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Hans J Kreder

Publications and source records attributed to Hans J Kreder.

At least 19 recordsLinked to original sources
PubMed2006

A randomized, controlled trial of distal radius fractures with metaphyseal displacement but without joint incongruity: closed reduction and casting versus closed reduction, spanning external fixation, and optional percutaneous K-wires.

OBJECTIVES: To compare closed reduction and casting with closed reduction and external fixation with optional K-wire fixation for distal radius fractures with metaphyseal displacement but without joint incongruity. DESIGN: Prospective study. SETTING: Multicenter study at 3 University teaching hospitals. PATIENTS/PARTICIPANTS: A total of 113 skeletally mature patients with distal radius fractures with metaphyseal displacement, but without joint incongruity, were randomized to receive 1 of 2 standardized treatment protocols. Patients were evaluated at 6 weeks, 6 months, 1 year, and 2 years. INTERVENTION: Closed reduction and casting (n = 59) or closed reduction and external fixation (n = 54). MAIN OUTCOME MEASUREMENTS: Upper extremity function was measured using upper extremity MFA domain scores, overall Jebsen Taylor scores, and pinch and grip strength tests. Global function and pain were measured using the SF-36. Radiographic evaluation and range of motion were documented. RESULTS: Upper extremity MFA scores, Jebsen Taylor scores, SF-36 bodily pain scores, and grip strength improved significantly during the first year for all patients. By 2 years, mean Jebsen Taylor scores and SF 36 bodily pain scores for patients in both groups were similar to scores for normal age- and gender-matched population controls. At all points, there was a trend for better function in the external fixation; however, this did not reach statistical significance. There was a trend for better length and palmar tilt restoration with external fixation. CONCLUSIONS: For distal radius fractures with metaphyseal displacement but with a congruous joint, there exists a trend for better functional, clinical, and radiographic outcomes when treated by immediate external fixation and optional K-wire fixation.

Adult↗
PubMed2006

Factors associated with outcome after subtalar arthrodesis.

OBJECTIVES: To evaluate radiographic and functional outcomes after subtalar arthrodesis and to identify patient factors associated with poor outcome. DESIGN: Retrospective study. SETTING: Two academic hospitals. PATIENTS: Eighty-eight patients with primary or secondary osteoarthritis treated between 1995 and 2002. INTERVENTION: Primary subtalar arthrodesis. MAIN OUTCOME MEASUREMENTS: Radiographic outcome was assessed by determining union rates. Functional outcome was assessed through self-administered questionnaires (Short Form-36, Short Musculoskeletal Function Assessment, and the AAOS Foot and Ankle Instrument). RESULTS: After adjusting for age and sex smokers were 3.8 times more likely to go on to nonunion than nonsmokers (P < 0.05). As patients aged, there was a higher likelihood of nonunion if they also smoked (P < 0.05). Of patients undergoing subtalar bone block distraction arthrodesis 95% went on to union compared with 65% of patients treated with an in situ subtalar arthrodesis without bone graft (P < 0.05). There was a trend for higher rates of union if a bone graft was used among patients treated with an in situ subtalar arthrodesis. Diabetic patients were 18.7 times more likely to have a malunion (P < 0.05). As a group, patients who have undergone subtalar arthrodesis can expect significantly worse functional outcomes compared with the Canadian and American normative populations. The poorest functional outcomes were observed among patients with diabetes. A trend for poorer outcome in bodily pain and general health (Short Form-36) was seen in workers' compensation patients. CONCLUSIONS: Certain patient variables are associated with poorer outcomes after subtalar fusion. The results of this study will enable surgeons to provide better information to patients in preoperative discussions with respect to patient expectations, outcomes, and the success of surgery.

Adult↗
PubMed2006

Deficits following nonoperative treatment of displaced midshaft clavicular fractures.

BACKGROUND: Displaced fractures of the midpart of the clavicular shaft are generally treated nonoperatively, and few functional deficits have been reported. Whereas prior investigators have presented radiographic and surgeon-based outcomes, we used a patient-based outcome questionnaire and objective muscle-strength testing to evaluate a series of patients who had received nonoperative care for a displaced midshaft fracture of the clavicle. METHODS: We identified thirty patients (twenty-two men and eight women with a mean age of thirty-seven years) who had sustained a displaced midshaft fracture of the clavicle. All patients were treated nonoperatively. At a mean of fifty-five months, and a minimum of twelve months, outcomes were measured with the Constant shoulder score and the DASH (Disabilities of the Arm, Shoulder and Hand) patient questionnaire. In addition, objective shoulder muscle-strength testing was performed with the Baltimore Therapeutic Equipment Work Simulator, with the uninjured arm serving as a control. RESULTS: The range of motion was well maintained, with flexion averaging 170 degrees +/- 20 degrees and abduction averaging 165 degrees +/- 25 degrees . Compared with the strength of the uninjured shoulder, the strength of the injured shoulder was reduced to 81% for maximum flexion, 75% for endurance of flexion, 82% for maximum abduction, 67% for endurance of abduction, 81% for maximum external rotation, 82% for endurance of external rotation, 85% for maximum internal rotation, and 78% for endurance of internal rotation (p < 0.05 for all values). The mean Constant score was 71 points, and the mean DASH score was 24.6 points, indicating substantial residual disability. CONCLUSIONS: Traditionally, good results with minimal functional deficits have been reported following nonoperative treatment of clavicular fractures. However, surgeon-based methods of evaluation may be insensitive to loss of muscle strength. We detected residual deficits in shoulder strength and endurance in this patient population, which may be related to the significant level of dysfunction detected by the patient-based outcome measures.

Adult↗
PubMed2005

Arthroplasty in the octogenarian: quantifying the risks.

The objective of this study was to determine the risk of complications after primary total hip and knee arthroplasties in octogenarians. Using administrative data, we compared the rate of complications for octogenarians vs patients aged 65 to 79 years who underwent total hip or knee arthroplasty in Ontario between 1993 and 1997. Octogenarians were 3.4 times more likely to die, 2.7 times more likely to sustain a myocardial infarction, and 3.5 times more likely to develop pneumonia. Postoperative confusion and urinary tract infections were also significantly more common in octogenarians. Octogenarians are at higher risk for death and serious complications after primary joint arthroplasty. However, the overall event rate remains low and total joint arthroplasty surgery should continue to be offered to these individuals provided that the complication rates are acceptable to the patients and their families.

Aged↗
PubMed2005

Unstable pertrochanteric femoral fractures.

BACKGROUND: Fractures in the trochanteric region of the femur are classified as AO/OTA 31-A, as they are extracapsular. This report analyzes the relatively rare 31-A3 fracture, which has also been referred to as an "intertrochanteric femur fracture with subtrochanteric extension," "reverse obliquity intertrochanteric femur fracture," "unstable intertrochanteric femur fracture," or a "subtrochanteric femur fracture." The A3 fracture is characterized by having a fracture line exiting the lateral femoral cortex distal to the vastus ridge. Possible fixation constructs include compression hip screws, intramedullary hip screws, trochanteric intramedullary nails, cephalomedullary antegrade intramedullary nails, and 95 degrees plates. Most reports investigating 31-A fractures do not describe the 31-A3 fracture. For this analysis, only reports clearly indicating that the fracture treated was a 31-A3 were included. It should be understood that this approach therefore excludes reports on generic "subtrochanteric fractures" or "intertrochanteric fractures," some of which may have been 31-A3 fractures. OBJECTIVE: To determine the effect of fixation technique for the AO/OTA 31-A3 fracture on rates of union, infection, risk of reoperation, and functional outcomes.

Fracture Fixation, Internal↗
PubMed2005

Pelvic reconstruction for massive acetabular insufficiency.

Joint reconstruction for pelvic discontinuity because of massive acetabular insufficiency presents a significant surgical challenge. Using retrograde-inserted Steinmann pins to rebuild the dome may be associated with early implant failure because of insufficient mechanical stability and neurovascular injury resulting from pin misplacement. Retrograde pins cannot be placed completely across the pelvic defect. We hypothesized that large Steinmann pins placed anterograde under direct vision from the iliac crest completely across the acetabular column and floor defects would minimize the risk of early failure, and could be placed safely without the use of fluoroscopy in combination with a posterior hip approach. The purpose of our study was to review the mechanical failure and complication rates of nine patients (10 hips) treated between 1996 and 2002 for pelvic discontinuity using this pin placement technique to reinforce a cemented roof ring hip reconstruction done via a posterior approach. None of the patients had implant loosening or failure, there were no neurovascular complications, and no perioperative deaths. One patient required cup revision for recurrent dislocation. All patients were bedridden or wheelchair-bound before surgery, but regained independent household walking by 6 weeks postoperatively. Reinforcing the acetabulum with a lattice girder of anterograde pins provides safe and effective hip reconstruction.

Acetabulum↗
PubMed2005

Bilateral total knee arthroplasty--staged or simultaneous? Ontario's orthopedic surgeons reply.

BACKGROUND: Total knee replacement is now the most common joint replacement procedure performed in Ontario, and many patients require bilateral replacement. However, whether bilateral total knee arthroplasty (TKA) should be staged or simultaneous is hotly debated. To determine the current common operative practices of orthopedic surgeons in Ontario, we carried out a province-wide survey. METHODS: Orthopedic surgeons from Ontario listed in the 1999 Canadian Medical Directory or the membership list of the Canadian Orthopaedic Association were sent questionnaires, asking about their practice in the timing of bilateral TKA, tourniquet use, type of guide and use of techniques to minimize fat embolization. RESULTS: Of the 416 surveys mailed, 219 (53%) surgeons responded. The majority responded that they perform staged bilateral TKA (28% 3-mo interval and 37% 6-mo interval). Simultaneous TKA with 2 teams was the least performed procedure (2%). When performing bilateral TKA, 95% of surgeons use an intramedullary femoral alignment guide, 78% utilize an over-reamed entry hole and 53% suction the canal before inserting the guide rod. With respect to the tibia, 32% use an intramedullary guide, 60% over-ream the entry hole and 60% suction the entry hole; 22% of surgeons stated that they had never considered over-reaming or suctioning the canal to minimize fat embolization. CONCLUSIONS: There is no consensus regarding the timing of bilateral TKA in Ontario. Furthermore, many surgeons are not overdrilling or suctioning the femoral canal despite evidence in the literature that overdrilling may be beneficial in decreasing fat embolization. Further research is required to compare the risk of complications of bilateral TKA after staged versus simultaneous TKA.

Arthritis↗
PubMed2004

The moving target: a qualitative study of elderly patients' decision-making regarding total joint replacement surgery.

BACKGROUND: Total joint replacement is an accepted, cost-effective, and underutilized treatment for moderate-to-severe hip and knee arthritis. Yet, research has suggested that many patients with arthritis are unwilling to consider total joint replacement surgery. We sought to understand these patients' unwillingness by exploring the nature of their decision-making processes. METHODS: In-depth interviews were conducted with seventeen individuals with moderate-to-severe arthritis who were appropriate candidates for, but unwilling to consider, total joint replacement. The interviews were analyzed with use of qualitative methods and content analysis techniques. RESULTS: Symptoms and information sources were the two main factors influencing patient decision-making. Participants engaged in individualized processes of trading off perceived costs and benefits. Accommodation to pain and disability and minimization of the quality-of-life benefit, in view of decreasing life span, led to a process whereby the threshold at which the benefits compared with the risks would tilt in favor of total joint replacement was constantly shifting, a phenomenon we called "the moving target." CONCLUSIONS AND CLINICAL RELEVANCE: The moving-target characterization sheds light on patients' conceptions of their arthritis and on their unwillingness to consider total joint replacement. This process needs to be considered when developing ways to aid decision-making.

Age Factors↗
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↗
PubMed2003

Provider volume and other predictors of outcome after total knee arthroplasty: a population study in Ontario.

INTRODUCTION: Because of rationing of the limited pool of health care resources, access to total knee arthroplasty (TKA) is limited, but investigation of variables that predict complications, length of hospital stay, cost and outcomes of TKA may allow us to optimize the available resources. The objective of this study was to examine the effect of various factors on complication rates after TKA in patients managed in Ontario. METHODS: Patients who had undergone an elective TKA between 1993 and 1996, as captured in the Canadian Institute for Health Information (CIHI) database, formed the study cohort. The CIHI dataset was used to obtain information regarding in-hospital complications, hospital length of stay, revision rates, infection rates and mortality. Generalized estimating linear or logistic regression equations were used to model outcomes as a function of age, gender, comorbidity, diagnosis and provider volume. RESULTS: During the study period, 14,352 patients in Ontario underwent TKA. Mortality at 3 months was associated with patient age, gender and comorbidity. There was no association between provider volume and mortality or the infection rate. Higher revision rates at 1 and 3 years were significantly associated with lower patient age and low hospital volume (p < 0.05). Hospitals in which fewer than 48 TKA procedures were done per year (< 40th percentile) had 2.2-fold greater 1-year revision rates than hospitals performing more than 113 TKAs annually (> 80th percentile). Complications during admission were associated with increased patient age and comorbidity, and higher hospital volume. Longer hospital stay was associated with female gender, increasing patient comorbidity and age, and lower provider volume. Surgeons who performed fewer than 14 TKAs annually (< 40th percentile) kept patients in hospital an average of 1.4 days longer than surgeons performing more than 42 TKAs annually (> 80th percentile). CONCLUSIONS: Patient variables significantly affect the rate of complications. Age, sex and comorbidity were significant predictors of complications, length of hospital stay and mortality after TKA. Although low surgeon volume was related to longer hospital stay, there was no association between surgeon volume and complication rates. The increased early revision rate for low-volume hospitals demands further study.

Aged↗
PubMed2003

Venting during prophylactic nailing for femoral metastases: current orthopedic practice.

INTRODUCTION: Reamed intramedullary nailing, recommended for impending fracture of a femur weakened by bone metastases, causes a rise in intramedullary pressure and increases the risk of a fat embolism syndrome. The pressure can be equalized by the technique of venting--drilling a hole into the distal cortex of the femur. Our objective was to study the current practice of orthopedic surgeons in Ontario with respect to venting during prophylactic intramedullary nailing for an impending femoral fracture due to bone metastases. METHODS: We mailed a questionnaire to all orthopedic surgeons from the Province of Ontario listed in the 1999 Canadian Medical Directory or on the Canadian Orthopaedic Association membership list, asking if they vent when prophylactically nailing an impending pathologic femoral fracture. The responses were modelled as a function of surgeon volume and year of graduation. RESULTS: Of the 415 surveys mailed, 223 (54%) surgeons responded. Of these, 81% reported having prophylactically treated a femoral metastatic lesion during the previous year; 67% treated 1 to 3 metastatic lesions and 14% treated more than 3; 19% did not treat a metastatic femoral lesion prophylactically. Over two-thirds of surgeons had never considered venting, whereas one-third always or sometimes vented the femoral canal. More recent graduates were 3 times more likely to vent than earlier (before 1980) graduates (odds ratio [OR] = 3.2, 95% confidence interval [CI] 1.6-6.5) as were those who treat a greater number of impending fractures (OR = 1.4, 95% CI 1.1-1.7). CONCLUSIONS: Although there is a theoretical rationale for routine venting, there is disagreement among Ontario orthopedic surgeons regarding the use of this technique during prophylactic nailing for femoral metastatic lesions. Prospective evidence will be required to warrant a change in the standard of care.

Attitude of Health Personnel↗
PubMed2002

Nonoperative treatment of hip fractures.

We retrospectively reviewed a population database and a case series to compare the mortality of operative and nonoperative treatment of hip fractures in patients with severe comorbidity. Nonoperative treatment of hip fractures (bed rest or early weight bearing) was administered based on medical assessment of perioperative risk. Comparison of 30-day mortality was performed between the nonoperatively and operatively treated groups. We found that of 50,235 of hip fractures that occurred between 1992 and 1998, 89.4% were treated operatively. Thirty-day mortality rate in the nonoperatively treated patients (18.8%) was higher than the rate in operatively treated patients (11.0%) (odds ratio 1.7 times, 95% confidence interval (CI) 1.6, 1.8). In the case series, of 62 elderly patients with severe comorbidity treated nonoperatively, 41 had bed rest/traction, while 21 were mobilized early. A group of operatively treated patients (n=108) was compared to nonoperatively treated patients. Mortality with nonoperative treatment was higher with bed rest (73%) compared to early mobilization (odds ratio 3.8, 95% CI 1.1-14.0). There was no significant difference in mortality between operatively treated patients (29%) and patients treated nonoperatively with immediate mobilization (19%). Bed rest was 2.5 times more likely to be associated with mortality compared to operative treatment (95% CI 1.1-5.5).

Aged↗
PubMed2002

Arthroscopic débridement of the knee for osteoarthritis in patients fifty years of age or older: utilization and outcomes in the Province of Ontario.

BACKGROUND: There is little available information regarding the effectiveness of arthroscopic knee débridement for the treatment of arthritis. The purpose of this study was to evaluate patterns of utilization of arthroscopic knee débridement and outcomes following that procedure for the treatment of degenerative arthritis in persons fifty years of age or older in the Province of Ontario. METHODS: All patients fifty years of age or older who underwent elective arthroscopic knee débridement for the treatment of degenerative arthritis between 1992 and 1996 were identified from administrative data sets. Surgical complications and subsequent knee replacements were noted. Population rates were compared across the sixteen District Health Council regions within Ontario. Outcomes were modeled as a function of patient age, gender, and comorbidity with use of multivariate regression analysis. RESULTS: We identified 14,391 eligible unilateral arthroscopic knee débridement procedures. There was a threefold difference in the population rate of arthroscopic débridement across geographic regions. Overall, 1330 (9.2%) of all patients required total knee arthroplasty within one year after the débridement. Of the 6212 patients with a minimum three-year follow-up, 1146 (18.4%) had undergone total knee replacement within three years following the débridement. Patients who were at least seventy years of age were 4.7 times more likely to have total knee arthroplasty within one year after the débridement than were those less than sixty years of age (19.0% compared with 4.0%; p < 0.05). Patients sixty years of age or older were more likely to have an early total knee replacement (within one year after the débridement) in District Health Council regions where the population rates of arthroscopic knee débridement were higher (p = 0.04). CONCLUSIONS: The higher rates of early total knee arthroplasty and the significant relationship between rates of early total knee arthroplasty and rates of utilization suggest that arthroscopic débridement for the treatment of osteoarthritis of the knee may be overutilized in elderly patients. Important clinical issues such as patient preference, risk perception, and functional outcome cannot be addressed just with the administrative data used for this study.

Age Factors↗
PubMed2002

Femoral intramedullary nailing: comparison of fracture-table and manual traction. a prospective, randomized study.

BACKGROUND: The purpose of this study was to compare manual traction and fracture-table traction for the reduction and nailing of femoral shaft fractures. We evaluated the quality of the reduction, operative time, complications, and functional status of the patient. METHODS: Eighty-seven consecutive adult patients with a unilateral fracture of the femoral diaphysis that did not extend into the knee joint or proximal to the lesser trochanter were enrolled in the study. Patients who were transferred to our institution more than forty-eight hours after injury; those with multiple-system injuries, injury to the ipsilateral lower extremity, or pathological fracture; and those who were unable or unwilling to provide consent or to return for follow-up were excluded. Forty-five patients were randomized to manual traction and forty-two, to fracture-table traction; all were treated in the supine position. The number of surgical assistants, operative and fluoroscopy time, complications, functional scores, and other outcomes were recorded. RESULTS: There were no significant differences between the groups with respect to age, gender, Glasgow Coma Score, Injury Severity Score, side or mechanism of injury, fracture type, or time from injury to treatment. Internal malrotation was significantly more common when the fracture table had been used: twelve (29%) of the forty-two femora were internally rotated by >10 compared with three (7%) of the forty-five treated with manual traction (p = 0.007). Total operative time, from the beginning of the patient positioning to the completion of the skin closure, was decreased from a mean of 139 minutes (range, 100 to 212 minutes) when the fracture table was used to a mean of 119 minutes (range, sixty-five to 180 minutes) when manual traction was used (p = 0.033). There was no significant difference between the two treatment groups with regard to the number of assistants per case (mean two; range, zero to three), fluoroscopy time, other complications including femoral shortening or lengthening, or functional status of the patient at one year. CONCLUSIONS: Compared with fracture-table traction with the patient in a supine position, manual traction for intramedullary nailing of isolated fractures of the femoral shaft is an effective technique that decreases operative time and improves the quality of the reduction.

Adolescent↗
PubMed2002

Comparison of early and delayed fixation of subcapital hip fractures in patients sixty years of age or less.

BACKGROUND: Subcapital hip fractures in younger patients are generally treated with internal fixation rather than with primary hemiarthroplasty, which is generally reserved for older, low-demand patients. Avascular necrosis can occur following this injury because of disruption of the femoral head blood supply. Some believe that emergent fracture reduction is necessary to minimize the risk of avascular necrosis. The purposes of this study were (1) to investigate the functional outcomes of subcapital hip fractures in patients sixty years old or younger and (2) to compare the rates of avascular necrosis after early and delayed fracture fixation. METHODS: This retrospective study included adults in whom a subcapital hip fracture had been treated with reduction and internal fixation when they were sixty years of age or less and who had been followed clinically for a minimum of two years. The patients were divided into two groups: those treated with early fixation (within twelve hours after the injury) and those treated with delayed fixation (more than twelve hours after the injury). Functional outcomes were assessed with use of the Short Form-36 and the Western Ontario and McMaster University (WOMAC) Osteoarthritis Index. The rates of avascular necrosis were compared between the two groups. RESULTS: Thirty-eight patients (average age, 46.4 years) participated in the study. Twenty-nine patients had a displaced subcapital hip fracture. Fifteen patients underwent early fracture fixation, and the remainder underwent delayed fixation. No differences in the Short Form-36 (p = 0.68) or WOMAC (p = 0.69) scores were seen between the early and delayed fixation groups. Radiographic evidence of avascular necrosis developed in six patients treated with delayed fixation, one of whom had had an undisplaced fracture preoperatively, and in no patient treated with early fixation. The difference in the rates of avascular necrosis was significant (p = 0.03). CONCLUSIONS: Although delayed surgical treatment of subcapital hip fractures was associated with a higher rate of avascular necrosis, this complication did not significantly affect functional outcome. Longer follow-up is required to assess the effect of avascular necrosis on the development of arthritis and on long-term patient function. Although the results could be biased because patients were not randomly assigned to delayed or early fixation, the data suggest that urgent reduction and fracture fixation within twelve hours after a displaced subcapital hip fracture in high-demand patients may be associated with a reduced rate of radiographic signs of avascular necrosis.

Adult↗