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Showing papers in "Journal of Bone and Joint Surgery, American Volume in 2005"


Journal ArticleDOI
TL;DR: A comparison of item-reduction approaches suggested that the retention of clinically sensible and important content produced a comparable, if not slightly better, instrument than did more statistically driven approaches.
Abstract: Background: The purpose of this study was to develop a short, reliable, and valid measure of physical function and symptoms related to upper-limb musculoskeletal disorders by shortening the full, thirty-item DASH (Disabilities of the Arm, Shoulder and Hand) Outcome Measure. Methods: Three item-reduction techniques were used on the cross-sectional field-testing data derived from a study of 407 patients with various upper-limb conditions. These techniques were the concept-retention method, the equidiscriminative item-total correlation, and the item response theory (Rasch modeling). Three eleven-item scales were created. Data from a longitudinal cohort study in which the DASH questionnaire was administered to 200 patients with shoulder and wrist/hand disorders were then used to assess the reliability (Cronbach alpha and test-retest reliability) and validity (cross-sectional and longitudinal construct) of the three scales. Results were compared with those derived with the full DASH. Results: The three versions were comparable with regard to their measurement properties. All had a Cronbach alpha of ≥0.92 and an intraclass correlation coefficient of ≥0.94. Evidence of construct validity was established (r ≥ 0.64 with single-item indices of pain and function). The concept-retention method, the most subjective of the approaches to item reduction, ranked highest in terms of its similarity to the original DASH. Conclusions: The concept-retention version is named the QuickDASH. It contains eleven items and is similar with regard to scores and properties to the full DASH. A comparison of item-reduction approaches suggested that the retention of clinically sensible and important content produced a comparable, if not slightly better, instrument than did more statistically driven approaches. Clinical Relevance: The QuickDASH is a more efficient version of the DASH outcome measure that appears to retain its measurement properties.

1,429 citations


Journal ArticleDOI
Steven M. Kurtz1, Fionna Mowat1, Kevin L. Ong1, Nathan Chan1, Edmund Lau1, Michael T. Halpern1 
TL;DR: The number and prevalence of primary hip and knee replacements increased substantially in the United States between 1990 and 2002, but the trend was considerably more pronounced for primary total knee arthroplasty.
Abstract: Background: The purpose of this study was to quantify the procedural rate and revision burden of total hip and knee arthroplasty in the United States and to determine if the age or gender-based procedural rates and overall revision burden are changing over time. Methods: The National Hospital Discharge Survey (NHDS) for 1990 through 2002 was used in conjunction with United States Census data to quantify the rates of primary and revision arthroplasty as a function of age and gender within the United States with use of methodology published by the American Academy of Orthopaedic Surgeons. Poisson regression analysis was used to evaluate the procedural rate and to determine year-to-year trends in primary and revision arthroplasty rates as a function of both age and gender. Results: Both the number and the rate of total hip and knee arthroplasties (particularly knee arthroplasties) increased steadily between 1990 and 2002. Over the thirteen years, the rate of primary total hip arthroplasties per 100,000 persons increased by approximately 50%, whereas the corresponding rate of primary total knee arthroplasties almost tripled. The rate of revision total hip arthroplasties increased by 3.7 procedures per 100,000 persons per decade, and that of revision total knee arthroplasties, by 5.4 procedures per 100,000 persons per decade. However, the mean revision burden of 17.5% for total hip arthroplasty was more than twice that for total knee arthroplasty (8.2%), and this did not change substantially over time. Conclusions: The number and prevalence of primary hip and knee replacements increased substantially in the United States between 1990 and 2002, but the trend was considerably more pronounced for primary total knee arthroplasty. Clinical Relevance: The reported prevalence trends have important ramifications with regard to the number of joint replacements expected to be performed by orthopaedic surgeons in the future. Because the revision burden has been relatively constant over time, we can expect that a greater number of primary replacements will result in a greater number of revisions unless some limiting mechanism can be successfully implemented to reduce the future revision burden.

1,325 citations


Journal ArticleDOI
TL;DR: The hypothesis was that arthroscopic repair of full-thickness supraspinatus tears achieves a rate of complete tendon healing equivalent to those reported in the literature with open or mini-open techniques.
Abstract: Background: Good functional results have been reported for arthroscopic repair of rotator cuff tears, but the rate of tendon-to-bone healing is still unknown. Our hypothesis was that arthroscopic repair of full-thickness supraspinatus tears achieves a rate of complete tendon healing equivalent to those reported in the literature with open or mini-open techniques. Methods: Sixty-five consecutive shoulders with a chronic full-thickness supraspinatus tear were repaired arthroscopically in sixty-five patients with use of a tension-band suture technique. Patients ranged in age from twenty-nine to seventy-nine years. The average duration of follow-up was twenty-nine months. Fifty-one patients (fifty-one shoulders) had a computed tomographic arthrogram, and fourteen had a magnetic resonance imaging scan, performed between six months and three years after surgery. All patients were assessed with regard to function and the strength of the shoulder elevation. Results: The rotator cuff was completely healed and watertight in forty-six (71%) of the sixty-five patients and was partially healed in three. Although the supraspinatus tendon did not heal to the tuberosity in sixteen shoulders, the size of the persistent defect was smaller than the initial tear in fifteen. Sixty-two of the sixty-five patients were satisfied with the result. The Constant score improved from an average (and standard deviation) of 51.6 ± 10.6 points preoperatively to 83.8 ± 10.3 points at the time of the last follow-up evaluation (p < 0.001), and the average University of California at Los Angeles score improved from 11.5 ± 1.1 to 32.3 ± 1.3 (p < 0.001). The average strength of the shoulder elevation was significantly better (p = 0.001) when the tendon had healed (7.3 ± 2.9 kg) than when it had not (4.7 ± 1.9 kg). Factors that were negatively associated with tendon healing were increasing age and associated delamination of the subscapularis or infraspinatus tendon. Only ten (43%) of twenty-three patients over the age of sixty-five years had completely healed tendons (p < 0.001). Conclusions: Arthroscopic repair of an isolated supraspinatus detachment commonly leads to complete tendon healing. The absence of healing of the repaired rotator cuff is associated with inferior strength. Patients over the age of sixty-five years (p = 0.001) and patients with associated delamination of the subscapularis and/or the infraspinatus (p = 0.02) have significantly lower rates of healing. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

1,191 citations


Journal ArticleDOI
TL;DR: In this article, a study of the clinical data and periprosthetic tissues associated with endoprostheses with a metal-on-metal articulation that had been retrieved at revision was performed.
Abstract: Background: Some patients who have a total hip replacement with a second-generation metal-on-metal articulation have persistent or early recurrence of preoperative symptoms. Characteristic histological changes in the periprosthetic tissues suggested the development of an immunological response. Therefore, in order to determine the relevance of these symptoms, we performed a study of the clinical data and periprosthetic tissues associated with endoprostheses with a metal-on metal articulation that had been retrieved at revision. Methods: Periprosthetic tissues as well as the clinical data on the patients were obtained from the first nineteen consecutive revisions performed at the treating hospitals. At the time of the revision, fourteen patients had the metal-on-metal articulation exchanged for either an alumina-ceramic or a metal-on-polyethylene articulation. Five patients received another second-generation metal-on-metal total joint replacement. Five-micrometer sections were prepared from the tissue samples, were stained with routine and immunohistochemical methods, and were examined histologically. Histological specimens from three groups of patients, two of which were treated with non-metal-on-metal implants, served as controls. Results: The majority of patients had persistence of their preoperative pain or early recurrence of the pain after the original total hip replacement, and often a pronounced hip joint effusion had developed after the original replacement. Radiographic follow-up showed the development of radiolucent lines in five hips and of osteolysis in another seven hips. At the revision surgery, both the cup and the stem were found to be well fixed in nine patients. The characteristic histological features were diffuse and perivascular infiltrates of T and B lymphocytes and plasma cells, high endothelial venules, massive fibrin exudation, accumulation of macrophages with droplike inclusions, and infiltrates of eosinophilic granulocytes and necrosis. Only a few metal particles were detected. Immunohistochemical analysis demonstrated that the cellular reaction was still active. The patients who received another second-generation metal-on-metal articulation at the time of the revision had no decrease in symptoms. In the control group of tissues obtained at revisions of endoprostheses without cobalt, chromium, or nickel articulations, there were no similar signs of immune reactions. Conclusions: These histological findings support the possibility of a lymphocyte-dominated immunological response. Although the prevalence of this reaction is low, the persistence or early reappearance of symptoms, including a marked joint effusion and the development of osteolysis, after primary implantation may suggest the possibility of such a reaction.

1,172 citations


Journal ArticleDOI
TL;DR: There is limited and mixed high-level evidence to support the, albeit common, clinical use of these modalities and further research and scientific evaluation are required before biological solutions become realistic options.
Abstract: Tendon disorders are frequent and are responsible for substantial morbidity both in sports and in the workplace. Tendinopathy, as opposed to tendinitis or tendinosis, is the best generic descriptive term for the clinical conditions in and around tendons arising from overuse. Tendinopathy is a difficult problem requiring lengthy management, and patients often respond poorly to treatment. Preexisting degeneration has been implicated as a risk factor for acute tendon rupture. Several physical modalities have been developed to treat tendinopathy. There is limited and mixed high-level evidence to support the, albeit common, clinical use of these modalities. Further research and scientific evaluation are required before biological solutions become realistic options.

1,118 citations


Journal ArticleDOI
TL;DR: Total shoulder arthroplasty with the Delta III prosthesis is a salvage procedure for severe shoulder dysfunction caused by an irreparable rotator cuff tear associated with other glenohumeral lesions and has a substantial potential to improve the condition of patients with severe shoulders dysfunction, at least in the short term.
Abstract: Background: The Delta III reverse-ball-and-socket total shoulder implant is designed to restore overhead shoulder function in the presence of irreparable rotator cuff deficiency by using the intact deltoid muscle and the stability provided by the prosthetic design. Our purpose was to evaluate the clinical and radiographic results of this arthroplasty in a consecutive series of shoulders with painful pseudoparesis due to irreversible loss of rotator cuff function. Methods: Fifty-eight consecutive patients with moderate-to-severe shoulder pain and active anterior elevation of <90° due to an irreparable rotator cuff tear were treated with a Delta III total shoulder replacement at an average age of sixty-eight years. Seventeen of the procedures were the primary treatment for the shoulder, and forty-one were revisions. The patients were examined clinically and radiographically after an average duration of follow-up of thirty-eight months. Results: On the average, the subjective shoulder value increased from 18% preoperatively to 56% postoperatively (p < 0.0001); the relative Constant score, from 29% to 64% (p < 0.0001); the Constant score for pain, from 5.2 to 10.5 points (p < 0.0001); active anterior elevation, from 42° to 100° (p < 0.0001); and active abduction, from 43° to 90° (p < 0.0001). The patients for whom the implantation of the Delta III prosthesis was the primary procedure and those who had had previous surgery showed similar amounts of improvement. The total complication rate, including all minor complications, was 50%, and the reoperation rate was 33%. Of the seventeen primary operations, 47% (eight) were associated with a complication and 18% (three) were followed by a reoperation. Of the forty-one revisions, 51% (twenty-one) were associated with a complication and 39% (sixteen) were followed by a reoperation. Subjective results and satisfaction rates were not influenced by complications or reoperations when the prosthesis had been retained. Conclusions: Total shoulder arthroplasty with the Delta III prosthesis is a salvage procedure for severe shoulder dysfunction caused by an irreparable rotator cuff tear associated with other glenohumeral lesions. Complications were frequent following both primary and revision procedures, but they rarely affected the final outcome. The procedure has a substantial potential to improve the condition of patients with severe shoulder dysfunction, at least in the short term. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

958 citations


Journal ArticleDOI
TL;DR: The T9 sagittal offset, reflecting the sagittal balance of the spine, was dependent on three separate factors: a linear combination of the pelvic incidence, maximum lumbar lordosis, and sacral slope; the pelvic tilt; and the thoracic kyphosis.
Abstract: Background: There is an increasing recognition of the clinical importance of the sagittal plane alignment of the spine. A prospective study of several radiographic parameters of the sagittal profile of the spine was conducted to determine the physiological values of these parameters, to calculate th

943 citations


Journal ArticleDOI
TL;DR: Percutaneous autologous bone-marrow grafting is an effective and safe method for the treatment of an atrophic tibial diaphyseal nonunion, but the number of progenitors available in bone marrow aspirated from the iliac crest appears to be less than optimal in the absence of concentration.
Abstract: Background Bone marrow aspirated from the iliac crest contains progenitor cells that can be used to obtain bone-healing of nonunions. However, there is little available information regarding the number and concentration of these cells that are necessary to obtain bone repair. The purpose of this study was to evaluate the number and concentration of progenitor cells that were transplanted for the treatment of nonunion, the callus volume obtained after the transplantation, and the clinical healing rate. Methods Marrow was aspirated from both anterior iliac crests, concentrated on a cell separator, and then injected into sixty noninfected atrophic nonunions of the tibia. Each nonunion received a relatively constant volume of 20 cm(3) of concentrated bone marrow. The number of progenitor cells that was transplanted was estimated by counting the fibroblast colony-forming units. The volume of mineralized bone formation was determined by comparing preoperative computerized tomography scans with scans performed four months following the injection. Results The aspirates contained an average (and standard deviation) of 612 +/- 134 progenitors/cm(3) (range, 12 to 1224 progenitors/cm(3)) before concentration and an average of 2579 +/- 1121 progenitors/cm(3) (range, 60 to 6120 progenitors/cm(3)) after concentration. An average total of 51 x 10(3) fibroblast colony-forming units was injected into each nonunion. Bone union was obtained in fifty-three patients, and the bone marrow that had been injected into the nonunions of those patients contained >1500 progenitors/cm(3) and an average total of 54,962 +/- 17,431 progenitors. The concentration (634 +/- 187 progenitors/cm(3)) and the total number (19,324 +/- 6843) of progenitors injected into the nonunion sites of the seven patients in whom bone union was not obtained were both significantly lower (p = 0.001 and p Conclusions Percutaneous autologous bone-marrow grafting is an effective and safe method for the treatment of an atrophic tibial diaphyseal nonunion. However, its efficacy appears to be related to the number of progenitors in the graft, and the number of progenitors available in bone marrow aspirated from the iliac crest appears to be less than optimal in the absence of concentration.

853 citations


Journal ArticleDOI
TL;DR: The data from this study suggest that arthroplasty with the Reverse Shoulder Prosthesis may be a viable treatment for patients with glenohumeral arthritis and a massive rotator cuff tear, however, future studies will be necessary to determine the longevity of the implant and whether it will provide continued improvement in function.
Abstract: Patients who have pain and dysfunction from glenohumeral arthritis associated with severe rotator cuff deficiency have few treatment options The goal of this study was to retrospectively evaluate the short-term results of arthroplasty with use of the Reverse Shoulder Prosthesis in the management of this problem We report the results for sixty patients (sixty shoulders) with a rotator cuff deficiency and glenohumeral arthritis who were followed for a minimum of two years Thirty-five patients had no previous shoulder surgery, whereas twenty-three had had either an open or arthroscopic rotator cuff repair, one had had a subacromial decompression, and one had had a biceps tendon repair All patients were assessed preoperatively and postoperatively with the American Shoulder and Elbow Surgeons scoring system for pain and function and with visual analog scales for pain and function They were also asked to rate their satisfaction with the outcome The shoulder range of motion was measured preoperatively and postoperatively The average age of the patients was seventy-one years The average duration of follow-up was thirty-three months All measures improved significantly (p < 00001) The mean total score on the American Shoulder and Elbow Surgeons system improved from 343 to 682; the mean function score, from 161 to 294; and the mean pain score, from 182 to 387 The score for function on the visual analog scale improved from 27 to 60, and the score for pain on the visual analog scale improved from 63 to 22 Forward flexion increased from 550° to 1051°, and abduction increased from 414° to 1018° Forty-one of the sixty patients rated the outcome as good or excellent; sixteen were satisfied, and three were dissatisfied There were a total of thirteen complications in ten patients (17%) Seven patients (12%) had eight failures, requiring revision surgery to another Reverse Shoulder Prosthesis in five patients (one shoulder had two revisions) and revision to a hemiarthroplasty in two patients because of deep infection The data from this study suggest that arthroplasty with the Reverse Shoulder Prosthesis may be a viable treatment for patients with glenohumeral arthritis and a massive rotator cuff tear However, future studies will be necessary to determine the longevity of the implant and whether it will provide continued improvement in function Therapeutic Level IV See Instructions to Authors for a complete description of levels of evidence

773 citations


Journal Article
TL;DR: Investigation regarding the pathogenesis of posttraumatic osteoarthritis, the form of osteoartritis that develops following joint injury, is helping to explain the development and progression of joint degeneration.
Abstract: Articular cartilage, which makes possible the painless, low-friction movement of synovial joints, consists of a sparsely distributed population of highly specialized cells called chondrocytes that are embedded within a matrix and provide articular cartilage with remarkable mechanical properties. Chondrocytes form the tissue matrix macromolecular framework from three classes of molecules: collagens, proteoglycans, and noncollagenous proteins. The matrix protects the cells from injury resulting from normal joint use, determines the types and concentrations of molecules that reach the cells, acts as a mechanical signal transducer for the cells, and helps maintain the chondrocyte phenotype. Throughout life, articular cartilage undergoes internal remodeling as the cells replace matrix macromolecules lost through degradation. Aging decreases the ability of chondrocytes to maintain and restore articular cartilage and thereby increases the risk of degeneration of the articular cartilage surface. Progressive degeneration of articular cartilage leads to joint pain and dysfunction that is clinically identified as osteoarthritis. Investigation regarding the pathogenesis of posttraumatic osteoarthritis, the form of osteoarthritis that develops following joint injury, is helping to explain the development and progression of joint degeneration.

756 citations


Journal ArticleDOI
TL;DR: Mortality was not increased when the surgery was delayed up to four days for patients who were otherwise fit for hip fracture surgery, however, a delay of more than four days significantly increased mortality.
Abstract: Background: Hip fracture is associated with high mortality among the elderly. Most patients require surgery, but the timing of the operation remains controversial. Surgery within twenty-four hours after admission has been recommended, but evidence supporting this approach is lacking. The objective of this study was to determine whether a delay in surgery for hip fractures affects postoperative mortality among elderly patients. Methods: We conducted a prospective, observational study of 2660 patients who underwent surgical treatment of a hip fracture at one university hospital. We measured mortality rates following the surgery in relation to the delay in the surgery and the acute medical comorbidities on admission. Results: The mortality following the hip fracture surgery was 9% (246 of 2660) at thirty days, 19% at ninety days, and 30% at twelve months. Of the patients who had been declared fit for surgery, those operated on without delay had a thirty-day mortality of 8.7% and those for whom the surgery had been delayed between one and four days had a thirty-day mortality of 7.3%. This difference was not significant (p = 0.51). The thirty-day mortality for patients for whom the surgery had been delayed for more than four days was 10.7%, and this small group had significantly increased mortality at ninety days (hazard ratio = 2.25; p = 0.001) and one year (hazard ratio = 2.4; p = 0.001). Patients who had been admitted with an acute medical comorbidity that required treatment prior to the surgery had a thirty-day mortality of 17%, which was nearly 2.5 times greater than that for patients who had been initially considered fit for surgery (hazard ratio = 2.3, 95% confidence interval = 1.6 to 3.3; p < 0.001). Conclusions: The thirty-day mortality following surgery for a hip fracture was 9%. Patients with medical comorbidities that delayed surgery had 2.5 times the risk of death within thirty days after the surgery compared with patients without comorbidities that delayed surgery. Mortality was not increased when the surgery was delayed up to four days for patients who were otherwise fit for hip fracture surgery. However, a delay of more than four days significantly increased mortality. Level of Evidence: Therapeutic Level II. See Instructions to Authors for a complete description of levels of evidence.

Journal ArticleDOI
TL;DR: Microfracture repair of articular cartilage lesions in the knee results in significant functional improvement at a minimum follow-up of two years, and the best short-term results are observed with good fill grade, low body-mass index, and a short duration of preoperative symptoms.
Abstract: Background: Microfracture is a frequently used technique for the repair of articular cartilage lesions of the knee. Despite the popularity of the technique, prospective information about the clinical results after microfracture is still limited. The purpose of our study was to identify the factors that affect the clinical outcome from this cartilage repair technique. Methods: Forty-eight symptomatic patients with isolated full-thickness articular cartilage defects of the femur in a stable knee were treated with the microfracture technique. Prospective evaluation of patient outcome was performed for a minimum follow-up of twenty-four months with a combination of validated outcome scores, subjective clinical rating, and cartilage-sensitive magnetic resonance imaging. Results: At the time of the latest follow-up, knee function was rated good to excellent for thirty-two patients (67%), fair for twelve patients (25%), and poor for four (8%). Significant increases in the activities of daily living scores, International Knee Documentation Committee scores, and the physical component score of the Short Form-36 were demonstrated after microfracture (p 30 kg/m2. Significant improvement in the activities of daily living score was more frequent with a preoperative duration of symptoms of less than twelve months (p < 0.05). Magnetic resonance imaging in twenty-four knees demonstrated good repair-tissue fill in the defect in thirteen patients (54%), moderate fill in seven (29%), and poor fill in four patients (17%). The fill grade correlated with the knee function scores. All knees with good fill demonstrated improved knee function, whereas poor fill grade was associated with limited improvement and decreasing functional scores after twenty-four months. Conclusions: Microfracture repair of articular cartilage lesions in the knee results in significant functional improvement at a minimum follow-up of two years. The best short-term results are observed with good fill grade, low body-mass index, and a short duration of preoperative symptoms. A high body-mass index adversely affects short-term outcome, and a poor fill grade is associated with limited short-term durability. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Journal ArticleDOI
TL;DR: Hypertrophic lipping at the acromio-clavicular joint may impinge on the supraspinatus tendon when the arm is in abduction and, if the lip is prominent, this joint should be resected.
Abstract: Impingement on the tendinous portion of the rotator cuff by the coracoacromial ligament and the anterior third of the acromion is responsible for a characteristic syndrome of disability of the shoulder. A characteristic proliferative spur and ridge has been noted on the anterior lip and undersurface of the anterior process of the acromion and this area may also show erosion and eburnation. The treatment of the impingement is to remove the anterior edge and undersurface of the anterior part of the acromion with the attached coracoacromial ligament. The impingement may also involve the tendon of the long head of the biceps and if it does, it is best to decompress the tendon and remove any osteophytes which may be in its groove, but to avoid transplanting the biceps tendon if possible. Hypertrophic lipping at the acromio-clavicular joint may impinge on the supraspinatus tendon when the arm is in abduction and, if the lip is prominent, this joint should be resected. These are the principles of anterior acromioplasty.

Journal ArticleDOI
TL;DR: It is believed that the lack of incremental reimbursement associated with these procedures results in strong financial disincentives for physicians and hospitals to provide treatment for patients with an infection after a total hip arthroplasty.
Abstract: Background: Deep infection following total hip arthroplasty is a devastating complication for the patient and a costly one for patients, surgeons, hospitals, and payers. The purpose of this study was to compare revision total hip arthroplasty for infection, revision total hip arthroplasty for aseptic loosening, and primary total hip arthroplasty with respect to their impact on hospital and surgeon resource utilization and referral patterns to a tertiary-care hospital. Methods: Clinical, demographic, and economic data were obtained for twenty-five consecutive patients with an infection after a total hip replacement who underwent a two-stage revision arthroplasty (Group 1) performed by one of two surgeons, between March 2001 and December 2002, at a single institution. Similar data were collected during the same time-period for a cohort of twenty-five consecutive patients who underwent revision of both components because of aseptic loosening (Group 2) and twenty-five consecutive patients who underwent a primary hip arthroplasty (Group 3). Quantitative and categorical variables were compared among the groups. Referral patterns were examined by reviewing the primary diagnosis for all patients referred to our institution for a revision total hip arthroplasty during a five-year period. Results: Revision procedures for infection were associated with longer operative time, more blood loss, and a higher number of complications compared with revisions for aseptic loosening or primary total hip arthroplasty (p < 0.02 for all). Revisions for infection were also associated with a higher total number of hospitalizations, total number of days in the hospital, total number of operations, total hospital costs, total outpatient visits, and total outpatient charges during the twelve-month period following the index procedure (p < 0.001 for all). The incidence of referrals to our institution for a diagnosis of infection following total hip arthroplasty increased significantly over a five-year period (Spearman rank correlation, 1.0; p = 0.0083), while referral rates for revision for causes other than infection remained relatively constant (Spearman rank correlation, 0.500; p = 0.3910). Conclusions: The treatment of patients with an infection after a total hip arthroplasty is associated with significantly greater hospital and physician resource utilization compared with the treatment of patients who have a revision because of aseptic loosening or who have a primary total hip arthroplasty. We believe that the lack of incremental reimbursement associated with these procedures results in strong financial disincentives for physicians and hospitals to provide treatment for patients with an infection after a total hip arthroplasty.

Journal ArticleDOI
TL;DR: It appears that, compared with above-the-knee amputation or disarticulation of the hip, the use of a limb-salvage procedure for osteosarcoma of the distal end of the femur did not shorten the disease-free interval or compromise long-term survival.
Abstract: A retrospective multi-institutional study of 227 patients with osteosarcoma of the distal end of the femur was done to compare rates of local recurrence, metastasis, and survival. Three cohorts of patients who had had either a limb-sparing procedure, an above-the-knee amputation, or disarticulation of the hip were compared. The results revealed prevalences of eight of seventy-three, nine of 115, and zero of thirty-nine as to local recurrence; forty-three of seventy-three, sixty-five of 115, and twenty-one of thirty-nine as to metastasis; and thirty-three of seventy-three, forty-eight of 115, and eighteen of thirty-nine as to death. Of the seventeen patients who had a local recurrence, sixteen died. In the limb-salvage group, eighteen patients required amputation, because of local recurrence in eight and other local complications in ten. The Kaplan-Meier estimates of the percentage of patients who survived and the percentage of patients without recurrent disease showed no difference among the three surgical groups (Mantel-Cox test statistic: p = 0.8) after a median length of follow-up of five and one-half years. Various covariant adjusted estimates yielded similar results. For the entire group of patients, the rate of continuously disease-free survival was 42 per cent, and the over-all rate of survival was 55 per cent at five years. It appears that, compared with above-the-knee amputation or disarticulation of the hip, the use of a limb-salvage procedure for osteosarcoma of the distal end of the femur did not shorten the disease-free interval or compromise long-term survival.

Journal ArticleDOI
TL;DR: The histological appearance of periprosthetic tissues retrieved from around metal-on-metal and metal- on-polyethylene total hip replacements and compared these findings with the appearance of control tissues retrieved at the time of primary arthroplasty suggest that these findings may represent a novel mode of failure for some metal-On-metal joint replacements.
Abstract: Background: Metal-on-metal bearing surfaces have been reintroduced for use during total hip replacement To assess tissue reactions to various types of articulations, we studied the histological appearance of periprosthetic tissues retrieved from around metal-on-metal and metal-on-polyethylene total hip replacements and compared these findings with the appearance of control tissues retrieved at the time of primary arthroplasty Methods: Periprosthetic tissues were obtained at the time of revision of twenty-five cobalt chromium-on-cobalt chromium, nine cobalt chromium-on-polyethylene, and ten titanium-on-polyethylene total hip arthroplasties Control tissues were obtained from nine osteoarthritic hips at the time of primary total hip arthroplasty Each tissue sample was processed for routine histological analysis, and sections were stained with hematoxylin and eosin Quantitative stereological analysis was performed with use of light microscopy Results: Tissue samples obtained from hips with metal-on-metal implants displayed a pattern of well-demarcated tissue layers A prominent feature, seen in seventeen of twenty-five tissue samples, was a pattern of perivascular infiltration of lymphocytes In ten of the tissue samples obtained from hips with metal-on-metal prostheses, there was also an accumulation of plasma cells in association with macrophages that contained metallic wear-debris particles The surfaces of tissues obtained from hips with metal-on-metal prostheses were more ulcerated than those obtained from hips with other types of implants, particularly in the region immediately superficial to areas of perivascular lymphocytic infiltration The lymphocytic infiltration was more pronounced in samples obtained at the time of revision because of aseptic failure than in samples retrieved at the time of autopsy or during arthrotomy for reasons other than aseptic failure Total-joint-replacement and surface-replacement designs of metal-on-metal prostheses were associated with similar results Tissue samples obtained from hips with metal-on-polyethylene implants showed far less surface ulceration, much less distinction between tissue layers, no pattern of lymphocytic infiltration, and no plasma cells The inflammation was predominantly histiocytic Tissues retrieved from hips undergoing primary joint replacement showed dense scar tissue and minimal inflammation Conclusions and Clinical Relevance: The pattern and type of inflammation seen in periprosthetic tissues obtained from hips with metal-on-metal and metal-on-polyethylene implants are very different At the present time, we do not know the prevalence or clinical implications of these histologic findings, but we suggest that they may represent a novel mode of failure for some metal-on-metal joint replacements

Journal ArticleDOI
TL;DR: Use of the surgical protocol for elbow dislocations with associated radial head and coronoid fractures restored sufficient elbow stability to allow early motion postoperatively, enhancing the functional outcome.
Abstract: BACKGROUND: The results of elbow dislocations with associated radial head and coronoid fractures are often poor because of recurrent instability and stiffness from prolonged immobilization. We managed these injuries with a standard surgical protocol, postulating that early intervention, stable fixation, and repair would provide sufficient stability to allow motion at seven to ten days postoperatively and enhance functional outcome. METHODS: We retrospectively reviewed the results of this treatment performed, at two university-affiliated teaching hospitals, in thirty-six consecutive patients (thirty-six elbows) with an elbow dislocation and an associated fracture of both the radial head and the coronoid process. Our surgical protocol included fixation or replacement of the radial head, fixation of the coronoid fracture if possible, repair of associated capsular and lateral ligamentous injuries, and in selected cases repair of the medial collateral ligament and/or adjuvanthinged external fixation. Patients were evaluated both radiographically and with a clinical examination at the time of the latest follow-up. RESULTS: At a mean of thirty-four months postoperatively, the flexion-extension arc of the elbow averaged 112° ± 11° and forearm rotation averaged 136° ± 16°. The mean Mayo Elbow Performance Score was 88 points (range, 45 to 100 points), which corresponded to fifteen excellent results, thirteen good results, seven fair results, and one poor result. Concentric stability was restored to thirty-four elbows. Eight patients had complications requiring a reoperation: two had a synostosis; one, recurrent instability; four, hardware removal and elbow release; and one, a wound infection. CONCLUSIONS: Use of our surgical protocol for elbow dislocations with associated radial head and coronoid fractures restored sufficient elbow stability to allow early motion postoperatively, enhancing the functional outcome. We recommend early operative repair with a standard protocol for these injuries.

Journal ArticleDOI
TL;DR: In total hip arthroplasty, a larger femoral head diameter was associated with a lower long-term cumulative risk of dislocation and was greatest in association with the posterolateral approach.
Abstract: Background: It has been postulated that use of a larger femoral head could reduce the risk of dislocation after total hip arthroplasty, but only limited clinical data have been presented as proof of this hypothesis Methods: From 1969 to 1999, 21,047 primary total hip arthroplasties with varying femoral head sizes were performed at one institution Patients routinely were followed at defined intervals and were specifically queried about dislocation The operative approach was anterolateral in 9155 arthroplasties, posterolateral in 3646, and transtrochanteric in 8246 The femoral head diameter was 22 mm in 8691 of the procedures, 28 mm in 8797, and 32 mm in 3559 Results: One or more dislocations occurred in 868 of the 21,047 hips The cumulative risk of first-time dislocation was 22% at one year, 30% at five years, 38% at ten years, and 60% at twenty years The cumulative ten-year rate of dislocation was 31% following anterolateral approaches, 34% following transtrochanteric approaches, and 69% following posterolateral approaches The cumulative ten-year rate of dislocation was 38% for 22-mm-diameter femoral heads, 30% for 28-mm heads, and 24% for 32-mm heads in hips treated with an anterolateral approach; 35% for 22-mm heads, 35% for 28-mm heads, and 28% for 32-mm heads in hips treated with a transtrochanteric approach; and 121% for 22-mm heads, 69% for 28-mm heads, and 38% for 32-mm heads in hips treated with a posterolateral approach Multivariate analysis showed the relative risk of dislocation to be 17 for 22-mm compared with 32-mm heads and 13 for 28-mm compared with 32-mm heads Conclusions: In total hip arthroplasty, a larger femoral head diameter was associated with a lower long-term cumulative risk of dislocation The femoral head diameter had an effect in association with all operative approaches, but the effect was greatest in association with the posterolateral approach Level of Evidence: Therapeutic Level III See Instructions to Authors for a complete description of levels of evidence

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TL;DR: Open operative treatment of acute Achilles tendon ruptures significantly reduces the risk of rerupture compared with nonoperative treatment, but operative treatment is associated with a significantly higher risk of other complications.
Abstract: To The Editor: Our article “Treatment of Acute Achilles Tendon Ruptures. A Meta-Analysis of Randomized, Controlled Trials” (2005; 87:2202-10), by Khan et al., was based …

Journal ArticleDOI
TL;DR: Bisphosphonate therapy may help to improve function, decrease pain, and lower fracture risk in appropriately selected patients with fibrous dysplasia.
Abstract: Fibrous dysplasia is a common benign skeletal lesion that may involve one bone (monostotic) or multiple bones (polyostotic) and occurs throughout the skeleton with a predilection for the long bones, ribs, and craniofacial bones. The etiology of fibrous dysplasia has been linked to an activating mutation in the gene that encodes the alpha subunit of stimulatory G protein (G(s)alpha) located at 20q13.2-13.3. Most lesions are monostotic, asymptomatic, and identified incidentally and can be treated with clinical observation and patient education. Bisphosphonate therapy may help to improve function, decrease pain, and lower fracture risk in appropriately selected patients with fibrous dysplasia. Surgery is indicated for confirmatory biopsy, correction of deformity, prevention of pathologic fracture, and/or eradication of symptomatic lesions. The use of cortical grafts is preferred over cancellous grafts or bone-graft substitutes because of the superior physical qualities of remodeled cortical bone.

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TL;DR: While surgeons prefer internal fixation for younger patients and arthroplasty for older patients, they disagree about the optimal approach to the management of patients between sixty and eighty years old with a displaced fracture and active patients with a Garden type-III fracture.
Abstract: Background: Hip fractures occur in 280,000 North Americans each year. Although surgeons have reached consensus with regard to the treatment of undisplaced fractures of the hip, the surgical treatment of displaced fractures remains controversial. Identifying surgeons' preferences in techniques, and the rationale for their choices, may aid in focusing educational activities to the orthopaedic community as well as planning future clinical trials. Our objective was to clarify current opinion with regard to the operative treatment of displaced fractures of the femoral neck. Methods: We used a cross-sectional survey design and a sample-to-redundancy strategy to examine surgeons' preferences in the treatment of displaced femoral neck fractures. We mailed this survey to members of the Orthopaedic Trauma Association and European-AO International-affiliated trauma centers. Results: Of 442 surgeons who received the questionnaire, 298 (67%) responded. The typical respondent was a North American man over the age of forty years who was in academic practice, supervised residents, had fellowship training in trauma, and worked in a low-volume center (<100 hip fractures per year), treating an equal proportion of displaced and undisplaced femoral neck fractures. Most surgeons believed that internal fixation was the procedure of choice in younger patients (those who are less than sixty years old) with a displaced fracture (Garden type III or IV). For patients over eighty years old with Garden type-III or IV fractures, almost all surgeons preferred arthroplasty. Respondents varied widely in their preferences for the treatment of patients who were sixty to eighty years old with a displaced fracture (Garden type III or IV) or active patients with a Garden type-III fracture. Many surgeons believed there was no difference between arthroplasty and internal fixation when considering mortality (45%), infection rates (30%), and quality of life (37%). Surgeons also revealed variable preferences in their choice of the optimal approach to arthroplasty for patients between sixty and eighty years old with a type-IV fracture (32% preferred unipolar; 41%, bipolar; and 17%, total hip arthroplasty) and in the optimal choice of implant for internal fixation. Conclusions: While surgeons prefer internal fixation for younger patients and arthroplasty for older patients, they disagree about the optimal approach to the management of patients between sixty and eighty years old with a displaced fracture and active patients with a Garden type-III fracture. Surgeons also disagree on the optimal implants for internal fixation or arthroplasty.

Journal ArticleDOI
TL;DR: Patients who are managed with total knee arthroplasty have profound impairment of quadriceps strength one month after surgery, predominantly due to failure of voluntary muscle activation, and it is also influenced, to a lesser degree, by muscle atrophy.
Abstract: Background: While total knee arthroplasty reduces pain and provides a functional range of motion of the knee, quadriceps weakness and reduced functional capacity typically are still present one year after surgery. The purpose of the present investigation was to determine the role of failure of voluntary muscle activation and muscle atrophy in the early loss of quadriceps strength after surgery. Methods: Twenty patients with unilateral knee osteoarthritis were tested an average of ten days before and twentyseven days after primary total knee arthroplasty. Quadriceps strength and voluntary muscle activation were measured with use of a burst-superimposition technique in which a supramaximal burst of electrical stimulation is superimposed on a maximum voluntary isometric contraction. Maximal quadriceps cross-sectional area was assessed with use of magnetic resonance imaging. Results: Postoperatively, quadriceps strength was decreased by 62%, voluntary activation was decreased by 17%, and maximal cross-sectional area was decreased by 10% in comparison with the preoperative values; these differences were significant (p < 0.01). Collectively, failure of voluntary muscle activation and atrophy explained 85% of the loss of quadriceps strength (p < 0.001). Multiple linear regression analysis revealed that failure of voluntary activation contributed nearly twice as much as atrophy did to the loss of quadriceps strength. The severity of knee pain with muscle contraction did not change significantly compared with the preoperative level (p = 0.31). Changes in knee pain during strength-testing did not account for a significant amount of the change in voluntary activation (p = 0.14). Conclusions: Patients who are managed with total knee arthroplasty have profound impairment of quadriceps strength one month after surgery. This impairment is predominantly due to failure of voluntary muscle activation, and it is also influenced, to a lesser degree, by muscle atrophy. Knee pain with muscle contraction played a surprisingly small role in the reduction of muscle activation.

Journal ArticleDOI
TL;DR: The combination of the Hawkins-Kennedy impingement sign, the painful arc sign, and the infraspinatus muscle test yielded the best post-test probability for any degree of impingements syndrome, including full-thickness rotator cuff tears.
Abstract: BackgroundSeveral tests for making the diagnosis of rotator cuff disease have been described, but their utility for diagnosing bursitis alone, partial-thickness rotator cuff tears, and full-thickness rotator cuff tears has not been studied. The hypothesis of this study was that the degree of severit

Journal ArticleDOI
TL;DR: In this article, the authors describe the minimum ten-year results associated with a unicompartmental knee arthroplasty design that is in current use, and show that after a minimum duration of follow-up of ten years, this cemented modular knee design was associated with excellent clinical and radiographic results.
Abstract: Background: There is a renewed interest in unicompartmental knee arthroplasty. The present report describes the minimum ten-year results associated with a unicompartmental knee arthroplasty design that is in current use. Methods: Sixty-two consecutive unicompartmental knee arthroplasties that were performed with cemented modular Miller-Galante implants in fifty-one patients were studied prospectively both clinically and radiographically. All patients had isolated unicompartmental disease without patellofemoral symptoms. No patient was lost to follow-up. Thirteen patients (thirteen knees) died after less than ten years of follow-up, leaving thirty-eight patients (forty-nine knees) with a minimum of ten years of follow-up. The average duration of follow-up was twelve years. Results: The mean Hospital for Special Surgery knee score improved from 55 points preoperatively to 92 points at the time of the final follow-up. Thirty-nine knees (80%) had an excellent result, six (12%) had a good result, and four (8%) had a fair result. At the time of the final follow-up, thirty-nine knees (80%) had flexion to at least 120°. Two patients (two knees) with well-fixed components underwent revision to total knee arthroplasty, at seven and eleven years, because of progression of patellofemoral arthritis. At the time of the final follow-up, no component was loose radiographically and there was no evidence of periprosthetic osteolysis. Radiographic evidence of progressive loss of joint space was observed in the opposite compartment of nine knees (18%) and in the patellofemoral space of seven knees (14%). Kaplan-Meier analysis revealed a survival rate of 98.0% ± 2.0% at ten years and of 95.7% ± 4.3% at thirteen years, with revision or radiographic loosening as the end point. The survival rate was 100% at thirteen years with aseptic loosening as the end point. Conclusions: After a minimum duration of follow-up of ten years, this cemented modular unicompartmental knee design was associated with excellent clinical and radiographic results. Although the ten-year survival rate was excellent, radiographic signs of progression of osteoarthritis in the other compartments continued at a slow rate. With appropriate indications and technique, this unicompartmental knee design can yield excellent results into the beginning of the second decade of use. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

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TL;DR: Minimally invasive total hip arthroplasty performed through a single-incision posterior approach by a high-volume hip surgeon with extensive experience in less invasive approaches to the hip is safe and reproducible, however, it offers no significant benefit in the early postoperative period compared with a standard incision.
Abstract: Background: Minimally invasive total hip arthroplasty has stirred substantial controversy with regard to whether it provides superior outcomes compared with total hip arthroplasty performed through longer incisions The orthopaedic literature is deficient in well-designed scientific studies to support the clinical superiority of this approach The objective of this study was to compare the results of a single mini-incision approach with those of a standard-incision total hip arthroplasty in the early postoperative period Methods: Two hundred and nineteen patients (219 hips) admitted for unilateral total hip arthroplasty between December 2003 and June 2004 were randomized to undergo surgery through a short incision of ≤10 cm or a standard incision of 16 cm All patients were blinded to the size of the incision for the duration of the hospital stay The anesthetic, analgesic, and postoperative physiotherapy protocols were standardized, with the staff also blinded to the technique used A single surgeon, who had performed more than 300 short-incision hip replacements prior to the start of this study and who performs an average of 415 primary total hip replacements a year, performed all procedures through a single-incision posterior approach using a cementless cup and cemented stem Results: The two groups were matched for age, grade according to the system of the American Society of Anesthesiologists, and body mass index No significant difference was detected with respect to postoperative hematocrit, blood transfusion requirements, pain scores, or analgesic use We found no difference in early walking ability or length of hospital stay and no difference in component placement, cement-mantle quality, or functional outcome scores at six weeks The patient variables significantly associated with a probability of early discharge independent of incision length were patient age and preoperative hemoglobin levels (p < 005) The surgical scars contracted significantly over six weeks (p < 005) but by a similar proportion of 11% to 12% in both groups Conclusions: Minimally invasive total hip arthroplasty performed through a single-incision posterior approach by a high-volume hip surgeon with extensive experience in less invasive approaches to the hip is safe and reproducible However, it offers no significant benefit in the early postoperative period compared with a standard incision of 16 cm As it is not known whether lower-volume and less-experienced surgeons can achieve similar results, the mini-incision technique merits further study before wide dissemination and implementation of this family of surgical approaches can be recommended Level of Evidence: Therapeutic Level I See Instructions to Authors for a complete description of levels of evidence

Journal ArticleDOI
TL;DR: Overall, the rates of postoperative complications during the ninety days following total knee replacement are low, and in the United States, blacks and individuals with low income undergo total knee Replacement less frequently and generally have higher rates of adverse outcomes following primary knee replacement.
Abstract: Background: There are limited population-based data on the utilization and outcomes of total knee replacement. The aim of the present study was to describe the rates of primary and revision total knee replacement and selected outcomes in persons older than sixty-five years of age in the United States. Methods: Using Medicare claims, we computed annual incidence rates of unilateral elective primary and revision total knee replacement among United States Medicare beneficiaries in the year 2000. Poisson regression was used to assess the relationships between demographic characteristics and the incidence rates of primary and revision knee replacement. Proportional hazards models were used to examine the relationships between the ninety-day rates of complications and demographic and clinical factors. Results: The rate of primary knee replacement was lower in blacks than in whites and in those qualifying for Medicaid supplementation than in those with higher incomes. The complications observed during the ninety days following primary knee replacement included mortality (0.7%), readmission (0.9%), pulmonary embolus (0.8%), wound infection (0.4%), pneumonia (1.4%), and myocardial infarction (0.8%). The complications observed during the ninety days following revision knee replacement were mortality (1.1%), readmission (4.7%), pulmonary embolus (0.5%), wound infection (1.8%), pneumonia (1.4%), and myocardial infarction (1.0%). Blacks had higher rates of mortality, readmission, and wound infection after primary knee replacement than whites did. Patients who qualified for Medicaid supplementation had higher complication rates, particularly after primary knee replacement. Conclusions: Overall, the rates of postoperative complications during the ninety days following total knee replacement are low. In the United States, blacks and individuals with low income undergo total knee replacement less frequently and generally have higher rates of adverse outcomes following primary knee replacement. Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.

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TL;DR: The results confirm previous conclusions that reconstruction for the treatment of injuries below the distal part of the femur typically results in functional outcomes equivalent to those of amputation.
Abstract: Background: A recent study demonstrated that patients treated with amputation and those treated with reconstruction had comparable functional outcomes at two years following limb-threatening trauma. The present study was designed to determine whether those outcomes improved after two years, and whether differences according to the type of treatment emerged. Methods: Three hundred and ninety-seven patients who had undergone amputation or reconstruction of the lower extremity were interviewed by telephone at an average of eighty-four months after the injury. Functional outcomes were assessed with use of the physical and psychosocial subscores of the Sickness Impact Profile (SIP) and were compared with similar scores obtained at twenty-four months. Results: On the average, physical and psychosocial functioning deteriorated between twenty-four and eighty-four months after the injury. At eighty-four months, one-half of the patients had a physical SIP subscore of ≥10 points, which is indicative of substantial disability, and only 34.5% had a score typical of a general population of similar age and gender. There were few significant differences in the outcomes according to the type of treatment, with two exceptions. Compared with patients treated with reconstruction for a tibial shaft fracture, those with only a severe soft-tissue injury of the leg were 3.1 times more likely to have a physical SIP subscore of 5 points (p < 0.05) and those treated with a through-the-knee amputation were 11.5 times more likely to have a physical subscore of 5 points (p < 0.05). There were no significant differences in the psychosocial outcomes according to treatment group. Patient characteristics that were significantly associated with poorer outcomes included older age, female gender, nonwhite race, lower education level, living in a poor household, current or previous smoking, low self-efficacy, poor self-reported health status before the injury, and involvement with the legal system in an effort to obtain disability payments. Except for age, predictors of poor outcome were similar at twenty-four and eighty-four months after the injury. Conclusions: The results confirm previous conclusions that reconstruction for the treatment of injuries below the distal part of the femur typically results in functional outcomes equivalent to those of amputation. Regardless of the treatment option, however, long-term functional outcomes are poor. Priority should be given to efforts to improve post-acute-care services that address secondary conditions that compromise optimal recovery. Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.

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TL;DR: Alendronate appeared to prevent early collapse of the femoral head in the hips with Steinberg stage-II or IIIC nontraumatic osteonecrosis, and a longer duration of follow-up is needed to confirm whether alendronsate prevents or only retards collapse.
Abstract: Background: Osteonecrosis of the femoral head is the most common diagnosis leading to total hip arthroplasty in young adults. Joint-preserving treatment options have been mainly surgical, with inconsistent results. Alendronate (a bisphosphonate agent) has been shown to lower the prevalence of vertebral compression fractures and could potentially retard the collapse of an osteonecrotic femoral head. The purpose of this study was to test the effect of alendronate in preventing early collapse of the femoral head in patients with nontraumatic osteonecrosis. Methods: Forty patients with Steinberg stage-II or III nontraumatic osteonecrosis of the femoral head and a necrotic area of >30% (class C) were randomly divided into alendronate and control groups of twenty patients each. Patients in the alendronate group took 70 mg of alendronate orally per week for twenty-five weeks, while the patients in the control group did not receive this medication or a placebo. The patients were observed for a minimum of twenty-four months. Harris hip scores, plain radiographs, and magnetic resonance imaging scans were obtained. Results: During the study period, only two of twenty-nine femoral heads in the alendronate group collapsed, whereas nineteen of twenty-five femoral heads in the control group collapsed (p < 0.001). One hip in the alendronate group underwent total hip arthroplasty, whereas sixteen hips in the control group underwent total hip arthroplasty (p < 0.001). Conclusions: Alendronate appeared to prevent early collapse of the femoral head in the hips with Steinberg stage-II or IIIC nontraumatic osteonecrosis. A longer duration of follow-up is needed to confirm whether alendronate prevents or only retards collapse. Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

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TL;DR: New studies relate the morphology of the femur (condyles and epicondyles) and the axis of the limb (mechanical axis) to the location and orientation of the flexion-extension axis ofThe knee in three-dimensional space.
Abstract: T he premise of this article, and the scientific exhibit upon which it is based, is that the morphologic shape of the distal aspect of the femur and its relation to the tibia and the patella dictates the kinematics of the knee. The morphologic and kinematic characteristics of the knee presented in earlier exhibits1,2 at the 2001 and 2003 Annual Meetings of the American Academy of Orthopaedic Surgeons demonstrated the following relationships. The location and orientation of the femoral sulcus is lateral to the midplane between the femoral condyles and is oriented between the anatomic and mechanical axes of the femur (Figs. 1-A and 1-B). The center of the femur in cross section is offset, medial and anterior, to the center of the tibia, and these offset cross sections are rotated relative to each other in the pathologic knee (Fig. 2). A single, fixed flexion-extension axis of the knee is centered in the asymmetric cylindrical femoral condyles (Fig. 3). These and other observations1-8 of distal femoral morphology and their relationship to knee kinematics form the basis for the additional studies in the present article. These new studies relate the morphology of the femur (condyles and epicondyles) and the axis of the limb (mechanical axis) to the location and orientation of the flexion-extension axis of the knee in three-dimensional space. The clinical importance of this work is found in its application to ligament reconstruction and total knee arthroplasty. Despite improvements in design, implant alignment in total knee arthroplasty remains a crucial factor in the function and longevity of the implant9-11. It has been demonstrated that malalignment causes increased wear of the implant and premature failure of the construct11-14. Most contemporary implants are designed to be aligned to …

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TL;DR: Surgical treatment of the knee dislocations in this series provided satisfactory subjective and objective outcomes at two to six years postoperatively, however, the ability of patients to return to high-demand sports and strenuous manual labor was less predictable.
Abstract: BACKGROUND: The evaluation and management of knee dislocations remain variable and controversial. The purpose of this study was to describe our method of surgical treatment of knee dislocations with use of a standardized protocol and to report the clinical results. METHODS: Forty-seven consecutive patients presented with an occult (reduced) or grossly dislocated knee. Fourteen of these patients were not included in this series because of confounding variables: four had an open knee dislocation, five had vascular injury requiring repair, three were treated with external fixation, and two had associated injury. The remaining thirty-three patients underwent surgical treatment for the knee dislocation with our standard approach. Anatomical repair and/or replacement was performed with fresh-frozen allograft tissue. Thirty-one of the thirty-three patients returned for subjective and objective evaluation with use of four different knee-rating scales at a minimum of twenty-four months after the operation. RESULTS: Nineteen of the thirty-one patients were treated acutely (less than three weeks after the injury) and twelve, chronically. The mean Lysholm score was 91 points for the acutely reconstructed knees and 80 points for the chronically reconstructed knees. The Knee Outcome Survey Activities of Daily Living scores averaged 91 points for the acutely reconstructed knees and 84 points for the chronically reconstructed knees. The Knee Outcome Survey Sports Activity scores averaged 89 points for the acutely reconstructed knees and 69 points for the chronically reconstructed knees. According to the Meyers ratings, twenty-three patients had an excellent or good score and eight had a fair or poor score. Sixteen of the nineteen acutely reconstructed knees and seven of the twelve chronically reconstructed knees were given an excellent or good Meyers score. The average loss of extension was 1°, and the average loss of flexion was 12°. There was no difference in the range of motion between the acutely and chronically treated patients. Four acutely reconstructed knees required manipulation because of loss of flexion. Laxity tests demonstrated consistently improved stability in all patients, with more predictable results in the acutely treated patients. CONCLUSIONS: Surgical treatment of the knee dislocations in our series provided satisfactory subjective and objective outcomes at two to six years postoperatively. The patients who were treated acutely had higher subjective scores and better objective restoration of knee stability than did patients treated three weeks or more after the injury. Nearly all patients were able to perform daily activities with few problems. However, the ability of patients to return to high-demand sports and strenuous manual labor was less predictable.