Delayed flail chest from osteomyelitis and malnutrition that emerged 3 weeks after blunt chest trauma: a case report

Abstract

We present the case of a victim of a motor vehicle accident in his late 60s who suffered from severe torso injuries. He initially presented with abdominal and chest pain, and underwent emergency laparotomy for hemoperitoneum. After surgery, the patient developed pneumonia and septicemia, which were responsive to antibiotics. The patient was treated with mechanical ventilation in the intensive care unit for approximately 10 days and experienced a severe weight loss of approximately 30%, but slowly recovered without dyspnea. Notably, on hospital day 24, he experienced sudden respiratory distress and flail motion of the chest wall in a general ward. This late presentation of flail chest was attributed to non-union at rib fracture sites, and was likely exacerbated by malnutrition and osteomyelitis. Surgical stabilization of rib fractures and excision of the infected rib were successfully performed. The findings from this case highlight the complexity of managing delayed onset of flail chest. The findings from this case suggest the importance of vigilance for late emerging complications in patients with trauma, even when initial symptoms are absent.

Background

A flail chest is one of the most severe injuries in patients who have experienced blunt chest trauma and is associated with high mortality and morbidity rates.^1–3 The definition of flail chest is generally divided into anatomical and physiological definitions.^4,5 Flail segment refers to the anatomical definition of flail chest, and it involves three or more consecutive segmental rib fractures as identified through radiographic examinations such as computed tomography (CT). ⁵ Flail motion, or paradoxical motion of the chest wall, refers to the physiological definition of flail chest and can be observed in patients with flail segments, especially in those with severe injuries.^6,7 Flail motion results in an increased work of breathing, which can lead to respiratory failure. ⁶ However, the diagnosis of flail motion can be delayed in scenarios where mechanical ventilation is applied, rendering spontaneous breathing assessment impossible, or when concomitant brain injuries are present.^6–8 Additionally, the severity of initially observed rib fractures can worsen in the days following the injury, leading to a delayed onset of flail motion. ⁹ Although flail chest may not be detected early, in most cases, it is diagnosed within a few days after the injury.^8,10

We present the case of a patient with multiple torso injuries in whom sudden onset of respiratory distress and severe flail motion of the chest wall were observed 3 weeks after the injury occurred.

Case presentation

A male patient in his late 60s who was involved in a motor vehicle accident presented to a trauma center with severe abdominal and chest pain. The patient was trapped for approximately 20 minutes between the steering wheel and the driver’s seat during the accident. His medical and family histories were unremarkable. He was hemodynamically unstable, with a blood pressure of 85/61 mmHg and a heart rate of 110 beats/minute. The patient was tachypneic, but did not complain of breathing difficulties. CT of the abdomen and chest showed extensive hemoperitoneum and multiple bilateral rib fractures without hemopneumothorax (Figure 1). Immediately after the initial evaluation, the patient’s condition deteriorated, and we decided to perform an emergency exploratory laparotomy.

Figure 1.

Initial radiographic and computed tomographic images. (a) Chest radiograph showing multiple rib fractures on the right chest wall (indicated by the red arrow). (b) Computed tomographic image of the left chest wall displaying a fractured and protruded seventh rib and (c) computed tomographic visualization of an injury to the gastroduodenal artery with active bleeding (indicated by the red arrow) and angulation of the chest wall due to a seventh rib fracture (indicated by the white arrow).

Emergency laparotomy on the day of admission showed active bleeding in the left gastric and gastroduodenal arteries, multiple liver lacerations, and a grade 2 pancreatic head injury. The left gastric and gastroduodenal arteries were successfully ligated with 3-0 black silk. We achieved hemostasis by performing perihepatic packing with surgical pads owing to the patient's hemodynamic instability. Subsequently, we decided to perform open abdominal management and finished the surgery. The patient underwent a second abdominal surgery 28 hours after the first surgery. During this procedure, we identified and ligated bleeding from small branches of the gastroduodenal artery near the pancreatic head using 3-0 black silk. Further hemostasis was achieved with Oxidized Regenerated Cellulose (Surgicel™, Ethicon Inc., Raritan, NJ, USA) and a fibrin sealant (Tisseel™, Baxter Healthcare Corporation Deerfield, IL, USA). We were able to successfully close the abdominal wound.

The patient was extubated on hospital day (HD) 4; however, postoperative care was complicated by delirium. We used quetiapine tablets and intermittent intravenous injections of haloperidol to manage the patient’s delirium, but we could not achieve complete control. Subsequently, the patient was diagnosed with septicemia and pneumonia caused by methicillin–resistant Staphylococcus aureus (MRSA), leading to a worsening condition. After consulting with an infectious disease medicine specialist, we administered intravenous vancomycin 1 g every 12 hours and meropenem 1 g every 8 hours. Despite appropriate antibiotic use, the patient was re-intubated on HD 8 because of pneumonia. After the administration of antibiotics, the patient showed gradual improvement. He underwent closed thoracostomy on the left chest on HD 11 owing to parapneumonic pleural effusion and was extubated again on HD 12 (Supplementary Figure 1). However, MRSA bacteremia continued to be detected in blood cultures. We performed a transesophageal echocardiography under the consultative guidance of the infectious disease medicine specialist, but failed to identify the origin of the MRSA infection. On HD 21, reddish, protruding skin lesions were observed at the bilateral lower costal margins. The patient was still taking antibiotics including vancomycin, and showed cachexia due to malnutrition. Therefore, the medical team overlooked the lesions and considered them a minor symptom similar to contact dermatitis. The patient’s body mass index, which was 23.9 kg/m² (165 cm/65 kg) before the injury, decreased to 15.4 kg/m² (165 cm/42 kg) because of prolonged intensive care treatment. Additionally, he was bedridden despite scheduled nutritional support via nasogastric enteral feeding and parenteral support. On HD 22, the patient’s oxygen saturation level exceeded 95% in room air, and he was able to ambulate using a wheelchair.

On HD 24, the patient suddenly complained of dyspnea, and his oxygen saturation dropped to 79%. The patient showed obvious flail motion of the chest wall, which had not been previously observed (Supplementary Video 1). Chest radiography revealed moderate pleural effusion in the right chest.

To alleviate the patient’s dyspnea, a drainage thoracic catheter was inserted into the right chest. However, his symptoms did not greatly improve, and he was immediately transferred to the intensive care unit and intubated. The medical team planned surgical stabilization of the rib fractures (SSRF) following bilateral anterior thoracotomy in the supine position. Under general anesthesia, using a single-lumen endotracheal tube, the surgeon first examined a reddish lesion on the left chest. Upon incision, pus gushed out, which showed that the fractured ninth rib was in a non-union state, with both ends almost dissolved, suggesting osteomyelitis (Figure 2a). The abscess was connected to the thoracic cavity, and the empyema sac was confined to the costophrenic angle. The incision was sufficiently extended to remove the empyema peel covering the diaphragm. The thoracic cavity was then massively irrigated with saline, and empyemectomy was performed. Another incision was made in the fifth intercostal space, where we found that the fourth and fifth ribs had undergone callus formation but were in non-union, resulting in pseudarthrosis and instability. After callus removal, SSRF was performed on the fourth and fifth ribs. Using a bone cutter, we decided to excise approximately 3 cm from the distal end of the seventh rib, where osteomyelitis was suspected (Figure 2b). Another incision was made in the sixth intercostal space of the right chest. Although osteomyelitis was not observed on the left side, we confirmed the occurrence of pseudarthrosis with callus formation. After callus removal, SSRF was performed on the fifth to eighth ribs, and culture studies were conducted on the excised bone, pus, and empyema (Figure 3). The cultures obtained during surgery showed MRSA.

Figure 2.

Intraoperative photographs of the left chest. (a) As soon as a skin incision was made over the protruded lesion, the distal end of the fractured seventh rib was exposed, and pus was drained (indicated by the white arrow). The abscess is connected to the thoracic cavity (indicated by the black arrow) and (b) photograph of rib excision using a bone cutter following empyemectomy on an area suspected of being osteomyelitis (indicated by the black arrow).

Figure 3.

Immediate postoperative chest radiograph. Surgical stabilization of rib fractures was performed on ribs five to eight on the right and ribs four to five on the left.

The patient underwent tracheostomy on HD 30 and was hospitalized for approximately 2 more months for rehabilitation and nutritional support. After the chest surgery, MRSA was no longer detected. The tracheostomy tube was removed on HD 70, and the patient is currently undergoing outpatient follow-up without any considerable disability (Supplementary Figure 2).

This case was reported according to the CARE guidelines. ¹¹

Discussion

A flail chest is diagnosed by the presence of three or more consecutive segmental rib fractures (flail segments) and the resulting flail motion of the chest wall. A recent report showed that flail segment and flail motion had distinct clinical manifestations, and the authors considered that they should be distinguished. ⁶ In this previous study, flail motion of the chest wall represented the most severe type of injury. Additionally, the same authors reported a prediction model for flail motion in patients with flail segments in another study. ⁷ The model included the number of rib fractures (RFX), the number of segmental RFX including 100% displacement, and the presence of the anterior–lateral type of flail segment. In our case, the patient presented with bilateral anterior–anterior flail segments and 11 RFX, with 5 on the right and 6 on the left. Three of these ribs (seventh to ninth ribs on the left) were 100% displaced. According to the prediction model, ⁷ the estimated probability of flail motion was less than 30%. In particular, the patient did not show flail motion from the initial injury up to HD 23. Moreover, on HD 15, after pneumonia and septicemia were controlled with antibiotics, the patient showed a slow but clear improvement in clinical symptoms. Therefore, no medical staff anticipated worsening of thoracic injury until HD 24.

Although several studies have reported delayed-onset flail chest,^8,10 reports on this condition emerging more than 2 weeks after injury are extremely rare. Generally, when fractures occur because of trauma or other causes, the bone healing process progresses through phases of inflammation, repair, and remodeling.^12–14 Nutritional support is also a crucial factor in bone healing. ¹⁵ Therefore, most patients with fractures in hospital receive appropriate dietary management under the care of medical professionals. Similarly, in the case of RFX, callus formation occurs at the site of the fracture 2 weeks after the injury, providing stability to the chest wall.^12,16 Therefore, in patients with blunt chest trauma, conservative treatment, such as pain control, is usually prioritized unless there is respiratory distress due to flail motion or intrathoracic organ injury caused by RFX. However, in our case, the patient remained bedridden for an extended period, was dependent on a mechanical ventilator, and experienced considerable weight loss owing to malnutrition. Additionally, osteomyelitis was observed at the RFX site, and this was thought to be due to septicemia and pneumonia. This situation led to non-union, and on HD 24, obvious flail motion of the chest wall was observed.

Indications for SSRF remain controversial. However, several randomized studies have shown fair outcomes with SSRF in patients with flail motion accompanied by respiratory distress.^17–19 Additionally, a recent study showed that SSRF provided superior treatment outcomes compared with conservative treatment in patients with non–flail chest with displaced RFX. ²⁰ In this previous study, the authors reported a considerable benefit on the pain scale when SSRF was performed within 72 hours of injury. However, in our case, the patient’s abdominal injuries were the foremost priority to address, and before HD 24, the patient did not show respiratory distress due to multiple bilateral RFX. Therefore, the medical team did not initially consider SSRF.

There are no clear guidelines for hardware-based internal fixation in patients with systemic bacteremia, but most physicians are hesitant to perform internal fixation in patients with uncontrolled infections. Although Large et al. suggested that internal fixation in patients with systemic infection or fever may not pose a major problem, the sample size was not sufficient. ²¹ Therefore, further studies on this issue are required. In this case, although bacteremia was detected in a blood culture, the patient showed no signs of infection including fever and showed slow clinical improvement. These findings led the medical team to believe that the infection was under control. Additionally, on HD 24, when the patient’s condition suddenly worsened, we only considered SSRF for the flail motion. We did not consider the possibility of empyema necessitans. When we encountered empyema and pus, we decided to proceed with SSRF because the patient was already taking vancomycin and there was no further fallback option for bacterial infection. The patient finally showed an excellent outcome and was safely discharged.

Conclusion

The findings in this case suggest that, even in the absence of initial respiratory distress due to RFX, non-union at the fracture site can occur because of factors, such as systemic bacteremia, malnutrition, and osteomyelitis. This non-union, in turn, can lead to a delayed onset of flail motion and respiratory distress.

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Supplemental material, sj-pdf-2-imr-10.1177_03000605241244990 for Delayed flail chest from osteomyelitis and malnutrition that emerged 3 weeks after blunt chest trauma: a case report by Jin Bong Ye, Jin Young Lee and Junepill Seok in Journal of International Medical Research

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Supplemental material, sj-pdf-3-imr-10.1177_03000605241244990 for Delayed flail chest from osteomyelitis and malnutrition that emerged 3 weeks after blunt chest trauma: a case report by Jin Bong Ye, Jin Young Lee and Junepill Seok in Journal of International Medical Research

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Supplemental material, sj-mp4-4-imr-10.1177_03000605241244990 for Delayed flail chest from osteomyelitis and malnutrition that emerged 3 weeks after blunt chest trauma: a case report by Jin Bong Ye, Jin Young Lee and Junepill Seok in Journal of International Medical Research