AbstractIntroductionThe humerus is a common site of metastases and primary tumors. For some patients with a segmental defect and/or diaphyseal cortical destruction a cemented intercalary device may provide a more reliable construct, however data on their use is limited.MethodsWe reviewed 43 (28 male and 15 female) patients treated with an intercalary humeral spacer at a single tertiary referral center between 1989 and 2022. Humeral lesions were most commonly secondary to metastatic disease (n = 29, 68%), with 25 (58%) patients presenting with a pathologic fracture. Mean age and body mass index were 66 years and 27.9 kg/m2. First generation taper joint device were used in 22 patients and second‐generation lap device in 21 patients.ResultsFollowing reconstruction the 2‐year overall survival was 30%. Mechanical complications occurred in 11 patients, most commonly aseptic loosening (n = 6, 14%). With death as a competing risk, the cumulative incidence of mechanical failure was 28% at 2‐years postoperative. Following the procedure, mean Musculoskeletal Tumor Society scores was 70% and mean shoulder elevation was 87°.ConclusionReconstruction of the humeral diaphysis with an intercalary endoprosthesis provides restoration of function of the upper extremity, however, is associated with one in four patients having mechanical failure.
AbstractPurposeExtraskeletal Ewing sarcoma (EES), is a rare soft tissue sarcoma. Treatment for EES commonly involves chemotherapy and surgical resection (ST) or less commonly combined chemotherapy, surgery, and radiotherapy (ST + RT). The purpose of the current study was to evaluate our institutional experience treating EES.MethodsWe reviewed 36 (18 males:18 females) patients (mean age 30 years) with a nonretroperitoneal/visceral EES treated with either ST (n = 24, 67%) or ST + RT (n = 12, 33%). All patients were treated with chemotherapy, most commonly vincristine, doxorubicin, cyclophosphamide/ifosfamide and etoposide (VDC/IE, n = 23, 66%) Radiotherapy was mostly delivered preoperatively (n = 9). The mean follow‐up was 8 years.ResultsThe 10‐year disease specific survival for patients was 78%, with no difference in the survival between patients in the ST versus the ST + RT groups (83% vs. 71%, p = 0.86). There was no difference in the 10‐year local recurrence (91% vs. 100%, p = 0.29) or metastatic free survival (87% vs. 75%, p = 0.45) between the ST and ST + RT groups.ConclusionThe results of the current study highlight the ability to achieve excellent local control with chemotherapy and surgery for EES. We recommend for multidisciplinary management of patients with EES, including chemotherapy and surgery, with use of radiotherapy if there is concern for a potentially close margin of resection.
Lack of radiosensitivity predicts poor disease specific survival in myxoid liposarcoma
AbstractBackgroundCompared to other sarcomas, myxoid liposarcoma (ML) is known to be radiosensitive, with improved oncologic outcomes. Although these tumors “shrink” following radiotherapy, there is a paucity of data examining the degree of radiosensitivity and oncologic outcome. The purpose of the study was to evaluate pre‐ and postradiotherapy tumor volume to determine if size reduction impacts outcome.MethodsWe reviewed 62 patients with ML undergoing surgical resection combined with preoperative radiotherapy, with pre‐ and postradiotherapy MRI. This included 34 (55%) males, with a mean age of 47 ± 14 years. All tumors were deep to the fascia, and 12 (19%) patients had tumors with a >5% round‐cell component.ResultsThe mean volume reduction was 54% ± 29%. Compared to patients with >25% volume reduction, patients with reduction ≤25% had worse 10‐year disease specific survival (86% vs. 37%, p < 0.01), in addition to an increased risk of metastatic disease (HR 4.63, p < 0.01) and death due to disease (HR 4.52, p < 0.01).ConclusionLack of volume reduction is a risk factor for metastatic disease and subsequent death due to disease in patients with extremity ML treated with combined preoperative radiotherapy and surgery. This data could be used to stratify patients for adjuvant therapies and follow‐up intervals.
Comparison of all‐polyethylene and metal‐backed modular tibial components in endoprosthetic reconstruction of the distal femur
AbstractIntroductionAll‐polyethylene (AP) tibial components have demonstrated equivalent or improved long‐term survivorship and reduced cost compared with metal‐backed (MB) components in primary total knee arthroplasty; however, there is a lack of data comparing these outcomes in the setting of an oncologic endoprosthetic reconstruction.MethodsA total of 115 (88 AP:27 MB) patients undergoing cemented distal femur endoprosthetic reconstruction following oncologic resection were reviewed. Mean age was 40 years and 51% were females. Cumulative incidences of all‐cause revision, tibial component revision, reoperation, and infection were calculated utilizing a competing risk analysis with death as the competitor. Mean follow‐up was 14 years.ResultsThe 10‐year cumulative incidence of all‐cause revision was 19.9% in the AP group and 16.3% in the MB group (hazard ratio [HR] = 0.93, p = 0.88). The cumulative incidence of tibial component revision was significantly lower in AP compared with MB at 10 years (1.1% vs. 12.5%, HR = 0.18, p = 0.03). There was no difference in infection‐free survival when comparing the two groups (p = 0.72).ConclusionsReconstruction utilizing an MB or AP tibia component resulted in equivalent overall outcome; however, the tibial component in the AP group was less likely to be revised. AP tibial component should be considered for all primary oncologic reconstructions in the distal femur.Level of EvidenceLevel III Therapeutic.
Hitting the Target: Natural History of the Hip Based on Achieving an Acetabular Safe Zone Following Periacetabular Osteotomy
Background: Periacetabular osteotomy (PAO) remains the gold-standard treatment for acetabular dysplasia in skeletally mature patients with preserved cartilage. The purpose of this multicenter cohort study was to delineate the long-term radiographic natural history of the dysplastic hip following PAO based on the final position of the acetabular fragment. Methods: We evaluated patients who underwent PAO performed by 4 hip preservation surgeons to treat acetabular dysplasia with or without concomitant retroversion from 1996 to 2012 at 3 academic institutions. There were 288 patients with a mean clinical and radiographic follow-up of 9 years (range, 5 to 21 years). Postoperative radiographs made at the first clinical visit were used to determine if the acetabular fragment fell into a safe zone according to the absence of retroversion, a lateral center-edge angle (LCEA) of 25° to 40°, an anterior center-edge angle (ACEA) of 25° to 40°, and a Tönnis angle of 0° to 10°. Every available subsequent radiograph was assessed for degenerative changes by the Tönnis classification (grades 0 to 3). The time to progression was analyzed using Cox proportional hazards regression and multistate modeling. Results: Only the absence of retroversion was independently associated with a decreased risk of progressing at least 1 Tönnis grade during follow-up: hazard ratio (HR), 0.60 (95% confidence interval [CI], 0.38 to 0.94; p = 0.025). Achieving the ACEA safe zone yielded the greatest time increase for remaining in Tönnis grade 0 or 1 (43 years for having an ACEA in the safe zone compared with 28 years for not having an ACEA in the safe zone), followed by the absence of retroversion (34 years for the absence of retroversion compared with 24 years for the presence of retroversion). However, attaining the Tönnis angle or LCEA safe zones did not delay progression. The achievement of additional safe zones generally increased the length of time that patients spent in Tönnis grade 0 or 1: 25 years for 0 safe zones, 36 years for 1 safe zone, 29 years for 2 safe zones, 37 years for 3 safe zones, and 44 years for 4 safe zones. Conclusions: This study demonstrates the importance of achieving appropriate acetabular reorientation to enhance the longevity of the native hip following PAO. Although the LCEA and the Tönnis angle are the most common metrics used to assess appropriate acetabular correction, this study shows that adequately addressing retroversion and the ACEA has a greater impact on improving the natural history. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Natural History of the Dysplastic Hip Following Modern Periacetabular Osteotomy
Background: Periacetabular osteotomy (PAO) is the most common treatment for symptomatic acetabular dysplasia, or developmental dysplasia of the hip (DDH), in skeletally mature patients. The purpose of this multicenter cohort study was to delineate the long-term radiographic natural history of the dysplastic hip following PAO. Methods: We evaluated all patients undergoing PAO from 1996 to 2012 at 3 academic institutions in the United States. Inclusion criteria were PAO for DDH with a minimum 5-year radiographic follow-up. Exclusion criteria were PAO for isolated acetabular retroversion, neurogenic dysplasia, Legg-Calvé-Perthes disease, and prior hip surgery including osteotomies and arthroscopy. There were 288 patients, 83% of whom were women; the mean age and body mass index (BMI) were 29 years and 25 kg/m 2 , respectively. The mean clinical and radiographic follow-up was 9.2 years (range, 5.0 to 21.1 years). Every preoperative and postoperative hip radiograph was assessed to determine the degree of osteoarthritis according to the Tönnis classification. Survivorship was analyzed by multistate modeling, enabling assessment of progression through the Tönnis grades rather than just individual transitions as with Kaplan-Meier techniques. Results: At the time of final follow-up, 144 patients (50%) had progressed at least 1 Tönnis grade, with 42 patients (14.6%) undergoing total hip arthroplasty. The mean number of years spent in each Tönnis grade following PAO was 19 for Tönnis grade 1, 8 for Tönnis grade 2, and 4 for Tönnis grade 3. The probability of progression to total hip arthroplasty increased significantly on the basis of a higher initial Tönnis grade (p < 0.001). The most marked difference occurred between Tönnis grade 0 or 1 and Tönnis grade 2; for Tönnis grade 1, the probability of progression to total hip arthroplasty at 5 and 10 years was 2% and 11%, respectively, compared with 23% and 53%, respectively, for Tönnis grade 2. Conclusions: PAO effectively alters the natural history of DDH. Precise radiographic progression based on the Tönnis grade can now be used to ascribe prognosis for the native hip. Importantly, this investigation demonstrates a stark increase in progression to total hip arthroplasty within 10 years of PAO for patients with preoperative Tönnis grade-2 osteoarthritis compared with those with Tönnis grade-0 or 1 osteoarthritis. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
The Recurrent Instability of the Patella Score: A Statistically Based Model for Prediction of Long‐Term Recurrence Risk After First‐Time Dislocation
Purpose To describe the clinical history of a series of primary, lateral patellar dislocations and determine long‐term predictors of recurrent instability while accounting for patients undergoing early operative management. Methods A large geographic database of more than 500,000 patients was used to identify patients who sustained a first‐time lateral patellar dislocation between 1990 and 2010. Charts were individually reviewed to document demographics, radiographic measures including tibial tubercle to trochlear groove distance (TT‐TG) and patellar length (PL), recurrent episodes of instability, and patellar stabilization surgery. A risk score that accounted for early surgical management was calculated using Fine and Gray competing risk regression, and its ability to stratify patients was examined using cumulative incidence curves. Results Eighty‐one patients (mean age 19.9 ± 9.4 years, 38 male, 43 female) were identified and followed for a mean of 10.1 years (range 4.1‐20.2). Thirty‐eight patients (46.9%) experienced an episode of recurrent instability and 30 (37.0%) underwent patellar stabilization surgery, including 7 who did so before recurrent dislocation. A multivariate, statistically derived scoring system, the Recurrent Instability of the Patella Score (RIP Score), that employed age, skeletal maturity, trochlear dysplasia, and TT‐TG/PL ratio to predict recurrent instability while accounting for patients managed surgically, was generated. The resulting RIP score stratified patients into low‐, intermediate‐, and high‐risk categories, with 0.0%, 30.6%, and 79.2% 10‐year recurrent instability rates, respectively ( P = .000004), and an area under the curve of 0.875 ( P = .00002). Conclusions Patients who sustain a first‐time, lateral patellar dislocation can be readily classified into low‐, intermediate‐, and high‐risk categories employing the RIP score based on age, skeletal maturity, trochlear dysplasia, and TT‐TG/PL ratio. This long‐term risk stratification holds significant potential clinical utility for determination of patients who are at high risk for recurrent instability after primary patellar dislocation. Level of Evidence Level III, retrospective comparative study.
Renal fossa recurrence after nephrectomy for renal cell carcinoma: prognostic features and oncological outcomes
Objectives To describe the clinicopathological features associated with increased risk of renal fossa recurrence ( RFR ) after radical nephrectomy ( RN ) and to describe the prognostic features associated with cancer‐specific survival ( CSS ) among patients with RFR treated with primary locally directed therapy, systemically directed therapy or expectant management. Patients and Methods The records of 2 502 patients treated with RN for unilateral, sporadic, localized renal cell carcinoma ( RCC ) between 1970 and 2006 were reviewed. CSS after RFR was estimated using the Kaplan–Meier method. Associations with the development of RFR and CSS after RFR were evaluated using Cox proportional hazards regression models. Results A total of 33 (1.3%) patients developed isolated RFR ( iRFR ) and 30 (1.2%) patients developed RFR in the setting of synchronous metastases after RN (study cohort, N = 63). The median follow‐up for the series was 9.0 years after RN and 6.0 years after RFR diagnosis. On multivariable analysis, advanced pathological stage ( pT 2: hazard ratio [ HR ] 4.36, P = 0.004; pT 3/4: HR 4.39, P = 0.003) and coagulative necrosis ( HR 2.71, P = 0.006) were independently associated with increased risk of iRFR . The median time to recurrence was 1.5 years after RN among the 33 patients with iRFR , and 1.4 years among all patients. Overall, the median CSS was 2.5 years after diagnosis of iRFR , 1.3 years after RFR in the setting of synchronous metastases, and 2.2 years overall. After primary locally directed therapy (surgery, ablation or radiation), systemic therapy or expectant management, the 3‐year CSS rates among patients with iRFR were 63%, 50% and 13% ( P = 0.001) and were 64%, 50% and 28% ( P = 0.006) among all patients, respectively. On multivariable analysis, when compared with observation, locally directed therapies were associated with a significantly decreased risk of death from RCC ( HR 0.26, P < 0.001). Conclusions Renal fossa recurrence is a rare event after RN for RCC and portends a poor prognosis, even in the absence of synchronous metastases. Development of iRFR is associated with advanced stage and aggressive tumour biology. Patients who underwent primary locally directed therapy had superior CSS compared with those treated with expectant management, supporting the use of aggressive local treatment in carefully selected patients with RFR . Future research is needed to determine the optimum role and sequencing of combined therapy in patients with this rare entity.
Individualizing the Tibial Tubercle–Trochlear Groove Distance
Background: Patients with patellar instability and a tibial tubercle–trochlear groove (TT-TG) distance ≥20 mm may be candidates for distal tubercle realignment surgery. Although this variable has proven valuable in predicting recurrent dislocations, it is not individualized to patient size, bony structure, or patellofemoral mechanics. Purpose: To develop a patellar instability ratio (PIR) that predicts the risk of recurrent instability based on the TT-TG distance to patient-specific anatomy. Study Design: Cohort study; Level of evidence, 3. Methods: On magnetic resonance imaging scans of 59 knees with patellar instability, the TT-TG distance, tibial tubercle–posterior cruciate ligament (TT-PCL) distance, sagittal patellar length (PL), sagittal trochlear length (TL), axial patellar width (PW), and axial trochlear width (TW) were calculated by 2 observers in a blinded and randomized fashion. Patients were divided into 2 groups: those with a single dislocation and those with multiple (≥2) dislocations. The ability of the TT-TG and TT-PCL distances as well as the 8 different ratios to predict recurrent instability was assessed by calculating odds ratios (ORs), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for each measure. Results: Twelve knees (20%) experienced a single dislocation, while 47 (80%) sustained multiple dislocations. A TT-TG distance ≥20 mm was predictive of recurrent instability, with a sensitivity, specificity, and PPV of 21%, 100%, and 100%, respectively. The OR for TT-TG ≥20 mm was 5.38 ( P = .29), while the highest ORs for recurrent instability were noted for a TT-TG/PW ≥0.4 (OR, 7.37; P = .02) and a TT-TG/TW ≥0.5 (OR, 8.88; P = .04). The sensitivity, specificity, and PPV of a TT-TG/PW ≥0.4 were 62%, 83%, and 94%, respectively, while those of a TT-TG/TW ≥0.5 were 45%, 92%, and 95%, respectively. Conclusion: Two novel PIRs (TT-TG/TW and TT-TG/PW) were identified and found to more effectively predict recurrent instability than the TT-TG distance alone. Each ratio takes into account patient-specific anatomy and can be measured in an accurate and reliable fashion by clinicians. These PIRs are a step toward overcoming some of the limitations of using the TT-TG distance in isolation. Further investigation into the clinical applications and utility of the TT-TG/TW is warranted.
Objectives: Patients with patellar instability and tibial tubercle to trochlear groove (TT-TG) distances ≥ 20 mm are often considered to have pathologic lateralization of the tibial tubercle (TT) relative to the femoral trochlea and may be candidates for TT realignment surgery. Although this variable has proven valuable in predicting risk of recurrent dislocations, the measure is limited in that it is not individualized to the patient and does not consider patient size, bony morphology, or patellofemoral mechanics. The purpose of this study was to develop a Patellar Instability Ratio (PIR) that predicts the risk of recurrent instability based on the TT-TG distance relative to patient specific anatomy. Methods: Fifty-nine patients with a clinical diagnosis of patellar instability were included in the study. A number of measures were calculated on MRI by two observers (one staff orthopedic surgeon and one senior resident) in a blinded and randomized fashion. Variables analyzed included: TT-TG, tibial tubercle to posterior cruciate ligament distance (TT-PCL), sagittal patellar length (PL), sagittal trochlear length (TL), axial patellar width (PW), axial trochlear width (TW), sagittal patellofemoral engagement (SPE; SPE=TL/PL) and axial patellofemoral engagement (APE; APE=PW/TW). Patients were divided into two groups: those with ≤ 1 dislocation and those with ≥ 2 dislocations. Using these groups, the ability of TT-TG, TT-PCL, and 12 different ratios with cut-off values to predict recurrent instability was assessed by calculating odds ratios (OR), C-statistics, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each of the ratios. P values < 0.05 were considered significant. Results: Mean follow up was 6.6 years. Twelve patients (20%) did not experience recurrent instability while 47 (80%) sustained two or more dislocations during the study period. Pathologic TT-TG (≥ 20 mm) was predictive of recurrent instability with an OR of 5.38 (p=0.29). The highest OR's for recurrent instability were noted for TT-TG/PW ≥ 0.40 (OR > 7.37, p=0.02) and TT-TG/TW ≥ 0.5 (OR 8.88, p=0.04)(Table 1). PW was defined as the largest medial to lateral width of the articular surface of the patella. TW is defined as the largest articular width of the trochlea that is articulating with the patella and can be conceptualized as the “jump distance” that must be overcome for the patella to dislocate. The sensitivity and specificity of TT-TG/PW ratio ≥ 0.40 was 61% and 83% and that of TT-TG/TW ≥ 0.50 was 59% and 92%, respectively. PPV for TT-TG/PW ≥ 0.40 was 94% while that of TT-TG/TW ≥ 0.49 was 97%. Conclusion: Two distinct PIR (TT-TG/PW and TT-TG/TW) have been identified that predict recurrent patellar instability more accurately than TT-TG ≥ 20 mm with PPV's ≥ 94% and OR's > 7 for both measures. These ratios take into consideration the TT-TG relative to patient specific size and anatomy. Further research is needed to determine if patients with increased PIR benefit from TT osteotomy.