Factors Affecting the Second Complete Atypical Femoral Fracture after the First Atypical Fracture.

OBJECTIVES: Atypical femoral fracture (AFF) is an atypical low-energy subtrochanteric and diaphyseal femoral fracture. Even if bone fusion is achieved in patients with AFF, the risk of AFF in the contralateral femur must be considered. This study aimed to investigate the factors affecting complete AFF in the contralateral femur and conservatively treated incomplete AFF. SUBJECT AND METHODS: Radiographs of 111 femurs in 104 AFF cases were examined, and the femurs were classified as follows: 85 contralateral femurs with complete AFF; 18 contralateral femurs with incomplete AFF; 8 femurs with incomplete AFF without surgical treatment. Various patients' clinical data were collected, and we investigated the factors affecting the second complete AFF. RESULTS: Complete fractures occurred in 10 (9.7%) of 103 femurs without incomplete AFF at the first visit and in 3 (37.5%) of 8 femurs with incomplete AFF. The Kaplan-Meier curve revealed that lateral cortical bone thickening and thigh pain were associated with significantly poorer prognoses (p = 0.026 and p = 0.013, respectively). Multivariate analyses revealed that eldecalcitol usage after AFF onset (p = 0.0094) and previous use of bisphosphonate or denosumab (p = 0.0126) were protective factors for second complete AFF and that the presence of thigh pain (p = 0.0134) was a risk factor for second complete AFF. CONCLUSIONS: Eldecalcitol administration after bone union of first AFF may prevent AFF recurrence. In addition, painful incomplete AFF has a high risk of developing a complete fracture.

Evaluation of the Nature and Etiologies of Risk Factors for Diaphyseal Atypical Femoral Fractures.

OBJECTIVES: Differences in mechanisms of subtrochanteric and diaphyseal atypical femoral fractures (AFFs) are speculated in studies that analyzed differences in the patients' background. However, the etiologies of each type of AFF have not been studied in detail. This study aimed to investigate the nature and etiologies of the risk factors for diaphyseal AFFs. MATERIALS AND METHODS: Eighty consecutive Japanese patients with 91 diaphyseal AFFs (AFF group) and 110 age-matched women with osteoporosis (non-AFF control group) were included. Their clinical data were compared; factors affecting AFFs were investigated, and the etiologies of the risk factors for diaphyseal AFFs were examined. RESULTS: Multivariate analysis revealed that femoral serrated changes, bisphosphonate or denosumab usage, and lateral and anterior femoral curvatures were risk factors for diaphyseal AFFs (p < 0.0011, p = 0.0137, and p < 0.0001, respectively). Multivariate analyses revealed that serrated changes and low serum 25(OH)D levels affected the lateral curvature (p = 0.0088 and 0.0205, respectively), while serrated changes affected the anterior curvature (p = 0.0006), each significantly affected the femoral curvature. High serum calcium (Ca) levels, lateral femoral curvature, and anterior femoral curvature were predictors of serrated changes (p = 0.0146, 0.0002, and 0.0098, respectively). CONCLUSION: Risk factors for diaphyseal AFFs were bone resorption inhibitor usage, a strong femoral curvature, and serrated changes. Low serum 25(OH)D levels and serrated changes are risk factors for lateral curvature, while a high serum Ca level is a risk factor for serrated changes.

Evaluation of factors affecting the occurrence of second atypical fracture after bone union of the first atypical fracture.

PURPOSE: Teriparatide is sometimes used in the treatment of atypical femoral fracture (AFF). Even if bone union is achieved, orthopedic physicians must consider the risk of relapse. This study aimed to investigate the factors affecting AFF recurrence, and to determine the appropriate treatment for osteoporosis after bone union. METHODS: One hundred thirty-one consecutive AFFs in 113 Japanese patients were included. Eleven patients had AFF in the unaffected limb (9 patients) after the first AFF or re-fracture at the original fracture site (2 patients) after bone union of the first AFF was confirmed. We divided all patients into two groups: the second fracture group (22 AFFs in 11 patients) and non-second fracture group (109 AFFs in 102 patients). We compared clinical information between the 2 groups and investigated the factors affecting AFF recurrence using the Student t-, Welch t-, and chi-square tests. RESULTS: Although there was no significant difference in clinical characteristics between the 2 groups, multivariate analysis of factors associated with AFF recurrence identified short duration of treatment with teriparatide and active vitamin D3 (p = 0.0408 and 0.0366, respectively) as risk factors. Even in the analysis excluding subtrochanteric AFF, short periods of teriparatide and active vitamin D3 administration were observed as risk factors (p = 0.0484 and 0.0346, respectively). CONCLUSION: The administration of teriparatide for as long as possible after occurrence first AFF and the use of active vitamin D3 after completion of teriparatide therapy may be the most effective strategy to prevent the recurrence of AFF.

High prevalence of abdominal aortic aneurysm in patients with chronic low back pain.

Low back pain (LBP) is one of the most common symptoms in outpatient clinics, and abdominal aortic aneurysm (AAA) is one of the causes of LBP. In the present study, we examined the prevalence of chronic LBP in patients with aortic aneurysm. The study included 23 patients with AAA and 23 patients with thoracic aortic aneurysm (TAA); all of them visited a regional center hospital in Akita, Japan. A total of 207 hypertension patients were also enrolled as a control. Chronic LBP was defined in patients who visited the orthopedic outpatient clinic for the LBP treatment for more than three months. The prevalence of chronic LBP in the AAA group (52.2%) was significantly higher than that in the TAA (17.4%, P < 0.05) or hypertension patients (11.6%, P < 0.01). The rate of a trigger point (TP) injection was significantly higher in the AAA group or the TAA group than that in hypertension patients (P < 0.01, P < 0.05), but there was no significant difference between the AAA and TAA groups. The TP injection represents an injection of local anesthesia to the low back muscles. We also evaluated the involvement of various factors in LBP caused by AAA, such as age, gender, blood pressure, the existence of dissection, and the maximum diameter of AAA, but none of them showed significant relationship to LBP. The prevalence of LBP is high in AAA patients, and doctors who treat chronic LBP should be aware of AAA as a potential cause of LBP.

Trigger finger appearing as gradually increasing digital nerve disorder after surgical treatment.

Trigger finger is a common disease, and operative treatments are often applied for it. Digital nerve injury is one of the complications of this surgical treatment, and paresthesia and sensory disturbance occur early after the operation. This paper presents a case of trigger finger appearing gradually as increasing digital nerve disorder after surgical treatment. In the second surgery, scar tissue covered the palmar MP joint where the A1 pulley had existed before, and palmar digital neurovascular tissue of the ulnar side was found on the inside of the scar. The ulnar digital nerve showed swelling like a neuroma, and bilateral digital nerves existed nearer to the center of the flexor pollicis longus tendon than normal digital nerves. Even when we operate on trigger finger by open release, we should create an appropriate surgical space for observation and be careful of digital nerve injury.