Does Teriparatide Improve Fracture Union?: A Systematic Review

Results of a simple treatment protocol for aseptic femoral shaft nonunion in 330 patients

INTRODUCTION

Our primary aim of the study was to assess the results of a treatment protocol for aseptic femoral shaft nonunion treated by three techniques - Exchange Nailing (EN), Plate Augmentation (PA), and Exchange Nailing combined with Plate augmentation (NP). The secondary objective was to assess the radiological outcome, duration of surgery (DOS) and need for blood transfusion (BT) in all the three groups.

MATERIALS AND METHODS

We analyzed 330 patients treated for AFNU between Jan 2007 and Dec 2019. Using a simple treatment algorithm, EN, PA and NP were performed in 24,183 and 123 patients respectively. Patients in all the three groups were assessed for radiological-union (union rate and time to union), DOS and BT.

RESULTS

Of these 330 patients, 327 (99 %) patients achieved radiological union at a mean duration of 6.07 months. Union rate is highest with NP followed by PA and EN. The union rate in patients with NP, PA and EN were 100 %, 99.5 % and 91.7 % respectively (p < 0.01). Time to union was lowest for NP followed by PA and EN (p < 0.001).The mean time to union for NP, PA and EN were 3.76, 7.2and 9.21 months respectively (p < 0.001). The mean DOS in minutes for NP, EN and PA was 107, 94 and 82 respectively (p < 0.01). The mean need for BT in the form of packed red blood cells for NP, PA and EN were 1.95, 1.87 and 1.38 units respectively (p < 0.01).

CONCLUSION

Following a simple algorithm to decide treatment protocol on a case-to case basis helps to achieve good results in an optimal time period. When compared with EN and PA, NP is associated with 100 % union rate with least time to union making NP a reasonably effective procedure with a very high success rate.

LEVEL OF EVIDENCE

IV.

Open Reduction and Internal Fixation for Vancouver B1 and B2 Periprosthetic Femoral Fractures: A Proportional Meta-Analysis

Purpose

Periprosthetic femoral fracture (PFF) is a common complication after total hip arthroplasty, and open reduction and internal fixation (ORIF) is a common surgical treatment. We conducted a meta-analysis to compare the outcomes of ORIF in patients with different fracture patterns (Vancouver B1 and B2).

Materials and Methods

We conducted a systematic search of PubMed, Embase, Cochrane Library and KoreaMed from inception to August 2022. We conducted a pair-wise meta-analysis (with a fixed-effects model) on the 10 comparative studies and a proportional meta-analysis on the data from the 39 articles to determine a consensus. The outcomes were the incidence of reoperations that included osteosynthesis, irrigation/debridement and revision arthroplasty.

Results

The pair-wise meta-analysis showed similar outcomes between two groups; the risk of reoperation (odds ratio [OR]=0.82, confidence interval [CI] 0.43-1.55, P=0.542), nonunion (OR=0.49; CI 0.22-1.10, P=0.085) and deep infection (OR=1.89, CI 0.48-7.46, P=0.361). In proportion meta-analysis, pooled prevalence of reoperation was 9% (95% CI, 6-12) in B1 and 8% (95% CI, 2-15) in B2 (heterogeneity between two groups (Q), P=0.772). The pooled prevalence of nonunion was same as of 4% in B1 and B2 (Q, P=0.678), and deep infection was 2% (95% CI, 1-3) in B1 and 4% (95% CI, 2-7) in B2 (Q, P=0.130).

Conclusion

ORIF is a feasible treatment for B1 and B2 periprosthetic femoral fractures, with acceptable outcomes in terms of, nonunion and infection. The results of this study would help clinicians and provide baseline data for further studies validating PFF.

Application of Escherichia coli-Derived Recombinant Human Bone Morphogenic Protein-2 to Unstable Spinal Fractures

(1) Background: Recently, Escherichia coli-derived recombinant human bone morphogenetic protein-2 (E. coli-derived rhBMP-2) has been increasingly applied to different types of spinal surgeries and reported to achieve successful fusion. This pilot study aimed to evaluate the clinical efficacy and safety of rhBMP-2 in patients undergoing posterior instrumented fusions for unstable spinal fractures. (2) Methods: This study included ten consecutive patients undergoing spinal surgery using E. coli-derived rhBMP-2 with more than one year of follow-up. Radiologic outcomes were compared, including the average fracture healing period, local kyphosis correction, and clinical outcomes between preoperative and the last follow-up. (3) Results: The average time of radiographic union was 99.9 ± 45.4 (62-192) days, with an average use of 5.2 ± 3.9 months of anabolic agents. Radiologic parameters such as anterior vertebral height and vertebral wedge angle were significantly corrected postoperatively and at the last follow-up. Clinical outcomes other than leg pain were significantly improved after the surgery. In addition, four patients with preoperative neurologic deficits showed improved neurologic status. (4) Conclusions: Combined with the anabolic agents, applying E. coli-derived rhBMP-2 to the fractured vertebral body could be an effective surgical treatment for unstable spinal fractures. Further trials are needed to validate this result.

Position Statement: Atypical Femoral Fracture from the Korean Society for Bone and Mineral Research in 2023

As the aging population increases, the number of patients with osteoporosis is gradually rising. Osteoporosis is a metabolic bone disease characterized by low bone mass and the microarchitectural deterioration of bone tissue, resulting in reduced bone strength and an increased risk of low-energy or fragility fractures. Thus, the use of anti-resorptive agents, such as bisphosphonates (BPs), to prevent osteoporotic fractures is growing annually. BPs are effective in reducing hip and other fractures. However, the longer a patient takes BPs, the higher the risk of an atypical femoral fracture (AFF). The exact mechanism by which long-term BP use affects the development of AFFs has not yet been clarified. However, several theories have been suggested to explain the pathogenesis of AFFs, such as suppressed bone remodeling, impaired bone healing, altered bone quality, and femoral morphology. The management of AFFs requires both medical and surgical approaches. BPs therapy should be discontinued immediately, and calcium and vitamin D levels should be evaluated and supplemented if insufficient. Teriparatide can be used for AFFs. Intramedullary nailing is the primary treatment for complete AFFs, and prophylactic femoral nailing is recommended if signs of an impending fracture are detected.

Effect of Ishophloroglucin A Isolated from Ishige okamurae on In Vitro Osteoclastogenesis and Osteoblastogenesis

The balance between bone-resorbing osteoclasts and bone-forming osteoblasts is essential for the bone remodeling process. This study aimed to investigate the effect of Ishophloroglucin A (IPA) isolated from Ishige okamurae on the function of osteoclasts and osteoblasts in vitro. First, we demonstrated the effect of IPA on osteoclastogenesis in receptor activator of nuclear factor κB ligand (RANKL)-induced RAW 264.7 cells. IPA inhibited the tartrate-resistant acid phosphatase (TRAP) activity and osteoclast differentiation in RANKL-induced RAW 264.7 cells. Moreover, it inhibited the RANKL-induced osteoclast-related factors, such as TRAP, matrix metalloproteinase-9 (MMP-9), and calcitonin receptor (CTR), and transcription factors, such as nuclear factor of activated T cells 1 (NFATc1) and c-Fos. IPA significantly suppressed RANKL-activated extracellular signal-regulated kinase (ERK), and NF-κB in RAW 264.7 cells. Our data indicated that the ERK and NF-κB pathways were associated with the osteoclastogenesis inhibitory activity of IPA. Next, we demonstrated the effect of IPA on osteoblastogenesis in MG-63 cells. IPA significantly promoted alkaline phosphatase (ALP) activity in MG-63 cells, along with the osteoblast differentiation-related markers bone morphogenetic protein 2 (BMP2), type 1 collage (COL1), p-Smad1/5/8, and Runx2, by activating the MAPK signaling pathways. Taken together, the study indicated that IPA could be effective in treating bone diseases, such as osteoporosis.

The effect of teriparatide on fracture healing after atypical femoral fracture: A systematic review and meta-analysis

This meta-analysis demonstrated that a greater prevalence of delayed union and nonunion and a longer time to fracture healing in the group that did not receive TPTD treatment after AFFs than in the group that received TPTD treatment.

PURPOSE

To date, there is no hard evidence for medical management after atypical femoral fracture (AFF), even though weak data indicate faster healing with teriparatide (TPTD). Herein, we aimed to investigate the effect of postfracture TPTD treatment on AFF healing using a pairwise meta-analysis focusing on delayed union, nonunion, and fracture healing time.

METHODS

A systematic search of the MEDLINE (PUBMED), Embase, and Cochrane Library databases was performed for studies investigating the effect of TPTD after AFF up to October 11, 2022. We compared the incidence of delayed union and nonunion and the time of fracture healing between the TPTD ( +) and TPTD (-) groups.

RESULTS

The 6 studies analyzed a total of 214 AFF patients, including 93 who received TPTD therapy after AFF and 121 who did not. The pooled analysis showed a significantly higher rate of delayed union in the TPTD (-) group than in the TPTD ( +) group (OR, 0.24; 95% CI, 0.11-0.52; P < 0.01; I² = 0%), and a higher nonunion rate was observed in the TPTD (-) group than in the TPTD ( +) group with low heterogeneity (OR, 0.21; 95% CI, 0.06-0.78; P = 0.02; I² = 0%). The TPTD (-) group required 1.69 months longer to achieve fracture union than the TPTD ( +) group, with statistical significance (MD =  - 1.69, 95% CI: - 2.44 to - 0.95, P < 0.01; I² = 13%). Subgroup analysis for patients with complete AFF showed that the TPTD (-) group had a higher rate of delayed union with low heterogeneity (OR, 0.22; 95% CI, 0.10-0.51; P < 0.01; I² = 0%), but there was no significant difference in the nonunion rate between TPTD ( +) and TPTD (-) groups (OR, 0.35; 95% CI, 0.06-2.21; P = 0.25; I² = 0%). Fracture healing took significantly longer in the TPTD (-) group (MD =  - 1.81, 95% CI: - 2.55 to - 1.08; P < 0.01; I² = 48%). The reoperation rate showed no significant difference between the two groups (OR, 0.29; 95% CI, 0.07-1.20; P = 0.09; I² = 0%).

CONCLUSIONS

The current meta-analysis supported the hypothesis that TPTD treatment following AFF might benefit fracture healing, lowering the rate of delayed union and nonunion and shortening the fracture healing time.

Use of Teriparatide in preventing delayed bone healing and nonunion: a multicentric study on a series of 20 patients

BACKGROUND

Delayed bone healing and nonunions represent a great challenge for the orthopedic surgeon. In addition to traditional surgical approaches, increasing attention is being given to the use of systemic anabolic therapy with Teriparatide, whose efficacy in preventing osteoporotic fractures is widely validated and whose application as a promoter of bone healing has been described but it is still debated. The aim of the study was to evaluate bone healing in a series of patients with delayed unions or nonunions treated with Teriparatide in conjunction with eventual appropriate surgical procedure.

METHODS

Twenty patients with an unconsolidated fracture that were treated at our Institutions from 2011 to 2020 with Teriparatide were retrospectively included into the study. The pharmacological anabolic support was used off-label with a planned duration of 6 months; radiographic healing was evaluated at 1-, 3- and 6-months follow-up outpatient visits over plain radiographs. Also, eventual side-effects were registered.

RESULTS

Radiographic signs indicative of favorable evolution of the bone callus were observed as early as at 1 month of therapy in 15% of cases; at 3 months, healing progression was appreciated in 80% of cases and complete healing in 10%; at 6 months, 85% of delayed and nonunions had healed. In all patients, the anabolic therapy was well tolerated.

CONCLUSIONS

In accordance to Literature, this study suggests that Teriparatide plays a potentially important role in the treatment of some forms of delayed unions or nou-nions, even in the presence of failure of hardware. The results suggest a greater effect of the drug when associated with a condition in which the bone is in an active phase of callogenesis, or with a "revitalizing" treatment which represents a local (mechanical and/or biological) stimulus to the healing process. Despite the small sample size and the variety of cases, the efficacy of Teriparatide in treating delayed unions or nonunions emerged, highlighting how this anabolic therapy can represent a useful pharmacological support in the treatment of such a pathology. Although the results obtained are encouraging, further studies, particularly prospective and randomized, are needed to confirm the efficacy of the drug, and define a specific treatment algorithm.

Factors affecting healing and progression of conservatively treated incomplete atypical femoral fractures: retrospective observational study

INTRODUCTION

Incomplete atypical femoral fractures (iAFF) may occur with prolonged bisphosphonate usage. Factors influencing iAFF healing and progression are not well understood. This study of conservatively managed iAFF assessed factors influencing iAFF healing and progression including the effects of bisphosphonates and teriparatide use.

MATERIALS AND METHODS

Single-center retrospective observational study of 69 consecutive patients with 78 radiographically confirmed iAFF from 2002 to 2017. Serial radiographs assessed for focal cortical thickening, dreaded black line (DBL) and complete fracture. Chief outcome measures were DBL healing and complete fracture.

RESULTS

DBL had a significant association (p < 0.05) with fracture progression by multivariable logistic regression (55.8% versus 25.7%, odds ratio [OR] 26.57 (95% CI 1.40-504.78)) and shorter fracture-free survival (mean 3.21 versus 6.27 years). Presence of symptoms was associated with shorter fracture-free survival (mean 2.68 versus 5.98 years). Discontinuing bisphosphonates had significant associations (p < 0.001) by multivariable logistic regression with decreased fracture rate (11.6% versus 92.0%; OR 0.00, 95% CI 0.00-0.08) and longer fracture-free survival (mean 7.52 versus 1.99 years). DBL healing occurred in 36.4%, only when bisphosphonates were discontinued. Age, sex, race, fracture site, glucocorticoid use, teriparatide supplementation and duration of bisphosphonate use showed no statistically significant effect although teriparatide use appeared to improve DBL healing (50% versus 17.9%, p = 0.188).

CONCLUSIONS

In conservatively managed iAFF, DBL healing occurred in 36.4% if bisphosphonates were discontinued. Bisphosphonates and DBL were significantly associated with fracture progression and together with symptoms with fracture survival.

Osteoanabolic Treatment with Teriparatide for Pathological Stress Transfer After Total Hip Arthroplasty: A Case Report

CASE

Total hip arthroplasty with an uncemented, tapered, fluted stem was performed in a 79-year-old woman with known osteoporosis to treat an intertrochanteric fracture. Exertional thigh pain and cortical thickening developed at the tip of the stem. The patient was treated with teriparatide for a total of 2 years and became asymptomatic within months. Radiographs showed improved bone quality around the stem of the prosthesis, and dual-energy x-ray absorptiometry scans confirmed remineralization.

CONCLUSION

Stem tip pain is a well-known complication of distally engaging arthroplasty implants. Various surgical options have been suggested to address this condition. Teriparatide is known to help prevent fractures and improve bone healing. This successful off-label use might be of interest for the future treatment of this biomechanical complication.

The effect of osteoporosis and its treatment on fracture healing a systematic review of animal and clinical studies

Introduction

Osteoporosis is characterised by low bone mass and micro-architectural deterioration of bone structure. Its treatment is directed at the processes of bone formation or resorption, that are of utmost importance in fracture healing. We provide a comprehensive review of the literature aiming to summarize and clarify the effects of osteoporosis and its treatment on fracture healing.

Material and methods

A literature search was conducted in PubMed and Embase (OVID version). In vivo animal and human studies on long bone fractures were included. A total of 93 articles were included for this review; 23 studies on the effect of osteoporosis (18 animal and 5 clinical studies) and 70 studies on the effect of osteoporosis treatment (41 animal, 26 clinical studies and 3 meta-analyses) on fracture healing.

Results

In animal fracture models osteoporosis was associated with decreased callus formation and bone growth, bone mineral density, biomechanical strength and delayed cellular and differentiation processes during fracture healing. Two large databases identified osteoporosis as a risk factor for non-union whereas three other studies did not. One of those three studies however found a prolonged healing time in patients with osteoporosis. Anti-osteoporosis medication showed inconsistent effects on fracture healing in both non-osteoporotic and osteoporotic animal models. Only the parathyroid hormone and anti-resorption medication were related to improved fracture healing and delayed remodelling respectively. Clinical studies performed in predominantly hip and distal radius fracture patients showed no effect of bisphosphonates on fracture healing. Parathyroid hormone reduced time to union in several clinical trials performed in mainly hip fracture patients, but this did not result in decreased delayed or non-union rates.

Conclusion

Evidence that substantiates the negative influence of osteoporosis on fracture healing is predominantly from animal studies and to a lesser extent from clinical studies, since convincing clinical evidence lacks. Bisphosphonates and parathyroid hormone may be used during fracture healing, since no clear negative effect has been shown. Parathyroid hormone might even decrease time to fracture union, without decreasing union rate.

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Osteoporosis negatively influences fracture healing in animal models.

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There is no convincing evidence for a similar effect in humans.

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In animals, bisphosphonates delay bone remodelling

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In animals, parathyroid hormone improves fracture healing

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In humans, anti-osteoporotic drugs do not interfere with fracture healing.

Site-Specific Fracture Healing: Comparison between Diaphysis and Metaphysis in the Mouse Long Bone

The process of fracture healing varies depending upon internal and external factors, such as the fracture site, mode of injury, and mechanical environment. This review focuses on site-specific fracture healing, particularly diaphyseal and metaphyseal healing in mouse long bones. Diaphyseal fractures heal by forming the periosteal and medullary callus, whereas metaphyseal fractures heal by forming the medullary callus. Bone healing in ovariectomized mice is accompanied by a decrease in the medullary callus formation both in the diaphysis and metaphysis. Administration of estrogen after fracture significantly recovers the decrease in diaphyseal healing but fails to recover the metaphyseal healing. Thus, the two bones show different osteogenic potentials after fracture in ovariectomized mice. This difference may be attributed to the heterogeneity of the skeletal stem cells (SSCs)/osteoblast progenitors of the two bones. The Hox genes that specify the patterning of the mammalian skeleton during embryogenesis are upregulated during the diaphyseal healing. Hox genes positively regulate the differentiation of osteoblasts from SSCs in vitro. During bone grafting, the SSCs in the donor’s bone express Hox with adaptability in the heterologous bone. These novel functions of the Hox genes are discussed herein with reference to the site-specificity of fracture healing.

Molecular enhancement of fracture healing - Is there a role for Bone Morphogenetic Protein-2, parathyroid hormone, statins, or sclerostin-antibodies?

Enhancement of fracture healing has been a hot topic over the last two decades. This narrative review article is aimed to provide an update on current clinical use and evidence on four clinically available agents in the treatment of fracture healing: bone morphogenetic proteins-2 (BMP-2), parathyroid hormone, statins and sclerostin-antibodies. After first promising results from animal and clinical studies in the early 2000s, BMP-2 was studied mainly in open tibia shaft fractures treated with intramedullary nailing. There are conflicting results from different randomized clinical trials (RCTs) regarding fracture healing time and complications compared to BMP-2 free control treatment in open tibia fractures, as BMP-2 could not show significant differences in patients treated with reamed nails compared to BMP-2 free control treatment with reamed nailing only. Given that fact, its official use was limited in Europe to open tibia shaft fractures treated with unreamed tibial nailing by the European Medical Agency (EMA). Another more recent RCT failed to show equivalence of BMP- 2 together with allograft versus autograft for the treatment of tibia fractures with critical size defects. Recombinant human parathyroid hormone has proven anabolic effects on bone metabolism and is commonly used in treatment of severe osteoporosis. Different animal trials suggested an enhancement effect in fracture healing by PTH. In several clinical trials, PTH seems to have a stimulative effect for lower limb fractures. Statins, commonly used in treatment of dyslipidemia, could also enhance fracture healing in animal trials, especially when they were applied locally at the fracture site. For statins, there is only one RCT that failed to show significant effects for the oral administration of statins in undisplaced distal radius fractures. The role of sclerostin in fracture healing has more and more been understood. Application of sclerostin antibodies has been shown to be beneficial for fracture healing in animal trials. However, no RCTs on the effect of sclerostin antibodies on fracture healing have been performed yet. In conclusion, the "magic bullet" for molecular enhancement of fracture healing has not been identified yet, at least not with its optimal dosage and delivery method.

Does Bone Mineral Density Differ between Fan-Beam and Pencil-Beam?: A Meta-Analysis and Systemic Review

Background

Dual energy X-ray absorptiometry (DXA) has evolved from pencil-beam (PB) to narrow fan-beam (FB) densitometers. We performed a meta-analysis of the available observational studies to determine how different modes of DXA affect bone mineral density (BMD) measurements.

Methods

A total of 1,233 patients (808 women) from 14 cohort studies were included. We evaluated the differences in BMD according to the DXA mode: PB and FB. Additionally, we evaluated the differences in BMD between the 2 types of FB mode: FB (Prodigy) and the most recent FB (iDXA). Pairwise meta-analysis was performed, and weighted mean differences (WMD) were calculated for (total lumbar, total hip, and total body).

Results

No significant difference was observed in total lumbar (pooled WMD, −0.013; P=0.152) and total hip BMD (pooled WMD, −0.01; P=0.889), between PB and FB. However, total body BMD was significantly lower in the PB compared to the FB group (pooled WMD, −0.014; P=0.024). No significant difference was observed in lumbar BMD (pooled WMD, −0.006; P=0.567), total hip (pooled WMD, −0.002; P=0.821), and total body (pooled WMD, 0.015; P=0.109), between Prodigy and iDXA.

Conclusions

The results of this study warrant the recommendation that correction equations should not be used when comparing BMD from different modes. Further research is still needed to highlight the ways in which differences between DXA systems can be minimized.