, multiple osteotomies to achieve anatomical or near-anatomical reduction, augmentation of healing process using bone graft and stabilizing the nonunion/ osteotomy site using plates/screws/rods is the basic principle of surgery. Per-operative use of somato-sensory evoked potential evaluation helps the surgeon in preventing iatrogenic nerve injury. Despite these precautions and surgeries, most of the patients do not regain their preinjury functional activity.

Economic and social impact of upper extremity fragility fractures in elderly patients

BACKGROUND

Fragility fractures of the proximal humerus and distal radius can have a significant impact on the elderly population, both economically and physically. Limited data are available to demonstrate the functional and economic impact of upper extremity fragility fractures.

AIMS

To investigate the economic and social impact that proximal humerus fragility fractures may have on an older population.

METHODS

A retrospective chart review for patients ≥50 years old treated as an inpatient at a local hospital between 2006 and 2012 for a proximal humerus or a distal radius fracture was done. Patients were divided into two groups to show age impact; Group 1 = 50-79 years old and Group 2 = 80 years and older. Eighty-six charts were reviewed, 38 for Group 1 and 48 for Group 2. Demographic, admission, inpatient, and discharge data were compared between groups.

RESULTS

A third of patients in each group had a previous fragility fracture. Inpatient length of stay was comparable between groups. Surgical treatment was used at a higher rate in the younger cohort (p = 0.06). Approximate average hospital charges for an inpatient surgical treatment were about twice those of the non-surgically treated patients.

DISCUSSION

Our results illustrate the significant burden of upper extremity fractures in terms of loss of independence, inpatient hospitalizations and prolonged nursing home or rehabilitation needs, which account for considerable health care costs.

CONCLUSION

Fractures of the humerus, forearm and wrist account for one-third of the total incidence of fractures and can be a significant burden to individuals and the community.

Treatment of proximal humerus fractures with a CFR-PEEK plate: 2-year results of a prospective study and comparison to fixation with a conventional locking plate

BACKGROUND

A radiolucent carbon fiber-reinforced polyetheretherketone (CFR-PEEK) plate was recently introduced for fixation of proximal humerus fractures. Prospective clinical and radiographic results of patients treated with a CFR-PEEK plate are compared with those of patients treated with a conventional locking plate.

METHODS

Twenty-nine patients (mean age, 66 years) were treated with a CFR-PEEK plate for a 3- or 4-part proximal humerus fracture. Patients were clinically and radiographically re-examined at 6 weeks, 6 months, 12 months, and 24 months with the Simple Shoulder Test, Constant-Murley score (CMS), and Oxford Shoulder Score (OSS) as well as with simple radiographs. In addition, results were compared with a matched group of patients treated with a conventional locking plate.

RESULTS

At the final follow-up examination at 24 months, patients achieved a mean Simple Shoulder Test score of 58%, a mean CMS of 71.3 points (range, 44-97), and a mean OSS of 27.4 points (range, 8-45). Bone union was confirmed in all patients. Compared with patients treated with the conventional locking plate, patients treated with the CFR-PEEK plate achieved significantly better results with regard to the CMS and the OSS (P = .038 and .029, respectively). Furthermore, loss of reduction with subsequent varus deformity was less frequently observed in the CFR-PEEK plate group.

CONCLUSION

Fixation of proximal humerus fractures with a CFR-PEEK plate provides satisfying clinical and radiographic results after 2 years of follow-up. The results are comparable to those achieved with conventional locking plates.

Minimally invasive plate osteosynthesis for proximal humeral fractures

PURPOSE

To report the outcome after minimally invasive plate osteosynthesis (MIPO) through the deltoid-splitting approach for proximal humeral fractures.

METHODS

10 men and 30 women aged 37 to 88 years underwent MIPO through the deltoid-splitting approach using the Proximal Humerus Internal Locking System or the Locking Proximal Humerus Plate for 2-part (n=18), 3-part (n=20), and 4-part (n=2) proximal humeral fractures. The rehabilitation protocol was standardised.

RESULTS

All 40 patients were followed up at 3 months, 34 (85%) at 6 months, 30 (75%) at one year, and 13 (33%) at 2 years. Two patients had malunion. No patient had avascular necrosis, infection, nerve palsy, or nonunion. The mean Constant score at one year and 2 years was 75 and 87.5, respectively. The Constant score at 6 months correlated to that at one year (r=0.926, p<0.0001) and at 2 years (r=0.874, p=0.0001). In younger patients, improvement in the range of motion was faster. The early plateau group (those with no further improvement after 6 months) and the late plateau group (those with no further improvement after one year) did not differ significantly in age, fracture grade, or hand dominance.

CONCLUSION

MIPO for fixation of proximal humeral fractures using a locking plate is safe and effective in enabling an early return of shoulder function.

Bone augmentation using a new injectable bone graft substitute by combining calcium phosphate and bisphosphonate as composite--an animal model

Objective

The aim of this study was to create a new injectable bone graft substitute by combining the features of calcium phosphate and bisphosphonate as a composite bone graft to support bone healing and to evaluate the effect of alendronate to the bone healing process in an animal model.

Material and method

In this study, 24 New Zealand white rabbits were randomly divided into two groups: a calcium phosphate alendronate group and a calcium phosphate control group. A defect was created at the proximal medial tibia and filled with the new created injectable bone graft substitute calcium phosphate alendronate or with calcium phosphate. Healing process was documented by fluoroscopy. To evaluate the potential of the bone graft substitute, the proximal tibia was harvested 2, 4, and 12 weeks after operation. Histomorphological analysis was focused on the evaluation of the dynamic bone parameters using the Osteomeasure system.

Results

Radiologically, the bone graft materials were equally absorbed. No fracture was documented. The bones healed normally. After 2 weeks, the histological analysis showed an increased new bone formation for both materials. The osteoid volume per bone volume (OV/BV) was significantly higher for the calcium phosphate group. After 4 weeks, the results were almost equal. The trabecular thickness (Tb.Th) increased in comparison to week 2 in both groups with a slight advantage for the calcium phosphate group. The total mass of the bone graft (KEM.Ar) and the bone graft substitute surface density (KEM.Pm) were consistently decreasing. After 12 weeks, the new bone volume per tissue volume (BV/TV) was still constantly growing. Both bone grafts show a good integration. New bone was formed on the surface of both bone grafts. The calcium phosphate as well as the calcium phosphate alendronate paste had been enclosed by the bone. The trabecular thickness was higher in both groups compared to the first time point.

Conclusion

Calcium phosphate proved its good potential as a bone graft substitute. Initially, the diagrams seem to show a tendency that alendronate improves the known properties of calcium phosphate as a bone graft substitute. The composite graft induced a good and constant new bone formation. Not only the graft was incorporated into the bone but also a new bone was formed on its surface. But we could not prove a significant difference between the grafts. Both implants proved their function as a bone graft substitute, but the bisphosphonate alendronate does not support the bone healing process sufficiently that the known properties of calcium phosphate as a bone graft substitute were improved in the sense of a composite graft. In this study, alendronate used as a bone graft in a healthy bony environment did not influence the bone healing process in a positive or negative way.

Fast degradable citrate-based bone scaffold promotes spinal fusion

It is well known that high rates of fusion failure and pseudoarthrosis development (5~35%) are concomitant in spinal fusion surgery, which was ascribed to the shortage of suitable materials for bone regeneration. Citrate was recently recognized to play an indispensable role in enhancing osteconductivity and osteoinductivity, and promoting bone formation. To address the material challenges in spinal fusion surgery, we have synthesized mechanically robust and fast degrading citrate-based polymers by incorporating N-methyldiethanolamine (MDEA) into clickable poly(1, 8-octanediol citrates) (POC-click), referred to as POC-M-click. The obtained POC-M-click were fabricated into POC-M-click-HA matchstick scaffolds by compositing with hydroxyapatite (HA) for interbody spinal fusion in a rabbit model. Spinal fusion was analyzed by radiography, manual palpation, biomechanical testing, and histological evaluation. At 4 and 8 weeks post surgery, POC-M-click-HA scaffolds presented optimal degradation rates that facilitated faster new bone formation and higher spinal fusion rates (11.2±3.7, 80±4.5 at week 4 and 8, respectively) than the poly(L-lactic acid)-HA (PLLA-HA) control group (9.3±2.4 and 71.1±4.4) (p<0.05). The POC-M-click-HA scaffold-fused vertebrates possessed a maximum load and stiffness of 880.8±14.5 N and 843.2±22.4 N/mm, respectively, which were also much higher than those of the PLLA-HA group (maximum: 712.0±37.5 N, stiffness: 622.5±28.4 N/mm, p<0.05). Overall, the results suggest that POC-M-click-HA scaffolds could potentially serve as promising bone grafts for spinal fusion applications.

How to enhance the stability of locking plate fixation of proximal humerus fractures? An overview of current biomechanical and clinical data

BACKGROUND

The complication rate after locking plate fixation of proximal humerus fractures is high. In addition to low bone mineral density, a lack of medial support has been identified as one of the most important factors accounting for mechanical instability. As a result of the high failure rate, different strategies have been developed to enhance the mechanical stability of locking plate fixation of proximal humerus fractures. The aim of the present article is to give an overview of the current biomechanical and clinical studies that focus on how to increase the stability of locking plate fixation of proximal humerus fractures.

METHODS

A comprehensive search of the Medline databases using specific search terms with regard to the stability of locking plate fixation of proximal humerus fractures was performed. After screening of the articles for eligibility, they were subdivided according to clinical and biomechanical aspects.

RESULTS

Medial support screws, filling of bone voids and screw-tip augmentation with bone cement as well as the application of bone grafts are currently the most frequently assessed and performed methods. Although the evidence is weak, all of the mentioned strategies appear to have a positive effect on achieving and maintaining a stable reduction even of complex fractures.

CONCLUSION

Further clinical studies with a higher number of patients and a higher level of evidence are required to develop a standardised treatment algorithm with regard to cement augmentation and bone grafting. Although these measures are likely to have a stabilising effect on locking plate fixation, its general use cannot be fully recommended yet.

Comparison of therapeutic effects of anterior decompression and posterior decompression on thoracolumbar spine fracture complicated with spinal nerve injury

Objective:

To compare the clinical therapeutic effects of anterior decompression and posterior decompression on thoracolumbar spine fracture (TSF) complicated with spinal nerve injury (SNI).

Methods:

A total of 120 patients with TSF and SNI were selected and divided into a treatment group and a control group that were then treated by anterior decompression and posterior decompression respectively. The preoperative and postoperative motor scores, tactile scores, heights of injured vertebral body and Cobb’s angles, as well as surgical times and intraoperative blood losses were recorded and compared.

Results:

Before surgeries, the motor score, tactile score, height of injured vertebral body and Cobb’s angle of the treatment group were similar to those of the control group (P>0.05). After surgeries, the values of the treatment group were significantly different from those of the control group (P<0.05). The two groups also had significantly different intraoperative blood losses and surgical times (P<0.05).

Conclusion:

Compared with posterior decompression, anterior decompression improved spinal cord function better and relived spinal cord compression more effectively with a more reasonable mechanics of internal fixation. Although this protocol caused more blood loss, the overall therapeutic effects were more satisfactory.

Fracture non-union epidemiology and treatment

Fracture non-union remains a clinical problem despite advances in the understanding of basic science and technology. Each fracture has a unique personality as does the patient suffering the injury. Thus, each case must be treated on an individual basis. This article defines the problem of fracture non-union and reports recent epidemiological studies. We discuss relevant risk factors and methods for assessing patients who have a tendency toward fracture non-union. There are many treatment options for patients with non-union, where a number of these modalities are still under review. We discuss current evidence with the use of bone morphogenic protein, platelet-rich plasma and low-intensity pulsed ultrasound to augment the treatment of fracture non-union.

Fatal necrotizing fasciitis due to necrotic toxin-producing Escherichia coli strain

We report a fatal case of necrotizing soft tissues infection caused by an Escherichia coli strain belonging to phylogenetic group C and harbouring numerous virulence factors reported to be part of a pathogenicity island (PAI) such as PAI II_J96 and conserved virulence plasmidic region.

High-dose recombinant human bone morphogenetic protein-2 impacts histological and biomechanical properties of a cervical spine fusion segment: results from a sheep model

The 'off-label' use of high-dose recombinant human bone morphogenetic protein-2 (rhBMP-2) in lumbar and cervical fusion leads to heterotopic bone formation and vertebral osteolysis. These radiographically assessed side-effects in patients were frequently associated with an over-dosage of BMP-2. However, little is so far known about the histological, functional or biomechanical tissue consequences of over-dosage of rhBMP-2 in these specific clinical situations. We hypothesized that a high dose of rhBMP-2 in cervical spinal fusion could induce substantial alterations in bone, leading to mechanical impairment. An anterior cervical spinal fusion (C3-C4 ACDF) model in 16 sheep (aged > 2.5 years; n = 8/group) was used to quantify the consequences of a high rhBMP-2 dose (6 mg rhBMP-2) on fusion tissue compared to the 'gold standard' of autologous, cancellous bone graft. The fusion site was assessed by radiography after 0, 8 and 12 weeks. Biomechanical non-destructive testing and (immuno)histological and histomorphometrical analyses were performed 12 weeks postoperatively. Although high-dose rhBMP-2 treatment led to an advanced radiological fusion result compared to autograft treatment, heterotopic bone formation and vertebral bone resorption were induced simultaneously. Histological evaluation unveiled highly active bone-forming processes ventral to the fusion segment after 12 weeks, while radiolucent areas showed still a partial loss of regular trabecular structure, with rare signs of remodelling and restoration. Despite qualitative alteration of the trabecular bone structure within the fusion site, the massive anterior heterotopic bone formation led to a substantial increase in mechanical stiffness compared to the autograft group. Copyright © 2015 John Wiley & Sons, Ltd.

Decoupling the role of stiffness from other hydroxyapatite signalling cues in periosteal derived stem cell differentiation

Bone extracellular matrix (ECM) is a natural composite made of collagen and mineral hydroxyapatite (HA). Dynamic cell-ECM interactions play a critical role in regulating cell differentiation and function. Understanding the principal ECM cues promoting osteogenic differentiation would be pivotal for both bone tissue engineering and regenerative medicine. Altering the mineral content generally modifies the stiffness as well as other physicochemical cues provided by composite materials, complicating the “cause-effect” analysis of resultant cell behaviour. To isolate the contribution of mechanical cues from other HA-derived signals, we developed and characterised composite HA/gelatin scaffolds with different mineral contents along with a set of stiffness-matched HA-free gelatin scaffolds. Samples were seeded with human periosteal derived progenitor cells (PDPCs) and cultured over 7 days, analysing their resultant morphology and gene expression. Our results show that both stiffness and HA contribute to directing PDPC osteogenic differentiation, highlighting the role of stiffness in triggering the expression of osteogenic genes and of HA in accelerating the process, particularly at high concentrations.

Toward smart implant synthesis: bonding bioceramics of different resorbability to match bone growth rates

Craniofacial reconstructive surgery requires a bioactive bone implant capable to provide a gradual resorbability and to adjust to the kinetics of new bone formation during healing. Biomaterials made of calcium phosphate or bioactive glasses are currently available, mainly as bone defect fillers, but it is still required a versatile processing technique to fabricate composition-gradient bioceramics for application as controlled resorption implants. Here it is reported the application of rapid prototyping based on laser cladding to produce three-dimensional bioceramic implants comprising of a calcium phosphate inner core, with moderate in vitro degradation at physiological pH, surrounded by a bioactive glass outer layer of higher degradability. Each component of the implant is validated in terms of chemical and physical properties, and absence of toxicity. Pre-osteoblastic cell adhesion and proliferation assays reveal the adherence and growth of new bone cells on the material. This technique affords implants with gradual-resorbability for restoration of low-load-bearing bone.

Geriatric proximal humeral fracture patients show similar clinical outcomes to non-geriatric patients after osteosynthesis with endosteal fibular strut allograft augmentation

BACKGROUND

Osteosynthesis of proximal humeral fractures is challenging in geriatric patients. The purpose of this investigation was to compare postoperative clinical outcomes between cohorts of geriatric (aged ≥65 years) and non-geriatric proximal humeral fracture patients treated via locked plating with endosteal fibular strut allograft augmentation.

METHODS

From March 2007 to January 2013, 71 adult patients with 2-, 3-, and 4-part proximal humeral fractures according to the Neer classification underwent osteosynthesis with locked plating and fibular allograft augmentation and had at least 12 months of clinical follow-up. All patients followed the same postoperative rehabilitation protocol. We compared the following between geriatric and non-geriatric patients: Disabilities of the Arm, Shoulder and Hand scores; University of California, Los Angeles shoulder ratings; Constant-Murley scores; and range of motion; as well as injury characteristics and radiographic outcomes.

RESULTS

Geriatric patients comprised 48% of the study cohort (34 of 71 patients). The mean age of the geriatric and non-geriatric cohorts was 74 years and 53 years, respectively. Geriatric patients showed significantly reduced forward flexion (147° vs 159°, P = .04) when compared with non-geriatric patients. There were no significant differences in functional scores, radiographic outcomes, or complication rates between the 2 cohorts, although in 1 geriatric patient, osteonecrosis developed and screw penetration through the collapsed head was present 3 years after surgery.

CONCLUSIONS

Osteosynthesis of proximal humeral fractures via locked plating with fibular strut allograft augmentation results in similar clinical outcomes between geriatric and non-geriatric patients. We believe that enhanced stability provided by this fixation construct allows early intensive postoperative therapy and results in excellent outcomes despite patient age.

Factors that Influence Reduction Loss in Proximal Humerus Fracture Surgery

OBJECTIVES

This study was performed to identify the risk factors for reduction loss after locking plate fixation of proximal humerus fractures.

DESIGN

Retrospective study.

SETTING

University trauma center.

PATIENTS AND INTERVENTION

We retrospectively evaluated 252 patients who had been surgically treated for proximal humeral fractures with locking plates between January 2004 and December 2011.

MAIN OUTCOME MEASUREMENTS

Charts and standardized x-rays (true anteroposterior and axillary lateral views) were used to evaluate the Neer and AO OTA fracture types, initial neck-shaft angle (NSA, varus displacement), medial comminution, postoperative NSA (reduction adequacy), medial support restoration, healing progress, reduction loss, and implant-related problems immediately after surgery and at 2 weeks, 1 month, 3 months, 6 months, 9 months, and at least 1 year after surgery. Reduction loss was defined as (1) ≥10 of angulation in any direction, (2) ≥5 mm of height loss of the humeral head from the plate, and (3) fixation failure.

RESULTS

Reduction loss occurred in 6.7% (17 of 252) of cases; revision surgeries were performed in all cases. Univariable logistic regression analysis revealed that older age (P = 0.023), osteoporosis (P = 0.001), varus displacement (P = 0.001), medial comminution (P = 0.001), reduction adequacy (P = 0.036), and insufficient medial support (P = 0.001) had significant correlations with reduction loss.

CONCLUSIONS

Multivariable regression analysis revealed that osteoporosis (less than -2.5 bone mineral density, P = 0.015), displaced varus fracture (less than 110° of NSA, P = 0.025), medial comminution (more than 1 fragment, P = 0.018), and insufficient medial support (no cortical or screw support, P = 0.001) were independent risk factors for reduction loss in the proximal humerus fractures surgery.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Fabrication method, structure, mechanical, and biological properties of decellularized extracellular matrix for replacement of wide bone tissue defects

The present paper was focused on the development of a new method of decellularized extracellular matrix (DECM) fabrication via a chemical treatment of a native bone tissue. Particular attention was paid to the influence of chemical treatment on the mechanical properties of native bones, sterility, and biological performance in vivo using the syngeneic heterotopic and orthotopic implantation models. The obtained data indicated that after a chemical decellularization treatment in 4% aqueous sodium chlorite, no noticeable signs of the erosion of compact cortical bone surface or destruction of trabeculae of spongy bone in spinal channel were observed. The histological studies showed that the chemical treatment resulted in the decellularization of both bone and cartilage tissues. The DECM samples demonstrated no signs of chemical and biological degradation in vivo. Thorough structural characterization revealed that after decellularization, the mineral frame retained its integrity with the organic phase; however clotting and destruction of organic molecules and fibers were observed. FTIR studies revealed several structural changes associated with the destruction of organic molecules, although all organic components typical of intact bone were preserved. The decellularization-induced structural changes in the collagen constituent resulted changed the deformation under compression mechanism: from the major fracture by crack propagation throughout the sample to the predominantly brittle fracture. Although the mechanical properties of radius bones subjected to decellularization were observed to degrade, the mechanical properties of ulna bones in compression and humerus bones in bending remained unchanged. The compressive strength of both the intact and decellularized ulna bones was 125-130 MPa and the flexural strength of humerus bones was 156 and 145 MPa for the intact and decellularized samples, respectively. These results open new avenues for the use of DECM samples as the replacement of wide bone tissue defects.

Proximal humeral fracture fixation: multicenter study with carbon fiber peek plate

BACKGROUND

Locking plate fixation is a reliable treatment for many displaced proximal humeral fractures. Carbon fiber-reinforced-poly-ether-ether-ketone (CFR-PEEK) plates have recently been introduced as an alternative to traditional metallic plates.

METHODS

In a multicenter study involving the Orthopedic Services of 6 Italian hospitals, 182 patients with a proximal humeral fracture were treated with a Diphos H (Lima Corporate, San Daniele del Friuli, Italy) CFR-PEEK plate, 160 of whom were followed clinically and radiographically for 2 years or more. Fractures were classified by Neer's system. The functional results were assessed by Constant and DASH scores.

RESULTS

The average time to radiographic healing was 5.6 months in 158 of 160 cases. Mean Constant score was 76, and mean DASH score was 28 at 2 years. There were two nonunions (one septic and one aseptic) and 13 cases of partial (9) or massive (4) humeral head necrosis. In three of the 78 patients treated with the first-generation plates, hardware breakage happened during the operation and the plate was replaced. There was no failure among the cases treated with the thicker second-generation plate. In eight cases, there was a perforation of the humeral head by the cephalic screws.

CONCLUSIONS

CFR-PEEK plates proved as reliable as metallic plates in the treatment of proximal humeral fractures. The advantages of these new devices include a better visualization of fracture reduction during intraoperative fluoroscopic assessment and easy hardware removal due to the absence of screw-plate cold fusion.

Bone regeneration and gene expression in bone defects under healthy and osteoporotic bone conditions using two commercially available bone graft substitutes

Biosilicate(®) and Bio-Oss(®) are two commercially available bone substitutes, however, little is known regarding their efficacy in osteoporotic conditions. The purpose of this study was to evaluate the osteogenic properties of both materials, at tissue and molecular level. Thirty-six Wistar rats were submitted to ovariectomy (OVX) for inducing osteoporotic conditions and sham surgery (SHAM) as a control. Bone defects were created in both femurs, which were filled with Biosilicate(®) or Bio-Oss(®), and empty defects were used as control. For the healthy condition both Biosilicate(®) and Bio-Oss(®) did not improve bone formation after 4 weeks. Histomorphometric evaluation of osteoporotic bone defects with bone substitutes showed more bone formation, significant for Bio-Oss(®). Molecular biological evaluation was performed by gene-expression analysis (Runx-2, ALP, OC, OPG, RANKL). The relative gene expression was increased with Biosilicate(®) for all genes in OVX rats and for Runx-2, ALP, OC and RANKL in SHAM rats. In contrast, with Bio-Oss(®), the relative gene expression of OVX rats was similar for all three groups. For SHAM rats it was increased for Runx-2, ALP, OC and RANKL. Since both materials improved bone regeneration in osteoporotic conditions, our results suggest that bone defects in osteoporotic conditions can be efficiently treated with these two bone substitutes.

Comparison of structural allograft and traditional autograft technique in occipitocervical fusion: radiological and clinical outcomes from a single institution

OBJECT The authors' objectives were to compare the rate of fusion after occipitoatlantoaxial arthrodesis using structural allograft with the fusion rate from using autograft, to evaluate correction of radiographic parameters, and to describe symptom relief with each graft technique. METHODS The authors assessed radiological fusion at 6 and 12 months after surgery and obtained radiographic measurements of C1-2 and C2-7 lordotic angles, C2-7 sagittal vertical alignments, and posterior occipitocervical angles at preoperative, postoperative, and final follow-up examinations. Demographic data, intraoperative details, adverse events, and functional outcomes were collected from hospitalization records. Radiological fusion was defined as the presence of bone trabeculation and no movement between the graft and the occiput or C-2 on routine flexion-extension cervical radiographs. Radiographic measurements were obtained from lateral standing radiographs with patients in the neutral position. RESULTS At the University of Utah, 28 adult patients underwent occipitoatlantoaxial arthrodesis between 2003 and 2010 using bicortical allograft, and 11 patients were treated using iliac crest autograft. Mean follow-up for all patients was 20 months (range 1-108 months). Of the 27 patients with a minimum of 12 months of follow-up, 18 (95%) of 19 in the allograft group and 8 (100%) of 8 in the autograft group demonstrated evidence of bony fusion shown by imaging. Patients in both groups demonstrated minimal deterioration of sagittal vertical alignment at final follow-up. Operative times were comparable, but patients undergoing occipitocervical fusion with autograft demonstrated greater blood loss (316 ml vs 195 ml). One (9%) of 11 patients suffered a significant complication related to autograft harvesting. CONCLUSIONS The use of allograft in occipitocervical fusion allows a high rate of successful arthrodesis yet avoids the potentially significant morbidity and pain associated with autograft harvesting. The safety and effectiveness profile is comparable with previously published rates for posterior C1-2 fusion using allograft.