Discontinuation of alendronate and administration of bone-forming agents after surgical nailing may promote union of atypical femoral fractures in patients on long-term alendronate therapy

Multicenter study on atypical femoral fractures in patients with bone metastases taking bone- modifying agents

Bone-modifying agents (BMAs), with bone-resorptive inhibitory effects, such as zoledronic acid and denosumab, are widely used at higher doses for bone-related events caused by bone metastasis of malignant tumors. These drugs have been suggested to be associated with atypical femoral fractures (AFFs), and the relationship between BMAs and AFFs has attracted attention. To investigate the clinical features including bone union time of AFFs in patients administered BMA for bone metastasis, we conducted a retrospective multicenter study. Thirty AFFs from 19 patients were enrolled in this study. Thirteen patients had bilateral AFFs, and nineteen AFFs had prodromal symptoms. Eighteen AFFs underwent surgery after complete fracture, three failed to achieve bone union and required nonunion surgery, and 11 AFFs that achieved bone union had an average period until bone union of 16.2 months, which was much longer than that previously reported for ordinary AFFs. Seven patients discontinued the BMAs, but not due to AFFs. Stopping BMAs in patients with bone metastasis would make it difficult to secure their performance of activities of daily living, and AFF with BMA administration might require a longer time for union. Therefore, it would be important to prevent incomplete AFF from becoming complete AFF via prophylactic internal fixation.

Atypical femoral fractures related to bisphosphonate treatment: issues and controversies related to their surgical management

AIMS

Treatment guidelines for atypical femoral fractures associated with bisphosphonates have not been established. We conducted a systematic review of the treatment of atypical femoral fractures first, to evaluate the outcomes of surgical fixation of complete atypical fractures and secondly, to assess whether prophylactic surgery is necessary for incomplete atypical fractures.

MATERIALS AND METHODS

Case reports and series were identified from the PubMed database and were included if they described the treatment of atypical femoral fractures. In total, 77 publications met our inclusion criteria and 733 patients with 834 atypical complete or incomplete femoral fractures were identified.

RESULTS

For complete fractures, internal fixation was predominantly achieved by intramedullary nailing. The mean time to healing post-operatively was 7.3 months (2 to 31). Revision surgery for nonunion or implant failure was needed in 77 fractures (12.6%). A greater percentage of fractures treated with plate fixation (31.3%) required revision surgery than those treated with intramedullary nailing (12.9%) (p < 0.01). Non-operative treatment of incomplete fractures failed and surgery was eventually needed in nearly half of the patients (47%), whereas prophylactic surgery was successful and achieved a 97% rate of healing.

CONCLUSION

Intramedullary nailing is the first-line treatment for a complete fracture, although the risk of delayed healing and revision surgery seems to be higher than with a typical femoral fracture. Non-operative treatment does not appear to be a reliable way of treating an incomplete fracture: prophylactic intramedullary nailing should be considered if the patient is in intractable pain. Radiographs of the opposite side should be obtained routinely looking for an asymptomatic fracture. Bisphosphonates must be discontinued but ongoing metabolic management in the form of calcium and/or vitamin D supplements is advisable. Teriparatide therapy can be considered as an alternative treatment. Cite this article: Bone Joint J 2017;99-B:295-302.

A Review of Atypical Femoral Fractures From a Tertiary Care Teaching Hospital: An Alarming Trend?

OBJECTIVE

To evaluate the experience of a single tertiary care teaching hospital with the association between use of bisphosphonates and atypical femoral fractures, and to identify potential risk factors and chronologic incidence.

DESIGN

Retrospective review.

SETTING

Tertiary-care teaching hospital.

PATIENTS

Thirty-two patients with a total of 43 fractures met inclusion criteria.

INTERVENTION

Treatment for atypical femur fractures.

MAIN OUTCOME MEASUREMENTS

Radiographic assessments, duration of bisphosphonate therapy, prodromal symptoms, associated medications/comorbidities.

RESULTS

Thirty-one female patients and 1 male patient, with a total of 43 fractures, with an average age of 71.0 (47-92 years) ± 11.01 years at time of fracture, had an average duration of bisphosphonate therapy of 7.57 (1-12 years) ± 3.07 years. Prodromal thigh pain was reported in 20 of 43 fractures (46.5%). Eleven of the forty-three (25.5%) fractures occurred between 2001 and 2005. From 2006 to May 2011, however, 32/43 (74.5%) were reported. Beta-blockers, ACE/ARBs, and Statins (43.8%) were the most common concomitant medications, whereas Levothyroxine (21.8%), H-2 blockers (15.6%), and Glucocorticoids (12.5%) were less common.

CONCLUSIONS

There is an increasing trend of atypical femur fractures in the current adult population. Bisphosphonate therapy beyond 7 years may place patients at increased risk.

LEVEL OF EVIDENCE

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

Healing of bisphosphonate-associated atypical femoral fractures in patients with osteoporosis: a comparison between treatment with and without teriparatide

Atypical femoral fracture (AFF) often appears with bisphosphonate use. Teriparatide (TPTD) treatment may promote AFF healing, but few controlled or comparative studies have examined the effects of TPTD on healing of bisphosphonate-associated AFF. We retrospectively reviewed the medical records of 45 consecutive AFFs in 34 Japanese patients who had received oral bisphosphonates (alendronate or risedronate) for osteoporosis before AFF and had been followed for ≥12 months (range, 12-90 months). Thirty-seven complete or incomplete AFFs (82 %) were treated surgically and eight incomplete AFFs (18 %) were treated conservatively. Bisphosphonates were stopped at diagnosis. Based on TPTD use after fracture, AFFs were divided into non-TPTD (n = 24) and TPTD (n = 21) groups. Time to fracture-healing and frequency of delayed healing or non-union were compared between groups. Because fracture type (complete or incomplete) differed significantly between groups, only subanalyses for all surgically treated AFFs (complete and incomplete), surgically treated complete AFFs, and conservatively treated incomplete AFFs were performed. In subanalyses for all AFFs treated surgically, mean (± standard deviation) time to fracture healing was significantly better in the TPTD group (5.4 ± 1.5 months) than in the non-TPTD group (8.6 ± 4.7 months; P = 0.012), and the frequency of delayed healing or non-union was significantly lower in the TPTD group than in the non-TPTD group (P = 0.014). Subanalyses for surgically treated complete AFFs yielded similar results, but subanalyses for incomplete AFFs treated conservatively showed no significant differences between groups. TPTD treatment appears to significantly shorten the postoperative time to fracture healing and reduce rates of delayed healing or non-union after bisphosphonate-associated AFF.

Atypical Femoral Fracture Despite Prophylactic Intramedullary Nailing: A Case Report

CASE

A forty-three-year-old woman on bisphosphonate therapy sustained an atypical femoral fracture that was successfully treated with an intramedullary nail. After she developed radiographic and clinical signs of an impending stress fracture of the contralateral femur, prophylactic nailing was performed. However, seven months postoperatively, she sustained a spontaneous, complete fracture of the prophylactically nailed femur at the site of the lateral cortical stress lesion.

CONCLUSION

To our knowledge, progression of a bisphosphonate-associated stress lesion to a complete fracture months after initially successful prophylactic intramedullary nailing has not been previously reported. Implications regarding treatment and prognosis are discussed.

Bisphosphonates and their influence on fracture healing: a systematic review

Bisphosphonates are commonly used in osteoporosis, but concerns have been raised about possible negative effects on fracture healing. We systematically reviewed the literature and found that bisphosphonates significantly prolong union times of distal radius fractures but not femoral fractures. The timing of bisphosphonate introduction does not affect fracture union time.

INTRODUCTION

Bisphosphonates are the most commonly prescribed drugs in patients suffering from and at higher risk of developing osteoporosis. However, concerns have been raised as to whether these drugs have a negative effect on fracture healing. The aim of this systematic review is to explore further these concerns.

METHODS

A literature review was performed in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All relevant articles found via MEDLINE, Cochrane, CINAHL, EMBASE and Google Scholar were screened. Studies with information on bisphosphonates' effect on fracture healing in humans were included and systematically reviewed.

RESULTS

Patients with distal radius fractures on bisphosphonates had a significantly longer union time compared with controls, but not patients with femoral fractures. No correlation between timing of bisphosphonate introduction and union time for fractures was found. Although one study reported a higher humeral non-union associated with bisphosphonate introduction following the fracture, there was no evidence that bisphosphonate introduction, timing or dose resulted in a significant delay in union following other fractures.

CONCLUSIONS

This systematic review has shown that bisphosphonates significantly prolong union times of distal radius fractures. Some clinical findings are in contrast with preclinical studies highlighting the need to develop better animal models to study osteoporosis, treatment and fracture healing. There is also a need for more well-constructed studies looking at the clinical effect of bisphosphonate on fracture healing in a large number of patients. These robust studies need to look at union time and non-union rates as a function of duration and dose of different bisphosphonates in different upper and lower limb fractures.

Pseudoarthrosis in atypical femoral fracture: case report

Atypical femoral fractures can be subsequent to a long-term biphosphonates treatment; they have a high frequency of delayed healing. The authors describe a femoral pseudoarthrosis of an atypical fracture treated with intramedullary nailing in a female after prolonged alendronate therapy. Atypical femoral fractures can be subsequent to a long-term biphosphonates treatment even if, in the literature, there is no clarity on the exact pathogenetic mechanism. The Task Force of the American Society for Bone and Mineral Research described the major and minor features to define atypical fractures and recommends that all the five major features must be present while minor features are not necessary. Another controversial aspect regarding the atypical femoral fractures is the higher frequency of the delayed healing that can be probably related to a suppressed bone turnover caused by a prolonged period of bisphosphonates treatment. This concept could be corroborated by the Spet Tc exam. In the case of a pseudoarthrosis, there is not a standardization of the treatment. In this report, the authors describe a femoral pseudoarthrosis of an atypical fracture treated with intramedullary nailing in a female after prolonged alendronate therapy; the patient was studied with clinical, bioumoral end SPECT-Tc exam of both femurs. Many studies show the relationship between bisphosphonates and the presence of atypical fractures. These fractures should be monitored more closely due to the risk of nonunion and they require considering an initial treatment with pharmacological augmentation to reduce the complications for the patient and the health care costs.