Effects of teriparatide on fusion rates in patients undergoing complex foot and ankle arthrodesis

Nonunion in Foot and Ankle Arthrodesis Surgery: Review of Risk Factors, Identification of High-risk Patients, and a Guide to Perioperative Testing and Optimization

Foot and ankle arthrodesis surgery is often associated with high rates of nonunion ranging from 8% to 40%. This complication can result in individual patient burden and system burden in the management of these complex patients. Biologic factors contribute greatly to the development of a nonunion, including patient-related modifiable risk factors, metabolic and endocrine factors, systemic disease, previous surgeries, medications, weight loss treatments, and posttraumatic and postsurgical factors. Despite the high nonunion rate, there is a lack of high-level evidence in the identification of high-risk patients, strategies to minimize nonunion, and the management of patients with nonunion. An accepted standard of practice has not been established. This review aims to provide foot and ankle surgeons with (1) a comprehensive review of risk factors for nonunion, (2) a tool to identify high-risk patients using a preoperative patient questionnaire, (3) a clinical practice guide to preoperative and intraoperative testing that aims to improve preoperative counselling and patient optimization, and (4) perioperative strategies to minimize nonunion risk. With the above framework, our goal is to minimize nonunion risk in patients undergoing foot and ankle arthrodesis surgery to improve patient care and outcomes.

Comparative Studies of Bone Graft and Orthobiologics for Foot Ankle Arthrodesis: A Critical Review

Graft materials available to supplement hindfoot and ankle arthrodesis procedures include autologous (autograft) or allogeneic bone graft (allograft) but also bone graft substitutes such as demineralized bone matrix, calcium sulfate, calcium phosphate, and tricalcium phosphate/hydroxyapatite. In addition, biologic agents, such as recombinant human bone morphogenetic protein-2 or recombinant human platelet derived growth factor-BB (rhPDGF-BB), and preparations, including platelet-rich plasma or concentrated bone marrow aspirate, have been used to facilitate bone healing in ankle or hindfoot arthrodesis. The purpose of this review was to summarize the available clinical evidence surrounding the utilization and efficacy of the above materials and biological agents in ankle or hindfoot arthrodesis procedures, with emphasis on the quality of the existing evidence to facilitate clinical decision making.

Teriparatide and clodronate combination as a potential treatment for complex regional pain syndrome type I in delayed consolidation after foot surgery: a case report and review of the literature

BACKGROUND

Complex regional pain syndrome type I is a pathological condition characterized by an exaggerated response of tissues to low or moderate pain stimuli. The exact pathogenesis and optimal medical treatment for complex regional pain syndrome type I are still not fully understood, although bisphosphonates have shown positive effects in reducing pain. Foot surgery can be complicated by the development of complex regional pain syndrome type I, leading to functional decline and difficulties in weight-bearing.

CASE PRESENTATION

The authors present a clinical case involving complex regional pain syndrome type I that developed after surgical foot arthrodesis. The patient, a 42-year-old Caucasian male, did not respond to clodronate treatment but experienced successful outcomes upon the addition of teriparatide, which effectively stimulated the healing of arthrodesis.

CONCLUSION

Teriparatide cannot be considered the primary treatment for complex regional pain syndrome due to insufficient solid clinical data. However, when complex regional pain syndrome is associated with or caused by delayed union, teriparatide can be used to address the underlying cause of complex regional pain syndrome.

Association of Preexisting Triple Fusion and Arthroscopic Ankle Arthrodesis nonunion

BACKGROUND

Arthroscopic ankle arthrodesis (AAA) is a successful treatment for end-stage ankle arthritis. A significant early complication of AAA is symptomatic nonunion. Published nonunion rates range from 8% to 13%. Longer term, there is concern that it predisposes to subtalar joint (STJ) fusion. To better understand these risks, we undertook a retrospective investigation of primary AAA.

METHODS

All adult AAA cases conducted at our institution over a 10-year period were reviewed. A total of 284 eligible AAA cases in 271 patients were analyzed. The primary outcome measure was radiographic union. Secondary outcome measures included reoperative rate, postoperative complications and subsequent STJ fusion. Univariate and multivariate logistic regression analysis was performed to identify nonunion risk factors.

RESULTS

The overall nonunion rate was 7.7%. Smoking (odds ratio [OR] 4.76 [1.67, 13.6], P = .004) and previous triple fusion (OR 40.29 [9.46, 171.62], P < .001) were independent risk factors on univariate analysis. Only prior triple fusion persisted as a major risk factor associated with nonunion on multivariate analysis (OR 18.3 [3.4, 99.7], P < .001). Seventy percent of patients with a previous triple fusion went on to develop nonunion compared to 5.5% of those without. Increasing age, obesity, surgical grade, diabetes, postoperative weightbearing plan, steroid use, and inflammatory arthropathy were not significant risk factors. The leading cause of reoperation was hardware removal (18%). There were 5 superficial (1.8%) and 4 deep (1.4%) infections. Eleven (4.2%) required subsequent STJ fusion. The "survivorship" of STJ post AAA was 98%, 85%, and 74% at 2, 5, and 9 years, respectively.

CONCLUSION

As the largest study of AAA in the literature, our findings suggest prior triple fusion is a major independent risk factor for AAA nonunion. These patients should be counseled of this high risk and may benefit from alternative surgical options.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

CT-Verified Union Rate Following Arthrodesis of Ankle, Hindfoot, or Midfoot: A Systematic Review

BACKGROUND

Ankle, hindfoot, and midfoot arthrodesis surgeries are standard procedures performed in orthopaedics to treat pain and functional disabilities. Although fusions can effectively improve pain and quality of life, nonunions remain a significant concern for surgeons. With the increased availability of computed tomography (CT), more surgeons rely on this modality for increased accuracy in determining whether a fusion was successful. The objective of this study was to report the rates of CT-confirmed fusion following ankle, hindfoot, or midfoot arthrodesis.

METHODS

A systematic review was performed using EMBASE, Medline, and Cochrane central register from January 2000 to March 2020. Inclusion criteria included studies with adults (<18 years) that received 1 or multiple fusions of the ankle, hindfoot, or midfoot. At least 75% of the study cohort must have been evaluated by CT postoperatively. Basic information was collected, including journal, author, year published, and level of evidence. Other specific information was collected, including patient risk factors, fusion site, surgical technique and fixation, adjuncts, union rates, criteria for successful fusion (%), and time of CT. Once data were collected, a descriptive and comparative analysis was performed.

RESULTS

Included studies (26, n = 1300) had an overall CT-confirmed fusion rate of 78.7% (69.6-87.7). Individual joints had an overall fusion rate of 83.0% (73-92.9). The highest rate of union was in the talonavicular joint (TNJ).

CONCLUSION

These values are lower than previous studies, which found the same procedures to have greater than 90% fusion rates. With these updated figures, as confirmed by CT, surgeons will have better information for clinical decision making and when having informed consent conversations.

Nondiabetic Charcot Neuroarthropathy: Evaluation and Treatment

There are many similarities between nondiabetic and diabetic Charcot neuroarthropathy (CN) but many of the underlying causes causing nondiabetic neuropathy and CN are associated with poor bone quality. Patient workup for nondiabetic CN should include the underlying cause of the neuropathy and optimization of bony healing, such as vitamin D supplementation and bisphosphonate or calcitonin administration. Surgical reconstruction should include the most robust fixation possible, as nondiabetic patients with CN are more prone to delayed union.