Clinical Outcomes of Nonunions of Hindfoot and Ankle Fusions

Clinical and Radiographic Outcomes After Hindfoot and Ankle Arthrodesis Using Cellular Bone Allograft Augmentation: A Short Report

Background

Nonunion after ankle or hindfoot arthrodesis is associated with poor outcomes. Cellular bone allograft is an alternative to autograft for use in these procedures. The purpose of this study was to prospectively evaluate the early efficacy and safety of cellular bone allograft use in hindfoot and ankle arthrodesis procedures.

Methods

Fourteen patients undergoing hindfoot or ankle arthrodesis supplemented with cellular bone allograft were prospectively enrolled. Computed tomography (CT) scans were obtained postoperatively at set time points and reviewed by 3 fellowship-trained foot and ankle surgeons as well as 1 musculoskeletal radiologist. Primary outcome was CT-verified union, defined as >25% of joint surface. Complications were recorded and revision procedures offered as indicated.

Results

CT-verified union rate during the study period was 76.7% (23 of 30 joints). Union was 100% for the ankle joint (2 of 2), 50% for the talonavicular joint (5 of 10), 100% for the calcaneocuboid joint (8 of 8), and 80.0% for the subtalar joint (8 of 10). One patient underwent revision fusion procedure, and 1 patient underwent hardware removal during the study period.

Conclusion

Our initial experience suggests that use of cellular bone allograft augmentation in hindfoot and ankle arthrodesis may offer an alternative to autograft without potential of donor site morbidity.

Level of Evidence

Level IV, case series.

Non-Union Treatment in the Foot, Ankle, and Lower Leg: A Multicenter Retrospective Study Comparing Conventional Treatment with the Human Allogeneic Cortical Bone Screw (Shark Screw®)

Addressing non-unions involves stabilizing the affected area through osteosynthesis and improving bone biology using bone grafts. However, there is no consensus on the optimal treatment method. This study aims to compare outcomes of non-union surgery using conventional treatment methods (metal hardware ± graft) versus osteosynthesis with the human allogeneic cortical bone screw (Shark Screw®) alone or in combination with a metallic plate. Thirty-four patients underwent conventional treatment, while twenty-eight cases received one or more Shark Screws®. Patient demographics, bone healing, time to bone healing, and complications were assessed. Results revealed a healing rate of 96.4% for the Shark Screw® group, compared to 82.3% for the conventionally treated group. The Shark Screw® group exhibited a tendency for faster bone healing (9.4 ± 3.2 vs. 12.9 ± 8.5 weeks, p = 0.05061). Hardware irritations led to six metal removals in the conventional group versus two in the Shark Screw® group. The Shark Screw® emerges as a promising option for personalized non-union treatment in the foot, ankle, and select lower leg cases, facilitating effective osteosynthesis and grafting within a single construct and promoting high union rates, low complications, and a rapid healing process.

The Fate of Delayed Unions After Isolated Ankle Fusion

BACKGROUND

Nonunion remains the most common major complication of ankle arthrodesis. Although previous studies have reported delayed union or nonunion rates, few have elaborated on the clinical course of patients experiencing delayed union. In this retrospective cohort study, we sought to understand the trajectory of patients with delayed union by determining the rate of clinical success and failure and whether the extent of fusion on computed tomography scan (CT) was associated with outcomes.

METHODS

Delayed union was defined as incomplete (<75%) fusion on CT between 2 and 6 months postoperatively. Thirty-six patients met the inclusion criterion: isolated tibiotalar arthrodesis with delayed union. Patient-reported outcomes were obtained including patient satisfaction with their fusion. Success was defined as patients who were not revised and reported satisfaction. Failure was defined as patients who required revision or reported being not satisfied. Fusion was assessed by measuring the percentage of osseous bridging across the joint on CT. The extent of fusion was categorized as absent (0%-24%), minimal (25%-49%), or moderate (50%-74%).

RESULTS

We determined the clinical outcome of 28 (78%) patients with mean follow-up of 5.6 years (range, 1.3-10.2). The majority (71%) of patients failed. On average, CT scans were obtained 4 months after attempted ankle fusion. Patients with minimal or moderate fusion were more likely to succeed clinically than those with "absent" fusion (P = .040). Of those with absent fusion, 11 of 12 (92%) failed. In patients with minimal or moderate fusion, 9 of 16 (56%) failed.

CONCLUSION

We found that 71% of patients with a delayed union at roughly 4 months after ankle fusion required revision or were not satisfied. Patients with less than 25% fusion on CT had an even lower rate of clinical success. These findings may help surgeons in counseling and managing patients experiencing a delayed union after ankle fusion.

LEVEL OF EVIDENCE

Level IV, 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.

The Trans-Achilles Approach for Plate Supplementation of Ankle Arthrodesis With an Existing Hindfoot Fusion Nail: A Case Report

Tibiotalar arthrodesis revision surgeries are not uncommon. Several approaches have been described in the literature for ankle arthrodesis nonunions. In this article, we describe the posterior trans-Achilles approach, which ensures adequate surgical exposure while minimizing damage to the surrounding soft tissues. It provides a convenient method for utilizing bone grafts or substitutes and allows for the advantageous application of posterior plating. The possible complications of this approach are delayed wound healing, wound infection, injury to the sural nerve, and the potential need for a skin graft. Despite the advantages of this approach, infection, delayed union, and nonunion risks remain high in this patient population. Finally, the trans-Achilles approach is valid for complex ankle procedures, especially in revisions with compromised ankle soft tissue envelopes.

Complex Ankle Fusion With Circular Frames: Factors Influencing Outcomes, Complications, and Patient Satisfaction

BACKGROUND

Circular frames for ankle fusion are reserved for complex clinical scenarios. The literature is heterogenous and conflicting. We aim to present the indications and outcomes of this procedure.

METHODS

A retrospective cohort study based on a prospective database of frame surgeries performed in a tertiary institution. Inclusion criteria were patients undergoing complex ankle fusion with circular frames between 2005 and 2020, with a minimum 12-month follow-up. Data were collected on patient demographics, surgical indications, comorbidities, surgical procedures, external fixator time (EFT), length of stay (LOS), radiologic and clinical outcomes, and adverse events. Factors influencing radiologic and clinical outcomes were analyzed.

RESULTS

47 patients were included, with a median follow-up of 30 months (interquartile range [IQR] 20-40). The median age at time of surgery was 63.5 years (IQR 58-71). Patients had a median of 2 previous surgeries (IQR 1-3). The median LOS was 8.5 days, and median EFT was 237 days (IQR 166-280). Simultaneous limb lengthening (median 3.3 cm, IQR 1.9-3.5) was performed in 11 patients, increasing the EFT by a mean of 4 months. Primary and final union rates were 91.5% and 95.7%, respectively. At last follow-up, ASAMI bone scores were excellent or good in 87.2%. ASAMI functional scores were good in 79.1%. Patient satisfaction was 83.7%. In addition, 97.7% of patients experienced adverse events, most commonly pin-site related, with major complications in 30.2% and reoperations in 60.5%. There were 3 amputations. Adverse events were associated with increased age, poor soft tissue condition, severe deformities, subtalar fusions, peripheral neuropathy, peripheral vascular disease, and prolonged EFT.

CONCLUSION

Complex ankle fusion using circular frames can achieve good outcomes, however time in frame may be prolonged with a high rate of adverse events. Identified risk factors for poorer outcomes should be considered in patient counselling and prognostication.

LEVEL OF EVIDENCE

Level III, prognostic.

How to assess consolidation after foot and ankle arthrodesis with computed tomography. A systematic review

PURPOSES

Many studies have been performed that investigate consolidation after arthrodesis of foot and ankle joints. Consolidation in foot and ankle joints is best assessed by computed tomography (CT). However, no golden-standard methodology exists for radiological consolidation assessment from CT after ankle and foot arthrodesis. The aim of this review is to present an overview of the radiological methodologies for consolidation assessment, outcomes on reliability and validity and to advise which methodology should be used.

METHOD

Scientific databases were systematically searched. Eligible studies were studies that 1) performed foot or ankle arthrodesis, 2) mentioned radiological or CT follow-up in abstract, 3) performed postoperative CT in > 50% of patients. Two authors selected eligible studies and performed a risk of bias assessment with the COSMIN tool.

RESULTS

Risk of bias assessment showed that most studies (80%) were at high risk of bias due to poor methodology. The most popular method for consolidation assessment is by subjectively categorizing consolidation into consolidation groups, with a substantial reliability score. Another popular method is to calculate the fusion ratio and then apply a fusion threshold, to distinguish between fused and non-fused joints. This method had an excellent reliability score. In most studies a fusion threshold of 50% is used. However, four studies in this review showed that a 30% fusion threshold may by more valid.

CONCLUSION

Based on the results of this review we would advise to calculate fusion threshold and apply a 30% fusion threshold to distinguish fused from non-fused foot and ankle joints.

Ankle Arthrodesis Combined With Mosaic Bone Autograft Transplantation for End-Stage Ankle Osteoarthritis With Large Cysts of Talar Dome

End-stage ankle osteoarthritis with large cysts of talar dome can be challenging to treat. Twenty patients diagnosed as end-stage ankle arthritis with large talar cysts between 04/2010 and 02/2016 were randomly divided into experimental group (10 cases) and conventional group (10 cases) by random number method. Patients in the experimental group were treated with ankle arthrodesis combined with a concomitant procedure of mosaic bone autograft transplantation, the conventional group under the ankle arthrodesis. The operation time, intraoperative blood loss, postoperative hospital stay, the time of bone union, and postoperative height of the talus between the 2 groups were compared. The preoperative and postoperative American Orthopaedic Foot and Ankle Society ankle-hindfoot scale score were also recorded and compared. There was no significant difference in the operation time, intraoperative blood loss, and postoperative hospital stay between the 2 groups. The postoperative height of the talus body and the time of bone union were better in the experimental group than that in the conventional group (p < .05). The results of follow-up showed that the American Orthopaedic Foot and Ankle Society scores of the conventional group were lower than those in the experimental group (p < .001). And the incidence of complication (10%) in the experimental group was significantly lower than that in the conventional group (40%). The use of tibiotalar arthrodesis combined with mosaic bone autograft transfer may be potentially an effective option for the treatment of end-stage ankle arthritis with large talar cysts.

Identifying Risk Factors for Nonunion of the Modified Lapidus Procedure for the Correction of Hallux Valgus

There is a paucity of literature characterizing risk factors for nonunion associated with the modified Lapidus procedure for correction of hallux valgus. The purpose of this study was to evaluate risk factors associated with nonunion for Lapidus bunionectomies. Patients who underwent modified Lapidus procedure from 2009 to 2018 were retrospectively reviewed. Patient's age, sex, body mass index, prior bunionectomy, history of tobacco use, presence of diabetes mellitus or hypothyroidism, and fixation method were recorded along with pre- and postoperative radiographic parameters. A multiple logistic regression analysis was implemented to estimate the odds of nonunion. Of the 222 patients who met inclusion criteria, nonunion with modified Lapidus procedure was observed in 20 patients (9.01%). Odds of nonunion with modified Lapidus procedure were greater for patients who had undergone previous bunionectomy (odds ratio [OR] = 3.957, 95% confidence interval [CI]: 1.021-15.338), as body mass index increased (OR = 1.091, 95% CI: 1.018-1.170), and as preoperative HV angle increased (OR = 1.108, 95% CI: 1.020-1.203). Odds of nonunion were lower for patients as preoperative intermetatarsal angle increased (OR = 0.739, 95% CI: 0.580-0.941). No significant increased odds of nonunion were found between fixation methods.

Persistent Pain After Hindfoot Fusion

One of the most challenging problems facing orthopedic surgeons is persistent pain after surgery and certainly is just as frustrating following hindfoot fusion. The hindfoot joints consist of the subtalar, talonavicular, and calcaneocuboid (CC) joints. These joints are commonly fused for degenerative changes, deformity correction, inflammatory or neuropathic arthropathy, tarsal coalition, or primarily after trauma. Goals of hindfoot fusion are a painless plantigrade foot capable of fitting in shoes without orthotics or a brace. Many believe that deformity correction is achievable without inclusion of the CC joint. Managing patient expectations is important when counseling a patient especially regarding potential complications.

Vitamin D Deficiency and Outcomes After Ankle Fusion: A Short Report

BACKGROUND

Vitamin D deficiency has been postulated as a cause for impaired bone healing and remodeling. The purpose of this study was to assess the potential association between low vitamin D levels and reoperation for nonunion following ankle fusion surgery.

METHODS

All adult patients (aged ≥18 years) who underwent ankle fusion procedures at a tertiary referral center from January 2010 to January 2019 with available vitamin D levels within 12 months preoperatively were retrospectively reviewed (n = 47). Patients were categorized as vitamin D deficient (<30 ng/mL) vs normal (31-80 ng/mL). The primary outcome was the incidence of reoperation secondary to nonunion. Secondary outcomes included incidence of reoperation not related to nonunion and the need for repeat reoperation.

RESULTS

The average level in the vitamin D-deficient group (n = 17; 36.2%) was 16.9 vs 46.4 ng/mL in the normal group (n = 30; 63.8%). All recorded reoperations for nonunion occurred exclusively in the vitamin D-deficient cohort (4/17 [23.5%]; P = .013). There were similar reoperation rates for causes other than nonunion (2/17 [11.8%] vs 4/30 [13.3%]; P > .99) and repeat reoperation rates (3/17 [17.6%] vs 1/30 [3.3%]; P = .128) among vitamin D-deficient vs normal patients.

CONCLUSION

Vitamin D deficiency may be associated with an increased risk of reoperation for nonunion after ankle fusion.

Sex Differences in End-Stage Ankle Arthritis and Following Total Ankle Replacement or Ankle Arthrodesis

BACKGROUND

We investigated the influence of sex on patient-reported outcomes preoperatively and following total ankle replacement and ankle arthrodesis.

METHODS

Patients who had undergone total ankle replacement or ankle arthrodesis for the treatment of end-stage ankle arthritis and who had ≥2 years of follow-up were identified from the Canadian Orthopaedic Foot and Ankle Society Prospective Ankle Reconstruction Database. Standard surgical techniques and implantation methods were followed, and STAR, Hintegra, Mobility, and Agility prostheses were used. Data were collected on patient demographics, revisions, secondary procedures, complications, Ankle Osteoarthritis Scale (AOS) scores, Short Form-36 (SF-36) scores, and expectations and satisfaction. Statistical analyses included 3-way repeated-measures analysis of variance (ANOVA) and multiple linear regression models controlling for inflammatory arthritis, age, preoperative scores, and surgery type.

RESULTS

The study included 872 patients: 629 who had undergone total ankle replacement (316 men, 313 women) and 243 who had undergone ankle arthrodesis (154 men, 89 women). The mean duration of follow-up (and standard deviation) was 4.9 ± 2.4 and 4.0 ± 1.9 years for the total ankle replacement and ankle arthrodesis groups, respectively. Men were older than women (p ≤ 0.001). In both the total ankle replacement and ankle arthrodesis groups, women had higher AOS pain scores (i.e., more pain) than men preoperatively (p < 0.05). Pain was reduced significantly in both sexes postoperatively (p < 0.05), with no significant difference between sexes. In both the total ankle replacement and ankle arthrodesis groups, women had higher AOS disability scores (i.e., more disability) and lower SF-36 Physical Component Summary (PCS) scores (i.e., worse function) than men both preoperatively and postoperatively (p < 0.001). Postoperatively, AOS disability and SF-36 PCS scores improved significantly from baseline in both sexes (p < 0.001). After controlling for covariates, sex was not a significant predictor of postoperative SF-36 MCS (Mental Component Summary), AOS pain, or AOS disability scores (p > 0.05) but explained 0.5% of variance in SF-36 PCS scores (p = 0.03). Sex did not significantly influence preoperative expectations or postoperative satisfaction. When patients with inflammatory arthritis were excluded, preoperative and postoperative outcome measures, expectations, and satisfaction were similar.

CONCLUSIONS

Men and women with end-stage ankle arthritis benefited from total ankle replacement and ankle arthrodesis with similar magnitudes of improvement. Small differences in pain and function between men and women undergoing total ankle replacement and ankle arthrodesis mostly disappeared when controlling for potential confounding variables. Both total ankle replacement and ankle arthrodesis remain good options for men and women with end-stage ankle arthritis.

LEVEL OF EVIDENCE

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

Fracture, nonunion and postoperative infection risk in the smoking orthopaedic patient: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to analyse negative effects of smoking in orthopaedic and trauma patients.

A PubMed search was carried out for studies published until July 2020 regarding effects of smoking on fracture risk, nonunion, infection after orthopaedic surgery, and persisting nonunion after scaphoid nonunion surgery. Random effects models calculated for outcome parameters, and relative risks (RR) with 95% confidence intervals are provided. No adjustments for covariates were made. Heterogeneity was assessed with Higgins’ I2, publication bias with Harbord’s p (Hp), sensitivity analysis performed on funnel plots and quality of studies was analysed using the Newcastle-Ottawa Scale.

Of 3362 retrieved entries, 69 were included in the final analysis. Unadjusted RR for smokers to develop vertebral (six studies, seven entries; RR: 1.61; p = 0.008; I2 = 89.4%), hip (11 studies, 15 entries; RR: 1.28; p = 0.007; I2 = 84.1%), and other fractures (eight studies, 10 entries; RR: 1.75; p = 0.019; I2 = 89.3%) was significantly higher. Postoperative infection risk was generally higher for smokers (21 studies; RR: 2.20; p < 0.001; I2 = 58.9%), and remained upon subgroup analysis for elective spinal (two studies; RR: 4.38; p < 0.001; I2 = 0.0%) and fracture surgery (19 studies; RR: 2.10; p < 0.001; I2 = 58.5%). Nonunion risk after orthopaedic (eight studies; RR: 2.15; p < 0.001; I2 = 35.9%) and fracture surgery (11 studies; RR: 1.85; p < 0.001; I2 = 39.9%) was significantly higher for smokers, as was persisting nonunion risk after surgery for scaphoid nonunion (five studies; RR: 3.52; p < 0.001; I2 = 0.0%). Sensitivity analysis for each model reduced heterogeneity whilst maintaining significance (all I2 < 20.0%).

Smoking has a deleterious impact on fracture incidence, and (subsequent) development of nonunions and postoperative infections.

Cite this article: EFORT Open Rev 2021;6:1006-1019. DOI: 10.1302/2058-5241.6.210058

Three-Dimensional Printed Cage in Patients With Tibiotalocalcaneal Arthrodesis Using a Retrograde Intramedullary Nail: Early Outcomes

Introduction. Segmental bone loss in the hindfoot hinders the chance of successful outcomes. Tibiotalocalcaneal arthrodesis is a reliable option; nevertheless, the risk of nonunion is high. Three-dimensional (3D) printed titanium implants offer a strong scaffold that can be customized and has demonstrated encouraging healing rates. In this study, we described the clinical outcomes and the radiologic union rate of a case series of patients with hindfoot arthrodesis, using a retrograde intramedullary nail associated to a 3D printed titanium cage. Methods. Seven patients undergoing hindfoot arthrodesis, using a retrograde intramedullary nail associated to a custom 3D printed titanium cage, were included. Demographic data were collected. Functional outcomes were assessed using the American Orthopedic Foot and Ankle Score and the Visual Analogue Scale for pain. Hindfoot alignment and radiographic union were evaluated using weight-bearing radiographs and computed tomography scan, respectively. Results. A total of 6 (85%) patients had more than 50% bony bridging. Only 1 patient underwent below knee amputation due to recurrence of chronic osteomyelitis. Two additional patients had minor complications. Conclusion. Tibiotalocalcaneal arthrodesis using customized titanium cages for patients with large bone defects has shown a high rate of union in those at risk of nonunion. However, further research with larger series is needed.Levels of Evidence: Level IV: Case series.

Orthobiologics in Foot and Ankle Arthrodesis: A Systematic Review

Orthobiologics are biologically-derived materials intended to promote bone formation and union. We review evidence on effectiveness and harms of orthobiologics compared to no orthobiologics for foot and ankle arthrodesis. We searched multiple databases (1995-2019) and included clinical trials and other studies with concurrent controls, English language, and reporting patient-centered outcomes, union/time to union, costs/resource utilization, or harms. Studies were organized by orthobiologic used. We describe quality and limitations of available evidence but did not formally rate risk of bias or certainty of evidence. Most of the 21 studies included were retrospective chart reviews with orthobiologics used at surgeon's discretion for patients considered at higher risk for nonunion. Ten studies compared autologous bone graft versus no graft and 2 compared remote versus local graft with few studies of other orthobiologics. All studies reported a measure of fusion and about half reported on function/quality of life. Few studies reported harms. Due to limited reporting, we were unable to assess whether effectiveness varies by risk factors for nonunion (eg, age, gender, smoking status, obesity, diabetes) or whether orthobiologics were cost-effective. Available evidence is of poor quality with small sample sizes, inadequate reporting of risk factors for nonunion, variations in orthobiologics, surgical techniques used, and outcome assessment, and potential selection bias. Research is needed to adequately inform surgeons about benefits and harms and guide patient selection for use, or type, of orthobiologics. Careful assessment of individual patient risk for nonunion is critical prior to orthobiologic use.

Nonunion Rates in Hind- and Midfoot Arthrodesis in Current, Ex-, and Nonsmokers

BACKGROUND

Nonunion rates in hind or midfoot arthrodesis have been reported as high as 41%. The most notable and readily modifiable risk factor that has been identified is smoking. In 2018, 14.4% of the UK population were active smokers. We examined the effect of smoking status on union rates for a large cohort of patients undergoing hind- or midfoot arthrodesis.

METHODS

In total, 381 consecutive primary joint arthrodeses were identified from a single surgeon's logbook (analysis performed on a per joint basis, with a triple fusion reported as 3 separate joints). Patients were divided based on self-reported smoking status. Primary outcome was clinical union. Delayed union, infection, and the need for ultrasound bone stimulation were secondary outcomes.

RESULTS

Smoking prevalence was 14.0%, and 32.2% were ex-smokers. Groups were comparable for sex, diabetes, and body mass index. Smokers were younger and had fewer comorbidities. Nonunion rates were higher in smokers (relative risk, 5.81; 95% CI, 2.54-13.29; P < .001) with no statistically significant difference between ex-smokers and nonsmokers. Smokers had higher rates of infection (P = .05) and bone stimulator use (P < .001). Among smokers, there was a trend toward slower union with heavier smoking (P = .004).

CONCLUSION

This large retrospective cohort study confirmed previous evidence that smoking has a considerable negative effect on union in arthrodesis. The 5.81 relative risk in a modifiable risk factor is extremely high. Arthrodesis surgery should be undertaken with extreme caution in smokers. Our study shows that after cessation of smoking, the risk returns to normal, but we were unable to quantify the time frame.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

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

BACKGROUND

Here, we determined whether teriparatide treatment would increase fusion rates after foot and ankle arthrodesis by comparing treatment results between patients with high-risk factors for nonunion who received teriparatide against those who did not.

METHODS

We retrospectively reviewed 66 consecutive patients who underwent foot and ankle arthrodesis. The inclusion criterion was the presence of at least one of the following risk factors for nonunion after previous foot and ankle arthrodesis: deformity, bone defects, avascular necrosis, and nonunion. Sixteen patients were finally enrolled and divided into 2 groups: 8 patients received teriparatide treatment after fusion surgery (PTH group), and 8 patients did not (control group).

RESULTS

The fusion rate was significantly greater in the PTH group than in the control group (100% vs 50%). Four patients in the control group developed nonunion, 3 of whom underwent revision fusion; however, all patients received the teriparatide treatment after revision surgery and subsequently achieved union. No significant differences in demographics, fusion sites, and complication rates were found.

CONCLUSION

Though the sample size was small, the current study suggests that teriparatide administration may improve fusion rates in patients with high-risk factors for nonunion after foot and ankle arthrodesis.

Tibial Stress Fracture Following Ankle Arthrodesis

BACKGROUND

End-stage ankle arthritis is frequently treated with either tibiotalar or tibiotalocalcaneal (TTC) arthrodesis, but the inherent loss of accommodative motion increases mechanical load across the distal tibia. Rarely, patients can go on to develop a stress fracture of the distal tibia without any antecedent traumatic event. The purpose of this study was to determine the incidence of tibial stress fracture after ankle arthrodesis, highlight any related risk factors, and identify the effectiveness of treatment strategies and their healing potential.

METHODS

A retrospective chart review was performed at 2 large academic medical centers to identify patients who had undergone ankle arthrodesis and subsequently developed a stress fracture of the tibia. Any patient with a tibial stress fracture before ankle arthrodesis, or with a nontibial stress fracture, was excluded from the study.

RESULTS

A total of 15 out of 1046 ankle fusion patients (1.4%) developed a tibial stress fracture at a mean time of 42 ± 82 months (range, 3-300 months) following the index procedure. The index procedure for these 15 patients who went on to subsequently develop stress fractures included isolated ankle arthrodesis (n = 8), ankle arthrodesis after successful subtalar fusion (n = 2), primary TTC arthrodesis (n = 2), and ankle arthrodesis subsequent to successful subtalar fusion with resultant ankle nonunion requiring revision TTC nailing (n = 3). Four patients had undergone fibular osteotomy with subsequent onlay strut fusion, and 5 had undergone complete resection of the lateral malleolus. Stress fracture location was found to be at the level of the fibular osteotomy in 2 patients and at the proximal end of an existing or removed implant in 9. Fourteen of the 15 patients had a nondisplaced stress fracture and were initially treated with immobilization and activity modification. Of these, 3 failed to improve with nonoperative treatment and subsequently underwent operative fixation (intramedullary nail in 2; plate fixation in 1). Only 1 of the 15 patients presented with a displaced fracture and underwent immediate plate fixation. All patients reported pain improvement and were ultimately healed at final follow-up.

CONCLUSION

In this case series review, we found a 1.4% incidence of tibial stress fracture after ankle arthrodesis, and both hardware transition points and a fibular resection or osteotomy appear to be risk factors. Operative intervention was required in approximately 25% of this population, but the majority of tibial stress fractures following ankle fusion were successfully treated nonoperatively, and ultimately all healed.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Is adjunction of advanced platelet-rich fibrin (A-PRF) useful in first metatarsophalangeal joint arthrodesis? A retrospective cohort study

PURPOSE

First metatarsophalangeal (MTPJ1) fusion represents the gold standard treatment for end-stage hallux rigidus (HR). The aim of this study was to assess efficacy and safety of A-PRF in promoting union after MTPJ1 arthrodesis. Our hypothesis was that the use of A-PRF may reduce the non-union rate and the time to fusion in the treatment of HR.

METHODS

14 patients that had undergone MTPJ1 arthrodesis with A-PRF adjunction with 21 standard MTPJ1 fusions were retrospectively reviewed. The fusion rate and time to fusion (clinically and radiographically) were assessed at 6, 12 weeks and at the longest follow-up; the clinical status at final follow-up through forefoot AOFAS, EQ5d, SEFAS and VAS-pain scores; the complication rate.

RESULTS

At 6-weeks, bony union was achieved in 100% of patients in the A-PRF group compared to 70% in the control group, but this difference was not statistically significant (p=0.22). At final follow-up (41 months), union rate in the control group reached 92% (one non-union). AOFAS, VAS and EQ-5d scores showed similar results for the two groups (p=0.86, p=0.12 and p=0.61, respectively); only SEFAS score revealed a difference favoring the A-PRF group (p=0.04). No revision surgery or complication was recorded in any group.

CONCLUSIONS

A tendency for increased union rate was mainly found at 6 weeks in patients treated with MTPJ1 fusion associated to A-PRF compared to isolated fusion. The use of A-PRF was not associated with an increased complication rate at final follow-up.

LEVEL OF EVIDENCE

Level 3, therapeutic study, retrospective comparative study.

Ankle Arthroscopy as an Adjunctive Method for Diagnosis of Nonunion After Tibiotalar Arthrodesis

The definition of consolidation after ankle arthrodesis can be challenging in some situations. Computed tomography has increased diagnostic accuracy; however, there are still no clear criteria for nonunion. In this context, arthroscopy with direct visualization of the arthrodesis may provide crucial data to inform the choice of treatment. The present report illustrates a case in which arthroscopy prompted a change in treatment strategy. More extensive surgery, with the potential for greater morbidity due to revision arthrodesis, could be avoided.

Recombinant Human Platelet-Derived Growth Factor BB in Combination With a Beta-Tricalcium Phosphate (rhPDGF-BB/β-TCP)-Collagen Matrix as an Alternative to Autograft

BACKGROUND

Joint arthrodesis often employs autograft to promote union; graft harvesting can lead to perioperative morbidity. A Canadian randomized controlled trial (RCT) demonstrated that recombinant human platelet-derived growth factor BB homodimer (rhPDGF-BB) combined with beta-tricalcium phosphate (β-TCP)-collagen was a safe, effective alternative to autograft. This multicenter North American RCT compared the safety and efficacy of rhPDGF-BB/β-TCP-collagen with autograft for ankle and hindfoot fusion. Subclassification using propensity scores (PS) incorporated patients from previous trials for enhanced statistical power for noninferiority testing and broader review of treatments.

METHODS

Patients requiring ankle or hindfoot arthrodesis and supplemental bone graft were treated with rhPDGF-BB/β-TCP-collagen (n = 69) or autograft (n = 35). Outcomes included joint fusion on computed tomography (24 weeks), clinical healing status, visual analog scale (VAS) pain, Short-Form 12 (SF-12), American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Scale, and Foot Function Index (FFI) scores over 52 weeks. PS methodology addressed potential selection bias arising from pooling data among these patients and 2 previous RCTs with similar inclusion criteria, surgical techniques, graft harvest techniques, and outcomes. All 132 rhPDGF-BB/β-TCP-collagen-treated patients and 167 of 189 candidate autograft-treated controls were selected for comparison by an independent statistician blinded to outcomes.

RESULTS

In the PS subclassification, 68.1% treatment patients and 68.4% controls achieved >50% osseous bridging at fusion sites. Clinical healing status was achieved in 84.8% of treated patients and 90.7% of controls at 52 weeks. Clinical, functional, and quality of life results demonstrated noninferiority of rhPDGF-BB/β-TCP-collagen to autograft. Safety-related outcomes were equivalent.

CONCLUSION

PS subclassification analysis of 3 RCTs demonstrated that rhPDGF-BB/β-TCP-collagen was as effective as autograft for ankle and hindfoot fusions, with less pain and morbidity than treatment with autograft.

LEVEL OF EVIDENCE

Level I, prospective randomized study.

Effect of Fixation Type and Bone Graft on Tarsometatarsal Fusion

BACKGROUND:

End-stage tarsometatarsal (TMT) arthritis is commonly treated with arthrodesis of involved joints. Fixation hardware can consist of varying combinations of screws, plates, and staples with or without supplemental bone graft. There are limited data to demonstrate either superiority of a given fixation method or the impact of bone graft on fusion rates. The purpose of this study, therefore, was to determine whether nonunion rates after TMT arthrodesis were influenced by either the use of screw vs plate fixation or the addition of bone graft vs no bone graft.

METHODS:

All patients older than 18 years undergoing arthrodesis for TMT arthritis between July 1991 and July 2016 were identified retrospectively. Exclusion criteria included less than 12 months follow-up, prior midfoot surgery, any added procedure beyond TMT arthrodesis using plates or screws, and acute foot trauma. All patients with radiographic or clinical nonunion, including those requiring revision surgery, were identified. Demographic data and associated risk factors were recorded via chart and radiographic image review. Eighty-eight patients (88 feet, mean follow-up: 75.1 ± 51.4; range, 12-179), with a total of 189 joints and who met enrollment criteria were treated by 9 different surgeons with arthrodesis.

RESULTS:

The overall nonunion rate was 11.4%. Significant independent risk factors associated with nonunion were (1) arthrodesis using plate fixation with all screws through the plate (odds ratio [OR], 6.2; 95% confidence interval [CI], 1.8-21.3; P = .004), (2) smoking during the perioperative period (OR, 7.9; 95% CI, 2.1-30.2; P = .002), and (3) postoperative nonanatomic alignment (OR, 11.2; 95% CI, 2.1-60.8; P = .005). Bone graft utilization was found to significantly lower the rate of nonunion (OR, 0.2; 95% CI, 0.1-0.6; P = .006).

CONCLUSION:

Isolated plate fixation, smoking, and postoperative nonanatomic alignment appear to significantly increase the rate of nonunion among patients undergoing TMT arthrodesis for midfoot arthritis. Concomitant use of autogenous bone graft significantly decreased this risk.

LEVEL OF EVIDENCE:

Level III, retrospective comparative study.

Prospective Cohort Study on the Employment Status of Working Age Patients After Recovery From Ankle Arthritis Surgery

BACKGROUND

People who are affected by end-stage ankle arthritis are as disabled as those suffering from arthritis in other main articulations of the lower extremity. Once these patients become unable to perform their job duties, they leave the workforce and require financial aid from government agencies, which represents a considerable economic burden. Regardless of whether arthrodesis or arthroplasty is performed, we hypothesized that patients younger than 55 years at the time of surgery should be able to return to work within 2 years and require less social assistance.

METHODS

Patients from 2002 to 2014 included in the nationwide prospective Ankle Reconstruction Database treated for end-stage ankle arthritis with a total ankle replacement or an ankle arthrodesis and younger than 55 years at the time of surgery were included. This study used a standard preoperative survey (AAOS, SF-36) along with the same survey filled by patients in intervals up to 2 years postoperatively. Their employment status was determined at each time point. Participation in third-party wage assistance programs was recorded. This cohort had 194 patients with an average age of 47.0 ± 7.2 years and was balanced in terms of sex (104 female) and side (94 left).

RESULTS

The employment rate prior to surgery was 56%, which increased to 62% at the 2-year postoperative mark. With regards to worker's compensation, disability, and social security, 20% of patients left all subsidized programs whereas 4% entered at least 1 which is significant (P < .05).

CONCLUSION

The 2-year follow-up after tibiotalar arthrodesis/arthroplasty in patients younger than 55 years showed that significantly more people were able to leave subsidized work assistance programs than enroll in them.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

The available evidence on demineralised bone matrix in trauma and orthopaedic surgery: A systematic review

Objectives

The aim of this systematic literature review was to assess the clinical level of evidence of commercially available demineralised bone matrix (DBM) products for their use in trauma and orthopaedic related surgery.

Methods

A total of 17 DBM products were used as search terms in two available databases: Embase and PubMed according to the Preferred Reporting Items for Systematic Reviews and Meta Analyses statement. All articles that reported the clinical use of a DBM-product in trauma and orthopaedic related surgery were included.

Results

The literature search resulted in 823 manuscripts of which 64 manuscripts met the final inclusion criteria. The included manuscripts consisted of four randomised controlled trials (level I), eight cohort studies (level III) and 49 case-series (level IV). No clinical studies were found for ten DBM products, and most DBM products were only used in combination with other grafting materials. DBM products were most extensively investigated in spinal surgery, showing limited level I evidence that supports the use Grafton DBM (Osteotech, Eatontown, New Jersey) as a bone graft extender in posterolateral lumbar fusion surgery. DBM products are not thoroughly investigated in trauma surgery, showing mainly level IV evidence that supports the use of Allomatrix (Wright Medical, London, United Kingdom), DBX (DePuy Synthes, Zuchwil, Switzerland), Grafton DBM, or OrthoBlast (Citagenix Laval, Canada) as bone graft extenders.

Conclusions

The clinical level of evidence that supports the use of DBM in trauma and orthopaedic surgery is limited and consists mainly of poor quality and retrospective case-series. More prospective, randomised controlled trials are needed to understand the clinical effect and impact of DBM in trauma and orthopaedic surgery.

Cite this article: J. van der Stok, K. A. Hartholt, D. A. L. Schoenmakers, J. J. C. Arts. The available evidence on demineralised bone matrix in trauma and orthopaedic surgery: A systemati c review. Bone Joint Res 2017;6:423–432. DOI: 10.1302/2046-3758.67.BJR-2017-0027.R1.