Incidence and severity of femoral head avascularity after femoral neck or intertrochanteric fractures on preoperative bone single photon emission computed tomography/computed tomography: preliminary study

Methods to predict osteonecrosis of femoral head after femoral neck fracture: a systematic review of the literature

BACKGROUND

Femoral neck fracture (FNF) is a very common traumatic disorder and a major cause of blood supply disruption to the femoral head, which may lead to a severe long-term complication, osteonecrosis of femoral head (ONFH). Early prediction and evaluation of ONFH after FNF could facilitate early treatment and may prevent or reverse the development of ONFH. In this review paper, we will review all the prediction methods reported in the previous literature.

METHODS

Studies on the prediction of ONFH after FNF were included in PubMed and MEDLINE databases with articles published before October 2022. Further screening criteria were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. This study highlights all the advantages and disadvantages of the prediction methods.

RESULTS

There were a total of 36 studies included, involving 11 methods to predict ONFH after FNF. Among radiographic imaging, superselective angiography could directly visualize the blood supply of the femoral head, but it is an invasive examination. As noninvasive detection methods, dynamic enhanced magnetic resonance imaging (MRI) and SPECT/CT are easy to operate, have a high sensitivity, and increase specificity. Though still at the early stage of development in clinical studies, micro-CT is a method of highly accurate quantification that can visualize femoral head intraosseous arteries. The prediction model relates to artificial intelligence and is easy to operate, but there is no consensus on the risk factors of ONFH. For the intraoperative methods, most of them are single studies and lack clinical evidence.

CONCLUSION

After reviewing all the prediction methods, we recommend using dynamic enhanced MRI or single photon emission computed tomography/computed tomography in combination with the intraoperative observation of bleeding from the holes of proximal cannulated screws to predict ONFH after FNF. Moreover, micro-CT is a promising imaging technique in clinical practice.

Usefulness of Bone SPECT/CT for Predicting Avascular Necrosis of the Femoral Head in Children with Slipped Capital Femoral Epiphysis or Femoral Neck Fracture

OBJECTIVE

This study aimed to investigate the usefulness of bone single-positron emission tomography/computed tomography (SPECT/CT) of the hip in predicting the later occurrence of avascular necrosis (AVN) after slipped capital femoral epiphysis (SCFE) or femoral neck fracture in pediatric patients. The quantitative parameters of SPECT/CT useful in predicting AVN were identified.

MATERIALS AND METHODS

Twenty-one (male:female, 10:11) consecutive patients aged < 18 years (mean age ± standard deviation [SD], 11.0 ± 2.7 years) who underwent surgery for SCFE or femoral neck fracture and postoperative bone SPECT/CT were included. The maximum standardized uptake value (SUV), mean SUV, and minimum SUV of the femoral head were measured. The ratios of the maximum SUV, mean SUV, and minimum SUV of the affected femoral head to the contralateral side were determined. Patients were followed up for > 1 year after the surgery. The SPECT/CT parameters were compared between patients who developed AVN and those who did not. The accuracy of SPECT/CT parameters for predicting AVN was assessed.

RESULTS

Six patients developed AVN. There was a significant difference in the ratio of the mean SUV among patients who developed AVN (mean ± SD, 0.8 ± 0.3) and those who did not (1.1 ± 0.2, p = 0.018). However, there were no significant differences in the ratios of the maximum and minimum SUV between the groups (all p = 0.205). For the maximum, mean, and minimum SUVs, no significant differences were observed between the groups (p = 0.519, 0.733, and 0.470, respectively). The cutoff mean SUV ratio of 0.87 yielded a 66.7% sensitivity and 93.2% specificity for predicting AVN.

CONCLUSION

Quantitative bone SPECT/CT is useful for evaluating femoral head viability in pediatric patients with SCFE or femoral neck fractures. Clinicians should consider the high possibility of later AVN development in patients with a decreased mean SUV ratio.

Hypoxia in Bone and Oxygen Releasing Biomaterials in Fracture Treatments Using Mesenchymal Stem Cell Therapy: A Review

Bone fractures have a high degree of severity. This is usually a result of the physical trauma of diseases that affect bone tissues, such as osteoporosis. Due to its highly vascular nature, the bone is in a constant state of remodeling. Although those of younger ages possess bones with high regenerative potential, the impact of a disrupted vasculature can severely affect the recovery process and cause osteonecrosis. This is commonly seen in the neck of femur, scaphoid, and talus bone. In recent years, mesenchymal stem cell (MSC) therapy has been used to aid in the regeneration of afflicted bone. However, the cut-off in blood supply due to bone fractures can lead to hypoxia-induced changes in engrafted MSCs. Researchers have designed several oxygen-generating biomaterials and yielded varying degrees of success in enhancing tissue salvage and preserving cellular metabolism under ischemia. These can be utilized to further improve stem cell therapy for bone repair. In this review, we touch on the pathophysiology of these bone fractures and review the application of oxygen-generating biomaterials to further enhance MSC-mediated repair of fractures in the three aforementioned parts of the bone.

Efficacy and complications after delayed fixation of femoral neck fractures in children

OBJECTIVE

This study evaluated the efficacy of surgery for femoral neck fractures in children after a 24-h delay and the factors affecting the risk of complications.

METHODS

The study included 16 children who underwent surgery after the first 24 h for femoral neck fractures. According to Delbet's classification, there were 2 type I, 11 type II, and 3 (four hips) type III cases. The mean time from injury to surgery was 85 h (range 27-240 h). According to Garden's classification, there were 1 type II, 14 type III, and 1 type IV (two hips) cases. Initial surgery consisted of closed reduction and hematocele drainage with a 20-mL needle tube. If the procedure failed, open reduction was performed. Internal fixation (K-wire pinning, screw) was performed after closed (n = 9) or open (n = 8) reduction. The results were assessed using the Ratliff criteria after a mean follow-up of 23.2 months. Patient age, type of fracture, complications, treatment, and avascular necrosis (AVN) were evaluated.

RESULTS

The results were good in 15 hips (88.2%) and fair in 2 hips (11.8%, one type II case with closed reduction and one type I case with open reduction). The most frequent complication was AVN (4 of 17; 23.5%; three Ratliff good and one fair), which was significantly related to poor outcomes. AVN occurred in one hip in the closed reduction group (Delbet's type II, 12.5%) and in three in the open reduction group (one Delbet's type I, 50%; two Delbet's type II, 66.7%). There were no significant differences in the time from injury to operation (27, 54, 64, and 116 h) and AVN incidence or Ratliff criteria.

CONCLUSIONS

The efficacy of delayed reduction fixation of the femoral neck was better in the closed reduction group than in the open reduction group. Fracture location closer to the femoral head and older age affected the incidence of AVN.

Computed Tomography (CT) Protocols Associated with Cardiac and Bone Single-Photon Emission Computed Tomography/CT (SPECT/CT) in Korea

PURPOSE

Single-photon emission computed tomography/computed tomography (SPECT/CT) is an advanced hybrid nuclear medicine technology that generates both functional and anatomical images in a single study. As utilization of SPECT/CT in Korea has been increasing, the purpose of this study was to survey its application of cardiac and skeletal SPECT/CT imaging for protocol optimization.

METHODS

We surveyed CT protocols established for cardiac and skeletal SPECT/CT. We searched the guidelines for the CT protocols for SPECT/CT and reviewed the literature recently published.

RESULTS

Among 36 hybrid SPECT scanners equipped with four or more multi-channel detector CTs (MDCTs), 18 scanners were used to perform cardiac studies at both very low current CT (30-80 mA; 11.1%) and ultra-low current CT (13-30 mA; 88.9%). Among the 33 canners, very low current (≤ 80 mA) CT or low current CT (80-130 mA) was used in 23.5%, and 41.8% for spine disorders, and in 36.4% or 30.3% for foot/ankle disorders, respectively. In the CT reconstructions, slice thickness of 5 mm for cardiac studies was most commonly used (94.4%); thinner slices (0.6-1.0 mm) for spine and foot/ankle studies were used in 24.2% and 45.5%, respectively. We also reviewed the international guidelines.

CONCLUSIONS

The results and current recommendations will be helpful for optimizing CT protocols for SPECT/CT. Optimization of SPECT/CT protocols will be required for generating the proper strategy for the specific lesions and clinical purpose.

The efficacy of Enhanced Recovery after Surgery (ERAS) for elderly patients with intertrochanteric fractures who received surgery: study protocol for a randomized, blinded, controlled trial

Background

Intertrochanteric fracture (ITF) is increasing with the rapid increase in the aging population, often causes a high mortality rate in old patients and increases the economic burden of the family and society. ERAS (Enhanced Recovery after Surgery) is a powerful guarantee for patients to accelerate their recovery after surgery. TCM (traditional Chinese medicine) promotes repair of injured tissues and eliminates traumatic aseptic inflammation. Therefore, this prospective randomized controlled clinical trial aims to evaluate the clinical effect of the evidence-based ERAS pathway of integrating TCM with western medicine on perioperative outcomes in ITF patients undergoing intramedullary fixation and provide reliable evidence-based data for applying the program to clinical practice.

Methods/design

We will conduct a prospective randomized, blinded, controlled trial to compare the effectiveness of ERAS care pathway with traditional care pathway and to investigate whether the ERAS care pathway can improve the perioperative outcome in ITF patients undergoing intramedullary fixation. A total of 60 patients with ITF will be enrolled and treated with the two care pathway, respectively. Length of stay, economic indicators, Harris score, VAS score, time to get out of bed, 30-day readmission rates, postoperative transfusion rates, discharge to home, and mortality will be evaluated. Any signs of acute adverse reactions will be recorded at each visit during treatment.

Discussion

Although an evidence-based process using the best available literature and Delphi expert-opinion method has been used to establish an ERAS pathway of integrating TCM with western medicine, there is a lack of consensus about its effectiveness. This trial will provide convincing evidence about the effect of ERAS pathway.

Trial registration

Registered on 12 October 2019. Trial number is ChiCTR1900026487.