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Aileen M Davis

Publications and source records attributed to Aileen M Davis.

35 records · Page 2Linked to original sources
PubMed2005

Uncemented tumor endoprostheses at the knee: root causes of failure.

UNLABELLED: Although cemented tumor endoprostheses are the most commonly used method for reconstruction of the distal femur or proximal tibia after resection of primary bone tumors, aseptic loosening remains a common complication. Uncemented tumor prostheses may minimize this problem. We investigated the root causes of prosthetic failure for 99 patients with a fixed-hinge, bone-ingrowth Kotz Modular Femur and Tibia Resection System endoprosthesis and compared complications that led to implant failure with results in the literature. Of the 74 distal femoral implants and 25 proximal tibial implants, 25 patients had complications that resulted in prosthetic failure (removal of the prosthesis) at a median of 24.1 (range, 0.8-72.6) months. Failure was caused by prosthesis (n = 18) or oncologic-related (n = 7) complications. However, limb-salvage was possible for 87 of 99 patients. Smaller stem size in the distal femur and longer bone resection length in the proximal tibia were significantly associated with increased risk of prosthetic failure by multivariate analysis. The risk of stem fracture (6 of 99 patients) and infection (10 of 99 patients) was higher than other reports, but aseptic loosening (2 of 99 patients) was uncommon. These results suggest that although the bone-ingrowth surface of this prosthesis leads to a very low aseptic loosening rate, the higher risk of stem fracture and infection must be addressed in future implant designs. LEVEL OF EVIDENCE: Therapeutic study, level IV-1 (case series).

Adult↗
PubMed2004

The indications for and the prognostic significance of amputation as the primary surgical procedure for localized soft tissue sarcoma of the extremity.

BACKGROUND: The indications for primary amputation of a localized soft tissue sarcoma (STS) of the extremity are not well defined in the literature. However, it has been suggested that patients who require an amputation to treat an STS are at increased risk for developing metastases. We categorized the main indications for primary amputation in our patient population and compared their oncological outcome with the outcome of patients who underwent limb-sparing surgery. METHODS: 413 consecutive patients treated surgically at a single center for primary, nonmetastatic, deep, intermediate-, or high-grade STS of the extremity were reviewed. Indications for primary amputation were identified. Demographics and outcomes were compared between the amputation and limb-salvage groups. Multivariate Cox model analysis was used to identify independent risk factors for systemic relapse. RESULTS: Twenty-five (6%) of 413 patients with STS underwent primary amputation: they were older (P = .05), had larger tumors (P = .001), and had a significantly greater risk of developing metastatic disease than patients who underwent limb-sparing procedures (P = .008). However, multivariate analysis demonstrated that the only independent predictors of systemic relapse were tumor size (P = .0001) and tumor grade (P = .0001). Primary amputation was not an independent risk factor for metastatic disease. CONCLUSIONS: The decision to perform a primary amputation for an STS of the extremity is based on the location and local extent of the tumor, and the expected function of the extremity after tumor resection. The higher risk of metastases for patients who require primary amputation is accounted for by independent risk factors associated with their tumors--predominantly large tumor size.

Adolescent↗
PubMed2004

Evaluation of clinical utility of BTC-2000 for measuring soft tissue fibrosis.

PURPOSE: To evaluate whether mechanical tissue parameters, specifically laxity (in millimeters) and energy absorption (millimeters of mercury multiplied by millimeters) as measured by the BTC-2000, could discriminate levels of fibrosis severity among patients treated for extremity soft tissue sarcoma by surgery alone; preoperative radiotherapy (RT) and surgery; and surgery followed by postoperative RT. METHODS AND MATERIALS: A total of 41 patients were treated for extremity soft tissue sarcoma by surgery alone (n = 11); preoperative RT (50 Gy in 2-Gy daily fractions) and surgery (n = 15); and surgery followed by postoperative RT (66 Gy in 2-Gy daily fractions; n = 15). Serial fibrosis measurements were evaluated at equal intervals from the midpoint of the surgical incision along the length of the incision. On the basis of the average of these measurements, differences among the three groups were analyzed using analysis of variance. RESULTS: Pair-wise statistically significant differences were found among the three treatment groups for both laxity and energy absorption as determined by the average of all measurements. The treatment difference remained statistically significant even after adjusting for differences based on the untreated contralateral limb and anatomic site (p <0.001 and p = 0.002 for laxity and energy absorption, respectively). CONCLUSION: The biomechanical tissue parameters of laxity and energy absorption discriminated fibrosis severity in patients treated with different RT doses. The BTC-2000 may provide a useful quantitative measure of soft tissue fibrosis.

Combined Modality Therapy↗
PubMed2004

Rehabilitation and quality-of-life issues in patients with extremity soft tissue sarcoma.

The current standard of care for soft tissue sarcoma (STS) is limb salvage surgery and adjuvant radiotherapy, with long-term survival rates of approximately 70%. However, the extensive surgical resection and subsequent reconstruction result in 50% of survivors living with chronic disability. Rehabilitation aims to optimize functional independence and quality of life, and is routinely offered to patients undergoing surgical treatment for STS. Unfortunately, there is a dearth of research related to rehabilitation in this area. We propose a model for assessing disability, for designing treatment interventions and for evaluating rehabilitative outcomes in STS. The World Health Organization's (WHO) international classification of functioning, disability, and health (ICF) is divided into three domains: 1) impairments (related to body structure and function), 2) activity limitations (related to usual self-care activities/activities of daily living), and 3) participation restrictions (related to social roles). A literature review of STS rehabilitation reveals that most studies have focused on disability assessment, with few papers describing or evaluating rehabilitation interventions commonly employed in STS. Clinicians are forced to extrapolate findings from other patient populations in order to evaluate the effectiveness of specific rehabilitation strategies (ie, those used for particular sequelae of STS, such as lymphedema or impaired exercise tolerance). There is strongest support for complex decongestive physiotherapy (targeting lymphedema) and aerobic exercise interventions (aimed at alleviating cancer-related fatigue and psychosocial sequelae). The most poorly researched topic is rehabilitation for genitourinary disability (both incontinence and sexual dysfunction). Most studies related to oncologic rehabilitation are restricted to the impairment level (eg, affecting range of motion, muscle strength) of the ICF, with only a small minority addressing activity limitations (eg, affecting activities of daily living) experienced by patients. A consideration of participation restrictions (eg, fulfillment of vocational roles) is almost wholly absent from the literature. Yet social role reintegration is of fundamental importance to patients. Further research is required in these two domains. The ICF provides a comprehensive framework for future research into rehabilitation interventions for STS.

Extremities↗
PubMed2004

Clonogenic survival and cytokinesis-blocked binucleation of skin fibroblasts and normal tissue complications in soft tissue sarcoma patients treated with preoperative radiotherapy.

BACKGROUND AND PURPOSE: To evaluate the clonogenic and cytokinesis-blocked assays in skin fibroblast cultures for their utility as tools for predicting normal tissue responses in soft tissue sarcoma (STS) patients treated with preoperative radiotherapy. PATIENTS AND METHODS: Dermal fibroblast strains were established from skin biopsies of 26 STS patients who received preoperative radiotherapy. Cultures were subjected to the colony forming and cytokinesis-blocked assays after low (approximately 0.02 Gy/min) dose-rate 60Co -irradiation. Fibroblast radiosensitivity was expressed as the dose for 1% clonogenic survival, D0.01, based on colonies/clusters with >or=10 cells. Fibroblast proliferative capability was represented by binucleation index (BNI) and genomic damage was expressed in terms of micronucleus frequency. Wound healing complications (WHC) and subcutaneous fibrosis were the clinical endpoints examined. The ability of each in vitro parameter to detect patients at high risk of a given normal tissue complication was assessed using receiver operating characteristic (ROC) analysis. RESULTS: While fibroblasts from patients without WHC were marginally more radiosensitive than fibroblasts from patients with WHC (P=0.08), the reduction in BNI following a dose of 2.4 Gy was significantly higher in strains from patients without WHC compared to those from patients with WHC (P=0.01). The area under the ROC curve (c-index) is indicative of the power of discrimination of D0.01 and BNI for WHC, and was found to be 0.68 and 0.79, respectively. Subcutaneous fibrosis was not associated with D0.01 (rs=0.09, P=0.66) and the percent reduction in BNI after 2.4 Gy (rs=-0.19, P=0.36). Micronucleus frequency did not reflect differences in normal tissue responses. CONCLUSION: These data suggest that it is the ability of fibroblasts to undergo one-three divisions in vitro following radiation treatment that may reflect the development of wound healing morbidity or subcutaneous fibrosis in this population of patients.

Adult↗
PubMed2004

Factors associated with prognosis of lateral epicondylitis after 8 weeks of physical therapy.

OBJECTIVE: To identify key factors associated with outcomes of patients who underwent 8 weeks of physical therapy (PT) for lateral epicondylitis. DESIGN: Multicenter prospective design with inception cohort of lateral epicondylitis patients commencing PT. Baseline clinical examinations were conducted by 1 physical therapist; self-report outcome measures were completed at baseline and 8 weeks later. SETTING: Nine private sports medicine clinics and 2 hospital outpatient departments in Ontario, Canada. PARTICIPANTS: Eighty-three patients with unilateral lateral epicondylitis identified by the treating physical therapists. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The final scores of the Disability of the Arm, Shoulder and Hand (DASH) questionnaire and a vertical pain visual analog scale (VAS) were used as the dependent variables. RESULTS: The final prognostic model for the 8-week DASH scores included the baseline score (95% confidence interval [CI], 0.34-0.66), sex (female) (95% CI, 3.3-14.5), and self-reported nerve symptoms (95% CI, 0.8-13.8). The model for the 8-week VAS scores included the baseline score (95% CI, 0.01-0.37), sex (female) (95% CI, 0.4-18.2), and self-reported nerve symptoms (95% CI, 4.7-25.5). A subanalysis indicated that women were more likely than men to have work-related onsets, repetitive keyboarding jobs, and cervical joint signs. Among women, these factors were associated with higher final DASH and VAS scores. CONCLUSIONS: Women and patients who report nerve symptoms are more likely to experience a poorer short-term outcome after PT management of lateral epicondylitis. Work-related onsets, repetitive keyboarding jobs, and cervical joint signs have a prognostic influence on women.

Adult↗
PubMed2004

Computer use associated with poor long-term prognosis of conservatively managed lateral epicondylalgia.

STUDY DESIGN: Multicenter prospective design with a cohort of patients with lateral epicondylalgia commencing physical therapy. OBJECTIVE: To identify key factors associated with long-term prognosis of conservatively managed lateral epicondylalgia. BACKGROUND: The response to conservative management of lateral epicondylalgia is inconsistent and the rate of recovery varies widely among individuals. The reasons for these discrepancies are not understood. The identification of factors associated with prognosis will aid in the prediction of patient outcomes. METHODS AND MEASURES: Sixty patients with lateral epicondylalgia, recruited from 9 sports medicine clinics and 2 hospital outpatient physical therapy departments in Ontario, Canada, were followed for 6 months. A baseline clinical assessment was conducted on each participant using standard physical therapy techniques. The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and a 100-mm pain visual analog scale (VAS) were completed at baseline and 6 months later. RESULTS: The key factor associated with both 6-month DASH and pain VAS scores was repetitive-work tasks (DASH, 9.8 [P < .011; pain VAS, 13.1 mm [P = .0105]). A subanalysis indicated that women were more likely than men to have cervical joint signs and, among women, positive cervical articular signs were also associated with higher final DASH and pain VAS scores. CONCLUSIONS: Although many of the participants identified sports activities as the cause of their injury, these findings emphasize the importance that a patient's work tasks can have on recovery of lateral epicondylalgia. This would suggest that management should perhaps focus on work stations, postures, and behaviors.

Adult↗
PubMed2003

The influence of anatomic location on outcome in patients with soft tissue sarcoma of the extremity.

BACKGROUND: The anatomic location of an extremity soft tissue sarcoma may influence the patient's presentation, management, and local and systemic recurrence rates. The objective of this study was to compare the presentation, management, and outcome of patients with soft tissue sarcomas of the upper extremity and the lower extremity. METHODS: Prospectively collected data from patients who underwent limb-sparing surgery for extremity soft tissue sarcoma between January, 1986 and April, 1997 were analyzed. Local recurrence free rates and metastasis free rates were calculated using the method of Kaplan and Meier. Univariate and multivariate analyses of potential predictive factors were evaluated with the log-rank test and the Cox proportional hazards model. RESULTS: Of 480 eligible patients, 48 patients (10.0%) had a local recurrence, and 131 patients (27.3%) developed distant metastasis. The median follow-up of survivors was 4.8 years (range, 0.1-12.9 years). Patients with upper extremity tumors had smaller lesions (6.0 cm vs. 9.3 cm; P < 0.001), more often underwent unplanned excision before referral (89 patients [64.0%] vs. 160 patients [46.9%]; P < 0.001), and less often received radiotherapy (98 patients [70.5%] vs. 289 patients [84.8%]; P < 0.001). The 5-year local recurrence free rate was 82% for patients with sarcomas of the upper extremity and 93% for patients with sarcomas of the lower extremity (P = 0.002). The 5-year metastasis free rate was 82% for patients with sarcomas of the upper extremity and 69% for patients with sarcomas of the lower extremity (P = 0.013). CONCLUSIONS: Local recurrence was more frequent in patients who had sarcomas of the upper extremity compared with patients who had sarcomas of the lower extremity. Factors that contributed to this difference included histologic type, the use of radiotherapy, and local anatomy. Metastasis was more frequent among patients with sarcomas of the lower extremity, because those tumors tended to be large and deeper compared with upper extremity tumors.

Adolescent↗
PubMed2003

Large segment allograft survival is improved with intramedullary cement.

BACKGROUND AND OBJECTIVES: The most common cause of failure in large segment bone allografts used for oncologic reconstruction is allograft fracture. Reinforcement with pressurized intramedullary cement may improve the mechanical properties of allografts. METHODS: We reviewed the prospectively collected records of 45 patients who underwent en bloc resection of an extremity bone tumor and reconstruction using an allograft with intramedullary cement. RESULTS: Seven allografts were used for arthrodesis, 20 were intercalary, and 18 were osteochondral. Twenty eight of 45 patients were alive at a mean 5.8 years (SD 1.9; range 3-11.2) with 24 allografts in situ. In these 45 patients, there were four allograft fractures and four infections. Six of these complications resulted in allograft removal. The estimated 5-year allograft survival rate was 86% (95% confidence interval 74-98%). Seven patients required secondary autogenous bone grafting for non-unions. Function measured by the Toronto Extremity Salvage Score and the 1987 and 1993 Musculoskeletal Tumor Society Rating Scales demonstrated a consistent pattern with worse function in patients with osteochondral allografts and best function with intercalary allografts. CONCLUSIONS: These results suggest the addition of intramedullary cement to large segment bone allografts improves their survival by decreasing the fracture risk, particularly for allografts used for arthrodesis and intercalary reconstructions.

Adolescent↗
PubMed2003

Measuring postirradiation subcutaneous soft-tissue fibrosis: state-of-the-art and future directions.

Clinician-based rating scales and quantitative instruments used to quantify the severity of soft-tissue fibrosis were reviewed to determine if they were reliable and valid measures for clinical and research use. Existing clinician-based measures, the Medical Research Council (MRC) and European Organization for Research and Treatment of Cancer/Radiation Therapy Oncology Group (EORTC/RTOG), have preliminary testing of reliability and validity such that they provided a basis for the development of a revised measure. The revised measure, designed for use in National Cancer Institute-Common Toxicity Criteria for Adverse Events v3.0, evaluates subcutaneous and deep-tissue fibrosis separately and each is graded on a 5-point scale. The revised measure needs to be tested for reliability and validity, and it is recommended that it be used in concert with the MRC and/or EORTC/RTOG scales until such evidence is available and its utility can be determined. Quantitative measures, although attractive from a research perspective, will have limited clinical and multisite utility because of the apparatus required and the associated costs. Finally, a framework for evaluating fibrosis and the consequences of fibrosis is presented.

Humans↗
PubMed2003

Work status after distal femoral Kotz reconstruction for malignant tumors of bone.

OBJECTIVE: To determine the proportion of patients who experienced altered work status after reconstruction with a modular tumor prosthesis and adjuvant chemotherapy for primary sarcoma of the distal femur. DESIGN: We reviewed an institution's tumor database and patients' charts. Disability and work status data were collected preoperatively, at 1 year and 2 years postoperatively and at final follow-up. SETTING: Acute-care teaching hospital in Ontario, Canada. PARTICIPANTS: Thirty-six eligible patients. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Work status was plotted over time to identify unexpected deviations (based on age and preoperative status), and subjects were assigned to altered work status (defined by detrimental changes in productivity, eg, change from full-time work to not working) or expected work status (defined by ongoing work or students progressing to higher education). Disability was measured with the Toronto Extremity Salvage Score and the Musculoskeletal Tumor Society score. RESULTS: Nine patients (25%) experienced altered work status. There were no significant differences in disability ratings or demographic information between the 2 groups. Baseline job demand and living environment (rural vs urban, P=.001) were predictive by logistic regression. CONCLUSIONS: Patients with physically demanding jobs, and those living rurally, are at greatest risk for altered work status.

Adolescent↗
PubMed2003

Classifying failed hip arthroplasty: generalizability of reliability and validity.

Interrater reliability and validity of a radiographic severity classification was evaluated in 81 patients having revision hip arthroplasty. Severity was rated separately on the femoral and acetabular sides using a five-level scale ranging from no significant loss of bone stock to uncontained loss of bone stock and discontinuity. Three academic orthopaedic surgeons rated preoperative anteroposterior radiographs taken within 6 weeks of surgery. Interrater reliability was 0.54 (weighted kappa) with 57% agreement on the acetabular side and 0.56 with 52% agreement on the femoral side. Rater to intraoperative findings agreed 45% of the time and weighted kappa was 0.41 on the acetabular side and agreed 38% of the time with weighted kappa of 0.39 on the femoral side. When radiographic and intraoperative ratings disagreed, 30% of the time no bony defect was found on the acetabular side. Fifty-eight percent of femoral radiographic ratings were upgraded intraoperatively. These results differ from previously reported results of high reliability from one institution with trained raters. A reliable and valid severity classification that is generalizable to multiple raters from different institutions is required to stratify patients for intervention studies, and to aid preoperative planning. Training in the classification system may improve generalizability.

Adult↗
PubMed2002

Preoperative versus postoperative radiotherapy in soft-tissue sarcoma of the limbs: a randomised trial.

BACKGROUND: External-beam radiotherapy (delivered either preoperatively or postoperatively) is frequently used in local management of sarcomas in the soft tissue of limbs, but the two approaches differ substantially in their potential toxic effects. We aimed to determine whether the timing of external-beam radiotherapy affected the number of wound healing complications in soft-tissue sarcoma in the limbs of adults. METHODS: After stratification by tumour size (< or = 10 cm or >10 cm), we randomly allocated 94 patients to preoperative radiotherapy (50 Gy in 25 fractions) and 96 to postoperative radiotherapy (66 Gy in 33 fractions). The primary endpoint was rate of wound complications within 120 days of surgery. Analyses were per protocol for primary outcomes and by intention to treat for secondary outcomes. FINDINGS: Median follow-up was 3.3 years (range 0.27-5.6). Four patients, all in the preoperative group, did not undergo protocol surgery and were not evaluable for the primary outcome. Of those patients who were eligible and evaluable, wound complications were recorded in 31 (35%) of 88 in the preoperative group and 16 (17%) of 94 in the postoperative group (difference 18% [95% CI 5-30], p=0.01). Tumour size and anatomical site were also significant risk factors in multivariate analysis. Overall survival was slightly better in patients who had preoperative radiotherapy than in those who had postoperative treatment (p=0.0481). INTERPRETATION: Because preoperative radiotherapy is associated with a greater risk of wound complications than postoperative radiotherapy, the choice of regimen for patients with soft-tissue sarcoma should take into account the timing of surgery and radiotherapy, and the size and anatomical site of the tumour.

Aged↗
PubMed2002

Long-term clinical experience with fresh osteochondral allografts for articular knee defects in high demand patients.

Fresh osteochondral allografts are used to repair osteoarticular defects of the knee. For post-traumatic defects recent advances in other techniques for cartilage repair and resurfacing have reduced the role of allograft tissue transplantation to defects larger than 3 cm in diameter and 1 cm in depth.A fresh osteochondral allograft that has been harvested from a donor within 24 h from death and preserved in 4 degrees C for up to 4 days shows 100% viability of the cartilage. The avascular bone remains structurally intact and mechanically strong until it is replaced by host bone or until it is weakened or absorbed. The indications for fresh osteochondral allografts for reconstructive surgery of the articular surface of the knee do not justify the use of immunosuppressive drugs and we therefore believe that surgical vascularization of the grafts should not be carried out.This clinical approach can provide a reconstructive solution for younger higher demand patients where implants are not desirable and arthrodesis is not acceptable. A clinical follow-up study as early as 1975 showed successful early outcomes. More recently, survival analysis found 95% survival at 5 years, 71% at 10 years, and 66% at 20 years. It was learned that older patients, bipolar transplants, improper loading of the graft, and grafts for osteoarthritis and steroid-induced avascular necrosis do not lead to good long-term outcomes.We would like to describe here some of our long-term clinical experience concerning this surgery.

Journal Article↗
PubMed2002

A fresh osteochondral allograft alternative.

Fresh osteochondral allografts were used for post-traumatic knee defects >3 cm in diameter and 1 cm in depth. Harvesting of the grafts was carried out within 24 hours of the death of the donor, and implantation into the recipient was carried out within 72 hours. The grafts were unipolar, fixed by screws, and combined with realignment osteotomy if a deformity existed. Meniscal transplantation also was performed if indicated. The survivorship of all grafts (plateaus and condyles) at 7.5 years was 85%. The survivorship of femoral condyle grafts at 10 years was 85%. Viable hyaline cartilage has been confirmed at 17 years.

Adolescent↗
PubMed2002

Giant cell tumor of long bone: a Canadian Sarcoma Group study.

A multicentric retrospective study of giant cell tumor of bone was conducted among Canadian surgeons. The hypothesis was that no differences would be found in health status, function, or recurrence rate irrespective to the nature of filling material or adjuvant used in patients treated with curettage. One hundred eighty-six cases were collected. There were 96 females and 90 males. The mean age of the patients was 36 years (range, 14-72 years), the minimum followup was 24 months, and the median followup was 60 months. Sixty-two percent of the tumors involved the knee region. One hundred fifty-eight were primary tumors and 28 were recurrences. Campanacci grading was as follows: Grade 1, seven patients; Grade 2, 100 patients; Grade 3, 76 patients; and unknown in three patients. Fifty-six patients had a pathologic fracture. Resection was done in 38 patients and 148 patients had curettage. The latter was supplemented with high speed burring in 135 patients, cement in 64 patients, various combinations of autograft or allograft bone in 61 patients, phenol in 37 patients, and liquid nitrogen in 10 patients. Structural allografts were used in 25 patients. The overall recurrence rate was 17%, 18% after curettage, and 16% after resection. Patients with primary tumors treated with curettage had a 10% recurrence rate. For recurrent lesions treated by curettage, the recurrence rate was 35%. The nature of the filling material used or the type of adjuvant method used or any combination of both failed to show any statistical impact on the recurrence risk. The results from the Musculoskeletal Tumor Society rating from 1987 were significantly lower in patients who sustained a displaced fracture. Results from the bodily pain section of the Short Form-36 also were found to be lower when a pathologic fracture was present. Results from the Musculoskeletal Tumor Society Rating 1987, the Short Form-36, and the Toronto Extremity Salvage Score did not show differences when either cement or bone graft were used after curettage.

Adolescent↗