Sternal osteomyelitis: treatment with rectus abdominis muscle

Free Flap Reconstruction of Sternal Defects after Cardiac Surgery: An Algorithmic Approach for Dealing with Sparse Recipient Vessels

Background

Sparsity of recipient vessels poses a challenge for microsurgical free flap reconstruction of sternal defects following deep sternal wound infection after cardiac surgery.

Methods

From January 2013, a standardized algorithm for dealing with sparse recipient vessels was strictly followed. In this retrospective study including 75 patients, we compared operative details, surgical complications, and reconstructive outcomes of patients treated according to this algorithm (group A: January 2013-May 2021; n = 46) with a historical control group (group B: January 2000-December 2012, n = 29).

Results

The left internal mammary artery had been harvested for arterial bypass grafting in 40 of 46 cases (87%) in group A and in all cases in group B. The right internal mammary artery (RIMA) and right internal mammary vein (RIMV) were the first choice as recipient vessels. In case of unsuitability of the RIMV, a right cephalic vein (CV) turndown was used for venous outflow. If both RIMA and RIMV proved insufficient, a single-stage arterio-venous loop (AVL) between the CV and subclavian artery (CV-SA AVL), CV and thoracoacromial artery (CV-TA AVL), or subclavian artery and subclavian vein (SA-SV AVL) was established. The algorithmic approach significantly reduced partial flap necrosis [group A: n = 3 (7%) versus group b: n = 7 (24%); P = 0.04], and overall operation time [group A: 360 ± 88 min versus group B: 415 ± 80 min; P = 0.01].

Conclusions

Standardized approaches improve clinical outcomes in microsurgical free flap sternal reconstruction after cardiac surgery.

Extended arc of rotation of Latissimus Dorsi Musculocutaneous Flap providing well-vascularized tissue for reconstruction of complete defects of the sternum: An anatomical study of flap pedicle modification

BACKGROUND

Deep sternal wound infections (DSWI) following cardiothoracic surgery represent a life quality endangering sequelae and may lead to sternal osteomyelitis. Radical debridement followed by Negative Pressure Wound Therapy (NPWT) may achieve infection control, provide angiogenesis, and improve respiratory function. When stable wound conditions have been established a sustainable plastic surgical flap reconstruction should be undertaken.

OBJECTIVE

This study analyses a method to simplify defect coverage with a single Latissimus Dorsi Myocutaneous Flap (LDMF).

METHODS

Preparation of 20 LDMF in ten fresh frozen cadavers was conducted. Surgical steps to increase pedicle length were evaluated. The common surgical preparation of LDMF was compared with additional transection of the Circumflex Scapular Artery (CSA).

RESULTS

Alteration of the surgical preparation of LDMF by sacrificing the CSA may provide highly valuable well-vascularized muscle tissue above the sensitive area of the Xiphisternum. All defects could be completely reconstructed with a single LDMF. The gain in length of flap tissue in the inferior third of the sternum was 3.86±0.9 cm (range 2.2 to 8 cm).

CONCLUSIONS

By sacrificing the CSA in harvesting the LDMF a promising gain in length, perfusion and volume may be achieved to cover big sternal defects with a single flap.

Efficacy and safety of pectoralis muscle flap combined rectus abdominis muscle sheath fasciocutaneous flap for reconstruction of sternal infection

Few studies have assessed the efficacy and safety of reconstruction of sternal infection using a pectoralis muscle flap combined with a rectus abdominis muscle (RAM) sheath fasciocutaneous flap. We report here our experience with this procedure to reconstruct the sternal defect in patients (n = 46) with a deep sternal wound infection (DSWI) after cardiac surgery. After wound reconstruction, the proportion of prolonged mechanical ventilation use and intensive care unit (ICU) stay were 17.4% (n = 8) and 21.7% (n = 10), respectively. The 30‐day all‐cause mortality was 15.2%; recurrence rate was 17.4%; postoperative complications were 15.2%; and median hospital stay was 31 (0‐157) days. Multivariate logistic regression analysis revealed that hypertension (β = 21.32, 95%CI 4.955‐37.68, P = .014), drainage‐tube use (β = 0.944, 95%CI 0.273‐1.614, P = .008), and prolonged intensive care unit stay (β = 53.65, 95%CI 31.353‐75.938, P < .001) were significantly correlated with hospital stay. In conclusion, a procedure including surgical debridement, sternal reconstruction with bilateral PM and RAM sheath flap, long‐term antibiotics, and adequate drainage is a beneficial technique in the reconstruction of deep sternal wound infection after cardiac surgery. Duration of drainage tube use may be as an index for a hospital stay or wound healing.

Challenges and Management in Wound Care

SUMMARY

Wounds have been one of the most prominent pathologies since the beginning of humanity. For the last 5 decades, a drastic improvement of healing has been observed, thanks to new medical devices based on fluid aspiration capacities and the development of negative pressure wound therapy. Negative-pressure wound therapy was initially designed for a double action, fluid aspiration and mechanical stimulation of wound edges by a foam. Successive technical evolutions of negative pressure wound therapy were declined since 1997 when Argenta and Morykwas first presented their solution. The adjunct of instillation in 2009 was considered as the first interactive dressing, allowing topical wound solutions to sequentially reach the wound, in alternance with negative pressure. Other devices based on the same principle were designed to prevent postoperative infections when placed over a suture after surgery. This long evolution could enhance the armamentarium of possible solutions, considerably reducing the wound healing time.

Comparison of pedicled versus free flaps for reconstruction of extensive deep sternal wound defects following cardiac surgery: A retrospective study

BACKGROUND

Myocutaneous pedicled flaps are the method of choice for sternal reconstruction after deep sternal wound infection (DSWI) following cardiac surgery. We set out to investigate whether free flaps provide a superior alternative for particularly extended sternal defects.

METHODS

Between October 2008 and February 2020, 86 patients with DSWI underwent sternal reconstruction with myocutaneous flaps at our institution. Patients were retrospectively grouped into pedicled (A; n = 42) and free flaps (B, n = 44). The objective was to compare operative details, outcome variables, surgical as well as medical complication rates between both groups, retrospectively. Binary logistic regression analysis was applied to determine the effect of increasing defect size on flap necrosis.

RESULTS

Rates of partial flap necrosis (>5% of the skin island) were significant higher in pedicled flaps (n = 14), when compared to free flaps (n = 4) (OR: 5.0; 33 vs. 9%; p = .008). Increasing defect size was a significant risk factor for the incidence of partial flap necrosis of pedicled flaps (p = .012), resulting in a significant higher rate of additional surgeries (p = .036). Binary regression model revealed that the relative likelihood of pedicled flap necrosis increased by 2.7% with every extra square-centimeter of defect size.

CONCLUSION

To avoid an increased risk of partial flap necrosis, free flaps expand the limits of extensive sternal defect reconstruction with encouragingly low complication rates and proved to be a superior alternative to pedicled flaps in selected patients.

Reconstruction of Oncologic Sternectomy Defects: Lessons Learned from 60 Cases at a Single Institution

Oncologic sternectomy results in complex defects where preoperative planning is paramount to achieve best reconstructive outcomes. Although pectoralis major muscle flap (PMF) is the workhorse for sternal soft tissue coverage, additional flaps can be required. Our purpose is to evaluate defects in which other flaps beside PMF were required to achieve optimal reconstruction.

Deep sternal wound infection - latissimus dorsi flap is a reliable option for reconstruction of the thoracic wall

Background

At present, data describing patients’ long-term outcomes, quality of life, and survival after deep sternal wound infection are rarely available.

The purpose of our study was to evaluate functional outcome and patient well-being after debridement and reconstruction of the sternal defect using a pedicled latissimus dorsi flap following deep sternal wound infection (DSWI).

Methods

This retrospective analysis reviewed 106 cases of DSWI after open-heart surgery treated between May 1, 2012, and May 31, 2015. The parameters of interest were demographic and medical data, including comorbidity and mortality. Follow-up consisted of physical examination of the patients using a specific shoulder assessment, including strength tests and measurements of pulmonary function.

Results

The population consisted of 69 (65%) male and 37 (35%) female patients. Their average age at the time of plastic surgery was 69 years (range: 35–85). The 30-day mortality was 20% (n = 21); after one-year, mortality was 47% (n = 50), and at follow-up, it was 54% (n = 58).

Heart surgery was elective in 45 cases (42%), urgent in 31 cases (29%) and for emergency reasons in 30 cases (28%). The preoperative European System for Cardiac Operative Risk Evaluation (EuroSCORE) averaged 16.3 (range: 0.88–76.76).

On the dynamometer assessment, a value of 181 Newton (N) (±97) could be achieved on the donor side, in contrast to 205 N (±91) on the contralateral side.

The inspiratory vital capacity of the lung was reduced to an average of 70.58% (range: 26–118), and the forced expiratory volume in 1 s was decreased to an average of 69.85% (range: 38.2–118).

Conclusions

Given that only small adverse effects in shoulder function, strength, and pulmonary function were observed, the latissimus dorsi flap appears to be a safe and reliable option for the reconstruction of the sternal region after DSWI.

Infraareolar pectoralis major myocutaneous island flap as treatment of first choice for deep sternal wound infection

Deep sternal wound infection (DSWI) is a grave complication of median sternotomy, associated with high morbidity, mortality and escalating treatment costs. There is general consensus that optimal treatment comprises radical debridement followed by coverage with a vascularised flap. However, there is ongoing debate regarding the ideal operative procedure. We present our experience with the infraareolar pectoralis major island myocutaneous flap (PEC-MI flap) as treatment of first choice in DSWI. Following a retrospective chart review, data pertaining to patient demographics, type of cardiac surgery performed, prevalence of known DSWI risk factors, identified pathogens, duration of surgery, flap-related complications, duration of hospital stay and antibiotic therapy, as well as mortality were noted. Additionally, we describe the operative technique and review the relevant literature. Twenty-five patients underwent coverage with the PEC-MI flap in our department. The average age was 69.2 years. Nineteen patients underwent coronary artery bypass surgery, 10 valve replacement, two aortic replacement surgery and one pericardiectomy. In six cases, no internal mammary artery was used in cardiac surgery, in 11 cases one and in seven cases both internal mammary arteries were used. The average duration of surgery was 154.2 min and the average hospital stay was 28.4 days. Complications which required revision surgery were haematoma in three cases, one wound dehiscence and one recurrent infection. Two cases required coverage with an additional regional flap. The PEC-MI flap has been used as flap of first choice in our clinic for treatment of DSWI. It is sufficient to raise the flap unilaterally, and it does not require skin grafting. The combination of immunocompetent bulky muscle tissue used to obliterate the sternal cavity and the large skin paddle enabling a low-tension skin closure allows reliable and efficient treatment of this severe complication.

Introduction to chest wall reconstruction: anatomy and physiology of the chest and indications for chest wall reconstruction

The chest wall functions as a protective cage around the vital organs of the body, and significant disruption of its structure can have dire respiratory and circulatory consequences. The past several decades have seen a marked improvement in the management and reconstruction of complex chest wall defects. Widespread acceptance of muscle and musculocutaneous flaps such as the latissimus dorsi, pectoralis major, serratus anterior, and rectus abdominis has led to a sharp decrease in infections and mortality. Successful reconstructions are dependent upon a detailed knowledge of the functional anatomy and blood supply of the chest and the underlying pathophysiology of a particular disease process. This article will provide an overview of key principles and evidence-based approaches to chest wall reconstruction.

Our experience with pectoralis major flap for management of sternal dehiscence: A review of 25 cases

Objective:

To report our experience of the pectoralis major flap as the treatment modality for post coronary artery bypass sternal wound dehiscence.

Materials and Methods:

A retrospective study of 25 open heart surgery cases, performed between January 2006 and December 2010 at Deenanath Mangeshkar Hospital, Pune, was carried out. Unilateral or bilateral pectoralis major muscle flap by the double breasting technique using rectus extension was used in the management of these patients. The outcome was assessed on the basis of efficacy of flap surgery in achieving wound healing and post-surgery shoulder joint movements to evaluate donor site morbidity. The follow-up ranged from 5 months to 3.5 years.

Results:

Twenty-three (92%) patients were discharged with complete wound closure. One patient (4%) had wound dehiscence after flap surgery. One patient (4%) died in the hospital in the immediate postoperative period due to mediastinitis. No recurrent sternum infection has occurred till date in 24 patients (96%). For one patient (4%) who had wound dehiscence, daily dressing was done and wound healing was achieved with secondary intension. At follow-up, shoulder joint movements were normal in all the patients.

Conclusions:

The double breasting technique of the pectoralis major muscle flaps with rectus sheath extension is efficient in covering the entire length of the defect and can reduce the morbidity, without affecting the function of the shoulder joint.

Our experience using the vertical rectus abdominis muscle flap for reconstruction in 12 patients with dehiscence of a median sternotomy wound and mediastinitis

The vertical rectus abdominis (VRAM) flap has been used for reconstruction of sternal defects, particularly in the inferior third, since it was first described 20 years ago. We describe 12 patients with mediastinitis or chronic sternal osteomyelitis after sternotomy treated between 1994 and 1997, nine performed at the Royal Hospitals Trust, London. Sternal osteomyelitis and mediastinitis after median sternotomy is an uncommon (0.4%-8.4%) but often fatal condition. Vascularised pedicles are the treatment of choice, and VRAM flaps were used in all cases. We report good long-term outcome with a follow up of 2-5 years, and no long-term morbidity relating to the VRAM reconstruction. We had only one partial failure of a flap. The operations were largely done in hospitals away from the plastic surgical unit in extremely sick patients, which illustrates the importance of multidisciplinary management to reduce hospital stay, mortality, and morbidity. We argue that early involvement of plastic surgical specialists in the treatment of sternal dehiscence is essential to ensure a successful outcome.

[Plastic surgical reconstruction of extensive thoracic wall defects after oncologic resection]

In defect reconstruction following radical oncologic resection of malignant chest wall tumors, adequate soft-tissue reconstruction must be achieved along with function, stability, integrity, and aesthetics of the chest wall. The purpose of this retrospective analysis was to evaluate the oncoplastic concept following radical resection of malignant chest wall infiltration with an interdisciplinary approach. Between 1999 and 2005, 36 consecutive patients (nine males, 27 females, mean age 55 years, range 20-78) were treated with resection for malignant tumors of the chest wall. Indications were locally recurrent breast carcinoma (patient n=22), thymoma (n=1), and desmoid tumor (n=1). Primary lesions of the chest wall were spinalioma (n=1), sarcoma (n=7), and non-small-cell lung cancer (n=2). There were distant metastases of colon and cervical cancer in one patient each. Soft-tissue reconstruction was carried out using primary closure (n=1), external oblique flap (n=1), pectoralis major myocutaneous flap (n=3), latissimus dorsi myocutaneous flap (n=18), vertical or transversal rectus abdominis myocutaneous flap (n=9), free tensor fascia lata- flap (n=6), trapezius flap (n=1), serratus flap (n=1), and one filet flap. In 15 reconstructive procedures microvascular techniques were used. An average of 3.4 ribs were resected. Stability of the chest wall was obtained with synthetic meshes. The latissimus dorsi flap is considered the flap of choice in chest wall reconstruction. However, alternatives such as pectoralis major flap, VRAM/TRAM flap, free TFL flap, and serratus flap must also be considered. Low mortality and morbidity rates allow tumor resection and chest wall reconstruction even in a palliative setting.

Sternal wound infections following cardiac surgery: risk factor analysis and interdisciplinary treatment

OBJECTIVE

Sternal wound infections are a serious complication after cardiac surgery. Although a variety of treatment algorithms has been published, the ideal operative treatment of complicated median sternotomy wounds is the subject of ongoing controversy.

METHODS

In a retrospective review, 3016 consecutive open-heart surgery patients between January 2003 and June 2006 were evaluated: 65.6% underwent coronary artery bypass surgery (CABG), 16.3% cardiac valve replacement, 13.5% combined CABG and valve replacement, 2.8% aortic reconstruction or replacement, 0.6% artificial heart implantation, and 1.2% cardiac transplantation.

RESULTS

Sixty-three patients (2.1%) developed sternal wound infections. Fifty-six wounds were treated with débridement, irrigation, and re-wiring. Thirty-four patients were treated using vacuum-assisted closure therapy. Nineteen of these patients eventually required plastic surgical coverage with either rectus abdominis or pectoralis major flaps. Diabetes mellitus, rethoracotomy, duration of operation and, interestingly, the time of operation (morning versus afternoon) presented significant risk factors for development of sternal wound infections (P <.05). Three patients developed partial flap necrosis and required a second flap. Eventually, all defects were successfully reconstructed and there was no recurrent ostemyelitis noticed over the entire observation period (follow-up, 23 +/- 13 months).

DISCUSSION

Patients at risk for development of sternal wound infections may be preferably operated in the morning at first position. Vaccuum-assisted closure therapy acts as a link between radical débridement and definitive plastic coverage. The type of flap is individually chosen based on location of the defect and availability of certain vascular axis. The presented interdisciplinary approach with radical surgical débridement, application of subatmospheric pressure dressings, and early involvement of the plastic surgical team allows efficient treatment of infected median sternotomy wounds.

Sternotomy wounds: rectus flap versus modified pectoral reconstruction

BACKGROUND

Infected sternotomy wounds occur in 0.5 to 8.4 percent of open heart operations. They are complex problems, with a mortality rate of 8.1 to 14.8 percent despite flap closure. For closure, the pectoralis major flap has had considerable success. However, in providing coverage to the lower third of the sternum, it may be deficient. Modifications to improve closure have included a rectus flap or an anterior rectus fascia extension to the pectoralis flap.

METHODS

This retrospective study of 130 consecutive sternotomy wounds compares 41 bilateral pectoralis major muscle flaps with a modified anterior rectus fascia extension against 56 rectus abdominis muscle flaps alone in addressing the lower third of the sternum following dehiscence.

RESULTS

Pectoralis flaps with rectus fascia extension and rectus flaps have similar success, postoperative course, and morbidity and mortality rates. The pectoralis flaps with rectus fascia extensions prevented superior dehiscence, but this modification does not eliminate dehiscence of the distal third of the sternum.

CONCLUSIONS

The rectus muscle alone proved superior in coverage to the inferior sternum. Sternal wounds should be covered preferentially by a pectoralis flap to cover a superior infection and by a rectus flap if the dehiscence is localized to the distal third.

Laparoscopic Harvest of an Omental Flap to Reconstruct an Infected Sternotomy Wound

Sternotomy dehiscence is associated with a high mortality rate. In most cases this complication may be treated by simple debridement and antibiotic therapy, but sometimes it is necessary to fill the sternal defect with viable tissue. The greater omentum seems to be the ideal tissue to be transposed because of its malleability, good vascularization, and high lymphatic tissue content. The transposition of the greater omentum usually requires a midline laparotomy for the preparation of the flap, with significant laparotomy-related morbidity. Laparoscopic access may represent an effective alternative for preparing and transposing the omental flap. The key points of the laparoscopic technique are (1) the coloepiploic detachment, (2) the section of the anastomotic arterial branches between the Barkow's arcade and the gastroepiploic arcade, (3) the mobilization of the greater omentum pedicled on the right gastroepiploic artery, and (4) its transposition into the mediastinum, taking care to avoid twisting the gastric greater curvature and the flap itself.

The Role of Anaerobic Bacteria in Mediastinitis

The management of mediastinitis involves directing appropriate antibacterial therapy against the potential bacterial pathogens. The increased recovery of anaerobic bacteria from mediastinal infections has led to a greater appreciation of their role in this condition and to re-evaluation of the proper treatment of this condition. Mediastinitis caused by anaerobic bacteria generally emerges following perforation of the oesophagus, extension of retropharyngeal abscess, suppurative parotitis, cervical cellulitis or abscess of dental origin. The bacteria recovered from these infections are often of oral origin and involve mixed aerobic-anaerobic oral flora. The predominant anaerobic isolates include Bacteroides spp., Peptostreptococcus spp., pigmented Prevotella and Porphyromonas spp. and Fusobacterium spp. Treatment includes surgical intervention, antibacterial therapy and supportive measures. Appropriate management of mediastinal infections due to aerobic and anaerobic infections requires the administration of antibacterials that are effective against both the aerobic and anaerobic components of the infection. Selection of antibacterials for the treatment of mediastinitis is determined by bacteriological studies.

Laparoscopic omental flap for the treatment of major sternal wound infection after cardiac surgery

BACKGROUND

The ideal reconstructive procedure after sternal debridement is still a matter of debate. The omentum might be theoretically preferable for its favorable properties, but it is seldom used because it entails the added trauma of a laparotomy.

METHODS

Three female patients with severe osteomyelitis after myocardial revascularization underwent sternal debridement and filling of the defect with a laparoscopically prepared omental flap. Sternal wound closure was achieved as a single-stage procedure in 2 patients. The third patient had a poststernotomy septicemia and required a 2-stage procedure. The abdominal procedures were conducted through 3 operating 5-mm ports. Omental flaps were developed by complete separation from the transverse colon and lengthening by division of some anastomosing arteries between gastroepiploic vessels and Barkow's arcade. Thoracic transposition of the omentum was achieved through a 5-cm diaphragmatic incision. The flaps were able to reach the base of the neck and fill the sternal defect in all patients.

RESULTS

A smooth postoperative course was observed. Oral intake was started from day 2; sole oral nutrition was maintained from day 3 or 4. Optimal wound healing was observed with minimal or absent local discomfort. Minor transient paradoxical movements of the anterior chest wall disappeared within 1 month. Postoperative hospital stay was 9, 14, and 14 days, respectively.

CONCLUSIONS

Laparoscopic omentoplasty, compared with the open procedure, entails several advantages for the treatment of sternal osteomyelitis. The introduction of minimally invasive techniques may widen the indications for the use of the omentum in the treatment of major sternal wound infections.

A rational approach to wound difficulties after sternotomy: reconstruction and long-term results

One hundred fifty-one patients were reconstructed after median stemotomy by a single plastic surgeon over a 6-year period. The treatment included immediate reconstruction (63 patients) and delayed reconstructions (88 patients). Ninety eight percent of the patients had definitive healing at 6 weeks with an overall 30-day mortality of 4 percent. The issues of long-term intravenous antibiotics, perceived skin deficiency, cardiac decompensation, Candida infections, and reexploration of a healed mediastinum after flap reconstruction are discussed. Follow up (4 months to 6 years) of patients treated with reconstruction compared favorably with patients treated with rewiring procedures (20 patients) in regard to strength, chest wall stability, pulmonary function testing, and functional return to hobbies and employment.

Treatment of infected median sternotomy wounds with a myocutaneous latissimus dorsi muscle flap

Infected sternotomy wounds, particularly if accompanied by osteomyelitis, mediastinitis or pericarditis, are associated with significant morbidity, prolonged hospitalization and a mortality of up to 50%. Until the introduction of muscle flaps, the therapy of choice was debridement and open granulation or catheter irrigation. From 1994 to 1996, 9 patients with infected median sternotomy wounds were treated with a single-stage radical debridement and wound closure with a pedicled myocutaneous latissimus dorsi muscle flap (LDM). One patient received, in addition, a rectus abdominis muscle turnover flap. Healing was uneventful in all cases, with no respiratory complications or chest-wall instability. Shoulder strength was also unaffected. Functional and aesthetic outcome was good. The LDM provides a safe flap with little donor site morbidity. Compared to the most local muscle flaps, an intact IMA is not required. At the same time, length and cost of hospital stay are decreased.

Implantable cardioverter-defibrillator: another device to cover

The implantable cardioverter-defibrillator is a mechanical device developed to manage patients with life-threatening arrhythmias when pharmacologic control has failed or produced unacceptable side effects. It is a significant amount of foreign material with a generator pack (volume 113 to 145 cc, weight 197 to 235 gm) and two or three leads and patches that are inserted into or placed on the heart. Although it has worked very well in preventing premature death, there have been complications associated with the device itself. The most significant of these has been exposure and/or infection. We present three patients who have experienced this problem. Improved coverage has been accomplished by burying the implant beneath the rectus abdominis muscle in situations where skin and subcutaneous tissue alone have proved inadequate. By dividing one or two tendinous inscriptions and the anterior limb of the internal oblique fascia, a musculofascial pocket is created to contain the generator and lead wires. This provided satisfactory coverage in two of our three patients. The single failure resulted from external trauma to the abdominal wall.

Management of the recurrent sternal wound infection

After adequate sternal debridement or resection for the treatment of a sternal wound infection, muscle flap obliteration of the resulting void has become an accepted standard. Unfortunately, recurrence is not an inconsequential risk as evidenced in six (20.7%) of our patients over the last 10 years. Two of these patients required a second muscle flap transfer before obtaining a healed wound. Since the available regional options for appropriate vascularized flaps is limited, especially with the increased frequency in use of the internal mammary artery for coronary artery bypass grafting, great care must be observed in the selection process not just for closure of the initial wound, but in anticipation of untoward sequela. A schema prioritizing alternatives has been established, so as to maximize the benefit of our workhorse flaps, the pectoralis major or rectus abdominis muscles.

The role of the internal thoracic artery in the sternal blood supply

The altered arterial supply to the sternum after use of the internal thoracic artery in coronary bypass surgery was studied by delineation of the sternal arterial system with plastic material and by injection of ink/barium contrast for radiography and microscopy. The study was performed on 17 anterior chest walls from human cadavers. The total arterial supply was charted before and after 'harvest' of the internal thoracic artery. The dominant blood supply to the sternum was found to be periosteal and derived almost exclusively from branches of the internal thoracic artery. Following harvest of that artery, the arterial supply to the upper part of the corpus sterni was compromised, and based only on sparse ramifications to the periosteal membrane from the thoracoacromial artery via branches from the pectoralis major muscle.

Sternotomy after muscle flap repair of sternal osteomyelitis and mediastinitis

A 61-year-old man who had undergone aortocoronary bypass developed sternal osteomyelitis and mediastinitis which required sternal debridement and muscle flap interposition. Two years later the midline incision was used for an orthotopic heart transplantation. No major technical difficulties were encountered at the time of transplantation.