Are occult fractures of the hip and pelvic ring mutually exclusive?

An Umbrella Review and Updated Meta-Analysis of Imaging Modalities in Occult Scaphoid and Hip and Femoral Fractures

Background: Occult fractures may cause multiple morbidities. If occult fractures were detected earlier, complications may be preventable. This umbrella review and updated meta-analysis will aim to evaluate the use of imaging modalities in detecting occult scaphoid and hip fractures. Methods: The protocol for this study is available in the International Prospective Register of Systematic Reviews (PROSPERO) database (CRD42024525388). The literature search started and ended on 17 March 2024. We searched seven academic databases: MEDLINE, Cochrane Library, Pubmed, Science Direct, Google Scholar, WHO International Clinical Trials Registry Platform, and The Joanna Briggs Institute (JBI) database. The meta-analysis was conducted with the STATA program using the "midas" command. Results: There are four systematic reviews evaluating occult hip and femoral fractures with 6174 patients and two reviews evaluating occult scaphoid fractures with 1355 patients. The prevalence of occult scaphoid fracture and occult hip and femoral fractures is 23.87% (95% CI 18.25-29.49) and 44.8% (95% CI 39.38-51.4), respectively. Magnetic resonance imaging (MRI) had the best posterior probability of positive likelihood ratio (LR+) with 95% and 96% and negative likelihood ratio (LR-) with 0.15% and 1% for both occult scaphoid and hip fractures, respectively, assuming a 25% baseline. MRI could both confirm and exclude occult hip fractures while it can only confirm occult scaphoid fractures. Bone scans are inappropriate for either type of occult fractures The level of evidence for occult scaphoid fracture is weak while it is suggestive for occult hip fractures. Conclusion: The findings strengthen the use of MRI after an initially negative radiograph fracture for occult hip and femoral fractures, with a CT scan as a viable second option.

Standard imaging in the emergency department in geriatric patients with immobilizing pelvic pain after low-energy trauma or without trauma: X-ray vs. computed tomography

PURPOSE

Geriatric pelvic ring injuries, evaluated solely by X-ray, are often misclassified or even missed. This can result in prolonged immobilization and persistent pelvic pain. The aim of this study was to assess the sensitivity and specificity of X-ray imaging in patients aged ≥ 70 years with immobilizing pelvic pain.

METHODS

107 geriatric patients (23 males, 84 females) with immobilizing pain after traumatic or atraumatic causes were included in this retrospective study. 91 patients had an anteroposterior (AP) X-ray of the pelvis and after that a computed tomography (CT) of the pelvis. All patients were treated in a level 1 trauma center from December 2018 to September 2020. The mean age was 83.07 ± 6.08 years.

RESULTS

The overall evaluation of the diagnostic performance of AP Pelvic X-ray imaging in the study population compared to the CT pelvis ("gold standard") resulted in a sensitivity of (2.7 %) and a specificity of (94.4 %). Specific for pelvic ring fractures in the study population there was a sensitivity of (3.4 %) and a specificity of (94.4 %).

CONCLUSION

The results highlights issues with the AP Pelvic X-ray as the diagnostic tool of choice in this study population, confirming the findings of previous studies on the underestimated problem of osteoporotic pelvic ring fractures in geriatric patients. This again confirms the need for a new optimized diagnostic algorithm, which takes into account the differences of the orthogeriatric patient cohort.

The Necessity of CT Hip Scans in the Investigation of Occult Hip Fractures and Their Effect on Patient Management

The diagnostic challenge of negative plain radiography in the context of a previously ambulatory patient is increasing with the rise in geriatric trauma. These patients are often diagnosed with small undisplaced fractures of the pelvis and femur which may not alter management. This study aims to assess the frequency at which computed tomography (CT) hip scans altered patient management and whether two X-ray projections of the hip affected fracture detection rate. All CT hip scans performed over a three-year period were identified retrospectively. Only CT hips pertaining to the identification of occult fractures were included in the study. A total of 447 (63.6%) CT hips were performed to exclude an occult fracture, which was only detected in 108 (24.1%) of the scans requested. The majority were subcapital (n = 58, 53.7%) or intertrochanteric (n = 39, 36.1%). There was no significant difference between fracture detection rates when comparing one and two views of the pelvis. 82.4% (n = 89) of occult hip fractures were managed operatively. CT imaging led to a change in patient management in 20% of cases. The frequency at which CT scan detects and alters management in occult hip fractures confirms the justification for its use. Increasing the number of X-ray projection views does not decrease the reliance on CT. Pelvic ring fractures are common in nonambulatory patients following trauma, and if confirmed on initial imaging, subsequent imaging to exclude a concurrent occult hip is unnecessary. The focus of further research should be towards the development of investigation algorithms which decrease the reliance on CT and defining the optimal surgical criteria for occult hip fractures.

Use of Advanced Imaging for Radiographically Occult Hip Fracture in Elderly Patients: A Systematic Review and Meta-Analysis

Background The overall rate of hip fractures not identified on radiographs but that require surgery (ie, surgical hip fractures) remains unclear in elderly patients who are suspected to have such fractures based on clinical findings. Moreover, the importance of advanced imaging in these patients has not been comprehensively assessed. Purpose To estimate the frequency of radiographically occult hip fracture in elderly patients, to define the higher-risk subpopulation, and to determine the diagnostic performance of CT and bone scanning in the detection of occult fractures by using MRI as the reference standard. Materials and Methods A literature search was performed to identify English-language observational studies published from inception to September 27, 2018. Studies were included if patients were clinically suspected to have hip fracture but there was no radiographic evidence of surgical hip fracture (including absence of any definite fracture or only presence of isolated greater trochanter [GT] fracture). The rate of surgical hip fracture was reported in each study in which MRI was used as the reference standard. The pooled rate of occult fracture, diagnostic performance of CT and bone scanning, and strength of evidence (SOE) were assessed. Results Thirty-five studies were identified (2992 patients; mean age, 76.8 years ± 6.0 [standard deviation]; 66% female). The frequency of radiographically occult surgical hip fracture was 39% (1110 of 2835 patients; 95% confidence interval [CI]: 35%, 43%) in studies of patients with no definite radiographic fracture and 92% (134 of 157 patients; 95% CI: 83%, 98%) in studies of patients with radiographic evidence of isolated GT fracture (moderate SOE). The frequency of occult fracture was higher in patients aged at least 80 years (44%, 529 of 1184), those with an equivocal radiographic report (58%, 71 of 126), and those with a history of trauma (41%, 977 of 2370) (moderate SOE). CT and bone scanning yielded comparable diagnostic performance in the detection of radiographically occult hip fracture (P = .67), with a sensitivity of 79% and 87%, respectively (low SOE). Conclusion Elderly patients with acute hip pain and negative or equivocal findings at initial radiography have a high frequency of occult hip fractures. Therefore, the performance of advanced imaging (preferably MRI) may be clinically appropriate in all such patients. © RSNA, 2020 Online supplemental material is available for this article.

The diagnostic and management challenge for concomitant fragility fractures of pelvis and hip - a Case series with literature review

BACKGROUND

Fragility fractures of hip and pelvis in the elderly population are common. They do co-exist but are frequently missed and undertreated.

METHODS AND RESULTS

3 cases of concomitant fragility fractures of hip and pelvis were identified. Hip fractures were treated with cemented hemiarthroplasty or cephalomedullary nail fixation, while pelvic fractures were treated with percutaneous screw fixation in same general anesthesia session. Anti-osteoporotic treatments were offered. Subjects were followed up for 1 year.

CONCLUSION

Surgical treatment of fragility hip and pelvic fractures improves fracture stability, achieves better pain relief and allows earlier mobilization. Anti-osteoporotic treatment is essential as secondary prevention in fragility fractures.

Magnetic resonance imaging for verifying hip fracture diagnosis why, when and how?

INTRODUCTION

Hip fractures are commonly diagnosed by plain radiography. When a patient presents with negative radiographs and high clinical suspicion of fracture, guidelines recommend proceeding with magnetic resonance imaging (MRI) to diagnose the patient. The aim of this study was to assess the use of MRI in diagnosing hip fractures following trauma to the hip and describe clinical outcome after MRI-diagnosed hip fractures. The perspective was to develop new recommendations for MRI use.

MATERIALS AND METHODS

616 patients at a university hospital fulfilled the inclusion criteria of having an MRI scan of the hip following trauma between the years of 2005 and 2014. Data was collected from the patients' medical records.

RESULTS

The annual number of MRIs increased over the ten-year period. Out of 616 MRI scans 228 (37%) showed fracture of the hip with a dominance of trochanteric fractures, 185 (30%) revealed pelvic fracture and 183 (29%) were negative. No patient with acute pelvic fracture had associated fracture of the hip. The main reason to proceed with MRI was a strong clinical suspicion of fracture in patients with negative initial radiographs. Amongst the 228 patients with fracture, 187 (82%) were treated operatively. Of patients with hip fracture, 90 (39%) patients suffered a general complication and 11 (5%) had hip complications. The complication rate of patients with fracture on MRI was compared to that of a cohort of general hip fracture patients at our hospital. No significant difference in twelve months' survival or general complications could be found, but the MRI group had a significantly lower hip complication rate.

CONCLUSION

The diagnosis set by MRI, with high share of pelvic fractures or no fracture, reflects the difficulty in differential diagnosing this group of patients. The rate of occult hip fractures was low and patients with pelvic fractures already known from X-ray did not have additional hip fractures. We found an increase in the annual number of MRIs during the 10-year-period. MRI-diagnosed hip fracture patients do not suffer more complications than the regular hip fracture patient.

Occult fractures of the proximal femur: imaging diagnosis and management of 82 cases in a regional trauma center

BACKGROUND

Occult hip fractures are often difficult to identify in busy trauma units. We aimed to present our institutions experience in the diagnosis and treatment of occult fractures around the hip and to help define a clinical and radiological management algorithm.

METHOD

We conducted a seven-year retrospective hospital medical record analysis. The electronic database was searched for ICD-10 CM codes S72.0 and S72.1 used for proximal femoral fractures upon patient discharge. We identified 34 (4.83 %) femoral neck fractures and 48 (4.42 %) trochanteric fractures labeled as occult.

RESULTS

The majority of the cases were diagnosed by primary MRI scan (57.4 %) and 12 were diagnosed by emergency CT scan (14.6 %). For the remaining cases the final diagnosis was confirmed by 72 h CT scan in 9 patients (representing 39 % of the false negative cases) or by MRI in the rest of 14 patients. MRI was best at detecting incomplete pertrochanteric fracture patterns (13.45 % of total) and incomplete fractures of the greater trochanter (3.65 % of total) respectively. It also detected the majority of Garden I femoral neck fractures (20.7 % of total). CT scanning accurately detected 100 % of Garden 2 fractures (2.44 %) and 25 % (3.65 %) of the complete pertrochanteric fractures (false negative 25 %).

CONCLUSION

Occult fractures should be suspected in all patients with traumatic onset of hip pain that is inconsistent with normal radiographic findings. MRI is the golden standard but not as readily available not as cheap and not quite as quick to perform as as a CT scan. The latter which in turn can provide falsely negative results in the first 24 h. Improved imaging protocols could expedite management and improve treatment.

Radiographically occult femoral and pelvic fractures are not mutually exclusive: a review of fractures detected by MRI following low-energy trauma

OBJECTIVES

The purpose of this study was to review the MRI examinations of a large group of low-energy trauma patients in whom pelvic MRI had detected radiographically occult fractures, in order to characterize prevailing fracture patterns and determine how often co-existing proximal femoral and pelvic fractures were observed.

METHODS

All patients having pelvic MRI over 5 years were identified. Word-search software selected 269 MRI reports containing the term ‘fracture’. Further scrutiny identified 168 with diagnosis of fracture. MRI request and imaging record review identified 102 low-energy trauma cases that had MRI for clinical suspicion of fracture despite normal radiographs. Sixty-six cases were excluded for the following reasons: no expressed clinical suspicion of occult fracture; history suggesting high-energy trauma;skeletal co-morbidity hindering acute fracture identification;interval more than 2 weeks between radiographs and MRI. The 102 study MRI examinations, which employed a limited two-sequence protocol, were reviewed. Any fracture that had not been appreciated on radiographs was recorded and characterized as femoral, pelvic, or co-existing femoral and pelvic fractures.

RESULTS

The 102 study cases had a median age of 82 years.The median interval between pelvic radiographs and MRI was 3 days. MRI showed undiagnosed femoral fracture in 48/102 cases (47.1%), sacral fracture in 41/102 (40.2%),and pubic fracture in 55/102 (53.9%). In 11/102 cases(10.8%), MRI showed undiagnosed fractures of both proximal femur and pelvic ring (seven sacral, six pubic bone, two other site fractures). In 10/11 cases with coexisting femoral and pelvic fractures, the femoral fracture was incomplete.

CONCLUSIONS

Limited pelvic MRI found a high prevalence of radiographically occult femoral and pelvic fractures in low-energy trauma patients, with clinical suspicion of fracture despite normal radiographs. Co-existing occult femoral and pelvic ring fractures were commonly observed, and in such cases, the femoral fracture was likely to be incomplete and multiple pelvic fractures were typically present.

Occult hip and pelvic fractures and accompanying muscle injuries around the hip

METHOD

We investigated the incidence of occult hip and pelvic fractures and associated muscle injuries around the hip.

PATIENTS

A total of 113 patients aged 60-102 years with suspected hip fracture but negative plain radiographs underwent further examination by magnetic resonance imaging (MRI) within 2 days after an X-ray examination. Coronal and axial T1 and T2 or short tau inversion recovery sequences of MRI of the hip including the sacrum were obtained.

RESULTS

One hundred and two cases (90.2%) had bone or soft-tissue abnormalities and 83 cases (73.5%) had fractures of the hip and/or pelvis. The frequency of hip fracture and pelvic fracture was almost the same. More than half of the patients among those with pelvic fractures sustained occult sacral fractures; therefore, it was important to determine if a sacral fracture was involved when occult hip fracture was suspected. Muscles located at the lateral aspect of the hip, such as gluteus maximus, gluteus medius, gluteus minimus and quadratus femoris, were frequently injured in cases with intertrochanteric and greater trochanter fracture, suggesting that direct impact may be associated with fractures of the trochanteric region. However, hip rotator and adductor muscles such as obturator internus, obturator externus and adductor brevis were commonly injured in cases with pelvic fracture, indicating indirect force mediated by these muscles may be associated with pelvic fracture.

CONCLUSION

Occult hip and pelvic fractures were almost equally seen among 113 cases with suspected hip fracture but were negative on plain radiography. Different patterns of associated muscle injuries in cases of occult hip fracture and pelvic fracture suggest that the mechanism of hip fracture and pelvic fracture is possibly different.

Fractured neck of femur--internal fixation versus arthroplasty

BACKGROUND

Surgery is the treatment of choice for fractured neck of femur. For middle-aged patients (aged ca. 40 to 65), there is considerable debate over the indications for arthroplasty or internal fixation. The choice of surgical technique varies widely from one region to another. In this article, we discuss the main criteria that should be used in making this decision.

METHODS

We selectively reviewed the literature on the diagnosis and treatment of fractured neck of femur, including the current guideline of the German Society for Trauma Surgery (Deutsche Gesellschaft für Unfallchirurgie, DGU) and recent findings from the field of health services research.

RESULTS

The treatment of middle-aged patients with dislocated fractures should be based on rational decision-making. The patient's level of activity before the accident should be judged in terms of his or her previous mobility, independence in daily activities, and mental status. Internal fixation is recommended if the fracture can be adequately repositioned, the bone is of good quality, and there is no evidence of osteoarthritis. Fractures that are more than 24 hours old should be treated with total hip arthroplasty. Hemiprostheses are appropriate for very old patients. Physically frail, bedridden, and/or demented patients should undergo internal fixation of the fracture. For non-displaced or impacted fractures, functional treatment (i.e., prophylactic securing of the fracture with screws or nails) is indicated. Rapid diagnosis and a short time in bed before surgery lower the rate of complications. Internal fixation with preservation of the femoral head should ideally be performed within the first 6 hours of trauma, and within the first 24 hours at most.

CONCLUSION

Despite the increasing scarcity of resources, treatment should still be based on well-founded clinical guidelines. Minimally invasive surgery enables better function in the early postoperative phase and can thereby lower complication rates. An interdisciplinary concept for the postoperative care of elderly patients also has a major effect on the outcome.

The use of MRI to detect occult fractures of the proximal femur: a study of 102 consecutive cases over a ten-year period

An MR scan was performed on all patients who presented to our hospital with a clinical diagnosis of a fracture of the proximal femur, but who had no abnormality on plain radiographs. This was a prospective study of 102 consecutive patients over a ten-year period. There were 98 patients who fulfilled our inclusion criteria, of whom 75 were scanned within 48 hours of admission, with an overall mean time between admission and scanning of 2.4 days (0 to 10). A total of 81 patients (83%) had abnormalities detected on MRI; 23 (23%) required operative management. The use of MRI led to the early diagnosis and treatment of occult hip pathology. We recommend that incomplete intertrochanteric fractures are managed non-operatively with protected weight-bearing. The study illustrates the high incidence of fractures which are not apparent on plain radiographs, and shows that MRI is useful when diagnosing other pathology such as malignancy, which may not be apparent on plain films.