Incidence and factors associated with development of heterotopic ossification after damage control laparotomy

Heterotopic Ossification of the Abdomen: A Rare Sequela Following Trauma and Damage Control Laparotomy

Heterotopic ossification (HO) of the abdomen is a rare yet highly morbid complication following blunt and penetrating trauma requiring damage control laparotomy. We present the case of a 22-year-old man, 20 months after life-threatening motor vehicle crash with major vascular injury requiring multiple abdominal surgeries. The patient was initially treated at a community hospital and subsequently developed a chronic left lower quadrant enterocutaneous fistula, accompanied by a gradually worsening diffuse abdominal pain. He was referred to our tertiary care center with extensive skin breakdown and an inability to control the fistula despite numerous wound care consultations. He also had severe abdominal deformities due to HO in the abdominal wall, peritoneum, paraspinal muscles, and parapelvic regions. As HO is largely underreported, it is crucial to refer those patients, once medically stabilized, to tertiary care centers for surveillance and possible treatment when symptomatic.

A New Antirotation Strategy of K-Wire Tension Band Therapy for Patellar Fracture

Background

Patellar fracture is a common phenomenon observed in orthopedic clinics. Many methods have been shown to be effective in the fixation of patellar fracture. However, there are few studies on the antirotation effect of these methods. The purpose of this study is to present a new strategy of K-wire tension band therapy for patellar fracture and explore the antirotation effect of the modified tension band method on patellar fracture.

Methods

A retrospective clinical observation study was conducted on 75 patients with patellar fracture. Totally, 46 patients were enrolled to the traditional group, who received the traditional K-wire tension band therapy. The modified group included 29 patients on whom our new strategy was implemented. The operation time, intraoperative blood loss, and fracture healing time were collected to compare the two operations and the knee society score (KSS) scores after the operations, and complications were recorded and retrieved to indicate the effectiveness of the two treatments.

Results

The preoperative baseline data (gender, age, fracture types) of the two groups showed no significant statistical difference. Similarly, there was no significant difference in the operation time, intraoperative blood loss, and fracture healing time between the two groups. The KSS clinical scores 1 year after operation was 90 (84, 95) for the traditional group as compared with 99 (97, 100) for the modified group (p < 0.05). The KSS functional scores 1 year after operation in the two groups were 90 (65, 90) and 100 (90, 100) (p < 0.05). The incidences of complications due to the rotation of K-wires in the traditional group and the modified group were 76.1% (35 of 46) and 6.9% (2 of 29) with a significant statistical difference (p < 0.05).

Conclusion

This study shows that our modified tension band therapy is an effective strategy for antirotation in the treatment of patellar fracture and proves that it can achieve better clinical outcomes than the traditional K-wire tension band method. This new strategy may be a safe and effective clinical technique for the treatment of patellar fracture. However, more prospective randomized controlled trials with larger sample sizes are still needed to further prove its efficacy.

Abdominal wall heterotopic ossification following damage control laparotomy: an unusual bone to pick

BACKGROUND

Heterotopic ossification (HO) refers to the development of extra-skeletal bone in muscle and soft tissues, following tissue insult secondary to surgery or trauma. This pathological process is considered as the result of severe inflammatory cell cascade initiated after local trauma and subsequent attempt at tissue repair involving resident mesenchymal cells. We present a series of 12 cases of abdominal HO (AHO), over 8 years, following damage control laparotomies (DCLs).

METHODS

Medical records of 50 patients who underwent DCLs at Alice Springs Hospital between 2010 and 2018 were retrospectively reviewed for AHO. Demographic data were extracted. Abdominal X-rays and computed tomography scans of 47 patients were reviewed for AHO.

RESULTS

Twelve patients (25%) developed AHO of varying diversity ranging from small insignificant lesions to clinically palpable lesions in the abdominal wall. Data revealed relatively younger male preponderance. DCL for severe acute pancreatitis (SAP) was associated with AHO (P < 0.1, 90% CI). Longer periods of ventilation, intensive care unit stay and admission to hospital were strongly associated with AHO (P < 0.01, 95% CI). Occurrence of AHO with SAP was significantly higher compared to patients without SAP (relative risk 3.54, P < 0.001). Only two patients required surgical excision of HO prior to definitive closure of the abdomen.

CONCLUSION

The authors conclude that AHO occurred more frequently in younger males. DCL for SAP was a significant risk factor. Extended periods of ventilation, intensive care unit stay and hospital admission were strongly associated with the development of AHO. Preoperative detection of HO is essential prior to planning definitive closure of the abdomen.

Management of Open Abdomen After Trauma Laparotomy: A Comparative Analysis of Dynamic Fascial Traction and Negative Pressure Wound Therapy Systems

BACKGROUND

Management of the post-traumatic open abdomen (OA) using negative pressure wound therapy (NPWT) alone is associated with low rates of primary fascial closure. The abdominal reapproximation anchor (ABRA) system exerts dynamic medial fascial traction and may work synergistically with NPWT to facilitate primary fascial closure.

METHODS

Patients with an OA following trauma laparotomy between 2009 and 2018 were identified from a prospectively maintained institutional database. Patients treated with ABRA in conjunction with NPWT (ABRA) versus NPWT alone (NPWT) were compared in terms of primary fascial closure rate, number of surgeries to closure, tracheostomy duration, length of stay and incidence of entero-atmospheric fistula. Multivariable linear regression was performed to identify predictors of tracheostomy duration.

RESULTS

We identified 48 patients [ABRA, 12 and NPWT, 36]. The ABRA group was significantly younger (25 vs. 37 years, p = 0.027) and included a lower proportion of males (58% vs. 89%, p = 0.032). Groups were similar with respect to the incidence of hollow viscus injury, injury severity score and abdominal abbreviated injury score. Compared to the NPWT group, the ABRA group had a significantly higher rate of primary fascial closure (100% vs. 28%, p < 0.001), fewer surgeries to abdominal closure (2 vs. 2.5, p = 0.023) and shorter duration of tracheostomy (15.5 vs. 36 days, p = 0.008). There were no differences in length of stay or incidence of entero-atmospheric fistula. On multivariable linear regression, ABRA placement was an independent predictor of shorter tracheostomy duration, after adjusting for covariates (β = - 0.294, p = 0.036).

CONCLUSION

For the post-traumatic OA, ABRA coupled with NPWT achieves a higher rate of primary fascial closure compared to NPWT alone, while requiring fewer surgeries and a shorter duration of tracheostomy.

Regulation of heterotopic ossification by monocytes in a mouse model of aberrant wound healing

Heterotopic ossification (HO) is an aberrant regenerative process with ectopic bone induction in response to musculoskeletal trauma, in which mesenchymal stem cells (MSC) differentiate into osteochondrogenic cells instead of myocytes or tenocytes. Despite frequent cases of hospitalized musculoskeletal trauma, the inflammatory responses and cell population dynamics that regulate subsequent wound healing and tissue regeneration are still unclear. Here we examine, using a mouse model of trauma-induced HO, the local microenvironment of the initial post-injury inflammatory response. Single cell transcriptome analyses identify distinct monocyte/macrophage populations at the injury site, with their dynamic changes over time elucidated using trajectory analyses. Mechanistically, transforming growth factor beta-1 (TGFβ1)-producing monocytes/macrophages are associated with HO and aberrant chondrogenic progenitor cell differentiation, while CD47-activating peptides that reduce systemic macrophage TGFβ levels and help ameliorate HO. Our data thus implicate CD47 activation as a therapeutic approach for modulating monocyte/macrophage phenotypes, MSC differentiation and HO formation during wound healing.