Subtalar arthrodesis for complications of intra-articular calcaneal fractures

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.

Low Preoperative Albumin Associated With Increased Risk of Superficial Surgical Site Infection Following Midfoot, Hindfoot, and Ankle Fusion

BACKGROUND

This study investigates the effect of malnutrition, defined by hypoalbuminemia, on rates of complication, readmission, reoperation, and mortality following midfoot, hindfoot, or ankle fusion.

METHODS

The National Surgical Quality Improvement Program (NSQIP) database was queried from 2005 to 2019 to identify 500 patients who underwent midfoot (n = 233), hindfoot (n = 261), or ankle (n = 117) fusion. Patients were stratified into normal (n = 452) or low (n = 48) albumin group, which was defined by preoperative serum albumin level <3.5 g/dL. Demographics, medical comorbidities, hospital length of stay (LOS), and 30-day complication, readmission, and reoperation rates were compared between groups. The mean age of the cohort was 58.7 (range, 21-89) years.

RESULTS

Hypoalbuminemia patients were significantly more likely to have diabetes (P < .001), be on dialysis (P < .001), and be functionally dependent (P < .001). The LOS was significantly greater among the low albumin group (P < .001). The hypoalbuminemia cohort also exhibited a significantly increased likelihood of superficial infection (P = .048). Readmission (P = .389) and reoperation (P = .611) rates did not differ between the groups.

CONCLUSION

This study shows that malnourished patients have an increased risk of superficial infection following foot and ankle fusions but are not at an increased risk of readmission or reoperation, suggesting that low albumin confers an elevated risk of surgical site infection.

LEVELS OF EVIDENCE

Level III, Retrospective cohort study.

Technique and Early Outcomes for High-Energy Calcaneus Fractures Treated With Staged External Fixation to Combined Open Reduction Internal Fixation and Subtalar Arthrodesis

OBJECTIVE

(1) To present an effective surgical technique for the treatment of open and high-energy calcaneal fractures with significant soft tissue injuries. (2) To present complications with this technique and to evaluate patient-reported outcomes of staged external fixation followed by delayed reconstruction with open reduction internal fixation (ORIF) and subtalar arthrodesis.

DESIGN

Retrospective case series.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

Twelve patients with 13 calcaneus fractures associated with open traumatic wounds (10 patients) or other severe soft tissue injury (ie, fracture blisters) between April 2013 and December 2019.

INTERVENTION

All patients were treated with staged ankle-spanning external fixation and delayed reconstruction with ORIF with subtalar arthrodesis.

MAIN OUTCOME MEASURES

Patient-Reported Outcomes Measurement Information System (PROMIS) outcomes are presented via the domains of physical function (PF), pain interference (PI), and depression (D) in addition to visual analog score. Complications with the injury and surgical procedure were reported as well.

RESULTS

Patients underwent initial stabilization on average 1.3 days (range, 0-12 days) from injury with stage II occurring on average 31.1 days (range, 18-42 days) from external fixation. Mean time to radiographic union was 5.6 months (range, 4-10 months). One-year mean PROMIS outcomes were as follows: PF final average of 37.4 with an average improvement of 12.2 (P < 0.01), PI final average of 62.2 with average improvement of 5.6 (P = 0.01), and D final average of 52.1 with average improvement of 6 (P = 0.12). Mean final visual analog score pain score was 3.6 with an average improvement of 2.25 (P = 0.01).

CONCLUSION

Staged treatment with initial external fixation followed by ORIF and subtalar arthrodesis in the setting of highly comminuted calcaneus fractures with significant soft tissue compromise effectively addresses both bony and soft tissue concerns while providing for positive outcomes postoperatively with regards to pain and function. There were minimal complications noted for this complex injury.

LEVEL OF EVIDENCE

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

Tibio-Talar-Calcaneal Nail Fixation for Ankle Fractures: A Systematic Review and Meta-Analysis

Unstable ankle fractures are traditionally treated with open reduction and internal fixation. An alternative surgical option is primary tibio-talar-calcaneal fusion. Our aims were to determine the indication, complication rates, and functional outcomes, of tibio-talar-calcaneal nailing when used as the primary treatment of ankle fractures. A multidatabase literature search was performed on December 14, 2019 according to PRISMA guidelines. All studies in the English language reporting complications and outcomes involving tibio-talar-calcaneal nailing for primary treatment of ankle fractures were included. Ten studies with 252 ankle fractures were included. Mean age of patients was 75.5 (32-101) years. Mean follow-up duration was 79 weeks (36-104 weeks). Surgical site infection occurred in 11.2% (95% confidence interval [CI] 6.3%-19%) of patients, implant failure occurred in 8.1% (95% CI 5%-12.8%) of patients, and unplanned return to operating room occurred in 10.1% (95% CI 6.1%-16.2%) of patients. There were no cases of wound dehiscence. All-cause mortality rate at the end of follow-up was 26.6% (95% CI 19.7%-34.9%). Average reduction in Olerud-Molander Ankle Score after surgery was 7.9 points (5.0-11.8). Eighty-one point five percent (95% CI: 67.4%-90.4%) of patients were able to return to similar preoperative mobility aid after surgery. Tibio-talar-calcaneal nailing is an alternative procedure for patients who have sustained fractures unsuitable for nonoperative management, but have low functional demands and at increased risks of complications after open reduction and internal fixation. About 81.5% (95% CI 67.4%-90.4%) of patients were able to return to a similar preinjury mobility status after tibio-talar-calcaneal nailing.

Percutaneous subtalar joint screw fixation of comminuted calcaneal fractures: a salvage procedure

INTRODUCTION

Malunited comminuted calcaneal fractures result in poor function due subtalar joint arthritis and altered biomechanics. We aimed to assess whether percutaneous subtalar joint screws after fracture reduction provide good outcomes for these difficult injuries.

METHODS

We retrospectively analysed 15 comminuted calcaneal fractures (in 14 patients) treated with percutaneous subtalar screw fixation. All patients had a minimum of 12 months' follow-up. Six patients had open injuries. On the preoperative and the latest postoperative radiograph, Bohlers angle, Gissane angle, calcaneal inclination, width and length, absolute foot height, and posterior facet height were measured. Preoperative computed tomography scans were used to classify the fractures by Sanders classification. Clinical outcome scores were recorded postoperatively.

RESULTS

Mean age was 34.2 ± 14.2 years. Minimum follow-up was 12 months (mean 17.2 ± 4.4 months). Nine patients had a Sanders 4, 3 had a Sanders 3AB, 2 had a Sanders 3BC, and 1 had a Sanders 3AC fracture. Eighty percent of patients had their angle of Gissane, absolute foot height, calcaneal length and inclination restored by this technique. Bohlers angle was restored back into the normal range in 54% of patients. Mean postoperative AOFAS score was 74 ± 11. AOFAS scores positively correlated with postoperative Bohlers angle (Pearson's correlation coefficient 0.85; p = 0.004). One patient (7%) had a wound breakdown postoperatively and three patients (20%) had heel pain from the screws, which improved after removal.

CONCLUSION

Percutaneous subtalar screws offer a reliable option to restore calcaneal anatomy in comminuted calcaneal fractures, with low complication rates. Over 80% of patients had their angle of Gissane, calcaneal length and inclination restored, and over 50% of patients had all radiological parameters restored by this technique. It offers the benefits of percutaneous reduction and fixation and this procedure may be considered an effective first stage prior to definitive subtalar fusion. Further work is needed to review the longer-term outcomes and the conversion rate to arthrodesis.

LEVEL OF EVIDENCE

IV (case series), Therapeutic.

Arthroscopic Subtalar Joint Arthrodesis: Topical Review

BACKGROUND

Advances in foot and ankle arthroscopy over the last 2 decades have allowed for subtalar joint arthrodesis to be performed arthroscopically. The potential advantages of the arthroscopic technique include higher fusion rates, lower complications, reduced perioperative morbidity, and accelerated rehabilitation. Arthroscopic arthrodesis may, however, not be appropriate in the setting of complex deformity correction or the need for other open procedures.

METHODS

Surgical techniques of arthroscopic subtalar joint arthrodesis are described. Outcomes and complications associated with these procedures are presented, based on a comprehensive literature review. Thirteen Level IV studies of moderate quality were included.

RESULTS AND CONCLUSION

Excellent arthrodesis union rates were achieved (average 96%, range 86%-100%), at a weighted average union time of 8.8 weeks (95% confidence interval 7.9-9.7). The overall complication rate was 21% (87/415 feet; range 10%-36.4%). Metal irritation was the most common complication (11.2%), followed by nerve injury (4.2%) and infection (0.9%). Similar fusion rates have been reported when comparing arthroscopic and open arthrodesis. Complication rates are also similar, excerpt for infection, which may be lower with arthroscopy. Three different approaches were used to access the subtalar joint with similar union and complication rates. There was no evidence that the use of bone graft or more than 1 screw improved outcomes. The superiority of arthroscopic subtalar fusion over open techniques cannot be demonstrated by the available studies.

LEVEL OF EVIDENCE

Level IV, case series.

Outcomes and Complications of Open vs Posterior Arthroscopic Subtalar Arthrodesis: A Prospective Randomized Controlled Multicenter Study

BACKGROUND

Open subtalar arthrodesis is the standard treatment for subtalar arthritis. Posterior arthroscopic subtalar arthrodesis (PASTA) has recently gained increasing popularity due to a shorter recovery time and better cosmesis. However, studies comparing outcomes and complications between these 2 techniques are limited.

METHODS

In total, 56 patients with subtalar joint arthritis were prospectively randomized to 2 parallel groups to receive either PASTA (n = 28 patients) or open subtalar arthrodesis (n = 28 patients). The minimum follow-up period was 12 months. Primary outcome was union rate confirmed on postoperative computed tomography (CT) scan. Secondary outcomes were union time; visual analog scale (VAS), Short Form-36 (SF-36), and Foot and Ankle Ability Measure (FAAM) scores; tourniquet time; and complications.

RESULTS

Union time (9.4 vs 12.8 weeks) and recovery time (time to return to activities of daily living [8.4 vs 10.8 weeks], work [10.6 vs 12.9 weeks], and sports [24.9 vs 32.7 weeks]) were significantly shorter with PASTA than with the open technique (P < .05 all). Both techniques led to significant improvements in all functional outcomes (FAAM, SF-36, and VAS scores; P < .01 all); however, there was no significant difference between the techniques in these outcomes (P > .05 all). Other outcomes, including tourniquet time (55.8 vs 67.2 min), union rate (96.3% vs 100%), and complication rate, were not significantly different between the techniques.

CONCLUSION

Both open and PASTA techniques led to significant improvements in pain and function in patients with isolated subtalar joint arthritis. Although short-term functional outcomes and complication rates were not significantly different between the techniques, the PASTA technique was better at shortening the union and recovery times.

LEVEL OF EVIDENCE

Level I, prospective multicenter randomized controlled trial.

Isolated Arthroscopic-Assisted Subtalar Fusion: A Systematic Review

BACKGROUND

The subtalar joint has a complex anatomic function that includes inversion and eversion of the hindfoot, assisting in walking on uneven surfaces. Arthritis is the most common pathological condition affecting this joint and can require fusion. The surgery can be performed open or with arthroscopic assistance. This systematic review assesses articles written on the safety and efficacy of isolated arthroscopic subtalar fusion.

METHODS

Using MEDLINE and Embase, we systematically reviewed articles published before May 21, 2020.

RESULTS

Of 395 articles, 17 on a total of 395 patients (409 operations) were included in the review. The average duration of follow-up was 40.0 months (range, 3 to 105 months). Radiographic evidence of union was reported for 95.8% of cases at an average of 11.9 weeks (range, 6 to 56 weeks) postoperatively. Delayed union was reported in 1.0% of patients and nonunion, in 4.3% of patients. In the articles reporting patient satisfaction, including pain relief, 95.4% of patients had positive outcomes. Postoperative complications were reported in 64 patients (16.2%), including 37 (9.4%) with symptomatic implants, 11 (2.8%) with dysesthesia or neuropathic pain, and 3 (0.8%) with postoperative infection.

CONCLUSIONS

Arthroscopic subtalar fusion is a safe and effective alternative to open subtalar arthrodesis, with high patient satisfaction rates, high union rates at similar follow-up intervals, and low complication rates. The aim of future research should be to determine the ideal cases for this approach as well as the most efficient arthroscopic surgical technique and postoperative rehabilitation to optimize function and union as seen on radiographs.

LEVEL OF EVIDENCE

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

Open Reduction and Primary Subtalar Arthrodesis for Acute Intra-articular Displaced Calcaneal Fractures

OBJECTIVE

To evaluate the rate of subtalar arthrodesis based on a computed tomography (CT) scan after open reduction and primary subtalar arthrodesis for acute, displaced, intra-articular calcaneal fractures.

DESIGN

Retrospective chart review.

SETTING

Single tertiary care practice.

PATIENTS

A retrospective chart review was performed to identify patients who sustained an acute, displaced, intra-articular calcaneal fracture and underwent open reduction and primary subtalar arthrodesis. Thirty-five patients participated in the study.

INTERVENTION

Each patient included in the study was treated with open reduction and primary subtalar arthrodesis.

MAIN OUTCOME MEASURES

All patients were evaluated with CT for arthrodesis of the posterior facet of the subtalar joint, which was quantitated. Other outcome measures included radiographic parameters, the Veterans RAND Item Health Survey, and the Foot and Ankle Ability Measure.

RESULTS

The median patient age was 47.8 years (range 21.5-79.5 years). The median patient follow-up was 34.4 months (range 4.6-104.1 months). The Sanders classification was as follows: 3% (1/35) type II, 40% (14/35) type III, and 57% (20/35) type IV. Based on a CT scan, primary subtalar union occurred in 94.3% (33/35) of patients.

CONCLUSIONS

Open reduction and primary subtalar arthrodesis for acute, displaced, intra-articular calcaneus fractures has a high rate of union and good pain and function outcomes. It should be strongly considered for patients with significant cartilage injury and comminution of the posterior facet.

LEVEL OF EVIDENCE

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

Subtalar distraction arthrodesis for calcaneal malunion - comparison of structural freeze-dried versus autologous iliac bone graft

BACKGROUND

This study aims to analyze the outcomes of subtalar distraction arthrodesis (SDA) for calcaneal malunion using structural freeze-dried iliac allograft (FDIA) compared to using autologous iliac bone (AIB).

METHODS

We retrospectively evaluated 57 consecutive cases (51 patients) of calcaneal malunion between March 2006 and December 2017. All patients were followed for an average of 22.8 months. All cases were treated by SDA using structural FDIA (17 cases, group 1), or AIB (40 cases, group 2). The outcome measures included the American Orthopaedic Foot and Ankle Society ankle-hindfoot (AOFAS) scores, visual analog scale (VAS) pain scores, and radiographic measurements.

RESULTS

The mean postoperative 3, 6, and 12 months of AOFAS scores and VAS pain score were significantly better in group 2 than those in group 1 (p < 0.05, for all). There were 3 cases (17.6%) of nonunion in the group 1, whereas the group 2 had 2 cases (5.0%), which did not shown significant difference between two groups (p = 0.492). Although the mean pre-, postoperative, and final follow-up radiologic parameters in both groups were similar, (p > 0.05, for all) the difference of talocalcaneal height, talocalcaneal angle, and talar declination angle from postoperative to final follow-up were significantly bigger in the group 1. (p < 0.05, for all).

CONCLUSION

Although union rate was not significantly different between the two groups, we obtained more favorable clinical and radiologic outcomes in the autologous iliac bone group. Using FDIA without any orthobiological agent for SDA, there were significant more loss of radiological parameters due to inferior incorporation and biomechanical properties. When considering the SDA for calcaneal malunion, routine use of FDIA without any orthobiological agents as an interpositional graft for SDA is not recommended.

Subtalar joint preparation using the Two Portal posterior arthroscopic technique versus the sinus tarsi Open approach: A cadaver study

BACKGROUND

Subtalar fusion is the treatment of choice for subtalar arthritis when conservative management fails. The procedure can be performed arthroscopically or through the open lateral sinus tarsi (LST) approach. The arthroscopic technique is less invasive and is associated with rapid recovery, but it is more technically challenging. One of the most important aspects of fusion is adequate preparation of the joint via denudation of articular cartilage. This study compares the efficacy of subtalar joint preparation between the lateral sinus tarsi approach and the posterior two-portal arthroscopic technique using cadaveric specimens.

MATERIALS AND METHODS

Nineteen below-knee fresh-frozen cadaver specimens were used. The subtalar joints of nine specimens were prepared through the LST approach, while ten were prepared arthroscopically. After preparation, all ankles were dissected at the subtalar joint and photographs were taken of the posterior facets of the calcaneus and talus. Total and prepared surface areas of the articular surfaces for both approaches were measured using ImageJ software and compared.

RESULTS

The LST technique resulted in significantly greater percent preparation of the posterior facet of the calcaneus, as well as of the subtalar joint as a whole. Overall, 92.3% of the subtalar joint surfaces (talus and calcaneus combined) were prepared using the LST technique, compared to 80.4% using the arthroscopic technique (p = 0.010). The posterior facet of the calcaneus was 94.0% prepared using the open technique, while only 78.6% prepared using the arthroscopic technique (p = 0.005).

CONCLUSION

The LST approach for subtalar arthrodesis provides superior articular preparation compared to the two-portal posterior arthroscopic technique. Given that joint preparation is a critical component of fusion, maximizing prepared surface area is desirable and the open approach may be more efficacious for fusion. When using the arthroscopic approach, it may be advisable to use an accessory portal if there is poor visualization or limited access to the joint space secondary to severe arthritis.

LEVEL OF EVIDENCE

V.

Common Pitfalls in Subtalar Joint Preparation for Arthrodesis via Sinus Tarsi Approach

This cadaveric study assessed factors that could lead to nonunions in subtalar joint arthrodesis. The purpose of this study was to assist surgeons in achieving sufficient joint preparation in hopes to achieve more frequent arthrodesis of the subtalar joint. We evaluated the influence of experience in regard to cartilage preparation of the joint. We also assessed which quadrants of the subtalar joint were more likely to have unprepared cartilage. The subtalar joints in 17 cadaveric limbs were prepared by 17 participants with differing levels of experience. After the cartilage was denuded, the percentage of unprepared cartilage in each subtalar joint was calculated. The medial quadrants were more likely to have unprepared surfaces. There was also a learning curve present with subtalar joint preparation, as seen by the significantly larger percentage of unprepared cartilage in cadavers prepared by first year residents.

Open reduction and internal fixation (ORIF) versus ORIF and primary subtalar arthrodesis for complex displaced intraarticular calcaneus fractures: An expected value decision analysis

Objectives:

To determine the optimal patient-oriented treatment between open reduction and internal fixation (ORIF) with or without primary subtalar arthrodesis (PSTA) for patients with displaced intraarticular calcaneus fractures (DIACFs, OTA 82-C3 and C4).

Design:

Expected value decision analysis.

Setting:

Academic military treatment facility

Participants:

One hundred randomly selected volunteers.

Intervention:

Hypothetical clinical scenario involving ORIF versus ORIF with PSTA.

Main outcome measurements:

Decision analysis was used to elucidate the superior treatment option based on expected patient values, composed of: the product of the average outcome probabilities established by previously published studies and the average ascribed patient utility values for each outcome probability. One-way sensitivity analysis was performed to quantify the amount of change required for the inferior treatment to equal or surpass the superior option.

Results:

Expected values for ORIF and ORIF with PSTA were 8.96 and 18.06, respectively, favoring ORIF with PSTA. One-way sensitivity analysis was performed by artificially decreasing the rate of secondary fusion following isolated ORIF thus increasing its overall expected value. Adjusting the rate of secondary fusion to 0%, the expected value of ORIF with PSTA nearly doubled that of ORIF (18.06 vs 9.45). Similarly, when adjusting the moderate and severe complication rates following ORIF with PSTA to 100%, the expected value of ORIF with PSTA still exceeded that of ORIF (15.45 vs 8.96, and 13.52 vs 8.96, respectively).

Conclusion:

Expected value decision analysis favors ORIF with PSTA as the optimal treatment for complex DIACF.

Effect of bone morphogenetic protein-2/hydroxyapatite on ankle fusion with bone defect in a rabbit model: a pilot study

Background

Revision ankle-fusion surgery after a failure of total ankle arthroplasty has a problem with bone-defect management by implant removal. For the reconstruction of bone defects, autogenous bone often causes minor and major complications. Recombinant human-bone morphogenetic protein-2 (rhBMP-2) plays essential roles in bone regeneration strategies, and hydroxyapatite (HA) is beneficial as the rhBMP-2 carrier. In this study, we evaluate whether rhBMP-2/HA can replace autogenous bone in a rabbit ankle-fusion model with distal tibia bone defect.

Methods

The bone defect was created in the distal tibia. The ankle fusion was performed by a cannulated screw from lateral malleolus and various treatments on bone defect. Thirty male white New Zealand rabbits were divided into three groups of 10 animals on each group dependent on treatment methods as control group (no treatment into defect), auto-bone group (autogenous bone treatment), and rhBMP-2/HA group (40 μL of 1 μg/mL rhBMP-2/100 μL HA). Bone formation on defect and the union of the ankle joint were evaluated by X-ray, micro-CT, and histological analysis at 8 weeks and 12 weeks, postoperatively.

Results

Radiographic assessment found the control and auto-bone groups still had the bone defect present, but rhBMP-2/HA group showed complete replacement of the defect with newly formed bone at 12 weeks. Micro-CT showed significantly higher new bone formation within the defect in the rhBMP-2/HA group than in the auto-bone and control groups at 8 weeks (p > 0.05 and p < 0.01, respectively) and 12 weeks (p < 0.05, p < 0.001, respectively). Fusion rate (%) analysis of micro-CT showed a higher percentage of union in the rhBMP-2/HA group than in the auto bone and control groups at 8 weeks (p > 0.05, p < 0.001, respectively) and 12 weeks (p < 0.001 and p < 0.001, respectively). The histological showed the highest osteointegration between distal tibia and talus in the rhBMP-2/HA group at 12 weeks.

Conclusions

This study indicated that rhBMP-2/HA showed much better bone fusion than did the autogenous bone graft and was effective in promoting fusion rate and improving the quality of the ankle joint fusion.

Cost-Effectiveness of Operative Versus Nonoperative Management of Patients With Intra-articular Calcaneal Fractures

OBJECTIVE

To assess the costs, health gains, and cost-effectiveness of operative versus nonoperative treatment of calcaneal fractures over a 5-year time horizon from both US societal and payer perspectives.

METHODS

The societal perspective analysis included both direct medical costs and costs for missed work, whereas the health care payer perspective analysis included only direct medical costs associated with treatment and complications. A decision tree simulation model was developed to estimate the direct medical and indirect costs (2018 US$) and quality-adjusted life-years (QALYs) for treatment of patients sustaining intra-articular calcaneal fractures fixed with an extensile lateral approach. Direct medical costs were obtained from a large US health care system in Utah, Intermountain Healthcare, and indirect costs from the literature. Utility and probability parameters were also derived from the literature. Parameter uncertainty was explored using both one-way and probabilistic sensitivity analysis.

RESULTS

From a US societal perspective, operative treatment costs less ($35,110 vs. $39,870) and yielded more QALYs (3.89 vs. 3.51) over 5 years compared with nonoperative treatment. At a willingness-to-pay threshold of $50,000 per QALY, operative fixation had an 89% probability of being cost-effective. From a health care payer perspective, operative management remained cost-effective as the incremental cost-effectiveness ratio is below the willingness-to-pay threshold of $50,000/QALY.

CONCLUSION

From both US societal and health care payer perspectives, operative treatment of displaced intra-articular calcaneal fractures utilizing an extensile lateral approach is cost-effective at commonly accepted willingness-to-pay thresholds compared with nonoperative treatment over a 5-year time horizon. Patient variability may impact cost-effectiveness and should be explored in future research.

LEVEL OF EVIDENCE

Economic Level III. See Instructions for Authors for a complete description of levels of evidence.

Subtalar Fusion Preparation: What Are We Really Doing? A Cadaver Study

Introduction. The open, lateral sinus tarsi approach is the most commonly used technique for subtalar arthrodesis. In this cadaver study, we measured the maximum joint surface area that could be denuded of cartilage and subchondral bone through this approach. Methods. Nine fresh frozen above-knee specimens were used. The subtalar joint was accessed through a lateral incision from the fibular malleolus distally over the sinus tarsi area to the level of the calcaneocuboid joint. Cartilage was removed from the anterior, middle, and posterior facets of the calcaneus and talus using an osteotome and/or curette. ImageJ was used to calculate the surface areas of undenuded cartilage. Results. No specimens were 100% denuded of cartilage on all 6 measured surfaces. The greatest percentages of unprepared surface area remained on the middle facet of the talus (18.66%) and the middle facet of the calcaneus (14.51%). The anterior facet of the talus was 100% denuded in 6 specimens, while the middle and posterior facets were 100% denuded in 3 specimens. The anterior facet of the calcaneus was also 100% denuded in 6 specimens, while the middle and posterior facets were 100% denuded in 3 and 4 specimens, respectively. The average total unprepared surface area per specimen was 8.67%. Conclusion. The lateral sinus tarsi approach provides adequate denudation of cartilage of the subtalar joint in most cases. Total percentage of unprepared joint surface may range from approximately 2% to 18%. Future clinical studies are warranted to assess whether this technique results in optimal union rates. Levels of Evidence:V, Cadaveric Study.

A Novel Method of Simultaneous In Situ Decompression of Lateral Calcaneal Bulge and Subtalar Arthrodesis Via a Single Incision for Malunion After Calcaneal Fractures

OBJECTIVE

The aim of this study was to introduce a novel method of simultaneous in situ decompression of lateral calcaneal bulge and subtalar arthrodesis via a single incision for malunion after calcaneal fractures and evaluate the feasibility of this method.

METHODS

From September 2010 to October 2011, six patients (five males and one female) with malunion and delayed heel pain after conservative treatment of displaced intra-articular calcaneal fractures were included in our study. The mean age of the six patients was 32.9 years (range, 25-71 years). Patients were treated with this novel technique at our department and the functional outcomes were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) scores during follow-up. Information of the six patients including surgical data and pre/postoperative function scores were retrospectively analyzed using SPSS 19.0 statistical software.

RESULTS

The average operation time between wire insertion and incision suture was 42.2 ± 11.5 min (range, 25-56 min). The blood loss in all patients was all less than 50 ml each. The average fluoroscopy time was 25.7 ± 11.6 s (range, 11-43 s). No wound-related and other short-term complications were recorded. Six patients who were included in our study were followed for an average period of 66.2 ± 4.7 months (range, 60-73 months). There was no patient lost to follow up. Heel pain was observed to be greatly improved preoperatively in all of the six patients. All patients restored to normal activity of life after surgery. Radiological evidence of fusion was observed in five patients. The average fusion time of these five patients was 3.5 months (range, 2-4 months). The remaining one failed to achieve fusion and the hardware removal was performed due to screw tail irritation. This patient was satisfied with the final outcomes subjectively after removal of hardware. The mean AOFAS scores at 24 months postoperative were 82.0 ± 7.0, which was greatly improved compared to preoperative (44.8 ± 10.7) (P < 0.05). The preoperative VAS pain scores were decreased from 5.8 ± 1.5 to 2.6 ± 1.4 at 24 months postoperative (P < 0.05) and slightly decreased to 2.0 ± 1.7 at 48 months postoperative (P < 0.05). No surgery-related complications were observed in any of the patients.

CONCLUSIONS

The novel technique can effectively relieve the heel pain, prompt functional recovery, decrease the incidence of complications, simplify the surgical procedure, and shorten the learning curve. Therefore, the technique is a feasible and worthwhile alternative in treating malunion after calcaneal fractures.

Systematic Review of Subtalar Distraction Arthrodesis for the Treatment of Subtalar Arthritis

BACKGROUND

Subtalar distraction arthrodesis (SDA) was developed as a means of treating the symptoms of subtalar arthritis. Despite almost 30 years of research in this field, many controversies still exist regarding SDA. The objective of this study was to present an overview of outcomes following SDA, focusing on surgical technique as well as clinical and radiographic results.

METHODS

MEDLINE and EMBASE were queried and data abstraction was performed by 2 independent reviewers. Inclusion criteria for the articles were (1) English language, (2) peer-reviewed clinical studies with evidence levels I to IV, (3) with at least 5 patients, and (4) reporting clinical and/or radiographic outcomes of SDA.

RESULTS

Twenty-five studies matched the inclusion criteria (2 Level III and 23 Level IV studies) including 492 feet in 467 patients. The most common indication for SDA was late complications of calcaneus fractures. Many different operative techniques have been described, and there is no proven superiority of one method over the other. The most commonly reported complications were nonunion, hardware prominence, wound complications, and sural neuralgia. All studies showed both radiographic and clinical improvement at the last follow-up visit compared with the preoperative evaluation. Pooled results (12 studies, 237 patients) demonstrated improved American Orthopaedic Foot & Ankle Society ankle-hindfoot scores with a weighted average of 33 points of improvement.

CONCLUSION

SDA provides good clinical results at short-term and midterm follow-up, with improvement in ankle function as well as acceptable complication and failure rates. Higher quality studies are necessary to better assess outcomes between different operative techniques.

LEVEL OF EVIDENCE

Level III.

Biomechanical comparison of plantar-to-dorsal and dorsal-to-plantar screw fixation strength for subtalar arthrodesis

Objective

To compare screw fixation strength for subtalar arthrodesis.

Methods

Eight matched pairs of cadaver feet underwent subtalar joint arthrodesis with two 7.3mm cannulated screws. Randomization was used to assign screw orientation, such that one foot in each pair was assigned dorsal to plantar screw orientation (DP Group), and the other foot, plantar to dorsal orientation (PD Group). Standard surgical technique with fluoroscopy was used for each approach. Following fixation, each specimen was loaded to failure with a Bionix ^® 858 MTS device, applying a downward axial force at a distance to create torque. Torque to failure was compared between DP and PD Groups using Student’s t test, with p=0.05 used to determine statistical significance.

Results

Statistical analysis demonstrated that the mean torque to failure slightly favored the DP Group (37.3Nm) to the PD Group (32.2Nm). However, the difference between the two groups was not statistically significant (p=0.55).

Conclusion

In subtalar arthrodesis, there is no significant difference in construct strength between dorsal-to-plantar and plantar-to-dorsal screw orientation. The approach chosen by the surgeon should be based on factors other than the biomechanical strength of the screw orientation.

Biomechanical Considerations in Rearfoot Fusions

This article discusses rearfoot fusions for foot and ankle surgeons. It establishes normal foot and ankle function primarily in the stance phase of gait. The foot is greatly affected by external and internal forces, which contribute to normal function or the need for compensatory mechanisms. As a result of compensation, many symptoms develop, often leading to debilitating disorders such as degenerative joint disease. The interaction of the ankle, subtalar, and midtarsal joints are outlined. Congenital deformities, trauma and abnormal compensation are reviewed along with corresponding sequelae. Surgery is often indicated to reduce symptoms, improve position, and help stabilize the foot.

Do clinical results of arthroscopic subtalar arthrodesis correlate with CT fusion ratio?

BACKGROUND

CT analysis of arthroscopic subtalar arthrodesis rarely finds complete fusion. The aim of the present study was to determine, at 12 months' follow-up of arthroscopic subtalar arthrodesis: (1) CT fusion ratio, (2) functional results, and (3) the correlation between the two.

HYPOTHESIS

Incomplete fusion ratio does not impair the result of arthrodesis.

MATERIALS AND METHODS

A continuous series of 22 arthroscopic subtalar arthrodeses was assessed at 12 months' follow-up. The procedure used a posterior approach without bone graft, with stabilization by 2 compression screws. Clinical assessment comprised of a numerical analog pain scale (NAS, AOFAS and SF12) scores. Satisfaction was assessed on an NAS and on Odom's criteria. CT analysis at 12 months determined the posterior subtalar joint fusion ratio.

RESULTS

At follow-up, 2 patients showed non-union (9.1%). Among the 20 patients with fusion (91%), fusion was complete (>67°) in 16 (72.7%) and partial (34-66%) in 4 (18.2%). Mean fusion ratio at 12 months was 77.7%±14.8 (range, 36-98%). Functional gains (Δ) were: Δ pain NAS 4.8±2 (range, 1-10) and Δ AOFAS score 31.1±14 (range, 10-59). Mean satisfaction score was 8±2.5 (range, 3-10). There were no significant correlations between fusion ratio and any clinical or satisfaction scores.

CONCLUSION

Although clinical gain was systematic, functional and satisfaction scores were independent of whether subtalar fusion ratio was partial or complete.

LEVEL OF EVIDENCE

IV, retrospective study.

Subtalar Joint Distraction Arthrodesis Utilizing a Titanium Truss: A Case Series

Subtalar joint distraction arthrodesis has been recommended for the treatment of conditions such as nonunion or malunion of subtalar joint arthrodesis posttraumatic arthritis. Both conditions are difficult to treat, because the deformities created in the frontal and sagittal planes of these conditions are complex. If these malalignments are not addressed, ankle joint instability and wear occur over time. In general, either autograft or allograft bone has been used to perform distraction arthrodesis of the subtalar joint. Although studies have shown successful use, there have been complications. Autografts have resulted in donor site morbidity and limitations on graft size, and allografts have shown high nonunion rates. Both autografts and allografts have shown graft collapse over time. Recent literature has discussed the use of tantalum technology to span large defects in bone healing. Studies have shown that tantalum provides superior strength and bone incorporation compared with autografts and allografts. This case series presents 2 cases in which tantalum truss technology was used for distraction arthrodesis. Although this series is limited in patient numbers, both cases show effective graft incorporation with no loss in height over time and earlier return to activity compared with previous studies that used autograft and allograft wedges.

Distraction subtalar arthrodesis for calcaneal malunion

Aims

We hypothesized that there is no difference in the clinical and radiological outcomes using local bone graft versus iliac graft for subtalar distraction arthrodesis in patients with calcaneal malunion. In addition, using local bone graft negates the donor site morbidity.

Patients and Methods

We prospectively studied 28 calcaneal malunion patients (the study group) who were managed by subtalar distraction arthrodesis using local calcaneal bone graft. The study group included 16 male and 12 female patients. The median age was 37.5 years (interquartile range (IQR) 29 to 43). The outcome of the study group was compared with a control group of ten patients previously managed by subtalar distraction arthrodesis using iliac bone graft. The control group included six male and four female patients. The median age was 41.5 years (IQR 36 to 44).

Results

The mean American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score improved significantly in the study and the control groups (p < 0.001). Fusion was achieved in 27 patients in the study group at a median time of 13 weeks (IQR 12 to 14), while all the patients in the control group achieved fusion at a mean time of 13.2 weeks (11 to 15). The mean talocalcaneal height and talar declination angle improved significantly in both the study and the control groups (p < 0.001). There was no significant difference between both groups concerning the preoperative or the postoperative clinical and radiological measurements. Donor site morbidity was reported in four out of ten patients in the control group.

Conclusion

Local calcaneal bone graft can successfully be used to achieve subtalar distraction arthrodesis with appropriate correction of alignment and calcaneal malunion. We recommend using local instead of iliac bone graft as it gave comparable results and avoids the possibility of donor site morbidity. Cite this article: Bone Joint J 2019;101-B:596–602.

Arthroscopic and Endoscopic Management of Common Complications After Displaced Intra-Articular Calcaneal Fractures

The list of late complications after calcaneal fracture that can be treated through arthroscopic and/or endoscopic approach continues to expand. The late complications of calcaneal fractures can be classified into 3 groups: (1) those causing focal hindfoot or ankle pain, (2) those causing functional deficit, and (3) those present with diffuse and poorly localized pain. Many group 1 and some group 2 complications can be managed arthroscopically and/or endoscopically. There are usually multiple coexisting sources of the pain. Careful evaluation and analysis of a problem and detailed surgical planning with combination of arthroscopic/endoscopic and open procedures are key to success.

Arthroscopic Subtalar Arthrodesis: Does the Type of Fixation Modify Outcomes?

The goal of the present study was to analyze a modified American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale score, time to union, and the incidence of fusion after isolated arthroscopic posterior subtalar arthrodesis using either 1 or 2 screws of different diameters. We reviewed a consecutive series of 65 patients, mean age 50.0 ± 15.6 years, including 38 males (58.5%) and 27 females (41.5%), who had undergone arthrodesis from May 2004 to February 2011. The mean follow-up duration was 57.5 (range 24 to 105) months. The patients were divided into 3 groups according to the fixation method used: group 1 (n = 12; 18.5%) underwent fixation with one 6.5-mm screw; group 2 (n = 40; 61.5%) with one 7.3-mm screw; and group 3 (n = 13; 20%) with two 7.3-mm screws. An overall statistically significant (p <.0001) improvement was seen in the modified AOFAS scale score for all 3 fixation groups; however, the difference was not statistically significant (p = .79) among the fixation groups. Fusion was achieved in 62 patients (95.4%) after a mean of 12.1 (range 9 to 16) weeks. The difference in the time to union was not statistically significant (p = .781) among the fixation groups. Nine patients (13.8%) experienced complications, and nonunion was significantly (p = .005) more prevalent in the single 6.5-mm screw group. In conclusion, all 3 screw configurations led to improved modified AOFAS scale scores, although nonunion was more common among patients fixed with a single 6.5-mm screw.

Open Technique for In Situ Subtalar Fusion

The subtalar joint plays an important role for the hindfoot when accommodating during gait. Joint degeneration may be caused by posttraumatic, inflammatory, and pathologic biomechanical changes. Once conservative treatment has failed, subtalar fusion should be considered. The indication for surgery is based on thorough clinical and radiographic evaluation. Several techniques for subtalar fusion are published in literature. This article aims to describe a technique for in situ arthrodesis of the subtalar joint, paying special attention to biomechanical aspects as well as preoperative clinical and radiological work-up.

Arthroscopic posterior subtalar arthrodesis for salvage of posttraumatic arthritis following calcaneal fractures

BACKGROUND

Subtalar arthrodesis is a treatment option for pain due to posttraumatic arthritis following calcaneal fractures. The goal of this study is to examine the results of arthroscopic subtalar arthrodesis for posttraumatic arthritis following calcaneal fractures.

PATIENTS AND METHODS

We performed a retrospective case series reviewing 37 consecutive patients (36 male) treated for posttraumatic arthritis following calcaneal fractures by arthroscopic subtalar arthrodesis. The fractures were due to high-energy injuries in 81% of cases, and 12 fractures (32.4%) had been previously treated with internal fixation. Average follow-up was 57.5 months.

RESULTS

Average American Orthopedic Foot and Ankle Society (AOFAS) scores significantly improved from 49.0 ± 10.9 points preoperatively to 76.0 ± 8.0 points at final follow-up. Average time to union was 12.5 weeks. Six patients (16.2%) suffered complications: superficial wound infection (2.7%), symptomatic hardware that warranted removal (5.4%) and nonunion (8.1%) presented nonunion. All three cases had prior internal fixation through an extensile lateral approach, and fused after a repeat surgery.

CONCLUSION

Arthroscopic subtalar arthrodesis offers consistent improvement in cases of posttraumatic arthritis following calcaneal fractures, with a union rate similar to published series of open arthrodesis. We observed more nonunions in patients who had been treated previously with internal fixation. In spite of this, we continue to recommend arthroscopic subtalar arthrodesis, as it preserves the soft tissue envelope better than open techniques.

Factors Influencing Functional Outcomes of Subtalar Fusion for Posttraumatic Arthritis After Calcaneal Fracture

BACKGROUND

Subtalar arthrodesis is a common salvage operation for posttraumatic subtalar arthritis. This study aimed to identify factors associated with functional outcomes and quality of life after subtalar fusion for posttraumatic subtalar arthritis after calcaneal fracture.

METHODS

This is a retrospective study with follow-up by questionnaire in two level 1 trauma centers. Patients who underwent subtalar arthrodesis for posttraumatic arthritis after a calcaneal fracture between 2001 and 2016 were identified and contacted for completion of a survey consisting of the Foot and Ankle Ability Measure (FAAM), Maryland Foot Score (MFS), Patient-Reported Outcomes Measurement System Physical Function (PROMIS PF, Short Form 10a) questionnaire, EuroQol 5-dimensional (EQ-5D) questionnaire, and EuroQol visual analog scale (EQ-VAS). Exclusion criteria were initial subtalar arthrodesis at an outside facility, primary arthrodesis for fracture, initial arthrodesis earlier than 2001, amputation of the fused foot or leg, younger than 18 years at time of fusion, and inability to communicate in English. A total of 159 patients met our inclusion criteria. Eighty-four patients completed the questionnaires, resulting in a response rate of 59%.

RESULTS

Median FAAM score was 79 (interquartile range [IQR], 48-90), median MFS was 74 (IQR, 56-86), and median PROMIS PF was 45 (IQR, 38-51). Quality of life was significantly lower when compared to a reference population ( P = .001). Smoking was independently associated with worse outcomes. Complications after fusion (such as nonunion, implant failure, and infectious complications), high-energy trauma, and ipsilateral injury were also predictors for poorer outcomes.

CONCLUSION

Acceptable functional outcomes and quality of life were observed after subtalar fusion. Smoking, complications after subtalar fusion, high-energy trauma, and presence of ipsilateral injuries were independently associated with worse functionality and quality of life.

LEVEL OF EVIDENCE

Prognostic level III, comparative series.

Large Osseous Defect Reconstruction Using a Custom Three-Dimensional Printed Titanium Truss Implant

Treatment of large osseous defects remains a difficult surgical challenge. Autografts and allografts have been known to undergo late collapse, because these options are not specifically designed to withstand the high loads of the foot and ankle. The inability to achieve the correct shape for reconstruction further limits their application. Large osseous defects will result during salvage after failed Lapidus bunionectomy, explantation of failed total ankle replacements, and nonunion of Evans calcaneal osteotomy. Each of 3 patients received a 4WEB custom 3-dimensional (3D) titanium truss implant (Patient Specific Custom Implant; 4WEB Medical, Inc., Frisco, TX) for reconstruction. The mean follow-up period was 17.33 ± 3.51 months. Significant improvement was seen in pain, with a successful return to activities of daily living. The 12-month postoperative computed tomography findings demonstrated incorporation of the implant to the surrounding cortical and cancellous bone. No signs of delayed complications, such as stress shielding or implant failure, were found. This is the first case series to describe the use of a custom 3D-printed titanium truss implant to successfully contribute to reconstruction in the setting of failed elective foot and ankle surgery. This technology might play an important role in limb salvage of osseous defects that would otherwise require bone block arthrodesis with structural allograft or autograft bone.

Hybrid Fixation for Ankle Fusion in Diabetic Charcot Arthropathy

BACKGROUND

Ankle fusion is difficult to achieve in the diabetic Charcot ankle Brodsky type 3a because of the poor quality of the bone and the inability to achieve a stable biomechanical construct. The aim of this study was to report the outcome of ankle fusion using a combination of an intramedullary nail and a circular external fixator in patients with diabetic Charcot arthropathy.

METHODS

We prospectively studied 24 patients with diabetic Charcot arthropathy of the ankle who were treated by fusion of the tibiotalar joint using a combined retrograde intramedullary nail and Ilizarov external fixator. Their mean age was 50.7 ± 6.9 (range, 43-62) years. The mean follow-up after surgery was 36.4 ± 5.8 (range, 24-98) months.

RESULTS

Twenty-two patients (92%) achieved clinical and radiographic solid bony fusion. No patients in this series needed amputation. All the patients were pain free, and the mean American Orthopaedic Foot & Ankle Society Score (AOFAS) improved significantly from 34.6 ± 6.8 to 66.4 ± 4.5 at the last follow-up. Two patients developed an ulcer over the heel due to a prominent nail. The ulcer healed after nail removal. Eight patients developed pin tract infection.

CONCLUSION

We report a successful outcomes of ankle fusions using combined intramedullary nail locked only proximally and ring external fixator (hybrid fixation) in patients with diabetic Charcot arthropathy.

LEVEL OF EVIDENCE

Level IV, case series.

Sanders II/III Calcaneus Fractures in Laborers: A Cost-Effectiveness Analysis and Call for Effectiveness Research

OBJECTIVE

This study compares the cost and cost-effectiveness of treatments options for Sanders II/III displaced intra-articular calcaneus fractures (DIACFs) in laborers.

METHODS

Literature on Sanders type II and III fractures was reviewed to determine complication rates and utility values for each treatment option. Costs were calculated using Medicare reimbursement and implant prices from our institution. Monte Carlo simulations were used to analyze a decision tree to determine the cost and cost-effectiveness of each treatment from a societal perspective. Sensitivity analysis was performed on all variables.

RESULTS

Minimally invasive open reduction internal fixation (ORIF) (sinus tarsi approach with 4 screws alone) was least expensive ($23,329), followed by nonoperative care ($24,530) and traditional ORIF using extensile lateral approach ($27,963) (P < 0.001); this result was most sensitive to time out of work. Available cost-effectiveness data were limited, but our analysis suggests that minimally invasive ORIF is a dominant strategy, and traditional ORIF is superior to nonoperative care (incremental cost-effectiveness ratio $57,217/quality-adjusted life year).

CONCLUSIONS

Our findings suggest that minimally invasive ORIF (sinus tarsi approach) is the least expensive option for managing Sanders II/III displaced intra-articular calcaneus fractures, followed by nonoperative care. Our cost-effectiveness results favor operative management but are highly sensitive to utility values and are weakened by scarce utility data. We therefore cannot currently recommend a treatment course based on value, and our primary conclusion must be that more extensive effectiveness research (ie, health-related quality of life data, not just functional outcomes) is desperately needed to elucidate the value of treatment options in this field.

LEVEL OF EVIDENCE

Economic Level III. See Instructions for Authors for a complete description of levels of evidence.

Subtalar arthroscopic arthrodesis: Technique and outcomes

PURPOSE

The goal of this study was to describe the surgical technique and our results with arthroscopic posterior subtalar arthrodesis.

MATERIAL AND METHODS

Retrospective case series of 65 patients (38 men and 27 women) averaging 50 years of age (range 21-72 years) undergoing posterior arthroscopic subtalar arthrodesis using one or two percutaneous 6.5-7.3mm screws between May 2004 and February 2011, with a mean follow-up of 57.5 months (range 24-105 months).

RESULTS

We achieved a 95.4% union rate after an average of 12.1 weeks (range 9 to 16 weeks). 12.3% of patients suffered complications, including superficial infection, nonunion and need for hardware removal. The AOFAS score improved from 51.5 points (19-61 points) preoperatively to 81.9 points (60-94 points) in the postoperative period.

CONCLUSIONS

We describe the surgical technique for arthroscopic subtalar arthrodesis, which as proven to be a safe and reliable technique in our experience, with consistent improvements in AOFAS scores.

A Long-Term Study of the Effect of Subtalar Arthrodesis on the Ankle and Hindfoot Joints

BACKGROUND

Subtalar arthrodesis is a common therapy for subtalar joint disorders. In this article, we evaluate the effect of subtalar arthrodesis on the ankle and hindfoot joints.

METHODS

Fifty patients (33 men and 17 women) underwent subtalar arthrodesis between January 1, 1996, and August 31, 2011. The 36-item Short-Form Health Survey and American Orthopaedic Foot and Ankle Society ankle hindfoot scores were used for clinical evaluation. Radiographic analysis included assessment of degenerative changes and ankle and hindfoot joint function in the frontal and sagittal planes.

RESULTS

Thirty-seven patients (27 men and 10 women; mean age, 42.6 years) were followed up for an average of 9.2 years (range, 2-17 years). The mean ± SD 36-item Short-Form Health Survey score improved from 30.21 ± 7.19 before surgery to 78.50 ± 12.23, and the American Orthopaedic Foot and Ankle Society ankle hindfoot score increased from 50.32 ± 12.39 to 73.14 ± 15.44. Degenerative changes in the talonavicular, calcaneocuboid, metatarsocuboid, and ankle joints occurred. The talar-vertical angle was positively related to the tibial-plantar minimal angle (affected side: r = 0.56; P < .01; healthy side: r = 0.46; P < .01). The difference in hindfoot height is positively related to the difference in tibial-plantar minimal angle (r = 0.54; P < .01).

CONCLUSIONS

Subtalar arthrodesis is effective treatment for subtalar joint disease but could induce joint degeneration and ankle joint motion limitation related to talar declination and hindfoot height.

Role of Recombinant Human Bone Morphogenetic Protein-2 on Hindfoot Arthrodesis

Despite advances in understanding bone healing physiology and surgical techniques, delayed union and nonunion still occur after the treatment of hindfoot arthrodesis. There is increasing appeal of bone morphogenetic proteins (BMPs) owing to the innate osteoinductive abilities of BMPs. Effective treatment with BMPs has been shown in animal studies. Human clinical studies have also shown success. The only study investigating the use of recombinant human BMP (rhBMP)-2 in hindfoot arthrodesis found a significant increase in fusion rate. Treatment cost effective. Complications from their use remain low. rhBMP-2 is a safe and effective bone-healing adjunct in hindfoot arthrodesis surgery.

Compressive Force With 2-Screw and 3-Screw Subtalar Joint Arthrodesis With Headless Compression Screws

BACKGROUND

Joint compression is an essential element of successful arthrodesis. Although subtalar joint compression generated by conventional screws has been quantified in the laboratory, compression obtainable with headless screws that rely on variable thread pitch to achieve bony contact has not been assessed. This study measured subtalar joint compression achieved by 2 posteriorly placed contemporary headless, variable-pitch screws, and quantified additional compression gained by placing a third screw anteriorly.

METHODS

Ten, unpaired fresh-frozen cadaveric subtalar joints were fixed sequentially using 2 diverging posterior screws (one directed into the talar dome, the other into the talar neck), 2 parallel posterior screws (both ending in the talar dome), and 2 parallel screws with an additional anterior screw inserted from the plantar calcaneus into the talar neck. Joint compression was quantified directly during screw insertion using a novel custom-built measuring device.

RESULTS

The mean compression generated by 2 diverging posterior screws was 246 N. Two parallel posterior screws produced 294 N of compression, and augmentation of that construct with a third, anterior screw increased compression to 345 N (P < .05). Compression subsequent to 2-screw fixation was slightly less than that reported previously for subtalar joint fixation with 2 conventional lag screws, but was comparable when a third screw was added.

CONCLUSIONS

Under controlled testing conditions, 2 tapered, variable-pitch screws generated somewhat less compression than previously reported for 2-screw fixation with conventional headed screws. A third screw placed anteriorly increased compression significantly.

CLINICAL RELEVANCE

Because headless screws are advantageous where prominent screw heads are problematic, such as the load-bearing surface of the foot, their effectiveness compared to other screws should be established to provide an objective basis for screw selection. Augmenting fixation with an anterior screw may be desirable when conditions for fusion are suboptimal.

Complications of Intra-articular Calcaneal Fractures in Adults: Key Points for Diagnosis, Prevention, and Treatment

Calcaneal fractures are complex injuries with high complication rates and they can lead to serious disability. The proper management remains controversial and complications may occur regardless of the chosen type of treatment (operative or nonoperative). The present article reviews the studies that are related to the complications of calcaneal fractures. The incidence, the diagnosis, the prevention and the treatment of these complications were researched and analyzed, with the use of PubMed database, abstracts and original articles in English than investigate the etiology. The aim of the article is to discuss the most suitable management of the complications of calcaneal fractures and recommend a specific treatment as well as prevention methods.

LEVELS OF EVIDENCE

Level IV.

Quality of Early Union After First Metatarsophalangeal Joint Arthrodesis

The aim of the present retrospective cohort study was to assess the quality of union and the clinical outcomes in patients who had undergone first metatarsophalangeal joint (MTPJ) fusion using a dorsal plate and plantar lag screw. From March 2011 to December 2012, the clinical and radiographic data of 39 patients (41 feet) who had undergone first MTPJ fusion using a compressive locking plate were retrospectively reviewed. All patients had undergone postoperative computed tomography at 6 weeks postoperatively to assess union. The average metatarsophalangeal angles improved from 23° ± 16° preoperatively to 14° ± 5° postoperatively. The dorsiflexion of the hallux at the preoperative assessment averaged 17° ± 11° and 23° ± 5° postoperatively. At 6 weeks postoperatively, the computed tomography scans demonstrated 3 complete fusions (7.3 %) and 38 partial unions (92.7%). Also at 6 weeks, the mean ± standard deviation joint bridging was 54% ± 14.6%. The forefoot American Orthopaedic Foot and Ankle Society scale score had improved significantly from 50 ± 13 preoperatively to 80 ± 7 at >1 year of follow-up (p = .001). Hardware removal was performed in 8 cases because of pain in 7 and infection in 1. Revision arthrodesis was required in 2 cases because of nonunion. At 6 weeks postoperatively, partial bony joint bridging could be observed in most cases after arthrodesis of the first MTPJ with the dorsal fusion plate.

Subtalar Distraction Arthrodesis with Fresh Frozen Femoral Neck Allograft: A Retrospective Case Series

Subtalar joint distraction arthrodesis has been well reported with use of structural iliac crest or local autologous bone graft for malunited calcaneal fractures. Early reports for structural allograft did not yield good, consistent results, leading to a subsequent lack of recommendation in previous literature. Newer studies have had promising results utilizing femoral allograft as an alternative to autogenous bone graft. We performed a retrospective chart review on 10 patients (12 feet) undergoing subtalar joint distraction arthrodesis with femoral neck allograft for malunited calcaneal fractures. The primary aim of this study was to report on successful union rates and, in addition, outline any consistent complications. Twelve of the 12 procedures (100%) yielded successful fusion with a mean final follow-up of 7.7 months (range = 2.2-35.1 months). The mean increase in talocalcaneal height was 4 mm (range = 2-6 mm). The overall complication rate was 16.6%, including one superficial wound complication that healed uneventfully and one hardware removal. In conclusion, the current study reports a 100% successful fusion rate with interpositional structural femoral neck allograft in treatment for malunited calcaneal fractures.

LEVELS OF EVIDENCE

Therapeutic, Level IV: Case series.

Predictors of Nonunion and Infectious Complications in Patients With Posttraumatic Subtalar Arthrodesis

OBJECTIVE

The objective of the present study was (1) to identify predictors of both nonunion and postoperative wound infections (POWI) and (2) to assess the union and complication rate following posttraumatic subtalar arthrodesis (STA).

DESIGN

Retrospective comparative cohort study.

SETTING

Level 1 trauma center.

PATIENTS

All consecutive adult patients with STA following traumatic injuries between 2000 and May 2015.

INTERVENTION

STA for posttraumatic deformities.

MAIN OUTCOME MEASUREMENTS

Union (described as a combination of radiographic signs of osseous bridging and a clinically fused joint) and POWI as classified by the Centers for Disease and Control.

RESULTS

A total number of 93 (96 feet) patients met the inclusion criteria. Union was achieved in 89% of patients. For primary, secondary in situ, and secondary correction arthrodesis, these percentages were 94%, 84,% and 90%, respectively (NS). The union rate significantly increased over time (P = 0.02). In 17 patients (18%), a POWI occurred, of which 2 were classified as superficial and 15 as deep POWIs. The POWI rate did not differ between the groups. Alcohol, nicotine, and drug abuse were not significantly associated with the occurrence of POWIs. Patients with an open fracture or an infection following open reduction internal fixation had a greater risk of a POWI following STA (P = 0.03 and P = 0.04, respectively).

CONCLUSIONS

We could not identify predictors for nonunion. In 18% of the patients, an infectious complication following surgery occurred. Patients with an open fracture or an infection after primary surgical treatment (ie, open reduction internal fixation) have a higher chance of POWIs following STA. The union rate following posttraumatic STA is 89%.

LEVEL OF EVIDENCE

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

Operative treatment of calcaneal fractures: improved outcomes and low complications rates with a strict management protocol

This is a retrospective review of 80 intra-articular calcaneal fractures treated with open reduction and internal fixation by a specialist team under supervision of a single surgeon in a tertiary centre between 2005 and 2014. The fractures were evaluated with plain radiography and computed tomography, and graded using the Eastwood-Atkins classification. A lateral approach was used and all fractures were fixed with calcaneal plates. All patients had clinical and radiological follow-up. Clinical assessment included foot and ankle disability index, SF-36^® and Kerr-Atkins scores. The mean follow-up duration was 72 months (range: 12-130 months). The mean age of patients was 49 years (range: 17-73 years). There were three open fractures and eight patients had other injuries. The mean Bohler's angle improved from 6° preoperatively to 26° postoperatively. The mean foot and ankle disability index score was 78.62, the mean SF-36^® scores were 45.5 (physical component) and 52.6 (mental component), and the mean Kerr-Atkins score was 72 (range: 36-100). Early complications included one case of screw protrusion in the subtalar joint (which warranted a repeat procedure), one sural nerve injury and one wound breakdown, which healed with non-operative measures. Twelve patients had symptomatic subtalar joint osteoarthritis. Four of these had subtalar fusion. We believe that our strict protocols of patient selection, intraoperative and postoperative management produced long-term results comparable with those in the peer reviewed literature.

Calcaneus fractures

Assessment and treatment of calcaneal fractures have made substantial progress over the last two decades. Open reduction and stable internal fixation without joint transfixation has been established as standard therapy for most displaced intra-articular fractures with good to excellent results in more than two-thirds of patients in larger clinical series. The use of bone grafting or bone substitutes appears unnecessary in most cases. Important prognostic factors are anatomical reduction of subtalar joint congruity and the overall shape of the calcaneus. Therefore, quality of joint reduction should be reliably proved intra-operatively either with open subtalar arthroscopy or high-resolution (3D) fluoroscopy. Treatment results are adversely affected by open fractures, delayed reduction after more than 14 days, a high body mass index and smoking. The extended lateral approach respects the neurovascular supply to the heel and allows a good exposition of the fractured lateral wall, the subtalar and calcaneocuboid joints in complex fractures. In simple fracture patterns percutaneous screw fixation, supplemented by arthroscopic control if necessary, is a good alternative. Open fractures, compartment syndrome and fractures with severe soft tissue compromise are treated as emergency cases. Early, stable soft tissue coverage exploiting the full armamentarium of pedicled and free tissue transfer appears promising in improving the functional results and infection rates after open fractures. Calcaneal malunions after conservative therapy of displaced fractures are disabling conditions that can be treated successfully with a staged protocol according to the type of deformity. Treatment options include lateral wall decompression, in situ or correctional subtalar arthrodesis and calcaneal osteotomies.

Outcomes and Complications After Open Versus Posterior Arthroscopic Subtalar Arthrodesis in 121 Patients

BACKGROUND

Subtalar arthrodesis is a standard treatment for subtalar arthritis. Both open and arthroscopic techniques have been described and are commonly used. The cases of a consecutive series of 121 patients treated with either open or posterior arthroscopic techniques are presented with functional outcomes and complications.

MATERIALS

A retrospective chart review with prospectively collected data was performed for 121 consecutive patients (129 feet) who underwent subtalar arthrodesis with open (60 feet in 57 patients) or arthroscopic (69 feet in 64 patients) techniques between 2001 and 2014. The technique was selected on the basis of the deformity and surgeon preference. The primary outcomes were the visual analog scale (VAS) for pain, Short Form (SF)-36, Foot Function Index (FFI), and Angus and Cowell rating scores. Secondary outcomes included hindfoot alignment, operative time, length of hospital stay, fusion rate, time to return to work, ability to perform sports and activities of daily living, and complications.

RESULTS

Both groups demonstrated significant improvement in VAS, SF-36, FFI, and Angus and Cowell rating scale scores. The mean operative time, VAS score, Angus and Cowell rating score, and coronal plane hindfoot alignment were similar between the groups. There were no significant differences within the groups with respect to union rate and time to union among the various sizes of screws and types of bone graft. Sural nerve complications and a painful surgical scar were more frequent in the open group, whereas hardware-related symptoms were more frequent in the arthroscopically treated group.

CONCLUSIONS

Subtalar arthrodesis performed with open and arthroscopically assisted techniques demonstrated significant improvement in terms of pain and function as measured with the VAS, FFI, and SF-36. While the time to union and to return to work, activities of daily living, and sports activities were significantly shorter for the arthroscopic arthrodesis group, the union rates and complications overall were not significantly different.

LEVEL OF EVIDENCE

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

Biomechanical Evaluation of Strength and Stiffness of Subtalar Joint Arthrodesis Screw Constructs

BACKGROUND

Subtalar arthrodesis is a common treatment for end-stage subtalar joint arthritis as well as many other clinical problems. The best method of subtalar arthrodesis fixation is unknown. The purpose of this study was to compare the strength of subtalar arthrodesis fixation methods including a single posterior screw (SP), 2 posterior minimally divergent screws (MD) and a 2 screw highly divergent screw (HD) construct for subtalar arthrodesis.

METHODS

A biomechanical study was performed including the three different screw configurations (SP, MD, HD). These surrogate bone specimens were subjected to applied inversion and eversion torques about the subtalar joint axis on a servo-hydraulic load frame. Torsional stiffness of the construct and the maximum torque for each configuration were measured. Additionally, a cadaver study was performed using 5 fresh-frozen cadaver specimens. The perpendicular distance from the divergent screw guide-wire placement was measured from anatomic structures.

RESULTS

The HD screw configuration was found to have the highest torsional stiffness in both inversion and eversion, followed by the MD construct and then the SP construct. Similarly, the HD construct had the highest maximum torque versus the MD and SP constructs. All between-group differences were statistically significant (P < .05). The mean distance from key structures to the divergent screw included the sural nerve (13 mm), peroneus brevis tendon (18 mm), tibialis anterior tendon (8 mm), and tibialis posterior tendon (21 mm).

CONCLUSION

This biomechanical and cadaver study supports the use of 2 screws for fixation of subtalar arthrodesis over a single posterior screw. Additionally, we describe a biomechanically superior and potentially safe, alternative 2-screw divergent construct.

CLINICAL RELEVANCE

This study gives biomechanical support for 2 screw, divergent fixation of subtalar arthrodesis or a single over a single screw or two screw minimally divergent construct.

Isolated Subtalar Arthrodesis

Introduction

An isolated subtalar arthrodesis through a sinus tarsi approach with cannulated screw fixation is safe, reproducible, and effective for specific hindfoot pathology in adults.

Indications & Contraindications

Step 1 Preoperative Planning

Perform a comprehensive clinical and radiographic assessment.

Step 2 Patient Positioning

Position the patient supine on the operating table with a bump under the ipsilateral hip, to internally rotate the involved leg.

Step 3 Incision

Mark a longitudinal incision from just inferior to the tip of the lateral malleolus and extending toward the base of the 4th metatarsal.

Step 4 Approach

Expose the subtalar joint by reflecting the extensor digitorum brevis and protecting the peroneal tendons.

Step 5 Joint Preparation

Meticulously prepare the subtalar joint using osteotomes and curets down to healthy bleeding subchondral bone.

Step 6 Reduction and Fixation

Reduce the subtalar joint into 5° of valgus and fix it with cannulated screws.

Step 7 Wound Closure

Meticulously close the wound in layers and place the lower leg in a well-padded plaster back slab with the ankle in a neutral position.

Step 8 Postoperative Care

The operatively treated leg is kept immobilized and non-weight-bearing for the first 6 weeks.

Results

Numerous retrospective articles have reported high fusion rates and good functional outcomes after isolated subtalar arthrodesis, for all indications.

Pitfalls & Challenges

Results of Arthroscopic Subtalar Arthrodesis for Adult-Acquired Flatfoot Deformity vs Posttraumatic Arthritis

BACKGROUND

The goal of this study was to compare results with arthroscopic posterior subtalar arthrodesis between patients treated for adult-acquired flatfoot deformity (AAFD) due to posterior tibial tendon dysfunction and patients with posttraumatic subtalar arthritis.

METHODS

Retrospective case series of 61 consecutive patients (group 1: posttraumatic arthritis, n = 37; group 2: AAFD, n = 24) averaging 49 years of age (range, 21-72 years) undergoing posterior arthroscopic subtalar arthrodesis via 1 or 2 percutaneous 6.5- to 7.3-mm screws, with a mean follow-up of 57.5 months (range, 24-105 months). Fusion was defined as the appearance of bony trabeculae across the subtalar joint on standard x-rays, along with clinical signs of union.

RESULTS

Patients with posttraumatic arthritis (group 1) were more predominantly male and younger than patients treated for AAFD (group 2). Overall, we achieved a 95.1% radiologic union rate after an average of 11.7 weeks. Complications appeared in 14.8% of patients. Union rate and complications did not differ significantly between groups. American Orthopaedic Foot & Ankle Society (AOFAS) scores improved significantly for both patient groups, although patients with AAFD showed significantly larger improvement and higher postoperative AOFAS scores, even after adjusting for age and sex (mean improvement in AOFAS scores: 27.0 ± 9.1 points for the posttraumatic arthritis group vs 34.9 ± 7.4 points for the AAFD group; P < .001).

CONCLUSIONS

Arthroscopic subtalar arthrodesis was a safe and reliable technique, with consistent improvement in AOFAS scores throughout different patient subgroups, as well as comparable time to union and complication rates. Improvements were larger for patients treated for AAFD, even after adjusting for age and sex.

LEVEL OF EVIDENCE

Level III, retrospective case series.

Complex ankle arthrodesis: Review of the literature

Complex ankle arthrodesis is defined as an ankle fusion that is at high risk of delayed and nonunion secondary to patient comorbidities and/or local ankle/hindfoot factors. Risk factors that contribute to defining this group of patients can be divided into systemic factors and local factors pertaining to co-existing ankle or hindfoot pathology. Orthopaedic surgeons should be aware of these risk factors and their association with patients' outcomes after complex ankle fusions. Both external and internal fixations have demonstrated positive outcomes with regards to achieving stable fixation and minimizing infection. Recent innovations in the application of biophysical agents and devices have shown promising results as adjuncts for healing. Both osteoconductive and osteoinductive agents have been effectively utilized as biological adjuncts for bone healing with low complication rates. Devices such as pulsed electromagnetic field bone stimulators, internal direct current stimulators and low-intensity pulsed ultrasound bone stimulators have been associated with faster bone healing and improved outcomes scores when compared with controls. The aim of this review article is to present a comprehensive approach to the management of complex ankle fusions, including the use of biophysical adjuncts for healing and a proposed algorithm for their treatment.

Complex ankle arthrodesis: Review of the literature

Complex ankle arthrodesis is defined as an ankle fusion that is at high risk of delayed and nonunion secondary to patient comorbidities and/or local ankle/hindfoot factors. Risk factors that contribute to defining this group of patients can be divided into systemic factors and local factors pertaining to co-existing ankle or hindfoot pathology. Orthopaedic surgeons should be aware of these risk factors and their association with patients’ outcomes after complex ankle fusions. Both external and internal fixations have demonstrated positive outcomes with regards to achieving stable fixation and minimizing infection. Recent innovations in the application of biophysical agents and devices have shown promising results as adjuncts for healing. Both osteoconductive and osteoinductive agents have been effectively utilized as biological adjuncts for bone healing with low complication rates. Devices such as pulsed electromagnetic field bone stimulators, internal direct current stimulators and low-intensity pulsed ultrasound bone stimulators have been associated with faster bone healing and improved outcomes scores when compared with controls. The aim of this review article is to present a comprehensive approach to the management of complex ankle fusions, including the use of biophysical adjuncts for healing and a proposed algorithm for their treatment.

Isolated Subtalar Distraction Arthrodesis Using Porous Tantalum: A Pilot Study

BACKGROUND

During reconstructive procedures of the hindfoot, a structural graft is often needed to fill gaps. To eliminate donor site morbidity and limited availability of autografts, porous tantalum was used.

METHODS

Eighteen patients who underwent subtalar joint distraction arthrodesis by means of trabecular metal augment were reviewed retrospectively. The results were evaluated clinically, with the American Orthopaedic Foot & Ankle Society (AOFAS) score and the visual analog scale (VAS) for pain, and were assessed radiologically. The mean follow-up period was 18 months.

RESULTS

Computed tomography showed sound fusion. There was a marked increase in AOFAS scores and a decrease in VAS scores. Arthrodesis was achieved in all cases with no major postoperative complications. Radiographically, there was a marked increase in all measured parameters (talocalcaneal angle, talocalcaneal height, talar declination angle), and the intraoperatively achieved correction was maintained at the last follow-up visit.

CONCLUSION

Our data suggest that porous tantalum may be used as a structural graft option for subtalar arthrodesis.

LEVEL OF EVIDENCE

Level IV, retrospective case series.