What Factors Are Associated With Implant Breakage and Revision After Intramedullary Nailing for Femoral Metastases?

Reoperation after surgery for bone metastasis of renal cell carcinoma

BACKGROUND AND OBJECTIVE

The prognosis of metastatic renal cell carcinoma (RCC) has markedly improved with the advent of molecular targeted therapies and immune checkpoint inhibitors. However, the therapeutic response in patients with bone metastasis remains low; therefore, surgery still plays a significant role in treatment of bone metastasis. It is important to maintain quality of life for patients with bone metastasis from RCC and avoid reoperation after surgery for bone metastasis. Therefore, we investigated the risk factors for reoperation after surgery in patients with bone metastasis from RCC.

METHODS

We retrospectively studied 103 bones of 97 patients who underwent surgery for bone metastasis of RCC from 2001 to 2023 at our institutions.

RESULTS

Reoperation was performed in 10 (9.7%) of 103 bones. There was no correlation between reoperation-free survival and any of the following variables: preoperative and postoperative radiotherapy, site of bone metastasis, indication for surgery (solitary bone metastasis or impending or pathologic fractures), surgical method (intramedullary nailing fixation, curettage, or en bloc resection), preoperative embolization, or survival.

CONCLUSION

The risk of reoperation for bone metastasis of RCC does not appear to be based on the surgical method.

Does the Presence of Missing Data Affect the Performance of the SORG Machine-learning Algorithm for Patients With Spinal Metastasis? Development of an Internet Application Algorithm

BACKGROUND

The Skeletal Oncology Research Group machine-learning algorithm (SORG-MLA) was developed to predict the survival of patients with spinal metastasis. The algorithm was successfully tested in five international institutions using 1101 patients from different continents. The incorporation of 18 prognostic factors strengthens its predictive ability but limits its clinical utility because some prognostic factors might not be clinically available when a clinician wishes to make a prediction.

QUESTIONS/PURPOSES

We performed this study to (1) evaluate the SORG-MLA's performance with data and (2) develop an internet-based application to impute the missing data.

METHODS

A total of 2768 patients were included in this study. The data of 617 patients who were treated surgically were intentionally erased, and the data of the other 2151 patients who were treated with radiotherapy and medical treatment were used to impute the artificially missing data. Compared with those who were treated nonsurgically, patients undergoing surgery were younger (median 59 years [IQR 51 to 67 years] versus median 62 years [IQR 53 to 71 years]) and had a higher proportion of patients with at least three spinal metastatic levels (77% [474 of 617] versus 72% [1547 of 2151]), more neurologic deficit (normal American Spinal Injury Association [E] 68% [301 of 443] versus 79% [1227 of 1561]), higher BMI (23 kg/m 2 [IQR 20 to 25 kg/m 2 ] versus 22 kg/m 2 [IQR 20 to 25 kg/m 2 ]), higher platelet count (240 × 10 3 /µL [IQR 173 to 327 × 10 3 /µL] versus 227 × 10 3 /µL [IQR 165 to 302 × 10 3 /µL], higher lymphocyte count (15 × 10 3 /µL [IQR 9 to 21× 10 3 /µL] versus 14 × 10 3 /µL [IQR 8 to 21 × 10 3 /µL]), lower serum creatinine level (0.7 mg/dL [IQR 0.6 to 0.9 mg/dL] versus 0.8 mg/dL [IQR 0.6 to 1.0 mg/dL]), less previous systemic therapy (19% [115 of 617] versus 24% [526 of 2151]), fewer Charlson comorbidities other than cancer (28% [170 of 617] versus 36% [770 of 2151]), and longer median survival. The two patient groups did not differ in other regards. These findings aligned with our institutional philosophy of selecting patients for surgical intervention based on their level of favorable prognostic factors such as BMI or lymphocyte counts and lower levels of unfavorable prognostic factors such as white blood cell counts or serum creatinine level, as well as the degree of spinal instability and severity of neurologic deficits. This approach aims to identify patients with better survival outcomes and prioritize their surgical intervention accordingly. Seven factors (serum albumin and alkaline phosphatase levels, international normalized ratio, lymphocyte and neutrophil counts, and the presence of visceral or brain metastases) were considered possible missing items based on five previous validation studies and clinical experience. Artificially missing data were imputed using the missForest imputation technique, which was previously applied and successfully tested to fit the SORG-MLA in validation studies. Discrimination, calibration, overall performance, and decision curve analysis were applied to evaluate the SORG-MLA's performance. The discrimination ability was measured with an area under the receiver operating characteristic curve. It ranges from 0.5 to 1.0, with 0.5 indicating the worst discrimination and 1.0 indicating perfect discrimination. An area under the curve of 0.7 is considered clinically acceptable discrimination. Calibration refers to the agreement between the predicted outcomes and actual outcomes. An ideal calibration model will yield predicted survival rates that are congruent with the observed survival rates. The Brier score measures the squared difference between the actual outcome and predicted probability, which captures calibration and discrimination ability simultaneously. A Brier score of 0 indicates perfect prediction, whereas a Brier score of 1 indicates the poorest prediction. A decision curve analysis was performed for the 6-week, 90-day, and 1-year prediction models to evaluate their net benefit across different threshold probabilities. Using the results from our analysis, we developed an internet-based application that facilitates real-time data imputation for clinical decision-making at the point of care. This tool allows healthcare professionals to efficiently and effectively address missing data, ensuring that patient care remains optimal at all times.

RESULTS

Generally, the SORG-MLA demonstrated good discriminatory ability, with areas under the curve greater than 0.7 in most cases, and good overall performance, with up to 25% improvement in Brier scores in the presence of one to three missing items. The only exceptions were albumin level and lymphocyte count, because the SORG-MLA's performance was reduced when these two items were missing, indicating that the SORG-MLA might be unreliable without these values. The model tended to underestimate the patient survival rate. As the number of missing items increased, the model's discriminatory ability was progressively impaired, and a marked underestimation of patient survival rates was observed. Specifically, when three items were missing, the number of actual survivors was up to 1.3 times greater than the number of expected survivors, while only 10% discrepancy was observed when only one item was missing. When either two or three items were omitted, the decision curves exhibited substantial overlap, indicating a lack of consistent disparities in performance. This finding suggests that the SORG-MLA consistently generates accurate predictions, regardless of the two or three items that are omitted. We developed an internet application ( https://sorg-spine-mets-missing-data-imputation.azurewebsites.net/ ) that allows the use of SORG-MLA with up to three missing items.

CONCLUSION

The SORG-MLA generally performed well in the presence of one to three missing items, except for serum albumin level and lymphocyte count (which are essential for adequate predictions, even using our modified version of the SORG-MLA). We recommend that future studies should develop prediction models that allow for their use when there are missing data, or provide a means to impute those missing data, because some data are not available at the time a clinical decision must be made.

CLINICAL RELEVANCE

The results suggested the algorithm could be helpful when a radiologic evaluation owing to a lengthy waiting period cannot be performed in time, especially in situations when an early operation could be beneficial. It could help orthopaedic surgeons to decide whether to intervene palliatively or extensively, even when the surgical indication is clear.

Intramedullary nailing versus plate compound osteosynthesis in subtrochanteric and diaphyseal pathologic femoral fractures: a retrospective cohort study

PURPOSE

Pathologic fractures of the extremities due to carcinoma metastases require individual and patient prognosis-related stabilization procedures. Quick remobilization of the patient to restore the quality of life is of high importance, especially in the case of subtrochanteric and diaphyseal femoral fractures. In our retrospective cohort study, we evaluated intraoperative blood loss, length of operation, complication rate, and regain of lower extremity function in plate compound osteosynthesis (PCO) versus intramedullary nailing (IM) for subtrochanteric and diaphyseal pathologic fractures of the femur.

METHODS

Between January 2010 and July 2021, we retrospectively reviewed 49 patients who were treated at our institution for pathologic fractures of the subtrochanteric and diaphyseal femurs for group differences in terms of blood loss, length of operation, implant survival, and Musculoskeletal Tumor Society (MSTS) score.

RESULTS

We included 49 stabilization procedures of the lower extremity due to pathologic fractures of the proximal or diaphyseal femur, with a mean follow-up of 17.7 months. IM (n = 29) had a significantly shorter operation time than PCO (n = 20) (112.4 ± 9.4 and 163.3 ± 15.96 min, respectively). We did not detect any significant differences in terms of blood loss, complication rate, implant survival, or MSTS score.

CONCLUSION

Based on our data, pathologic subtrochanteric and diaphyseal fractures of the femur can be stabilized with IM, which has a shorter operation time than PCO, but the complication rate, implant survival, and blood loss remain unaffected.

Defining Cephalomedullary Nail Breakage Rates: A Systematic Review and Meta-Analysis

OBJECTIVE

To establish the background rate of breakage of cephalomedullary nails.

DATA SOURCES

MEDLINE, PubMed, and Web of Science were searched on April 3, 2023.

STUDY SELECTION

All English-language studies that examined trochanteric with or without subtrochanteric fractures and identified cephalomedullary nail breakage as an outcome measure and a breakage rate could be derived were included. Implants captured were predominantly the TFNA, TFN, and PFN by DePuy Synthes, various versions of the Gamma nail by Stryker, the Zimmer Natural Nail by Zimmer Biomet, and the Intertan by Smith and Nephew.

DATA EXTRACTION

The author, year of publication, dates of implant insertion, study design, method of detection of breakages, implant used, number of implant breakages, number of implants inserted, breakage rate, and follow-up were extracted.

DATA SYNTHESIS

Meta-analysis of included studies used descriptive nonparametric statistics and a noncomparative proportion for the pooled result. Differences in results between study design types were compared using the mean breakage rate per study design.

CONCLUSIONS

Cephalomedullary nail breakage is a rare complication with a median reported rate of 0.6% and a pooled result rate of 0.4%. Ninety-five percent of studies had a breakage rate of 1.3% or less, which sets a benchmark from the reported literature for future studies. There is wide variability in rates of breakage reported between different types of study designs with single-center review studies reporting breakage rates nearly 4-fold greater than large-scale administrative database reviews. The rate of implant breakage should not be used in isolation to judge an implant's performance.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Surgical Management of Metastatic Pathologic Subtrochanteric Fractures: Treatment Modalities and Associated Outcomes

BACKGROUND

Subtrochanteric pathological fractures (PFs) occur in approximately one-third of femur bone metastases. We seek to analyze surgical treatment strategies for subtrochanteric metastatic PFs and their revision rates.

METHODS

A systematic review was performed using the PubMed and Ovid databases. Reoperations as a result of complications were analyzed according to initial treatment modality, primary tumor site, and type of revision procedure.

RESULTS

We identified a total of 544 patients, 405 with PFs and 139 with impending fractures. The study population's mean age was 65.85 years with a male/female ratio of 0.9. Patients with subtrochanteric PFs who underwent an intramedullary nail (IMN) procedure (75%) presented a noninfectious revision rate of 7.2%. Patients treated with prosthesis reconstruction (21%) presented a noninfectious revision rate of 8.9% for standard endoprostheses and 2.5% for tumoral endoprostheses (p < 0.001). Revision rates because of infection were 2.2% for standard and 7.5% for tumoral endoprostheses. There were no infections within the IMN and plate/screws group (p = 0.407). Breast was the most common primary tumor site (41%) and had the highest revision rate (14.81%). Prosthetic reconstructions were the most common type of revision procedure.

CONCLUSION

No consensus exists regarding the optimal surgical approach in patients with subtrochanteric PFs. IMN is a simpler, less invasive procedure, ideal for patients with a shorter survival. Tumoral prostheses may be better suited for patients with longer life expectancies. Treatment should be tailored considering revision rates, patient's life expectancy, and surgeon's expertise.

LEVEL OF EVIDENCE

Level III. See Instructions for Authors for a complete description of levels of evidence.

Is the association of electrochemotherapy and bone fixation rational in patients with bone metastasis?

BACKGROUND

Bone metastases are frequent in patients with cancer. Electrochemotherapy (ECT) is a minimally invasive treatment based on a high-voltage electric pulse combined with an anticancer drug. Preclinical and clinical studies supported the use of ECT in patients with metastatic bone disease, demonstrating that it does not damage the mineral structure of the bone and its regenerative capacity, and that is feasible and efficient for the treatment of bone metastases. Year 2014 saw the start of a registry of patients with bone metastases treated with ECT, whose data are recorded in a shared database.

QUESTIONS/PURPOSES

(1) Among patients who underwent ECT and internal fixation for bone metastasis, how many experienced a reduction of pain? (2) How many cases showed a radiological response? (3) How many patients presented local or systemic complication after ECT and fixation?

PATIENTS AND METHODS

Patients were treated in Bologna at Rizzoli Orthopaedic Institute between March 2014 and February 2022 and recorded in the REINBONE registry (a shared database protected by security passwords): clinical and radiological information, ECT session, adverse events, response, quality of life indicators, and duration of follow-up were registered. We consider only cases treated with ECT and intramedullary nail during the same surgical session. Patients included in the analysis were 32: 15 males and 17 females, mean age 65 ± 13 years (median 66, range 38-88 years), mean time since diagnosis of primary tumor 6.2 ± 7.0 years (median 2.9, range 0-22 years). Nail was indicated in 13 cases for a pathological fracture in, 19 for an impending fracture. Follow-up was available for 29 patients, as 2 patients were lost to follow-up and 1 was unable to return to controls. Mean follow-up time was 7.7 ± 6.5 months (median 5, range 1-24), and 16 patients (50%) had a follow-up longer than 6 months.

RESULTS

A significant decrease in pain intensity was observed at the mean Visual Numeric Scale after treatment. Bone recovery was observed in 13 patients. The other 16 patients remained without changes, and one presented disease progression. One patient presented a fracture occurrence during the ECT procedure. Among all patients, bone recovery was observed in 13 patients: complete recovery in 1 patient (3%) and partial recovery in 12 patients (41%). The other 16 patients remained without changes, and one presented disease progression. One patient presented a fracture occurrence during the ECT procedure. However, healing was possible with normal fracture callus quality and healing time. No other local or systemic complications were observed.

CONCLUSION

We found that pain levels decreased after treatment in 23 of the 29 cases for a pain relief rate of 79% at final follow-up. Pain is one of the most important indicators of quality of life in patients that undergo palliative treatments. Even if conventional external body radiotherapy is considered a noninvasive treatment, it presents a dose-dependent toxicity. ECT provides a chemical necrosis preserving osteogenic activity and structural integrity of bone trabeculae; this is a crucial difference with other local treatments and allows bone healing in case of pathological fracture. The risk of local progression in our patient population was small, and 44% experienced bone recovery while 53% of the cases remained unchanged. We observe intraoperative fracture in one case. This technique, in selected patients, improves outcome in bone metastatic patients combing both the efficacy of the ECT in the local control of the disease and the mechanical stability with the bone fixation to synergize their benefits. Moreover, the risk of complication is very low. Although encouraging data, comparative studies are required to quantify the real efficacy of the technique. Level of Evidence Level I, therapeutic study.

Single-Stage versus Multi-Stage Intramedullary Nailing for Multiple Synchronous Long Bone Impending and Pathologic Fractures in Metastatic Bone Disease and Multiple Myeloma

PURPOSE

Determine whether perioperative outcomes differ between patients who have undergone single or multi-stage IMN procedures for impending or completed pathologic fractures.

METHODS

Patients were classified into single-stage single-bone (SSSB), single-stage multiple-bone (SSMB), and multi-stage multiple-bone (MSMB) based on procedure timing and number of bones involved. Outcome variables compared included length of stay (LOS), in-hospital mortality and survival, initiation of rehabilitation and adjuvant therapy, and perioperative complications.

RESULTS

There were 272 IMNs placed in 181 patients (100 males, 81 females, 55.2% and 44.8%, respectively) with a mean age of 66.3 ± 12.1 years. MSMB had significantly longer LOS (24.3 ± 14.2 days) and rehabilitation initiation (3.4 ± 2.5 days) compared to SSSB (8.5 ± 7.7 and 1.8 ± 1.6 days) and SSMB (11.5 ± 7.6 and 2.0 ± 1.6 days) subjects, respectively (both; p < 0.01). Although total perioperative complication rates in SSMB and MSMB were comparable (33.3% vs. 36.0%), they were significantly higher than SSSB (18%) (p = 0.038). MSMB had significantly more (20%) cardiopulmonary complications than SSMB (11.1%) and SSSB (4.5%) (p = 0.027). All groups exhibited comparative survivorship (8.1 ± 8.6, 7.1 ± 7.2, and 11.4 ± 11.8 months) and in-hospital mortality (4.5%, 8.9%, and 4.0%) (all; p > 0.05).

CONCLUSION

In comparison to MSMB, SSMB intramedullary nailing did not result in higher perioperative complication or in-hospital mortality rates in select patients with synchronous long-bone metastases but led to earlier postoperative discharge and initiation of rehabilitation.

Fixation Principles for Pathologic Fractures in Metasatic Disease

The management of pathologic fractures differs from nonpathologic fractures with respect to preoperative evaluation, surgical strategies, adjuvant therapies, and complication rates. These issues must be understood to provide appropriate musculoskeletal care for patients with metastatic disease.

Demographic and clinical profile of patients treated with proximal femoral nails - a 10-year analysis of more than 40,000 Cases

Background

Hip fractures are common in elderly populations and can be life threatening. Changes in healthcare delivery and outcomes for patients with hip fracture treated with intramedullary nails are not well characterized. The objectives of our study were: 1) the characterization of patients treated with the Trochanteric Fixation Nail -Advanced™(TFNA) Proximal Femoral Nailing System or comparable nails (index) and estimate 12-month all-cause readmissions (ACR) and reoperations following index; and 2) the evaluation of 10-year healthcare utilization (HCU) trends for treatment of femoral fractures with femoral nails.

Methods

This is a retrospective database analysis using the Premier hospital database. All adults with femoral fracture treated with an intramedullary nail, from 2010 to Q3 2019, in the inpatient setting, were identified. Exclusion criteria included patients with bilateral hip surgery and presence of breakage at time of initial surgery. The primary outcome was ACR and reoperation, the secondary outcomes were healthcare utilization metrics. Variables included demographics, comorbidities (Elixhauser Index (EI)), surgical intervention variables and hospital characteristics.

Results

Forty-one thousand one hundred four patients were included in the study, of which 14,069 TFNA patients, with average age 77.9 (Standard deviation (SD): 12.0), more than 60% with 3 or more comorbidities (more than 64% for TFNA), 40% with severe or extreme disease severity and one third with severe or extreme risk for mortality. ACR reached 60.1% (95% confidence interval (CI): 59.6%-60.5%) – for TFNA: 60.0% (95%CI: 59.2%-60.8%). The reoperation rate was 4.0% (95%CI: 3.8%-4.2%) – for TFNA: 3.8% (95%CI: 3.5%-4.1%). Length of stay (LOS) averaged 5.8 days (SD: 4.8), and 12-month hip reoperation was 4.0% (3.8%-4.2%), in TFNA cohort: 3.8% (3.5%-4.1%). From 2010 to 2019: the percentage patients operated within 48 h of admission significantly increased, from 75.2% (95%CI: 74.3%-76.1%) to 84.3% (95%CI: 83.9%-84.6%); LOS significantly decreased, from 6.2 (95%CI: 6.0–6.4) to 5.6 (95%CI: 5.5–5.7) days; discharge to skilled nursing facilities (SNF) increased from 56.0% (95%CI: 54.8%-57.2%) to 61.5% (95%CI: 60.8%-62.2%); ACR rates decreased but reoperation rates remained constant.

Conclusions

ACR and reoperation rates were similar across device types and averaged 60.1% and 4.0%, respectively. Ten-year analyses showed reductions in hospital HCU and greater reliance on SNF.

What Factors Are Associated With Local Metastatic Lesion Progression After Intramedullary Nail Stabilization?

BACKGROUND

Pathologic fracture of the long bones is a common complication of bone metastases. Intramedullary nail stabilization can be used prophylactically (for impending fractures) or therapeutically (for completed fractures) to preserve mobility and quality of life. However, local disease progression may occur after such treatment, and there is concern that surgical instrumentation and the intramedullary nail itself may seed tumor cells along the intramedullary tract, ultimately leading to loss of structural integrity of the construct. Identifying factors associated with local disease progression after intramedullary nail stabilization would help surgeons predict which patients may benefit from alternative surgical strategies.

QUESTIONS/PURPOSES

(1) Among patients who underwent intramedullary nail stabilization for impending or completed pathologic fractures of the long bones, what is the risk of local progression, including progression of the existing lesion and development of a new lesion around the nail? (2) Among patients who experience local progression, what proportion undergo reoperation? (3) What patient characteristics and treatment factors are associated with postoperative local progression? (4) What is the difference in survival rates between patients who experienced local progression and those with stable local disease?

METHODS

Between January 2013 and December 2019, 177 patients at our institution were treated with an intramedullary nail for an impending or completed pathologic fracture. We excluded patients who did not have a pathologic diagnosis of metastasis before fixation, who were younger than 18 years of age, who presented with a primary soft tissue mass that eroded into bone, and who experienced nonunion from radiation osteitis or an avulsion fracture rather than from metastasis. Overall, 122 patients met the criteria for our study. Three fellowship-trained orthopaedic oncology surgeons involved in the care of these patients treated an impending or pathologic fracture with an intramedullary nail when a long bone lesion either fractured or was deemed to be of at least 35% risk of fracture within 3 months, and in patients with an anticipated duration of overall survival of at least 6 weeks (fractured) or 3 months (impending) to yield palliative benefit during their lifetime. The most common primary malignancy was multiple myeloma (25% [31 of 122]), followed by lung carcinoma (16% [20 of 122]), breast carcinoma (15% [18 of 122]), and renal cell carcinoma (12% [15 of 122]). The most commonly involved bone was the femur (68% [83 of 122]), followed by the humerus (27% [33 of 122]) and the tibia (5% [6 of 122]). A competing risk analysis was used to determine the risk of progression in our patients at 1 month, 3 months, 6 months, and 12 months after surgery. A proportion of patients who ultimately underwent reoperation due to progression was calculated. A univariate analysis was performed to determine whether lesion progression was associated with various factors, including the age and sex of the patient, use of adjuvant therapies (radiation therapy at the site of the lesion, systemic therapy, and antiresorptive therapy), histologic tumor type, location of the lesion, and fracture type (impending or complete). Patient survival was assessed with a Kaplan-Meier curve. A p value < 0.05 was considered significant.

RESULTS

The cumulative incidence of local tumor progression (with death as a competing risk) at 1 month, 3 months, 6 months, and 12 months after surgery was 1.9% (95% confidence interval 0.3% to 6.1%), 2.9% (95% CI 0.8% to 7.5%), 3.9% (95% CI 1.3% to 8.9%), and 4.9% (95% CI 1.8% to 10.3%), respectively. Of 122 patients, 6% (7) had disease progression around the intramedullary nail and 0.8% (1) had new lesions at the end of the intramedullary nail. Two percent (3 of 122) of patients ultimately underwent reoperation because of local progression. The only factors associated with progression were a primary tumor of renal cell carcinoma (odds ratio 5.1 [95% CI 0.69 to 29]; p = 0.03) and patient age (difference in mean age 7.7 years [95% CI 1.2 to 14]; p = 0.02). We found no associations between local disease progression and the presence of visceral metastases, other skeletal metastases, radiation therapy, systemic therapy, use of bisphosphonate or receptor activator of nuclear factor kappa-B ligand inhibitor, type of fracture, or the direction of nail insertion. There was no difference in survivorship curves between those with disease progression and those with stable local disease (= 0.36; p = 0.54).

CONCLUSION

Our analysis suggests that for this population of patients with metastatic bone disease who have a fracture or impeding fracture and an anticipated survival of at least 6 weeks (completed fracture) or 3 months (impending fracture), the risk of experiencing local progression of tumor growth and reoperations after intramedullary nail stabilization seems to be low. Lesion progression was not associated with the duration of survival, although this conclusion is limited by the small number of patients in the current study and the competing risks of survival and local progression. Based on our data, patients who present with renal cell carcinoma should be cautioned against undergoing intramedullary nailing because of the risk of postoperative lesion progression.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Tips and tricks to avoid implant failure in proximal femur fractures treated with cephalomedullary nails: a review of the literature

Objective:

To describe the surgical aspects potentially contributing to hardware failure of cephalomedullary nails.

Data Sources:

A search of the Embase, PubMed (MEDLINE), Web of Science, and the Cochrane library for reports of hardware failures after intramedullary fixation of proximal femur fractures. Issues of cut out and cut through phenomena related to technique were excluded. Expert opinion of 3 surgeons, each trained on several fixation systems at Level | trauma centers is reported.

Data Extraction:

Three authors extracted data using a predesigned form. Implant type, reported failure mechanism, and associated factors with implant failure were recorded as well as potential bias.

Results:

Of 2182 search results screened, 64 articles were deemed relevant for our research question and were included. The authors identified factors associated with implant failure: preoperative patient and fracture characteristics, intraoperative reduction, implant handling, and postoperative nonunion. Issues were identified as independent modifiable intraoperative risk factors: inadequate fracture reduction, varus position of femoral neck, direct damage of the cephalomedullary nail aperture by eccentric drilling related to guide sleeve handling, and implant design mechanism failures.

Conclusions:

Multiple factors associated with intraoperative handling can influence the healing of proximal femur fractures. Although many of these have been well described and are taught in fracture courses, surgeons should be aware of subtle intraoperative complications reported in the literature that can weaken implants and add to the likelihood of early failure.

Level of Evidence: IV

The Surgical Management of Proximal Femoral Metastases: A Narrative Review

The proximal femur is a common location for the development of bony metastatic disease. Metastatic bone disease in this location can cause debilitating pain, pathologic fractures, reduced quality of life, anemia or hypercalcemia. A thorough history, physical examination and preoperative investigations are required to ensure accurate diagnosis and prognosis. The goals of surgical management is to provide pain relief and return to function with a construct that provides stability to allow for immediate weightbearing. Current surgical treatment options include intramedullary nailing, hemiarthroplasty or total hip arthroplasty and endoprosthetic reconstructions. Oligometastatic renal cell carcinoma must be given special consideration as tumor resection and reconstruction has survival benefit. Both tumor and patient characteristics must be taken into account before deciding on the appropriate surgical intervention.

Treatment of Pathologic Peritrochanteric Fractures Using Sliding Hip Screws Augmented with Cerclage Reconstruction Plates

We proposed a new method to augment the traditional sliding hip screw (SHS) with cerclage reconstruction plates to treat pathologically impending and actual peritrochanteric fractures as well as to revise open reductions and internal fixations to increase the construct strength against the shearing force, thus reducing the implant failure rate. In this retrospective study, patients with peritrochanteric pathology with at least two years of follow-up who underwent augmentation with cerclage reconstruction plates (modified SHS) and conventional SHS between 1 May 2015 and 31 May 2017 were divided into groups A (n = 12) and B (n = 28), respectively. Demographic data, surgery duration, blood loss, complications, and local radiotherapy were analyzed. The average surgery duration was significantly longer in group A (p = 0.013). The estimated intraoperative and perioperative blood losses were not significantly different between the groups. The implant survival rates were not significantly different under competing risk analysis. The success rate of a revision surgery with modified SHS was excellent, and implant survival time was >2 years, as observed with the previous SHS constructs. Subtrochanteric region involvement and a postoperative visual analog scale ≥4 could be risk factors of implant failure and revision surgery. This technique can be an alternative treatment for difficult pathologic peritrochanteric fractures, especially those with previous plating failure.

Bone Metastatic Breast Cancer: Advances in Cell Signaling and Autophagy Related Mechanisms

Bone metastasis is a frequent complication of breast cancer with nearly 70% of metastatic breast cancer patients developing bone metastasis during the course of their disease. The bone represents a dynamic microenvironment which provides a fertile soil for disseminated tumor cells, however, the mechanisms which regulate the interactions between a metastatic tumor and the bone microenvironment remain poorly understood. Recent studies indicate that during the metastatic process a bidirectional relationship between metastatic tumor cells and the bone microenvironment begins to develop. Metastatic cells display aberrant expression of genes typically reserved for skeletal development and alter the activity of resident cells within the bone microenvironment to promote tumor development, resulting in the severe bone loss. While transcriptional regulation of the metastatic process has been well established, recent findings from our and other research groups highlight the role of the autophagy and secretory pathways in interactions between resident and tumor cells during bone metastatic tumor growth. These reports show high levels of autophagy-related markers, regulatory factors of the autophagy pathway, and autophagy-mediated secretion of matrix metalloproteinases (MMP's), receptor activator of nuclear factor kappa B ligand (RANKL), parathyroid hormone related protein (PTHrP), as well as WNT5A in bone metastatic breast cancer cells. In this review, we discuss the recently elucidated mechanisms and their crosstalk with signaling pathways, and potential therapeutic targets for bone metastatic disease.

Bent or broken: analysis of set screw fracture in the TFNa implant

Objectives

To evaluate set screw fracture in the Trochanteric Femoral Nail Advanced implant (TFNa, Synthes, West Chester, PA) and to identify additional mechanisms of set screw failure in the TFNa.

Materials and methods

Patients who had experienced failure after open reduction and internal fixation (ORIF) with the TFNa were identified. TFNa implants were explanted and inspected following revision surgery. Medical device reports (MDRs) and manufacturer’s inspection reports describing similar failures for the TFNa in the United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database were also reviewed.

Results

Four set screw fractures that occurred at a level II trauma center were observed. Sixty-seven reported failures were identified in the MAUDE database for review. Twenty-eight failed implants were returned to the manufacturer for inspection with a published inspection report available for analysis. Set screw fractures can occur in the TFNa when the set screw is deployed prematurely into the proximal screw aperture prior to blade/screw insertion. The set screw can also bend and deform if it is advanced against a helical blade/lag screw that is not fully seated into position, thereby potentially compromising its function.

Conclusion

The TFNa set screw allows for potential fracture during implant insertion leading to uncontrolled collapse, early excessive proximal femoral shortening, and rotational instability of the helical blade/lag screw. Similar failures in the TFNa can be prevented by having the surgeon inspect the proximal screw aperture after attachment of the proximal aiming aim to ensure the set screw has not been deployed prematurely.

Level of evidence

Therapeutic Level III.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10195-021-00594-8.

Intramedullary Nail Breakage and Mechanical Displacement in Patients with Proximal Femoral Fractures: A Commercial and Medicare Supplemental Claims Database Analysis

Objective

This study evaluated the rates and patterns of intramedullary nail (IMN) breakage and mechanical displacement for proximal femur fractures and the factors associated with their occurrence.

Patients and Methods

Patients with subtrochanteric, intertrochanteric, or basicervical femoral neck fractures treated with IMN from 2016 to 2019 were identified from commercial and Medicare supplemental claims databases and were followed for up to two years. Kaplan–Meier analysis estimated the cumulative incidence of and patterns of breakage/mechanical displacement. Multivariable Cox regression models evaluated the factors associated with breakage/mechanical displacement.

Results

A total of 11,128 patients had IMN fixation for subtrochanteric, intertrochanteric, or basicervical femoral neck fractures: (mean SD) age 75.6 (16.4) years, 66.2% female, 74.3% Medicare supplemental vs 26.7% commercial insurance. Comorbidities included hypertension (62.9%), osteoporosis (27.3%), cardiac arrhythmia (23.1%), diabetes (30.7%), and chronic pulmonary disease (16.3%). Most fractures were closed (97.2%), intertrochanteric or basicervical femoral neck (80.1%), and not pathological (91.0%). The cumulative incidence of nail breakage over two years was 0.66% overall, 1.44% for combination fractures, 1.16% for subtrochanteric fractures, and 0.49% for intertrochanteric or basicervical fractures. The cumulative incidence of mechanical displacement was 0.37% overall, 0.43% for subtrochanteric fractures, 0.42% for combination fractures, and 0.36% for intertrochanteric or basicervical femoral neck fractures. Half of the breakages occurred within five months after surgery and half of the mechanical displacements occurred within 75 days. Age 50–64 (vs 75+) and subtrochanteric or pathological fracture were more commonly associated with nail breakage. Complicated hypertension was more commonly associated with mechanical displacement.

Conclusion

The incidence of IMN breakage and mechanical displacement in US commercial and Medicare supplemental patients with proximal femur fractures from 2016 to 2019 was low (0.66% and 0.37%, respectively up to two years). Age 50–64 (vs 75+) and subtrochanteric or pathological fracture were more commonly associated with breakage. Complicated hypertension was associated with mechanical displacement.

Comparison of Early Fatigue Failure of the TFNa and Gamma 3 Cephalomedullary Nails in the United States From 2015 to 2019

OBJECTIVES

To compare reports of implant fatigue failure submitted to the FDA of 2 commonly used cephalomedullary nails.

METHODS

In total, 2724 medical device reports from the FDA's MAUDE database from Jan 2015 to Oct 2019 were reviewed for the Trochanteric Femoral Nail-Advanced (TFNa) and Gamma 3 implants.

RESULTS

Data from 342 implant failures included in the MAUDE database were analyzed. TFNa and Gamma 3 had 183 and 159 reported fatigue failures, respectively. All failed implants fractured in the same location through the proximal screw aperture. Time from implantation to failure was on average 2 months shorter for TFNa implants that were reported fractured than for Gamma 3 implants reported, a difference that was statistically significant (P < 0.05). In total, 100 implants were reported to have failed within the first 4 months (53 and 47 for TFNa and Gamma 3, respectively). For Gamma 3 implants that failed in the first 4 months, almost all of the available manufacturers' inspection reports revealed implant notches at the point of failure from drilling. For TFNa implants that failed early, only one reported notch was noted in the available inspection reports.

CONCLUSIONS

In contrast to other studies regarding fatigue failure, reported failures in both TFNa and Gamma 3 occurred earlier than can be attributed to delayed or nonunion. The reported failures of the TFNa in the MAUDE database occurred earlier than did those of the Gamma 3. Early failures of the Gamma 3 seemed to be the result of iatrogenic implant notching.

LEVEL OF EVIDENCE

Therapeutic Level III. See instructions for authors for a complete description of levels of evidence.

C-reactive protein and tumour diagnosis predict survival in patients treated surgically for long bone metastases

PURPOSE

Surgical options for long bone metastases include intramedullary nail fixation or prosthetic reconstruction. Patients with a short life expectancy may benefit from less invasive surgery such as intramedullary nail fixation, while patients with a long life expectancy could be treated with more invasive surgery such as prosthetic reconstruction. The purpose of our study was to analyze the survival of patients treated surgically for long bone metastases, determining the prognostic factors affecting survival and analyzing the surgical complications and reoperation rates. Based on our results, we developed a prognostic score that helps to choose the best treatment for these patients. In addition, we compared the performance of our prognostic score with other previous prognostic models.

METHOD

We investigated prospectively potential clinical and laboratory prognostic factors in 159 patients with metastatic bone disease who underwent surgery with intramedullary nail fixation or prosthetic reconstruction. Clinical data were collected, recording the following data: age and sex of patients, primary tumour and time of diagnosis, number (single or multiple) and presentation (synchronous or metachronous) of bone metastases, presence of visceral metastases. The following laboratory data were analyzed: hemoglobin, leukocyte counts, lymphocyte counts, platelets count, alkaline phosphatase, and C-reactive protein.

RESULTS

Our study showed that pathological C-reactive protein and primary tumour diagnosis were significant negative independent prognostic factors at 12-month survival. Based on our results, we created a score using C-reactive protein and primary tumour diagnosis, creating three different prognostic groups: (A) good prognosis primary tumour and physiological CRP with probability of survival at 12 months of 88.9 [80.1-98.5]; (B) bad prognosis primary tumour and physiological CRP or good prognosis primary tumour and pathological CRP with a probability of survival at 12 months of 56.7 [45.4-70.7]; (C) bad prognosis primary tumour and pathological CRP with a probability of survival at 12 months of 12.5 [5.0-28.3]. Using ROC multiple analysis, our score (AUC = 0.816) was the most accurate in predicting a 12-month survival compared to previous prognostic models.

DISCUSSION

Patients treated surgically for long bone metastases with a life expectancy over 12 months should be treated with more durable reconstruction, while patients with a life expectancy less than 12 months should be treated with less invasive surgery. The diagnosis of primary cancer and C-reactive protein are two very simple data which every orthopaedic surgeon in any community hospital can easily rely on for any decision-making in the surgical treatment of a complex patient as with a patient with skeletal metastases.

CONCLUSION

Our prognostic score based on only two simple variables (C-reactive protein and primary tumour diagnosis) was able to predict the 12-month survival of patients treated surgically for long bone metastases and could be helpful in choosing the best treatment for these patients.

Utility of the Current Procedural Terminology Codes for Prophylactic Stabilization for Defining Metastatic Femur Disease

INTRODUCTION

Cohorts from the electronic health record are often defined by the Current Procedural Terminology (CPT) codes. The error prevalence of CPT codes for patients receiving surgical treatment of metastatic disease of the femur has not been investigated, and the predictive value of coding ontologies to identify patients with metastatic disease of the femur has not been adequately discussed.

METHODS

All surgical cases at a single academic tertiary institution from 2010 through 2015 involving prophylactic stabilization of the femur or fixation of a pathologic fracture of the femur were identified using the CPT and International Classification of Disease (ICD) codes. A detailed chart review was conducted to determine the procedure performed as documented in the surgical note and the patient diagnosis as documented in the pathology report, surgical note, and/or office visit notes.

RESULTS

We identified 7 CPT code errors of 171 prophylactic operations (4.1%) and one error of 71 pathologic fracture fixation s(1.4%). Of the 164 prophylactic operations that were coded correctly, 87 (53.0%) had metastatic disease. Of the 70 pathologic operations that were coded correctly, 41 (58%) had metastatic disease.

DISCUSSION

The error prevalence was low in both prophylactic stabilization and pathologic fixation groups (4.1% and 1%, respectively). The structured data (CPT and ICD-9 codes) had a positive predictive value for patients having metastatic disease of 53% for patients in the prophylactic stabilization group and 58% for patients in the pathologic fixation group. The CPT codes and ICD codes assessed in this analysis do provide a useful tool for defining a population in which a moderate proportion of individuals have metastatic disease in the femur at an academic medical center. However, verification is necessary.

A new perspective towards failure of gamma nail systems

Uncommon causes of nail failures and surgical reinterventions were determined. The study included 23 osteoporotic patients, 13 of whom followed a fast recovery program with early walking (FWB group). The other 10 patients were not allowed full weight bearing until 6 weeks (NFWB group). The T-score was determined before surgery for all cases. A case with a nail breakage after a failed DCS implant fixed in another clinic was also analyzed. The nail was revised and the broken implant underwent a metallurgic and microscopic examination. The average T-score was 2.5 for the patients that followed the fast recovery program and 2.7 for the patients from non-full weight bearing. Four patients, 1 from the NFWB group and 3 from FWB group, presented a screw cut-out. It was found that the errors of the guiding instruments may create dents, scratches or micro-fractures on the titanium coating that lead to an early implant failure. Imperfect reduction leads to incorrect implant placement and a high incidence of failure. Damaging the titanium protective coating, in a low force, high cycles scenario can cause structural failure. Delays in fracture healing and material fatigue are the most common causes of nail failure and can lead to catastrophic complications.

Surgical management of proximal femoral metastasis: Fixation or hip replacement? A 309 case series

INTRODUCTION

The proximal femur is the most frequent operative site for metastasis, but there is no consensus between internal fixation and hip replacement. The present multicenter retrospective observational study sought: (1) to compare early clinical results between internal fixation and hip replacement for proximal femoral metastasis (PFM), and (2) to assess events affecting survival.

HYPOTHESIS

The study hypothesis was that internal fixation and hip replacement give comparable clinical results, operative site complications rates and survival.

MATERIAL AND METHODS

The series comprised 309 cases, 10 of which were bilateral, in 182 females and 117 males, with a mean age of 67.2±11.5 years and 62.5±13.2 years, respectively. Primaries were mainly breast (118; 38.2%), lung (85; 25.5%) or kidney (40; 12.9%). PFM was revelatory in 114 cases (36.9%). There was visceral involvement in 142 patients (46%), multiple peripheral bone involvement in 212 (68.6%), and spinal involvement in 134 (43.4%). There were 124 pathologic fractures (40%), 51 of which were revelatory. Metastases were cervicocephalic in 135 cases (43.7%), metaphyseal in 166 (53.7%) and both in 8 (2.6%). PFM was osteolytic in 90% of cases, managed by hip replacement in 161 cases and internal fixation in 148 (12 screwed plates, 136 nails). Seventy-seven patients had postoperative radiation therapy.

RESULTS

After hip replacement (n=144), walking was normal in 35 cases (24.3%), impaired but unassisted in 53 (36.8%), with 1 forearm crutch in 24 (16.6%), 2 crutches or a frame in 26 (18%), and impossible in 6 (4.1%). After nailing (n=125), results were respectively 38 (30.4%), 47 (37.6%), 15 (12%), 18 (14.4) and 7 (5.6%). Recovery of normal walking capacity did not significantly differ according to technique (p=0.162); nor did pain or function. Recovery of normal walking capacity was better after preventive surgery (p<0.001). Perioperative complications comprised: 10 cases of severe blood loss, 7 pulmonary embolisms, 6 digestive hemorrhages, and 5 lung infections. Secondarily, there were 11 infections (7 after hip replacement, 2 after nailing, 2 after plate fixation), 7 progressive osteolyses and 5 fractures. Complications rates were significantly higher with plate fixation, with no difference between nailing and hip replacement. Survival did not significantly differ between hip replacement (12 months [95% CI: 7-19]), nailing (7 months [95% CI: 6-11]) and plate fixation (16 months [95% CI: 6-not calculable]).

CONCLUSIONS

Clinical results and survival were comparable between hip replacement and nailing, confirming the study hypothesis, in agreement with the literature. Each technique has its indications. Patients with severely impaired walking capacity benefited greatly from surgery. The importance of preventive surgery was highlighted.

LEVEL OF EVIDENCE

IV, retrospective study.

The effects of metastatic lesion on the structural determinants of bone: Current clinical and experimental approaches

Metastatic bone disease is incurable with an associated increase in skeletal-related events, particularly a 17-50% risk of pathologic fractures. Current surgical and oncological treatments are palliative, do not reduce overall mortality, and therefore optimal management of adults at risk of pathologic fractures presents an unmet medical need. Plain radiography lacks specificity and may result in unnecessary prophylactic fixation. Radionuclide imaging techniques primarily supply information on the metabolic activity of the tumor or the bone itself. Magnetic resonance imaging and computed tomography provide excellent anatomical and structural information but do not quantitatively assess bone matrix. Research has now shifted to developing unbiased data-driven tools that can predict risk of impending fractures and guide individualized treatment decisions. This review discusses the state-of-the-art in clinical and experimental approaches for prediction of pathologic fractures with bone metastases. Alterations in bone matrix quality are associated with an age-related increase in skeletal fragility but the impact of metastases on the intrinsic material properties of bone is unclear. Engineering-based analyses are non-invasive with the capability to evaluate oncological treatments and predict failure due to the progression of metastasis. The combination of these approaches may improve our understanding of the underlying deterioration in mechanical performance.

Evaluating the reoperation rate and hardware durability of three stabilizing implants for 105 malignant pathologic humerus fractures

INTRODUCTION

Many patients sustaining a malignant pathologic humerus fracture (MPHF) elect for surgical stabilization. Complications prompting reoperation can occur, leading to additional quality of life and financial cost. One common event preceding reoperation is a broken implant (BI). The purpose of this study was to identify the rate of reoperation following surgical stabilization of MPHF with three techniques - photodynamic bone stabilization (PBS), intramedullary nail (IMN), and cemented plate fixation (CPF) - and estimate to what extent improved implant durability might prevent reoperation.

MATERIALS AND METHODS

Retrospective data collection was performed, identifying 105 procedures (100 patients) who underwent non-articular MPHF surgery from 2010-2016: 19 PBS, 65 IMN, 21 CPF. All patients were followed for at least two years or until death.

RESULTS

Reoperation rates were similar at one year (10.5%,6.2%,4.8%, p = 737), two years (15.8%,6.2%,9.5%, p = 375), and final evaluation (15.8%,7.7%,14.3%, p = 248). The rate of BI for PBS, IMN, and CPF was 10.5%,0%, and 4.8% (p = 049 PBS/IMN) at one year, 15.8%,0%, and 9.5% (p = 010 PBS/IMN) at two years, and 15.8%,0%, and 14.3% (p = 010 IMN/PBS, p = 013 IMN/CPF) at final evaluation.

CONCLUSIONS

Reoperation rate was not significantly different at any time point. However, IMN surgery resulted in the lowest rate of broken implants (zero), statistically significant versus PBS at all time periods and versus CPF at final follow-up. PBS may eventually offer selected advantages for MPHF management, but current data suggests fragility must be thoughtfully considered.

Axial cortical involvement of metastatic lesions to identify impending femoral fractures; a clinical validation study

BACKGROUND AND PURPOSE

Patients with advanced cancer may develop painful bone metastases, potentially resulting in pathological fractures. Adequate fracture risk assessment is of key importance to prevent fracturing and maintain mobility. This study aims to validate the clinical reliability of axial cortical involvement with a 30 mm threshold on conventional radiographs to assess fracture risk in femoral bone metastases.

MATERIALS AND METHODS

All patients with bone metastases who received radiotherapy for pain included in two multicentre prospective studies were selected. Conventional radiographs obtained at a maximum of two months prior to radiotherapy were collected. Three experts independently measured lesions and scored radiographic characteristics. Sensitivity, specificity, positive (PPV) and negative predictive value (NPV) were calculated.

RESULTS

Hundred patients were included with a median follow-up of 23.0 months (95%CI: 10.6-35.5). Two fractures occurred in lesions with axial cortical involvement <30 mm, and 12 in lesions ≥30 mm. Sensitivity, specificity, PPV and NPV of axial cortical involvement for predicting femoral fractures were 86%, 50%, 20% and 96%, respectively. Patients with lesions ≥30 mm had a 5.3 times higher fracture risk than patients with smaller lesions.

CONCLUSION

Our validation study confirmed the use of 30 mm axial cortical involvement to assess fracture risk in femoral bone metastases. Until a more accurate and practically feasible method has been developed, this clinical parameter remains an easy method to assess femoral fracture risk to aid patients and clinicians to choose the optimal individual treatment modality.