[Operative treatment of displaced intra-articular calcaneal fractures]

Early Surgery and Screw-Only Osteosyntheses in Minimally Invasive Treatment of Calcaneal Fractures-Risk or Benefit for Our Patients?

Background: This study aims to analyze the outcomes following the minimally invasive surgery of calcaneal fractures using screw-only osteosynthesis, as well as the impact of surgical timing. Methods: Between 2015 and 2020, 155 patients with 168 fractures were included. According to the Sanders classification, 48.21% of fractures were classified as Sanders 2, 33.33% as Sanders 3, and 10.11% as Sanders 4 fractures, with the remaining fractures unclassified. A total of 117 cases were treated on the day of admission or the following day. The surgeries followed a standardized protocol for fracture analysis, positioning, and X-ray techniques, primarily using a percutaneous approach with stab incisions. Osteosynthesis was mainly performed using screws, with five cases treated with K-wires for open fractures. Results: The mean Boehler's angle improved from 8.52° preoperatively to 25.00° postoperatively. Three superficial infections were observed. Deep infections occurred in three cases, all following open fractures. Secondary dislocation was noted in five patients-one due to a deep infection, and four attributed to clear technical failures. One case involved a questionable indication for a screw change (7.3 mm screw) after two weeks due to perforation of the medial wall. A total of 79 fractures were followed up for an average of 4 years and 3 months. The mean AOFAS score was 91.3, and the mean FAOS score was 88.7. Surgery within 7 days after admission showed no significant impact on the outcomes. Conclusions: Minimally invasive screw-only osteosynthesis with early surgical intervention offers favorable outcomes with minimal risk.

Postoperative complications after displaced intra-articular calcaneal fracture operations

BACKGROUND

The objective was to compare postoperative complications in the management of displaced intra articular calcaneal fractures (DIACF) between two groups; the open reduction and internal fixation (ORIF) group versus the percutaneous fixation (PF) group.

METHODS

A total of 243 DIACFs were diagnosed and 127 of them received operations either with ORIF 75 (59.1 %) or PF 52 (40.9 %) between 2004 and 2018. Postoperative complications, radiological Sanders's classification and improvement of Böhler's angle were analyzed.

RESULTS

Early complication rate (<6 weeks), rate of deep wound infections and wound edge necrosis were significantly better in PF than in ORIF patient group. There were no significant differences in late complications (>6 weeks from operation) nor in improvement of Böhler's angle.

CONCLUSION

Complication rate is lower when using PF technique while fracture reduction remains the same compared to the ORIF.

LEVEL OF EVIDENCE

IV retrospective cohort study at a single institution.

[Calcaneoplasty with radiofrequency cementing following balloon reduction]

The standard surgical procedure for complex calcaneal fractures is open reduction, internal reduction and internal stable angle plate osteosynthesis via a lateral approach. More recently, options for minimally invasive and percutaneous surgical strategies have been presented [4, 7]. As a possible procedural alternative for a covered, surgical treatment of calcaneal fractures, calcaneoplasty is discussed and applied in this context [5]. In this case series of five complex calcaneal fractures presented here, a balloon catheter was used for percutaneous reduction to restore the alignment of the calcaneus.This was followed by placement of PMMA cement in radiofrequency application and osteosynthesis using percutaneous cannulated screws. This Vicenti technique allows stable reduction and retention with early partial weight bearing with an overall low complication rate [17].

Clinical outcomes following treatment of deep surgical site infection after fixation of calcaneal fractures: A retrospective case-control study

INTRODUCTION

Deep surgical site infection (SSI) may be a complication of open reduction and internal fixation (ORIF) of calcaneal fractures. This study aimed to describe the characteristics of patients with deep SSI following ORIF of calcaneal fractures via extensile lateral approach (ELA). We compared clinical outcomes of these patients, with a minimum follow-up of one year after successful treatment of deep SSI with a matched control group.

METHODS

In this retrospective case-control study, demographic data, fracture characteristics, bacterial pathogens, medical treatments and surgical approaches were collected, also the outcome was evaluated by the visual analog scale (VAS) for pain, foot function index (FFI) and AOFAS ankle-hindfoot score. The differences in Böhler and Gissane's angles between infected and contralateral feet were measured. By matching a control group of uninfected cases, clinical outcomes were compared between 2 groups using the Mann-Whitney U test.

RESULTS

Among 331 calcaneus fractures in 308 patients (mean age, 38.0 ± 13.1; male/female ratio, 5.5), 21 had deep SSI (6.3 %). There were 16 (76.2 %) males and 5 (23.8 %) females with a mean age of 35.1 ± 11.7 years. Thirteen (61.9 %) patients had unilateral fractures. The most common Sanders Type was found to be type II. The most frequent type of detected microorganisms was Staphylococcus species. Intravenous antibiotic therapy, mostly clindamycin, imipenem and vancomycin, based on the microbiological results, was prescribed with a mean±SD duration of 28.1 ± 16.5 days. The mean number of surgical debridements was 1.8 ± 1.3. Implants needed to be removed in 16 (76.2 %) cases. Antibiotic-impregnated bone cement was applied in three (14.3 %) cases. The clinical outcomes of 15 cases (follow up, 35.5 ± 13.8; range, 12.6-64.5 months) were 4.1 ± 2.0, 16.7 ± 12.3 and 77.5 ± 20.8 for VAS for pain, FFI % and AOFAS ankle-hindfoot score, respectively. Comparing with the control group (VAS for pain, 2.3 ± 2.7; FFI %, 12.2 ± 16.6, and AOFAS, 84.6 ± 18.0), only VAS pain was statistically lower in this group (p-value: 0.012). The differences in Böhler and Gissane's angles between both feet of infected cases were - 14.3 ± 17.9 and - 7.7 ± 22.5 (worse in the infected side), respectively.

CONCLUSION

Proper on-time approaches to deep infection following ORIF of calcaneal fractures may lead to acceptable clinical and functional outcomes. Sometimes aggressive approaches with intravenous antibiotic therapy, multiple sessions of surgical debridement, removal of implants and antibiotic impregnated cement are necessary to eradicate deep infection.

LEVEL OF EVIDENCE

Level III.

Use of intramedullary locking nail for displaced intraarticular fractures of the calcaneus: what is the evidence?

INTRODUCTION

Intramedullary locking devices (ILDs) have recently been advocated as a minimally invasive approach to manage displaced intraarticular calcaneal fractures (DIACFs), to minimise complications and improve outcomes. We reviewed clinical and biomechanical studies dealing with commercially available devices to identify their characteristics, efficacy and safety.

METHODS

Following a PRISMA checklist, Medline, Scopus and EMBASE databases were searched to identify studies reporting the use of ILDs for treating DIACFs. Biomechanical studies were first evaluated. Cohort studies were then reviewed for demographics, surgical technique, postoperative protocol, clinical and radiographic scores, complications and reoperations. The modified Coleman Methodology Score (CMS) was used to assess the quality of studies.

RESULTS

Eleven studies were identified which investigated two devices (Calcanail®, C-Nail®). Three biomechanical studies proved they offered adequate primary stability, stiffness, interfragmentary motion and load to failure. Eight clinical studies (321 feet, 308 patients) demonstrated a positive clinical and radiographic outcome at 16-months average follow-up. Metalware irritation (up to 20%) and temporary nerve entrapment symptoms (up to 30%) were the most common complications, while soft tissue issues (wound necrosis, delayed healing, infection) were reported in 3-5% of cases. Conversion to subtalar fusion was necessary in up to 6% of cases. Four (50%) out of 8 studies were authored by implant designers and in 5 (62%) relevant conflicts of interest were disclosed. Mean (± standard deviation) CMS was 59 ± 9.8, indicating moderate quality.

CONCLUSIONS

Treating DIAFCs with ILDs leads to satisfactory clinical outcomes at short-term follow-up, enabling restoration of calcaneal height and improved subtalar joint congruency. Metalware irritation and temporary nerve entrapment symptoms are common complications although wound complications are less frequent than after open lateral approaches. The quality of evidence provided so far is moderate and potentially biased by the conflict of interest, raising concerns about the generalisability of results.

LEVEL OF EVIDENCE

Level V - Review of Level III to V studies.

Return-to-sports after minimally invasive stabilization of intra-articular calcaneal fractures

BACKGROUND

 Evaluation of different factors in patient quality of life after minimally invasive stabilization of intra-articular calcaneal fractures, including the return-to-sports rate.

PATIENTS AND METHODS

 Patients with minimally invasive stabilization of intra-articular calcaneal fractures were collected from the database of a Level I trauma center and evaluated in a retrospective and explorative way. The clinical and radiological examination have been done immediately after the operation, after 2 and 6 weeks postoperative and after a minimum follow-up of 2 years. Clinical and radiological examination was performed by applying the American Orthopedic Foot and Ankle Society hindfoot scale score (AOFAS), 36-item Short Form Health Survey (SF-36), the Tegner Activity Scale, the Foot and Ankle Outcome Score (FAOS) and with a questionnaire about pre- and postoperative engagement in sport and recreational activities.

RESULTS

 Fourty-nine patients with an isolated uni-lateral fracture of the calcaneus who fulfilled all inclusion criteria were assessed. Fourty-two of them were male and 24 were under the age of 50 years. No statistically significant differences were noted between Sanders I/II and Sanders III/IV in terms of SF-36, AOFAS, FAOS or Tegner-scale. A less satisfying result was noticed in Sanders III/IV patients. General health, pain in FAOS, physical functioning and pain in SF-36 were strongly dependent on Tegner score values. Twenty-nine percent of our study population changed sport activities after injury, whereas 22 percent stopped all kinds of sports. Consequently, our overall return-to-sport rate was 78 percent.

CONCLUSION

 Clinical results including different scores and quality of life parameters in our study population were satisfying. About 80 percent of patients could return to sports, but there are still many patients that were not able to perform sports and physical activities on the same level as before.

Surgical experience as a decisive factor for the outcome of calcaneal fractures using locking compression plate: results of 3 years

INTRODUCTION

Calcaneal fractures account for 60-75% of all tarsal fractures and represent surgical challenges because of their frequency and complexity. Despite standardized procedures and new implants, literature reports high revision rates and unsatisfactory results. The study aims to describe the role of the surgeon with respect to the clinical outcome.

METHODS

Between 2014 and 2017, 94 calcaneal fractures (all type AO C1-3) were re-examined in 86 patients (67 male and 19 female; mean age: 51 years). The treatment was always carried out by means of locking compression plate via the extensile lateral approach. A comparison was made between treatment by an experienced (ES) and less experienced surgeon (LES). Annually, the ES performed at least 30 procedures for calcaneus fracture treatment as compared to < 10 operations performed by the LES.

RESULTS

The mean AOFAS, VAS FA, and Kiel Score in the ES group were 77.0 (SD 15.9), 69.0 (SD 18.8), and 65.0 (SD 20.6), respectively. The corresponding values in the LES group were 68.1 (SD 21.0), 60.3 (SD 22.4), and 53.0 (SD 21.9) (p < 0.05). The operation time was on average 14 min shorter in the ES group than the LES group (p < 0.05).

CONCLUSION

The significantly better scores, along with shorter operation time, shorter duration of incapacity to work, and lower complication rate prove the importance of having an experienced surgeon perform complex intra-articular calcaneal fracture repairs. The extensile lateral approach is still considered the standard method.

LEVEL OF EVIDENCE

Level III, comparative series.

Outcome of Minimally Invasive Osteosynthesis for Displaced Intra-articular Calcaneal Fractures Using Cannulated Screws: A Prospective Case Series

This prospective study sought to assess the functional and radiological outcomes of minimally invasive osteosynthesis using cannulated screws and to examine the effect of different parameters on the functional outcome. The Maryland foot score and the visual analog scale of pain were used to assess the functional outcomes and postoperative patient's satisfaction rate. Preoperative and postoperative Böhler's angle, angle of Gissane, calcaneal width, and height, were compared. The study included 46 fractures in 40 patients; 38 (95%) males and 2 (5%) females with a mean age of 34.8 ± 3 years. The mean time lapse to surgery was 3.2 ± 2.1 days. The mean duration of surgery was 39.8 ± 9.3 minutes. The mean follow-up period was 29.2 months. At final follow-up, the mean Maryland foot score was 85 ± 6.3. Satisfactory results were achieved in 91.3% of fractures, while unsatisfactory in 8.7%. The mean visual analog scale score of pain decreased from 7.3 ± 05 preoperatively to 1.2 ± 0.7 at the final follow-up, p <.001. Postoperatively, there was significant improvement of Böhler's angle, angle of Gissane, calcaneal width, and height, p < .001. Factors associated with better functional outcomes included reduced time lapse to surgery, p = .032, and more accurate restoration of the calcaneal parameters. Management of intra-articular calcaneal fractures by minimally invasive osteosynthesis using cannulated screws can achieve satisfactory functional and radiological outcomes. Better outcomes are associated with reduced time lapse to surgery, and accurate reduction and restoration of calcaneal angles, height, and width.

Clinical and Radiological Outcomes of Minimally Invasive Reduction and Percutaneous K-wire Fixation for Intra-articular Calcaneal Fractures

There has been much controversy over the optimal operative treatment of intra-articular calcaneal fractures. Open reduction and internal fixation is associated with a high incidence of postoperative soft tissue complications. This study sought to evaluate the outcomes of indirect reduction and percutaneous K-wire fixation for displaced intra-articular calcaneal fractures. This was a prospective study of 40 consecutive patients with 44 Sanders type II or III intra-articular calcaneal fractures who had undergone closed or mini-open reduction and percutaneous K-wire fixation from 2013 to 2016. The Maryland Foot Score and visual analog scale score for pain were used to assess functional outcomes and postoperative patient satisfaction. Twenty-two patients were men and 18 patients were women, with a mean age of 34.5 years. According to the Sanders classification, 26 fractures were type II and 18 were type III. Mean follow-up was 31.9 months. The clinical outcome was satisfactory for 36 fractures (81.8%) and unsatisfactory for 8 fractures (18.2%). Mean time of radiological union was 8.7 weeks. Mean full weight-bearing time was 13 weeks. Mean visual analog scale score was 1.4 when radiographic fracture healing was detected. Repeated follow-up radiographs showed no loss of reduction or collapse of the posterior facet. Closed or mini-open reduction and percutaneous K-wire fixation of Sanders type II or III calcaneal fractures has excellent functional outcomes with minimal soft tissue complications. [Orthopedics. 2020; 43(2): 97-101.].

Calcaneal Fractures - Should We or Should We not Operate?

The best treatment for displaced, intraarticular fractures of the calcaneum remains controversial. Surgical treatment of these injuries is challenging and have a considerable learning curve. Studies comparing operative with nonoperative treatment including randomized trials and meta-analyses are fraught with a considerable number of confounders including highly variable fracture patterns, soft-tissue conditions, patient characteristics, surgeon experience, limited sensitivity of outcome measures, and rehabilitation protocols. It has become apparent that there is no single treatment that is suitable for all calcaneal fractures. Treatment should be tailored to the individual fracture pathoanatomy, accompanying soft-tissue damage, associated injuries, functional demand, and comorbidities of the patient. If operative treatment is chosen, reconstruction of the overall shape of the calcaneum and joint surfaces are of utmost importance to obtain a good functional result. Despite meticulous reconstruction, primary cartilage damage due to the impact at the time of injury may lead to posttraumatic subtalar arthritis. Even if subtalar fusion becomes necessary, patients benefit from primary anatomical reconstruction of the hindfoot geometry because in situ fusion is easier to perform and associated with better results than corrective fusion for hindfoot deformities in malunited calcaneal fractures. To minimize wound healing problems and stiffness due to scar formation after open reduction and internal fixation (ORIF) through extensile approaches several percutaneous and less invasive procedures through a direct approach over the sinus tarsi have successfully lowered the rates of infections and wound complications while ensuring exact anatomic reduction. There is evidence from multiple studies that malunited displaced calcaneal fractures result in painful arthritis and disabling, three-dimensional foot deformities for the affected patients. The poorest treatment results are reported after open surgical treatment that failed to achieve anatomic reconstruction of the calcaneum and its joints, thus combining the disadvantages of operative and nonoperative treatment. The crucial question, therefore, is not only whether to operate or not but also when and how to operate on calcaneal fractures if surgery is decided.

Interlocking Nail Fixation for the Treatment of Displaced Intra-Articular Calcaneal Fractures

Introduction

Less invasive restoration of joint congruity and calcaneal shape in displaced intra-articular calcaneal fractures via a sinus tarsi approach followed by percutaneous internal fixation with an interlocking nail results in a low rate of soft-tissue complications and good short-term outcomes¹ (Video 1).

Indications & Contraindications

Step 1 Patient Placement

Place the patient in the lateral decubitus position, supporting the involved extremity with a soft radiolucent pillow, flex the contralateral knee, check with fluoroscopy before draping, and obtain lateral radiographs.

Step 2 Incision

Use a sinus tarsi approach for control of the articular reduction.

Step 3 Percutaneous Manipulation of the Main Fragments

Percutaneously manipulate the main fragments to facilitate reduction of the main tuberosity fragment toward the sustentacular fragment and subsequent joint reduction.

Step 4 Joint Reduction with Direct Manipulation of the Main Fragments through the Sinus Tarsi Approach

Reduce the joint with direct manipulation of the main fragments through the sinus tarsi approach.

Step 5 Joint Fixation with Screws

Check the congruency of the posterior subtalar joint facet, stabilize the posterior facet with 2 screws, reduce the tuberosity against the joint block and anterior process, and temporarily fix with Kirschner wires.

Step 6 Introduction of the Intramedullary Nail

Make a 10-mm vertical incision below the attachment of the Achilles tendon, direct the guidewire toward the center of the calcaneocuboid joint, place the guidewire centrally within the calcaneal body, ream over the guidewire, and introduce the intramedullary nail with the attached aiming device.

Step 7 Locking of the Nail

Use the aiming device to position the proximal Kirschner wire into the sustentacular fragment, place the nail so that it hits the sustentaculum tali properly, insert a second Kirschner wire through the other hole of the guiding arm, exchange the wires after drilling for locking screws, apply an end cap to extend the length of nail, if needed, and then verify proper reduction and implant position fluoroscopically.

Step 8 Postoperative Management

Manage the patient with continuous passive motion and active range-of-motion exercises of the ankle beginning on postoperative day 2 and allow partial weight-bearing of 20 kg for 6 to 10 weeks.

Results

Recently, we reported on 103 patients with 106 intra-articular calcaneal fractures treated with the C-Nail by 4 senior surgeons from February 2011 to October 2013¹.

Pitfalls & Challenges

Normative size of the osseous part of calcaneal bursa and its comparison with other calcaneal articular areas

The retro-calcaneal bursa presents a synovial and a non-synovial osseous part of variable dimensions. Studies objectively measuring the variability of the size of this osseous bursal surface cannot be found in literature. The objective of this study was to investigate (i) the dimension variability of the bony part of the bursa and (ii) the relationship of this surface to other articulating areas of the calcaneus. A digital planimeter was used to measure the bursae (n=86) and other articular surface areas of the calcaneus and statistically compared with ANOVA and correlation estimations. The osseous area measured 1.12 (±0.55) cm2, with only the superior articulating area demonstrating a weak correlation to this osseous surface. The osseous area presents a weak correlation with the axial articulating area of the calcaneus. Information on the size of the bony bursa may help safe excision of retrocalcaneal exostoses and in Achille's tendon repair around the posterior tuberosity.

[New techniques in the operative treatment of calcaneal fractures]

The ideal treatment of displaced intra-articular calcaneal fractures is still controversially discussed. Because of the variable fracture patterns and the vulnerable soft tissue coverage an individual treatment concept is advisable. In order to minimize wound edge necrosis associated with extended lateral approaches, selected fractures may be treated percutaneously or in a less invasive manner while controlling joint reduction via a sinus tarsi approach. Fixation in these cases is achieved with screws, intramedullary locking nails or modified plates that are slid in subcutaneously. A thorough knowledge of the three dimensional calcaneal anatomy and open reduction maneuvers is a prerequisite for good results with less invasive techniques. Early functional follow-up treatment aims at early rehabilitation independent of the kind of fixation. Peripheral fractures of the talus and calcaneus frequently result from subluxation and dislocation at the subtalar and Chopart joints. They are still regularly overlooked and result in painful arthritis if left untreated. If an exact anatomical reduction of these intra-articular fractures is impossible, resection of small fragments is indicated.

A Protocol for Percutaneous Transarticular Fixation of Sanders Type II and III Calcaneal Fractures With or Without an Added Mini-Open Approach

Intra-articular fracture of the calcaneus is one of the most displeasing fractures if not properly managed. Open reduction and internal fixation have been associated with a high incidence of postoperative soft tissue complications. Closed reduction and percutaneous fixation have resulted in a greater incidence of postoperative subtalar osteoarthritis with improper reduction of the articular surface. In the present study, a mini-open approach was used in cases of failure of articular surface restoration with closed reduction. A total of 64 feet in 57 consecutive patients with an intra-articular calcaneal fracture underwent the proposed minimally invasive surgical protocol. Of the 57 patients, 7 (12.3%) had bilateral fractures. According to Sanders classification, 33 (51.6%) fractures were type II and 31 (48.4%) were type III. Seven (12.3%) patients had wedge fractures of the dorsolumbar spine without neurologic manifestations. The postoperative evaluation included radiographs and completion of the Maryland Foot Score and visual analog scale for pain. The mean follow-up period was 16 (range 12 to 36) months. The mean operative time was 42 (range 35 to 60) minutes. The mean period until union of the fracture was 12 (range 10 to 16) weeks. The clinical results according to the Maryland Foot Score revealed 52 (81%) with satisfactory (27 excellent and 25 good) and 12 (19%) with unsatisfactory (10 fair and 2 poor) results. The mean visual analog scale score was 1.5 ± 0.3 when radiographic fracture healing was observed. Six patients (9.4%) developed superficial pin tract infections that responded to local care and parenteral antibiotic therapy and resolved completely after removal of the Kirschner wires. In conclusion, the presented surgical protocol combining closed reduction with or without an added mini-open approach and percutaneous fixation improves the functional outcome and minimizes the incidence of complications.

Introduction of a New Locking Nail for Treatment of Intraarticular Calcaneal Fractures

OBJECTIVES

To reduce the complication rate associated with open reduction and internal fixation of displaced intraarticular calcaneal fractures through extensile approaches, a locking nail system (C-Nail) was developed for internal fixation.

DESIGN

Prospective case-control study.

SETTING

Two level I trauma centers (university hospital) and 1 large regional hospital in the Czech Republic and Germany.

PATIENTS

One hundred three patients (89 male and 14 female; mean age, 45.6 years) with 106 calcaneal fractures were treated between February 2011 and October 2013.

INTERVENTION

In all 106 cases, the stainless steel C-Nail with a length of 65 mm, a diameter of 8 mm, and 7 locking options was used for internal fixation. Previous reduction of the posterior facet was performed in 15 cases percutaneously, assisted by arthroscopy and fluoroscopy, and in 91 cases by a sinus tarsi approach. The reduced joint surface was fixed by 1 or 2 compression screws. All other fragments were fixed after reduction and temporary K-wire fixation with the C-Nail introduced percutaneously through the tuberosity and 5 to 6 interlocking screws. The latter were introduced into the sustentacular, the tuberosity, and the anterior process fragments with an aiming device consisting of 3 arms.

MAIN OUTCOME MEASURES

Patients were assessed for complications, restoration of Böhler angle, posterior facet reduction with postoperative computed tomography, and weight-bearing radiographs at 6 months. Functional outcome was assessed using the American Orthopaedic Foot & Ankle Society (AOFAS) ankle/hindfoot scale after 6 and 12 months for all patients.

RESULTS

Wound edge necrosis was seen in 2 cases (1.9%), and soft tissue infection was observed in 1 case (0.9%). Böhler angle improved from 7.3 degree preoperatively to 28.7 degree at 6 months. The posterior facet step-off was reduced from 5.3 mm preoperatively to 0.7 mm postoperatively. The average AOFAS score averaged 89.5 at 6-month and 92.6 at 12-month follow-up.

CONCLUSIONS

The C-Nail is a new locking system for treatment of displaced intraarticular calcaneal fractures combining a primary stability with reduced soft tissue complications.

LEVEL OF EVIDENCE

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

Predicting loss of height in surgically treated displaced intra-articular fractures of the calcaneus

PURPOSE

The goal of calcaneal fracture surgery is to restore its anatomy and good foot function. However, loss of height of the subtalar joint can occur post-operatively, as expressed by a decrease in Böhler's angle (BA). The aim of this study was to identify potential factors associated with a post-operative decrease in BA.

METHODS

All consecutive adult patients treated with open reduction and internal fixation (ORIF) by an extended lateral approach (ELA) between 2000 and 2013 were retrospectively included. Primary outcome was the occurrence of a calcaneal collapse, defined as a postoperative decrease of ≥10° in BA. The BA was measured pre-operatively, directly following surgery and at one year follow-up. Patient characteristics (body mass index, diabetes mellitus, smoking/alcohol/substance abuse, American Society of Anaesthesiologist classification), fracture classification and treatment characteristics: per-operative increase in BA and occurrence of post-operative wound infection (POWI) were collected.

RESULTS

A total of 262 patients with 276 calcaneal fractures were included. A calcaneal collapse occurred in 46 cases (17%). The median preoperative BA, per-operative increase in BA and post-operative decrease in BA were, respectively, 2°, 27° and 4°. A calcaneal collapse was seen more often following a per-operative increase of >25° in BA, but no significant association was found (p = 0.056). Uni- and multivariate analysis showed that patients with substance abuse and those with POWI had significantly more calcaneal collapse (p < 0.05). No association was found between substance abuse and the occurrence of POWI (p = 0.293).

CONCLUSIONS

In nearly one in six patients with an intra-articular calcaneal fracture treated with ORIF by an ELA, a post-operative collapse of ≥10° was found during follow-up. Calcaneal collapse was correlated with the occurrence of a POWI and substance abuse.

Bionic plate design for calcaneal fracture treatment. A biomechanical analysis and first clinical results

PURPOSE

Calcaneal fracture treatment is challenging. Implant failure is one problem encountered with plate osteosynthesis. Therefore a new "bionic" plate was developed, which imitates the trabecular orientation of the human calcaneus. The aim of this study was to biomechanically test this new plate in comparison to a "standard" calcaneal locking plate and present the first clinical results.

METHODS

Six "bionic" and six "standard" calcaneal plates were biomechanically tested for stability and fatigue using synthetic calcanei. Between 4/2012 and 04/2013 the first ten consecutive patients meeting the inclusion criteria were treated with the novel implant and followed-up clinically and radiologically. The 12-month follow-up results are reported.

RESULTS

The "bionic" plate design showed significantly higher fatigue life (68%), load to failure (100%) and reduced displacement under load (90%) if compared to a "standard" locking plate. No major complications were seen; most notably there was no implant failure and no loss of reduction. Mean AOFAS/hindfoot score was 79 (69-86).

CONCLUSIONS

The novel plate architecture offers higher stability and load tolerance while being more resistant to fatigue. The preliminary clinical results are promising. These findings will have to be proved by larger clinical trials.