A new cable-tie based sternal closure system: description of the device, technique of implantation and first clinical evaluation

Biocompatible Cable Ties Are an Alternative to Metal Stabilizers for Bar Securement During Minimally Invasive Pectus Excavatum Repair

Background: Bar stabilization during minimally invasive pectus excavatum repair (MIRPE) is critical to avoid dislodgement. Multiple techniques are described including stabilizers, wires, and sutures. This retrospective study compared bar movement and outcomes between existing techniques and ZipFix™, a biocompatible cable tie. Methods: Patients ≤20 years of age who underwent MIRPE with ZipFix between January 2021 and September 2022 were compared with historical controls who underwent repair by same surgeons between January 2018 and December 2020 using stabilizers or polydioxanone suture (PDS). Demographics, clinical details, and outcomes were compared using Kruskal-Wallis and chi-square tests. Results: Of the 116 patients who underwent repair, 45 had bars secured with ZipFix (39%) and 71 (61%) were historical controls (35 stabilizer, 36 PDS). Median (interquartile range) age was 15 (14-16) years and Haller index was 3.9 (3.6-4.5). Nine (8%) patients required two bars. Haller index and use of second bar were comparable between stabilization techniques (P > .05). In total, 49 patients (40%) reported any pain at 1 month and this was similar between stabilization techniques (P = .45). Median bar movement was greater for bars secured with PDS than with ZipFix or stabilizers at 1 month (5.5 versus 2.3 versus 3.3°, P = .010) and last follow-up (6.5 versus 2.1 versus 3.6°, P < .001). One patient whose bar was secured with PDS required revision for dislodgement. Conclusion: Pectus bar stabilization with ZipFix is a safe alternative to metal stabilizers and both techniques are superior to suture stabilization alone. The use of ZipFix may be preferred given its lower cost and ease of use.

Three-dimensional printed pure-titanium implantation for chest wall reconstruction involving the sternum and ribs: a novel approach

Chest wall reconstruction is challenging due to the complex shape and large defect size. The three-dimensional printing technology enables the fabrication of customized implants, and 3D-printed pure-titanium could provide superior mechanical properties to conventional materials. The aim of this study was to evaluate long-term outcomes of patients undergoing chest wall reconstruction with a 3D-printed pure-titanium implant. Between August 2018 and May 2021, 5 patients underwent surgery due to sternal metastasis (n = 3), postoperative sternal wound infection (n = 1) and deformity (n = 1). The customized implant was designed and constructed based on the size and shape of the chest wall defect measured on computed tomography. All patients demonstrated uneventful recovery without complications during the hospital course. During the median follow-up of 20 months, 1 patient underwent revision surgery due to implant breakage, and 1 removed the implant due to trauma-related chest wall infection. One patient died from cancer progression, while 3 patients are alive without any implant-related complications. Chest wall reconstruction using a 3D-printed pure-titanium implant could be a novel alternative for patients with various conditions affecting the sternum and ribs.

FlatWire Sternal Closure System technique for median sternotomy closure

Sternal closure after median sternotomy traditionally uses a stainless steel wire cerclage. Sternal wires are placed through or around the sternum, and the wire ends are twisted together to bring the sternum back together. Complications of this technique include sternal instability, dehiscence, non-union, and increased pain. Compared to traditional wire cerclage, the Figure 8 FlatWire Sternal Closure System has been demonstrated to be stronger and significantly reduce sternal cut-through and postoperative pain. There was no significant difference in hospital length of stay or mean hospitalization cost. Operative time was slightly longer in the FlatWire group, but this difference has been attributed to the learning curve of mastering the FlatWire technique. This article and supplemental video will demonstrate the technique of FlatWire Sternal Closure System. Briefly, the FlatWire is placed around the sternum, and the FlatWire end is fed through the security box. Once all of the wires are placed, the Figure 8 tensioning device is used to tighten each wire through the security box to the appropriate tensile force. Next, the FlatWires are rotated 90 degrees to hold the sternal position temporarily. Once sternal approximation is achieved, each FlatWire is twisted 120 degrees, and any excess length of the FlatWire is clipped.

Novel mesh suture may resist bone cutting seen with wire-based sternal closures

OBJECTIVE

Sternal dehiscence is frequently associated with wire-based closures cutting through fragile bone, allowing sternal motion, separation, and infection. We investigated whether bone cutting could be limited by using a newly available mesh suture with improved force distribution.

METHODS

Five sternal models were closed using 8 interrupted single sternal wires, double sternal wires, braided poly(ethylene terephthalate) sutures, single-wrapped mesh sutures, or double-wrapped mesh sutures. To simulate chest-wall forces, closed sternal models were pulled apart using 1020 N of axial force applied incrementally. Double sternal wire and double-wrapped mesh suture were further compared by closing 3 new models with each material and subjecting these models to cyclic loading cycles, simulating breathing and coughing. Image analysis of needle hole size measured "bone cutting" by each closure material and sternal distraction as a function of force.

RESULTS

All models exhibited maximal separation at the xiphoid. During axial loading, needle hole size increased 7.2% in the double-wrapped mesh suture model and 9.2% in the double-wire model. Single-wrapped mesh suture, single wires, and braided poly(ethylene terephthalate) extended needle hole size by 6.7%, 47.0%, and 168.3% of original size, respectively. The double-wire model resisted sternal distraction best, separating 0.285 cm at the xiphoid. During cyclic loading, mesh suture exhibited significantly less bone cutting (P = .02) than double wire, with comparable levels of sternal separation (P = .07).

CONCLUSIONS

Mesh suture may resist bone cutting seen in sternal wire closure in bone models with comparable distraction to currently used sternal closure methods.

Fast Curing Multifunctional Tissue Adhesives of Sericin-Based Polyurethane-Acrylates for Sternal Closure

The use of wire cerclage after sternal closure is the standard method because of its rigidity and strength. Despite this, they have many disadvantages such as tissue trauma, operator-induced failures, and the risk of infection. To avoid complications during sternotomy and promote tissue regeneration, tissue adhesives should be used in post-surgical treatment. Here, we report a highly biocompatible, biomimetic, biodegradable, antibacterial, and UV-curable polyurethane-acrylate (PU-A) tissue adhesive for sternal closure as a supportive to wire cerclage. In the study, PU-As were synthesized with variable biocompatible monomers, such as silk sericin, polyethylene glycol, dopamine, and an aliphatic isocyanate 4,4'-methylenebis(cyclohexyl isocyanate). The highest adhesion strength was found to be 4322 kPa, and the ex vivo compressive test result was determined as 715 kPa. The adhesive was determined to be highly biocompatible (on L-929 cells), biodegradable, and antibacterial (on Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus bacteria). Finally, after opening the sternum of rats, the adhesive was applied to bond the bones and cured with UV for 5 min. According to the results, there was no visible inflammation in the adhesive groups, while some animals had high inflammation in the cyanoacrylate and wire cerclage groups. These results indicate that the adhesive may be suitable for sternal fixation by preventing the disadvantages of the steel wires and promoting tissue healing.

Novel Nuss Bar Fixation Using ZipFix for Pectus Excavatum

BACKGROUND

Bar displacement is one of the most serious complications following the Nuss procedure for pectus excavatum repair. This paper reports a novel method of bar fixation using ZipFix, a biocompatible cable-tie implant, and shares a series of patients and outcomes.

METHODS

This paper describes the ZipFix stabilisation method and presents a case series of 20 patients with pectus excavatum who underwent the Nuss procedure and ZipFix stabilisation between July 2015 and September 2020.

RESULTS

A total of 34 ZipFixes were implanted in 20 patients. Six (6) patients had one ZipFix placed and 14 patients had two ZipFixes implanted: 13 were bilateral and one patient had two ZipFixes placed on the right. There was one incidence of asymptomatic posterior superior displacement of the right bar. Two (2) patients had wound infections and one patient had a previously placed bar adjusted and secured with a ZipFix. All patients had full correction of their chest wall deformity with no recurrence.

CONCLUSIONS

This case series shows that the use of ZipFix for Nuss bar fixation is feasible using this technique.

Review of Biomechanical Studies and Finite Element Modeling of Sternal Closure Using Bio-Active Adhesives

The most common complication of median sternotomy surgery is sternum re-separation after sternal fixation, which leads to high rates of morbidity and mortality. The adhered sternal fixation technique comprises the wiring fixation technique and the use of bio-adhesives. Adhered sternal fixation techniques have not been extensively studied using finite element analysis, so mechanical testing studies and finite element analysis of sternal fixation will be presented in this review to find the optimum techniques for simulating sternal fixation with adhesives. The optimal wiring technique should enhance bone stability and limit sternal displacement. Bio-adhesives have been proposed to support sternal fixation, as wiring is prone to failure in cases of post-operative problems. The aim of this paper is to review and present the existing numerical and biomechanical sternal fixation studies by reviewing common sternal closure techniques, adhesives for sternal closure, biomechanical modeling of sternal fixation, and finite element modeling of sternal fixation systems. Investigating the physical behavior of 3D sternal fixation models by finite element analysis (FEA) will lower the expense of conducting clinical trials. This indicates that FEA studies of sternal fixation with adhesives are needed to analyze the efficiency of this sternal closure technique virtually.

Zinc-nutrient element based alloys for absorbable wound closure devices fabrication: Current status, challenges, and future prospects

The need for the development of load-bearing, absorbable wound closure devices is driving the research for novel materials that possess both good biodegradability and superior mechanical characteristics. Biodegradable metals (BMs), namely: magnesium (Mg), zinc (Zn) and iron (Fe), which are currently being investigated for absorbable vascular stent and orthopaedic implant applications, are slowly gaining research interest for the fabrication of wound closure devices. The current review presents an overview of the traditional and novel BM-based intracutaneous and transcutaneous wound closure devices, and identifies Zn as a promising substitute for the traditional materials used in the fabrication of absorbable load-bearing sutures, internal staples, and subcuticular staples. In order to further strengthen Zn to be used in highly stressed situations, nutrient elements (NEs), including calcium (Ca), Mg, Fe, and copper (Cu), are identified as promising alloying elements for the strengthening of Zn-based wound closure device material that simultaneously provide potential therapeutic benefit to the wound healing process during implant biodegradation process. The influence of NEs on the fundamental characteristics of biodegradable Zn are reviewed and critically assessed with regard to the mechanical properties and biodegradability requirements of different wound closure devices. The opportunities and challenges in the development of Zn-based wound closure device materials are presented to inspire future research on this rapidly growing field.

Crimped monofilament nylon leader for median sternotomy closure in 10 dogs

OBJECTIVE

To describe and report the outcomes after closure of median sternotomies with crimped monofilament nylon leader (MNL) in dogs.

STUDY DESIGN

Retrospective observational study.

ANIMALS

Dogs (n = 10) that underwent intrathoracic surgery through a median sternotomy approach.

METHODS

The median sternotomy was closed in a peristernal figure eight pattern with crimped MNL. Medical records were reviewed for clinical and histopathological findings and complications. Owners or veterinarians were contacted to collect long-term follow-up information.

RESULTS

The technique was simple, with no intraoperative complications. Postoperative infection was documented in one dog, requiring removal of a single MNL and associated crimp clamp. Delayed healing of the surgical incision in one dog was managed conservatively. No other complications were documented throughout long-term follow-up at a median of 488 days (range, 199-608).

CONCLUSION

Median sternotomies were successfully closed with crimped MNL and were associated with a low complication rate.

CLINICAL SIGNIFICANCE

Crimped MNL represents an alternative method to close median sternotomies in dogs.

Orthopedic Principles to Facilitate Enhanced Recovery After Cardiac Surgery

Enhanced recovery after surgery (ERAS) protocols recognize early postoperative mobilization as a driver of faster postoperative recovery, return to normal activities, and improved long-term patient outcomes. For patients undergoing open cardiac surgery, an opportunity for facilitating earlier mobilization and a return to normal activity lies in the use of improved techniques to stabilize the sternal osteotomy. By following the key orthopedic principles of approximation, compression, and rigid fixation, a more nuanced approach to sternal precaution protocols is possible, which may enable earlier patient mobilization, physical rehabilitation, and recovery.

Use of new cannulated screws for primary sternal closure in high risk patients for sternal dehiscence

Background

Median sternotomy is still the approach of choice for heart surgery and the most common sternal closure is conventional six-wire technique. Mediastinitis is the frightening complication of the median sternotomy and occurs from 1% up to 2.4% of cases with a mortality rate which ranges from 14% up to 47%. Many methods have been suggested to reinforce the sternum with the common goal to improve sternal stability and prevent mediastinitis, but there is not consensus among cardiac surgeons on the optimal way to close the sternum. For this reason, we report our experience with a sternal device that, although not entirely new as a concept, has new technical features and plays a new role in preventing sternal dehiscence, according to the most recent findings on mechanism which leads to sternal dehiscence.

Methods

We enrolled 62 high risk patients for sternal dehiscence (patients with 2 well established historical risk factors), and we closed the sternum of the patients with a new surgical option consisting of passing, in a conventional six-wire sternal closure, the last sixth steel wire (Ø 1.0 mm, n° 5) through a couple of titanium cannulated screws (Ø 5.5 mm, self-tap-ping with a length from 10 to 16 mm and 2-mm increments) inserted into the 5th or 6th couple of rib cartilages.

Results

Primary chest closure with cannulated screws was performed on 48 males and 14 females. The average age of patients was 67.6 years (range, 43-88 years). The average follow-up was 12.8±16.2 months (range, 1-41 months). Chronic obstructive pulmonary disease (COPD) was the most common preoperative risk factor. The average number of risk factors was 2.4 (range, 2-4). Coronary artery bypass grafting (CABG) was the most common cardiac procedure. There were no peri-operative deaths. BMI >30 Kg/m² and diabetes were the associated of risk factors predisposing to superficial skin dehiscence.

Conclusions

In our clinical experience with high risk patients, this surgical option suggests that there is evidence of an effective stabilization of standard sternal closure and this option seems a promising technique to prevent the domino effect which starts from the xifoid bone and proceeds to the manubrium with the effect of leading to sternal instability which is the first step to mediastinitis.

A Simple Modification of the Conventional Figure-of-Eight Sternal Closure Technique

Objective

To describe a new technique of sternal closure, modified from the conventional figure-of-eight approach, which can provide a secure closure and prevent sternal complications.

Methods

The modified technique is based on the intercalation of the caudal portion of each steel wire passed along the sternum. This is a retrospective analysis of patients operated with this modified technique at our institution between January 2014 and December 2016.

Results

One hundred and forty-three patients underwent sternal closure with the modified technique. In-hospital mortality rate was 1.4% (n=2). No sternal instability was observed at 30 days postoperatively. Two patients developed mediastinitis that required extraction of the wires.

Conclusion

Short-term results have shown that the modified sternal closure technique can be used safely and effectively, with complications rates being consistent with worldwide experience.

ZipFix Versus Conventional Sternal Closure: One-Year Follow-Up

BACKGROUND

The present study aimed to compare postoperative complications commonly revealed after sternotomy closure by new sternal ZipFix™ (Synthes GmbH, Oberdorf, Switzerland) implant and conventional steel wire.

METHODS

Among the initial 360 subjects, 326 patients enrolled in this randomised control trial who were candidates for cardiac surgery from April 2014 to March 2015. After the surgery, the sternal closure was randomly done with poly-ether-ether-ketone (PEEK) based sternal ZipFix (ZF) on the sternal body (n=168) or with conventional wires (CWs) (n=158). Patients were followed postoperatively as well as 1, 3, 6, and 12 months after discharge regarding postoperative complications such as pain severity, dehiscence, and infection including incisional infections (superficial or deep), and organ/space infection (mediastinitis or osteomyelitis).

RESULTS

The mean age of the ZF and CW groups were 63.58±10.9 and 62.42±7.1years, respectively (p=0.262). In addition, there was no significant difference between the two groups' baseline characteristics (p>0.05). Our study showed higher mean pain severity score in the conventional closure group compared with ZipFix closure group at all study time points (p<0.001). Infection was seen in 2.76% of the overall participants with no significant difference of incisional and organ infection between the two groups throughout the study. After 1-month follow-up, five patients in the CW group had sternal dehiscence whereas no patients in ZF had dehiscence (p<0.001).

CONCLUSIONS

Our trial demonstrates greater clinical advantages in terms of pain and sternal dehiscence post surgery by using sternal ZipFix compared to conventional steel wire.

Sternal Closure With Tie Bands: A Word of Caution

The median sternotomy for cardiac operations can be reapproximated in a variety of ways. Traditionally, sternal wires have been used in several configurations to afford satisfactory closure. Alternative techniques include cables, plates, and clip-like devices. A relatively recent addition to the menu of options is the plastic tie band. Although a few studies have suggested its efficacy, this favorable experience has not been universal. The purpose of this report is to describe a failure in closure and the reaction of the soft tissue around it.

Polyetheretherketone (PEEK) for medical applications

Polyetheretherketone (PEEK) is a polyaromatic semi-crystalline thermoplastic polymer with mechanical properties favorable for bio-medical applications. Polyetheretherketone forms: PEEK-LT1, PEEK-LT2, and PEEK-LT3 have already been applied in different surgical fields: spine surgery, orthopedic surgery, maxillo-facial surgery etc. Synthesis of PEEK composites broadens the physicochemical and mechanical properties of PEEK materials. To improve their osteoinductive and antimicrobial capabilities, different types of functionalization of PEEK surfaces and changes in PEEK structure were proposed. PEEK based materials are becoming an important group of biomaterials used for bone and cartilage replacement as well as in a large number of diverse medical fields. The current paper describes the structural changes and the surface functionalization of PEEK materials and their most common biomedical applications. The possibility to use these materials in 3D printing process could increase the scientific interest and their future development as well.

Ex Vivo Mechanical Evaluation of a Sternal ZipFix(®) Implant for Prosthetic Laryngoplasty in Horses

OBJECTIVE

To evaluate the properties of a ZipFix(®) (ZipFix) implant in equine laryngeal cartilages.

STUDY DESIGN

Ex vivo biomechanical study.

SAMPLE POPULATION

Equine arytenoid (n=36) and cricoid cartilages (n=18).

METHODS

Suture bites were placed in arytenoid or cricoid cartilages using a ZipFix(®) implant or a single strand of USP 5 braided polyester (TiCron™), and arytenoid and cricoid cartilages were separately subjected to single load to failure (25 N preload) or cyclic loading for 1,000 cycles, followed by single load to failure. Load, distraction, and stiffness were recorded.

RESULTS

Four arytenoid-ZipFix cartilages fractured on implant placement. Under single load, arytenoid-ZipFix (n=9) failed at a greater mean load (359.01 ± 57.98 N) than arytenoid-Ticron (159.11 ± 22.98 N; n=12; P<.001). Arytenoid-ZipFix stiffness (31.32 ± 4.26 N/mm) was significantly greater than arytenoid-Ticron (13.18 ± 2.60 N/mm; P<.001). Cricoid-ZipFix stiffness (20.83 ± 3.37 N/mm) was significantly greater than cricoid-Ticron (13.6 ± 3.82 N/mm; n=6; P=.006). Under cyclic load, arytenoid-ZipFix distraction (2.53 ± 0.63 mm; n=5) was significantly less than arytenoid-Ticron (5.06 ± 1.37 mm; n=6, P=.006). After cyclic load, arytenoid-ZipFix failure load (295.16 ± 54.95 N) was significantly greater than arytenoid-Ticron (127.69 ± 32.67 N; P=.002). Arytenoid-ZipFix stiffness (35.59 ± 1.58 N/mm) was significantly greater than arytenoid-Ticron (24.10 ± 6.85 N/mm; P=.019).

CONCLUSION

In arytenoid cartilages, the sternal ZipFix(®) implant was significantly stronger and stiffer compared to a single strand of Ticron. During placement of the ZipFix(®) implant, frequent arytenoid cartilage failure occurred before testing, suggesting the implant is not suitable for clinical application.

Reduction in deep sternal wound infection with use of a peristernal cable-tie closure system: a retrospective case series

Background

Deep sternal wound infections are a rare but serious complication after median sternotomy. We evaluated the incidence of deep sternal wound infection associated with two techniques for sternal closure.

Methods

In this retrospective case series, we recorded the method of sternal closure in consecutive patients undergoing a variety of cardiothoracic surgical procedures. Sternal closure in the historical control group was performed using trans-sternal, stainless-steel wire sutures; subsequent patients were closed using wire sutures in conjunction with a novel, peristernal cable-tie closure system to reinforce the corpus sterni. Perioperative care was standardized between groups. Demographics, risk factors, and postoperative outcomes were analyzed.

Results

Between July 2010 and July 2014, 609 consecutive adult patients underwent sternal closure following open median sternotomy at a single hospital in Mobile, Alabama. Sternal closure was accomplished with wire sutures in the first 309 patients and with cable-tie reinforcement in the subsequent 300 patients. Baseline characteristics were comparable between groups, except that the cable-tie group exhibited greater preoperative comorbidity. Mean body mass index was comparable between groups (30.2 ± 6.6 kg/m² wire suture versus 30.5 ± 7.7 cable-tie, p = 0.568). Deep sternal wound infection occurred in 2.6 % (8/309) patients in the wire-suture group, whereas no deep sternal wound infections were observed in the cable tie group (p = 0.008).

Conclusions

The peristernal cable-tie system was a simple and reliable method for sternal closure after open median sternotomy, and was associated with a reduced risk of deep sternal wound infection, even in an obese and comorbid population.

In vivo evaluation of a novel mesh suture design for abdominal wall closure

Supplemental Digital Content is available in the text.

Background:

The authors present a novel mesh suture design aimed at minimizing the early laparotomy dehiscence that drives ventral hernia formation. The authors hypothesized that modulation of the suture-tissue interface through use of a macroporous structure and increased aspect ratio (width-to-height ratio) would decrease the suture pull-through that leads to laparotomy dehiscence.

Methods:

Incisional hernias were produced in 30 rats according to an established hernia model. The rat hernias were randomized to repair with either two 5-0 polypropylene sutures or two midweight polypropylene mesh sutures. Standardized photographs were taken before repair and 1 month after repair. Edge-detection software was used to define the border of the hernia defect and calculate the defect area. Histologic analysis was performed on all mesh suture specimens.

Results:

Seventeen hernias were repaired with mesh sutures and 13 were repaired with conventional sutures. The mean area of the recurrent defects following repair with mesh suture was 177.8 ± 27.1 mm2, compared with 267.3 ± 34.1 mm2 following conventional suture repair. This correlated to a 57.4 percent reduction in defect area after mesh suture repair, compared with a 10.1 percent increase in defect area following conventional suture repair (p < 0.0007). None (zero of 34) of the mesh sutures pulled through the surrounding tissue, whereas 65 percent (17 of 26) of the conventional sutures demonstrated complete pull-through. Excellent fibrocollagenous ingrowth was observed in 13 of 17 mesh suture specimens.

Conclusions:

Mesh sutures better resisted suture pull-through than conventional polypropylene sutures. The design elements of mesh sutures may prevent early laparotomy dehiscence by more evenly distributing distracting forces at the suture-tissue interface and permitting tissue incorporation of the suture itself.

Prospective, randomized, single blinded pilot study of a new FlatWire based sternal closure system

Background

Unstable steel wire cerclage following open heart surgery may result in increased pain, sternal cut-through, non-union, or dehiscence. These complications lead to longer hospital stays, increased cost, higher morbidity, and patient dissatisfaction. The Figure 8 FlatWire Sternal Closure System is a new construct which is a simple, intuitive, and inexpensive alternative for primary sternal repair following open heart surgery. Prior bench-top testing of FlatWire has demonstrated superior strength and stiffness compared to traditional steel wire. We present our initial experience in a prospective, randomized, single blinded pilot study utilizing this FDA approved system.

Methods

Sixty-three patients undergoing elective complete sternotomies at a single institution were randomly assigned to receive either the Figure 8 FlatWire or standard steel wire cerclage. All surgeries were performed by a single board certified cardiothoracic surgeon. Data collected included: Age, BMI, pump time, off pump to surgical stop time, length of hospital stay after surgery, cost from time of surgery to discharge, and pain on a visual analog pain scale on the day of discharge, day 30, and day 60.

Results

The groups were well matched. Patients receiving the Figure 8 FlatWire (33) had a reduction in length of stay compared to patients receiving steel wire circlage (30), but it was not statistically significant (6.8 vs. 7.8 days respectively, p < 0.093). Additionally those with the FlatWire reported significantly decreased pain at day of discharge (3.07 vs. 4.92 points on pain scale, p < 0.0066), with similar pain scores at 30 and 60 days. Off pump to surgery stop time was increased by 15.9 minutes in patients receiving the FlatWire vs. steel wires (55.7 vs. 71.6 minutes, p = 0.00025). Mean cost from surgery until discharge was $87,820.98 in the FlatWire group vs. $91,930.29 in the steel wire group (p < 0.3082).

Conclusion

Early clinical results suggest that Figure 8 FlatWire provides excellent stability, which resulted in significantly diminished postoperative pain at discharge. Although not significant there was a trend toward decreased length of stay, and reduced cost. Further clinical research is warranted to expand upon these initial trends and validate long term outcomes.

Sternal closure following negative pressure wound therapy: a safe approach with a new titanium device

BACKGROUND

The application of negative pressure wound therapy (NPWT) in patients with deep wound infection after cardiac surgery has steadily increased worldwide. Following NPWT, in patients with concomitant sternal diastasis, preparation of the substernal structures for the sternal wires application is mandatory, with increased risk of severe complications, such as laceration of the right ventricle. The aim of this study is to present an innovative technique for sternal closure after NPWT, using the ASCS® System (ASCS atraumatic Sternum Closure System; KS Handelsvertretung Produktinovation, Bad Homburg, Germany).

METHODS

Between January 2009 and August 2012, 88 patients (mean age 64.2 ± 12.4 years) with deep wound infection and sternal diastasis received NPWT; 16 of these patients (18.2%) underwent sternal closure after NPWT with ASCS®.

RESULTS

In all 16 cases, neither sub-sternal dissection nor placement of trans- or peristernal wires was necessary. No damage to the aortocoronary bypass and ventricular rupture occurred. Minimal post-operative bleeding from Redon drains (mean 40 ± 10 ml) was present. At follow-up, deep wound infection and sternal diastasis did not occur.

CONCLUSIONS

The ASCS® System combined with NPWT in patients with postoperative deep wound infection and sternal diastasis is a feasible and safe procedure. Because preparation of the substernal structures is not necessary, this device might prevent the occurrence of severe complications. Our experience, however, is limited and larger case series are necessary to fully evaluate this new and innovative technique.

A review of sternal closure techniques

Sternotomy and sternal closure occur prior to and post cardiac surgery, respectively. Although post-operative complications associated with poor sternal fixation can result in morbidity, mortality, and considerable resource utilization, sternotomy is preferred over other methods such as lateral thoracotomy. Rigid sternal fixation is associated with stability and reduced incidence of post-operative complications. This is a comprehensive review of the literature evaluating in vivo, in vitro, and clinical responses to applying commercial and experimental surgical tools for sternal fixation after median sternotomy. Wiring, interlocking, plate-screw, and cementation techniques have been examined for closure, but none have experienced widespread adoption. Although all techniques have their advantages, serious post-operative complications were associated with the use of wiring and/or plating techniques in high-risk patients. A fraction of studies have analyzed the use of sternal interlocking systems and only a single study analyzed the effect of using kryptonite cement with wires. Plating and interlocking techniques are superior to wiring in terms of stability and reduced rate of post-operative complications; however, further clinical studies and long-term follow-up are required. The ideal sternal closure should ensure stability, reduced rate of post-operative complications, and a short hospitalization period, alongside cost-effectiveness.

A new cable-tie-based sternal closure device: infectious considerations

OBJECTIVES

To determine the difference in sternal infection and other infectious events between conventional wire and cable-tie-based closure techniques post-sternotomy in a collective of patients after cardiac surgery.

METHODS

The sternal ZipFix™ (ZF) system consists of a biocompatible poly-ether-ether-ketone (PEEK) cable-tie that surrounds the sternum through the intercostal space and provides a large implant-to-bone contact. Between 1 February 2011 and 31 January 2012, 680 cardiac operations were performed via sternotomy at our institution. After the exclusion of operations for active endocarditis and early mortality within 7 days, 95 patients were exclusively closed with ZF and could be compared with 498 who were closed with conventional wires (CWs) during the same period. A multivariable logistic regression analysis, including body mass index, renal impairment and emergency as suspected confounders and inverse propensity weights was performed on the infection rate.

RESULTS

Total infection rate was 6.1%, with a total of 36 diagnosed sternal infections (5 in ZF and 31 in CW). Comparing ZF with CW with regard to sternal infection, there is no statistically significant difference related to the device (odds ratio: 0.067, confidence interval: 0.04-9.16, P=0.72). The propensity modelling provided excellent overlap and the mean propensity was almost the same in both groups. Thus, we have observed no difference in receiving either ZF or CW. No sternal instability was observed with the ZF device, unlike 4/31 patients in the CW group. The overall operation time is reduced by 11 min in the ZF group with identical perfusion and clamping times.

CONCLUSIONS

Our study underlines a neutral effect of the sternal ZipFix™ system in patients regarding sternal infection. Postoperative complications are similar in both sternal closure methods. The cable-tie-based system is fast, easy to use, reliable and safe.