What Factors Are Associated With Implant Revision in the Treatment of Pathologic Subtrochanteric Femur Fractures?

Limiting reoperation or revision after operative stabilization or endoprosthetic reconstruction of a pathologic subtrochanteric femur fracture reduces morbidity, but how best to achieve this remains controversial. Endoprosthetic reconstruction offers durable mechanical stability but may not be most appropriate in patients who are frail or who are not expected to survive more than a few months. For that reason, cumulative incidence survival (looking at the endpoint of reoperation or revision with death as a competing risk) and factors associated with revision after surgical stabilization or reconstruction-both of which remain poorly characterized to date-would help surgeons make better decisions on behalf of these patients. We analyzed patients who were operatively treated for pathologic subtrochanteric femur fracture, and we asked: (1) What is the cumulative incidence of reoperation and revision at 3 months, 1 year, and 2 years after surgery for pathologic subtrochanteric femur fracture in patients undergoing each treatment type with death as a competing risk? (2) What are the factors associated with implant revision after operative treatment of pathologic subtrochanteric femur fracture? (3) What is the overall survival of patients in this population after surgery? (4) How do clinical and surgical factors along with the frequency of complications compare in this population by operative treatment? Between January 2000 and December 2020, 422 patients underwent surgery for completed proximal femur pathologic fractures. After excluding patients with non-subtrochanteric femur fractures (71% [301]), fractures caused by primary tumors of bone (< 1% [2]), and insufficient data (1% [6]), we included 113 patients who underwent operative treatment of completed pathologic subtrochanteric femur fractures. Our study period spanned 20 years because although implant trends may have shifted, the overall operative objective for pathologic subtrochanteric femur fractures-restoring function and alleviating pain, regardless of the extent of bony union-have remained relatively unchanged during this period. Median follow-up time was 6 months (range 1 month to 20.6 years). Intramedullary nailing (IMN) was performed in 68% (77) of patients, proximal femur replacement (PFR) was performed in 19% (22), and open reduction and internal fixation (ORIF) was performed in 12% (14) of patients. IMN was performed in patients with a poor prognosis but in whom fracture stabilization was felt to be advantageous. In instances of complex fractures in which adequate reduction could not be achieved, ORIF was generally performed. PFR was generally performed in patients with a better prognosis in which long-term implant survival and patient function were prioritized. We found a higher proportion of women in the IMN group (73% versus 32% in PFR and 50% in ORIF; p = 0.001). Rapid growth tumors (Katagiri classification) were found in 25% of patients with IMN, 27% with PFR, and 43% with ORIF. The primary outcome was the cumulative incidence of reoperation or revision surgery after initial stabilization. Competing risk analysis with death as a competing event was performed to estimate the cumulative incidence for reoperation and revision. Factors associated with revision surgery were identified using the Cox proportional hazards model, which rendered HRs. All analyses were adjusted to control for potential confounders. The cumulative incidence for reoperation at 2 years was 5% (95% confidence interval [CI] 4% to 6%) for IMN, 15% (95% CI 9% to 22%) for PFR, and 32% (95% CI 15% to 50%) for ORIF (p = 0.03). The cumulative incidence for revision at 2 years was 4% (95% CI 3% to 4%) for IMN, 4% (95% CI 2% to 6%) for PFR, and 33% (95% CI 15% to 51%) for ORIF (p = 0.01). Factors associated with revision surgery were radioresistant tumor histology (HR 8.5 [95% CI 1.2 to 58.9]; p = 0.03) and ORIF (HR 6.3 [95% CI 1.5 to 27.0]; p = 0.01). The 3-month, 1-year, and 2-year overall survival was 80% (95% CI 71% to 87%), 35% (95% CI 26% to 45%), and 28% (95% CI 19% to 36%), respectively. Thirty-day postoperative complications did not differ by fixation type, but 90-day readmission was highest after ORIF (3 of 14 versus 4 of 22 in PFR and 4% [3 of 77] in IMN; p = 0.03) Periprosthetic joint infection (PJI) was more common after salvage PFR (2 of 6) than primary PFR (1 of 22) (p = 0.04). Primary PFR may be preferred for pathologic subtrochanteric femur fractures arising from radioresistant tumor types, as the cumulative incidence of revision was no different than for IMN while restoring function, alleviating pain, and offering local tumor control, and it less commonly develops PJI than salvage PFR. In complex fractures not amenable to IMN, surgeons should consider performing a PFR over ORIF because of the lower risk of revision and the added benefit of replacing the pathologic fracture altogether and offering immediate mechanical stability with a cemented endoprosthesis. Future studies might evaluate the extent of bone loss from local tumor burden, and this could be quantified and analyzed in future studies as a covariate as it may clarify when PFR is advantageous in this population. Level III, therapeutic study.

Leland CR ，Gonzalez MR ，Werenski JO ，Vallone AT ，Brighton KG ，Newman ET ，Lozano-Calderón SA ，Raskin KA ... -  《-》

Are There Differences in Performance Among Femoral Stem Brands Utilized in Cementless Hemiarthroplasty for Treatment of Geriatric Femoral Neck Fractures?

For the vast majority of displaced femoral neck fractures in older patients, cemented femoral fixation is indicated because it is associated with a lower risk of periprosthetic fracture than cementless fixation. Nevertheless, cementless fixation continues to be utilized with high frequency for hip fractures in the United States. It is therefore helpful to understand the performance of individual cementless brands and models. Although prior studies have compared femoral stems by design type or stem geometry, there may still be a difference in revision risk according to femoral stem brand given the potential differences within design groupings with regard to manufacturing, implantation systems, and implant design nuances among vendors. (1) Is there a difference in aseptic revision risk among femoral stem brands in patients ≥ 60 years of age who have displaced femoral neck fractures treated with cementless hemiarthroplasty? (2) Is there a difference in revision for periprosthetic fracture among femoral stem brands in patients ≥ 60 years of age with displaced femoral neck fractures treated with cementless hemiarthroplasty? A retrospective, comparative, large-database cohort study was conducted using data from Kaiser Permanente's Hip Fracture Registry. This integrated healthcare system covers more than 12 million members throughout eight regions in the United States; membership has been found to be representative of the general population in the areas served. The Hip Fracture Registry collects details on all patients who undergo hip fracture repair within the organization. These patients are then longitudinally monitored for outcomes after their repair, and all identified outcomes are manually validated through chart review. Patients ages ≥ 60 years who underwent unilateral hemiarthroplasty treatment of a displaced femoral neck fracture from 2009 to 2021 were identified (n = 22,248). Hemiarthroplasties for polytrauma, pathologic or open fractures, or patients who had additional surgeries at other body sites during the same stay, as well as those with prior procedures in the same hip, were excluded (21.4% [4768]). Cemented procedures and those with missing or inconsistent implant information (for example, cement used but cementless implant recorded) were further excluded (47.1% [10,485]). To allow for enough events for evaluation, the study sample was restricted to seven stems for which there were at least 300 hemiarthroplasties performed, including four models from DePuy Synthes (Corail®, Summit®, Summit Basic, and Tri-Lock®) and three from Zimmer Biomet (Medial-Lateral [M/L] Taper®, Trabecular Metal®, and Versys® Low Demand Fracture [LD/FX]). The final sample included 5676 cementless hemiarthroplasties: 653 Corail, 402 M/L Taper, 1699 Summit, 1590 Summit Basic, 384 Tri-Lock, 637 Trabecular Metal, and 311 Versys LD/FX. Procedures were performed by 396 surgeons at 35 hospitals. The mean age and BMI for the cohort was 81 years and 24 kg/m 2 , respectively; most were women (66% [3733 of 5676]) and White (79% [4488 of 5676]). Based on standardized mean differences, we controlled for age, race/ethnicity, American Society of Anesthesiologist (ASA) classification, anesthesia technique, operative year, average annual surgeon hemiarthroplasty volume, and operative year across the seven stem groups. Of the 5676 patients, 7% (378 of 5676) were lost to follow-up through membership termination at a median time of 1.6 years, and 56% (3194 of 5676) of the patients died during study follow-up. A multivariable cause-specific Cox proportional hazards regression model was used to evaluate the risk for aseptic revision with adjustment for age, gender, ASA classification, depression, operating surgeon, deficiency anemias, time from admission to surgery, and average annual surgeon hemiarthroplasty volume. A random intercept was included to address effects from hemiarthroplasties performed by the same surgeon. Risk for revision for periprosthetic fracture was also evaluated as a secondary outcome. In the adjusted analysis, the Summit Basic (HR 1.91 [95% confidence interval 1.34 to 2.72]; p < 0.001), the M/L Taper (HR 1.91 [95% CI 1.15 to 3.15]; p = 0.01), and the Versys LD/FX (HR 2.12 [95% CI 1.25 to 3.61]; p = 0.005) had higher aseptic revision risks during follow-up when compared with the Summit. No differences were observed for the Corail (HR 0.57 [95% CI 0.29 to 1.10]; p = 0.09), the Tri-Lock (HR 1.13 [95% CI 0.62 to 2.07]; p = 0.68), or the Trabecular Metal (HR 1.14 [95% CI 0.69 to 1.89]; p = 0.61) compared with the Summit. A higher risk for revision because of periprosthetic fracture was observed with the M/L Taper (HR 2.43 [95% CI 1.29 to 4.58]; p = 0.006) and the Summit Basic (within 3 months of follow-up: HR 1.16 [95% CI 0.60 to 2.25]; p = 0.66; after 3 months of follow-up: HR 2.84 [95% CI 1.36 to 5.94]; p = 0.006) stems when compared with the Summit. In a cohort of 5676 cementless hemiarthroplasties, we found differences in revision risks among different femoral stem brands. Based on our findings, we recommend against utilization of the Zimmer M/L Taper, DePuy Summit Basic, and Zimmer Versys LD/FX in the treatment of displaced geriatric femoral neck fractures with cementless hemiarthroplasty. Future large registry studies are needed to further elucidate differences in aseptic revision risk among higher performing cementless femoral stems. Although cemented fixation remains the recommended approach based on the best available evidence in hemiarthroplasty treatment of hip fractures, our findings may help to mitigate aseptic revision risk should cementless fixation be chosen. Level III, therapeutic study.

Shah I ，Prentice HA ，Okike K ，Navarro RA ，Fasig BH ，Paxton EW ，Grimsrud CD ... -  《-》

Comparison of Two Modern Survival Prediction Tools, SORG-MLA and METSSS, in Patients With Symptomatic Long-bone Metastases Who Underwent Local Treatment With Surgery Followed by Radiotherapy and With Radiotherapy Alone.

Survival estimation for patients with symptomatic skeletal metastases ideally should be made before a type of local treatment has already been determined. Currently available survival prediction tools, however, were generated using data from patients treated either operatively or with local radiation alone, raising concerns about whether they would generalize well to all patients presenting for assessment. The Skeletal Oncology Research Group machine-learning algorithm (SORG-MLA), trained with institution-based data of surgically treated patients, and the Metastases location, Elderly, Tumor primary, Sex, Sickness/comorbidity, and Site of radiotherapy model (METSSS), trained with registry-based data of patients treated with radiotherapy alone, are two of the most recently developed survival prediction models, but they have not been tested on patients whose local treatment strategy is not yet decided. (1) Which of these two survival prediction models performed better in a mixed cohort made up both of patients who received local treatment with surgery followed by radiotherapy and who had radiation alone for symptomatic bone metastases? (2) Which model performed better among patients whose local treatment consisted of only palliative radiotherapy? (3) Are laboratory values used by SORG-MLA, which are not included in METSSS, independently associated with survival after controlling for predictions made by METSSS? Between 2010 and 2018, we provided local treatment for 2113 adult patients with skeletal metastases in the extremities at an urban tertiary referral academic medical center using one of two strategies: (1) surgery followed by postoperative radiotherapy or (2) palliative radiotherapy alone. Every patient's survivorship status was ascertained either by their medical records or the national death registry from the Taiwanese National Health Insurance Administration. After applying a priori designated exclusion criteria, 91% (1920) were analyzed here. Among them, 48% (920) of the patients were female, and the median (IQR) age was 62 years (53 to 70 years). Lung was the most common primary tumor site (41% [782]), and 59% (1128) of patients had other skeletal metastases in addition to the treated lesion(s). In general, the indications for surgery were the presence of a complete pathologic fracture or an impending pathologic fracture, defined as having a Mirels score of ≥ 9, in patients with an American Society of Anesthesiologists (ASA) classification of less than or equal to IV and who were considered fit for surgery. The indications for radiotherapy were relief of pain, local tumor control, prevention of skeletal-related events, and any combination of the above. In all, 84% (1610) of the patients received palliative radiotherapy alone as local treatment for the target lesion(s), and 16% (310) underwent surgery followed by postoperative radiotherapy. Neither METSSS nor SORG-MLA was used at the point of care to aid clinical decision-making during the treatment period. Survival was retrospectively estimated by these two models to test their potential for providing survival probabilities. We first compared SORG to METSSS in the entire population. Then, we repeated the comparison in patients who received local treatment with palliative radiation alone. We assessed model performance by area under the receiver operating characteristic curve (AUROC), calibration analysis, Brier score, and decision curve analysis (DCA). The AUROC measures discrimination, which is the ability to distinguish patients with the event of interest (such as death at a particular time point) from those without. AUROC typically ranges from 0.5 to 1.0, with 0.5 indicating random guessing and 1.0 a perfect prediction, and in general, an AUROC of ≥ 0.7 indicates adequate discrimination for clinical use. Calibration refers to the agreement between the predicted outcomes (in this case, survival probabilities) and the actual outcomes, with a perfect calibration curve having an intercept of 0 and a slope of 1. A positive intercept indicates that the actual survival is generally underestimated by the prediction model, and a negative intercept suggests the opposite (overestimation). When comparing models, an intercept closer to 0 typically indicates better calibration. Calibration can also be summarized as log(O:E), the logarithm scale of the ratio of observed (O) to expected (E) survivors. A log(O:E) > 0 signals an underestimation (the observed survival is greater than the predicted survival); and a log(O:E) < 0 indicates the opposite (the observed survival is lower than the predicted survival). A model with a log(O:E) closer to 0 is generally considered better calibrated. The Brier score is the mean squared difference between the model predictions and the observed outcomes, and it ranges from 0 (best prediction) to 1 (worst prediction). The Brier score captures both discrimination and calibration, and it is considered a measure of overall model performance. In Brier score analysis, the "null model" assigns a predicted probability equal to the prevalence of the outcome and represents a model that adds no new information. A prediction model should achieve a Brier score at least lower than the null-model Brier score to be considered as useful. The DCA was developed as a method to determine whether using a model to inform treatment decisions would do more good than harm. It plots the net benefit of making decisions based on the model's predictions across all possible risk thresholds (or cost-to-benefit ratios) in relation to the two default strategies of treating all or no patients. The care provider can decide on an acceptable risk threshold for the proposed treatment in an individual and assess the corresponding net benefit to determine whether consulting with the model is superior to adopting the default strategies. Finally, we examined whether laboratory data, which were not included in the METSSS model, would have been independently associated with survival after controlling for the METSSS model's predictions by using the multivariable logistic and Cox proportional hazards regression analyses. Between the two models, only SORG-MLA achieved adequate discrimination (an AUROC of > 0.7) in the entire cohort (of patients treated operatively or with radiation alone) and in the subgroup of patients treated with palliative radiotherapy alone. SORG-MLA outperformed METSSS by a wide margin on discrimination, calibration, and Brier score analyses in not only the entire cohort but also the subgroup of patients whose local treatment consisted of radiotherapy alone. In both the entire cohort and the subgroup, DCA demonstrated that SORG-MLA provided more net benefit compared with the two default strategies (of treating all or no patients) and compared with METSSS when risk thresholds ranged from 0.2 to 0.9 at both 90 days and 1 year, indicating that using SORG-MLA as a decision-making aid was beneficial when a patient's individualized risk threshold for opting for treatment was 0.2 to 0.9. Higher albumin, lower alkaline phosphatase, lower calcium, higher hemoglobin, lower international normalized ratio, higher lymphocytes, lower neutrophils, lower neutrophil-to-lymphocyte ratio, lower platelet-to-lymphocyte ratio, higher sodium, and lower white blood cells were independently associated with better 1-year and overall survival after adjusting for the predictions made by METSSS. Based on these discoveries, clinicians might choose to consult SORG-MLA instead of METSSS for survival estimation in patients with long-bone metastases presenting for evaluation of local treatment. Basing a treatment decision on the predictions of SORG-MLA could be beneficial when a patient's individualized risk threshold for opting to undergo a particular treatment strategy ranged from 0.2 to 0.9. Future studies might investigate relevant laboratory items when constructing or refining a survival estimation model because these data demonstrated prognostic value independent of the predictions of the METSSS model, and future studies might also seek to keep these models up to date using data from diverse, contemporary patients undergoing both modern operative and nonoperative treatments. Level III, diagnostic study.

Lee CC ，Chen CW ，Yen HK ，Lin YP ，Lai CY ，Wang JL ，Groot OQ ，Janssen SJ ，Schwab JH ，Hsu FM ，Lin WH ... -  《-》

What Are the Complications, Reconstruction Survival, and Functional Outcomes of Modular Prosthesis and Allograft-prosthesis Composite for Proximal Femur Reconstruction in Children With Primary Bone Tumors?

Proximal femur reconstruction after bone tumor resection in children is a demanding surgery for orthopaedic oncologists because of the small bone size and possible limb-length discrepancy at the end of skeletal growth owing to physis loss. The most commonly used reconstruction types used for the proximal femur are modular prostheses and allograft-prosthesis composites. To our knowledge, there are no previous studies comparing the outcomes after modular prosthesis and allograft-prosthesis composite reconstruction of the proximal femur in children with primary bone tumors. (1) What was the cumulative incidence of reoperation for any reason after allograft-prosthesis composite and modular prosthesis reconstructions of the proximal femur in children with primary bone tumors? (2) What was the cumulative incidence of reconstruction removal or revision arthroplasty in those two treatment groups? (3) What complications occurred in those two treatment groups that were managed without further surgery or with surgery without reconstruction removal? Between 2000 and 2021, 54 children with primary bone tumors underwent resection and reconstruction of the proximal femur at a single institution. During that time, allograft-prosthesis composite reconstruction was used in very young children, in whom we prioritize bone stock preservation for future surgeries, and children with good response to chemotherapy, while modular prosthesis reconstruction was used in older children and children with metastatic disease at presentation and poor response to chemotherapy. We excluded three children in whom limb salvage was not possible and 11 children who underwent either reconstruction with free vascularized fibular graft and massive bone allograft (n = 3), an expandable prosthesis (n = 3), a massive bone allograft reconstruction (n = 2), a rotationplasty (n = 1), standard (nonmodular) prosthesis (n = 1), or revision of preexisting reconstruction (n = 1). Further, we excluded two children who were not treated surgically, three children with no medical or imaging records, and three children with no follow-up. All the remaining 32 children with reconstruction of the proximal femur (12 children treated with modular prosthesis and 20 children treated with allograft-prosthesis composite reconstruction) were accounted for at a minimum follow-up time of 2 years. Children in the allograft-prosthesis group were younger at the time of diagnosis than those in the modular prosthesis group (median 8 years [range 1 to 16 years] versus 15 years [range 9 to 17 years]; p = 0.001]), and the follow-up in the allograft-prosthesis composite group was longer (median 5 years [range 1 to 23 years] versus 3 years [range 1 to 15 years]; p = 0.37). Reconstruction with hemiarthroplasty was performed in 19 of 20 children in the allograft-prosthesis composite group and in 9 of 12 children in the modular prosthesis group. A bipolar head was used in 16 of 19 children, and a femoral ceramic head without acetabular cup was used in 3 of 19 children in the allograft-prosthesis composite reconstruction group. All 9 children in the modular prosthesis group were reconstructed with a bipolar hemiarthroplasty. Reconstruction with total arthroplasty was performed in one child in the allograft-prosthesis composite group and in three children in the modular prosthesis group. For both groups, we calculated the cumulative incidence of reoperation for any reason and the cumulative incidence of reconstruction removal or revision arthroplasty; we also reported qualitative descriptions of serious complications treated nonoperatively in both groups. The cumulative incidence of any reoperation at 10 years did not differ between the groups with the numbers available (36% [95% confidence interval 15% to 58%] in the allograft-prosthesis composite group versus 28% [95% CI 5% to 58%] in the modular proximal femoral replacement group). The cumulative incidence of reconstruction removal or revision arthroplasty at 10 years likewise did not differ between the groups with the numbers available (10% [95% CI 2% to 28%] versus 12% [95% CI 0% to 45%], respectively). In the allograft-prosthesis composite group (20 children), hip instability (n = 3), nonunion (n = 2), fracture of the greater trochanter (n = 1), screw loosening (n = 1), limb-length discrepancy (n = 1), and coxalgia due to acetabular wear (n = 1) were treated surgically without reconstruction removal. Complications treated without surgery included resorption of the allograft at the trochanteric region (n = 4), fracture of the greater trochanter (n = 4), limb-length discrepancy (n = 6), and coxalgia due to acetabular wear (n = 2). In the modular prosthesis group (12 children), hip instability (n = 1), coxalgia due to acetabular wear (n = 1), and limb-length discrepancy (n = 1) were treated surgically without reconstruction removal. Complications treated without surgery included hip instability (n = 2), stress shielding (n = 6), infection (n = 1), sciatic nerve palsy (n = 1), and limb-length discrepancy (n = 3). Although the two groups of children were not directly comparable due to differences in age and clinical characteristics, both modular prosthesis and allograft-prosthesis composite reconstructions of the proximal femur after bone tumor resection appear to be reasonable options with similar revision-free survival and complications. Therefore, the type of reconstruction following proximal resection in children with bone sarcoma should be chosen taking into consideration factors such as patient age, bone size, implant availability, technical expertise, and the surgeon's preference. Although children treated with expandable prostheses were not included in this study, such prostheses may be useful in bridging the surgical defect while correcting residual limb-length discrepancies even though they face limitations such as small intramedullary diameter, short residual bone segments, as well as stress shielding, loosening, and breakage. Level III, therapeutic study.

Atherley O'Meally A ，Rizzi G ，Cosentino M ，Aiba H ，Aso A ，Solou K ，Campanacci L ，Zuccheri F ，Bordini B ，Donati DM ，Errani C ... -  《-》

What Are the Functional, Radiographic, and Survivorship Outcomes of a Modified Cup-cage Technique for Pelvic Discontinuity?

Pelvic discontinuity (PD) presents a complex challenge in revision hip arthroplasty. The traditional cup-cage construct, which involves a screw-secured porous metal cup and an overlying antiprotrusio cage, has shown promising mid- to long-term results. However, there is limited information on the outcomes of modifications to the original technique. Our study aims to evaluate a modified technique in which the cup position is determined by the placement of the overlying cage, allowing for adjustments to achieve optimal orientation. Among patients treated for PD with a cup-cage construct in which the cup position was dictated by the position of the cage: (1) What are Harris hip scores achieved at a minimum of 2 years of follow-up? (2) What is the Kaplan-Meier survivorship free from aseptic loosening or component migration? (3) What is the Kaplan-Meier survivorship free from revision for any reason? (4) What surgical complications are associated with the procedure? Between October 2013 and January 2022, we performed 805 acetabular revisions. Among these, 33 patients with PD confirmed intraoperatively were considered potentially eligible for a cup-cage construct; no other method of surgical management was used. We performed 64% (21 of 33) of these procedures from October 2013 to January 2018, with 6% (2 of 33) of patients lost to follow-up before the minimum study follow-up of 2 years; these 19 patients were monitored over a period ranging from 70 to 115 months. A further 12 patients underwent this procedure from January 2018 to January 2022, with one lost to follow-up before the minimum study follow-up of 2 years; the other patients met the minimum 2-year follow-up requirement. The remaining 30 patients with data analyzed here (10 men, 20 women) had a mean ± SD age of 61 ± 12 years and a median BMI of 29 kg/m 2 (range 20 to 33 kg/m 2 ) at the time of revision surgery. Twenty-one patients underwent revision due to aseptic loosening, and nine due to periprosthetic joint infection (PJI). The causes of PD in our patients were as follows: cup aseptic loosening without significant osteolysis in 20% (6 of 30), where the loose cup caused erosion of the host bone, leading to PD; PJI in 30% (9 of 30); intraoperative iatrogenic PD in 3% (1 of 30); and osteolysis in 47% (14 of 30), which also resulted in aseptic loosening. The median follow-up time was 79 months (range 25 to 115 months). The Harris hip score was used to evaluate clinical outcomes, with preoperative values compared with the most recent follow-up. Radiographs were reviewed by two experienced surgeons at each follow-up visit to assess component loosening (defined as migration > 5 mm or the presence of circumferential radiolucent lines) or clear migration. PD was considered healed if bridging callus or trabecular bone was visible across the site of the discontinuity. Complications were assessed through a comprehensive review of electronic medical records. Kaplan-Meier analysis was used to estimate implant survivorship and radiographic loosening, with aseptic loosening or component migration as the endpoint, as well as survivorship free from any reoperation. The Harris hip score improved from a median of 39 (range 30 to 66) preoperatively to a median of 76 (range 30 to 90) postoperatively (median difference 33 [range 2 to 48]; p < 0.01). Within the limitations of two-dimensional (2D) radiographic imaging, successful bone graft integration and the healing of PD were noted in 83% (25 of 30) of patients. Kaplan-Meier survivorship free from radiographic signs of aseptic loosening or component migration was 100% (95% CI 100% to 100%) at 115 months. When any revision related to the acetabular component was considered the endpoint, survivorship free from acetabular component revision at 115 months after revision surgery was 100% (95% CI 100% to 100%). When the need for any reoperation was considered the endpoint, survivorship free from needing reoperation at 115 months after revision surgery was 85% for all patients (95% CI 73% to 100%). When including only patients with a follow-up time of > 4 years (20 of 30), survivorship free from needing reoperation at 115 months after revision surgery was 90% (95% CI 78% to 100%). Postoperative complications during the follow-up period included one early dislocation on the fifth day after surgery, treated with closed reduction and 6 weeks of abduction bracing. One femoral stem loosening occurred at 56 months postoperatively, although the acetabular component remained securely fixed; this patient declined revision surgery. One patient experienced a dislocation 5 months after surgery but refused treatment and opted for prolonged bed rest. Additionally, one patient underwent a debridement, antibiotics, and implant retention procedure 1 week after the revision surgery and subsequently showed no signs of infection at the latest follow-up, 38 months postoperatively. Our study highlights the effectiveness of a modified cup-cage technique in complex hip revisions, showing promising results in terms of construct survivorship and low complication rates. Surgeons could consider delaying screw fixation until after positioning the cage within the porous cup to allow for optimal adjustment and using metal augments for severe bone defects to achieve better alignment. Surgeon experience with the cup-cage technique is crucial for achieving optimal outcomes. Future studies should focus on long-term follow-up visits to assess the durability and effectiveness of these modifications and explore the comparative effectiveness versus other methods, such as custom triflange components and jumbo cups with distraction. Level III, therapeutic study.

Mu W ，Xu B ，Wahafu T ，Wang F ，Guo W ，Zou C ，Cao L ... -  《-》