Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ARTHROPLASTY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,675 records · Page 93Linked to original sources

The influence of rotator cuff disease on the results of shoulder arthroplasty for primary osteoarthritis: results of a multicenter study.

BACKGROUND: Rotator cuff disease is uncommon in primary glenohumeral osteoarthritis. Consequently, the prognostic implications of rotator cuff disease in patients undergoing prosthetic replacement for the treatment of primary glenohumeral osteoarthritis are uncertain. The purpose of this study was to report the effects of the condition of the supraspinatus tendon and the rotator cuff musculature on the results of shoulder arthroplasty in the treatment of primary osteoarthritis. METHODS: Five hundred and fifty-five shoulders in 514 patients who had an arthroplasty for the treatment of primary glenohumeral osteoarthritis as part of a multicenter study were evaluated. Forty-one shoulders had a partial-thickness tear of the supraspinatus, and forty-two had a full-thickness tear. Ninety shoulders had moderate (stage-2) fatty degeneration of the infraspinatus, and nineteen had severe (stage-3 or 4) degeneration. Eighty-four shoulders had moderate fatty degeneration of the subscapularis, and fifteen had severe degeneration. The influence of the condition of the supraspinatus tendon and the infraspinatus and subscapularis musculature on the postoperative outcome was evaluated with respect to the scores according to the system of Constant and Murley, active mobility, subjective satisfaction, radiographic result, and rate of complications. RESULTS: The shoulders were evaluated at a mean of 43.1 months postoperatively. With the numbers available, supraspinatus tears were not found to influence the postoperative outcome with respect to the total Constant score, active mobility, subjective satisfaction, radiographic result, or rate of complications. Additionally, the treatment of these tears did not markedly influence the outcome parameters. Conversely, both shoulders with moderate fatty degeneration and those with severe degeneration of the infraspinatus were associated with poorer results than those with no degeneration with respect to the total Constant score (p < 0.0005), active external rotation (p < 0.0005), active forward flexion (p = 0.001), and subjective satisfaction (p = 0.031). Similar although less dramatic results were seen with fatty degeneration of the subscapularis. CONCLUSIONS: This study demonstrates that minimally retracted or nonretracted rotator cuff tears that are limited to the supraspinatus tendon do not appreciably affect most shoulder-specific outcome parameters in shoulder arthroplasty performed for the treatment of primary osteoarthritis. Conversely, fatty degeneration of the infraspinatus and, less importantly, subscapularis musculature adversely affects many of these parameters.

Adult↗

Patellar resurfacing in total knee arthroplasty. A prospective, randomized study.

BACKGROUND: Anterior knee pain following total knee arthroplasty is a common complaint and typically is attributed to the patellofemoral joint. The purpose of the present study was to compare the outcome of resurfacing and nonresurfacing of the patella, particularly with regard to anterior knee pain, and to clarify the indications for patellar resurfacing at the time of total knee arthroplasty. METHODS: We performed a prospective, randomized study of 514 consecutive primary press-fit condylar total knee replacements. The patients were randomized to either resurfacing or retention of the patella. They were also randomized to either a cruciate-substituting or a cruciate-retaining prosthesis as part of a separate trial. The mean duration of follow-up was 5.3 years (range, two to 8.5 years), and the patients were assessed with use of the Knee Society rating, a clinical anterior knee pain score, and the British Orthopaedic Association patient-satisfaction score. The assessment was performed without the examiner knowing whether the patella had been resurfaced. At the time of follow-up, there were 474 knees. Thirty-five patients who had a bilateral knee replacement underwent resurfacing on one side only. RESULTS: The overall prevalence of anterior knee pain was 25.1% (fifty-eight of 231 knees) in the nonresurfacing group, compared with 5.3% (thirteen of 243 knees) in the resurfacing group (p < 0.0001). There was one case of component loosening. Ten of eleven patients who underwent secondary resurfacing had complete relief of anterior knee pain. The overall postoperative knee scores were lower in the nonresurfacing group, and the difference was significant among patients with osteoarthritis (p < 0.01). There was no significant difference between the resurfacing and nonresurfacing groups with regard to the postoperative function score. Patients who had a bilateral knee replacement were more likely to prefer the resurfaced side. CONCLUSIONS: As the present study showed a significantly higher rate of anterior knee pain following arthroplasty without patellar resurfacing, we recommend patellar resurfacing at the time of total knee replacement when technically possible.

Adult↗

Total hip arthroplasty with use of the cementless Zweymüller Alloclassic system. A ten to thirteen-year follow-up study.

BACKGROUND: The Zweymüller Alloclassic total hip arthroplasty system is widely used, although few intermediate-term studies have been published. The purpose of the present study was to evaluate the clinical and radiographic results of this system after ten years. METHODS: One hundred and twenty-four consecutive primary total hip arthroplasties were performed with the Zweymüller Alloclassic cementless system at our institution between February 1988 and March 1991, and 104 hips (ninety-four patients) were retrospectively reviewed after a minimum duration of follow-up of ten years. The mean age of the patients at the time of the arthroplasty was 62.3 years (range, twenty-five to seventy-seven years). The mean duration of follow-up was 11.3 years. Standard radiographs were made for all patients immediately after the operation, at six and twelve months, and annually thereafter for at least ten years. Cox multivariate regression analysis was performed to assess the influence of various factors on survival of the implant. RESULTS: The cumulative probability of not having a revision of any prosthetic component for any reason was 94.1% (95% confidence interval, 91.9% to 96.3%) at twelve years in the best-case scenario and 85.3% (95% confidence interval, 82.1% to 88.5%) at twelve years in the worst-case scenario for the entire series of 124 hips. Among the 104 hips in the follow-up study, three acetabular components and no stems were revised. Two hips had level-4 pain according to the system of Merle D'Aubigné and Postel. Seven acetabular components (7%) were loose at twelve years, and all stems had radiographic evidence of stable fixation. Acetabular cup loosening was related to a vertical cup angle (p = 0.0008, Student t test), acetabular wear of > or =1 mm (p = 0.001, Fisher exact test), and a 32-mm femoral head (p = 0.001, Fisher exact test). Although femoral osteolysis was seen in eighteen hips (17%) at twelve years, all osteolytic cavities were proximal and focal. CONCLUSIONS: The Zweymüller Alloclassic prosthesis, particularly its femoral stem, demonstrated good results and durable fixation at a minimum of ten years of follow-up.

Arthroplasty, Replacement, Hip↗

Effect of humeral condylar resection on strength and functional outcome after semiconstrained total elbow arthroplasty.

BACKGROUND: Under certain conditions it is standard practice to excise ununited humeral condyles during insertion of a semiconstrained total elbow prosthesis. Since the osseous origins of the common extensors and flexor-pronator muscles are lost, it has been postulated that this excision has a negative effect on strength. We are not aware of any previous study in which this issue has been investigated with use of standardized, objective testing of muscle strength. METHODS: We used objective testing to determine the effect of condylar resection on the muscle strength of the elbow, forearm, wrist, and hand in thirty-two patients who had undergone total elbow arthroplasty. To eliminate bias, the normal, contralateral limb served as the control, and all strength values are given as a percentage of the normal side. The humeral condyles were intact in sixteen patients and had been resected in the other sixteen. Patient demographics were similar in the two groups. RESULTS: There were no significant differences between the two groups with regard to strength of pronation (103% of the normal side in the group with intact condyles compared with 89% in the group with resection of the condyles; p = 0.40), supination (68% compared with 89%; p = 0.49), wrist flexion (66% compared with 56%; p = 0.46), wrist extension (75% compared with 65%; p = 0.40), or grip strength (83% compared with 72%; p = 0.40). There was also no difference between the two groups with regard to the Mayo Elbow Performance Score (79 points in the group with intact condyles compared with 77 points in the group with resection of the condyles; p = 0.67). CONCLUSIONS: Condylar resection has a minimal, clinically irrelevant effect on forearm, wrist, and hand strength and no effect on the Mayo Elbow Performance Score following total elbow arthroplasty. Thus, the findings of our study support the practice of condylar resection, which simplifies total elbow arthroplasty for many conditions.

Activities of Daily Living↗

Twenty-five-year results after Charnley total hip arthroplasty in patients less than fifty years old: a concise follow-up of a previous report.

We report the updated results for a previously evaluated cohort of patients who were less than fifty years old when they underwent Charnley total hip arthroplasty with cement. The original cohort consisted of ninety-three total hip arthroplasties performed in sixty-nine patients. The patients were followed for a minimum of twenty-five years after surgery or until death. The present report describes the findings of the radiographic and functional follow-up, which was performed for forty-two of the forty-three living patients. At the time of the latest follow-up, twenty-nine (31%) of the ninety-three total hip replacements had been revised or removed. Eighteen acetabular and five femoral components were revised secondary to aseptic loosening. The combined prevalence of radiographic failure or revision because of aseptic loosening was 13% for the femoral components and 34% for the acetabular components. Comorbid medical conditions significantly hindered results on each functional subscale (p < 0.05). This study demonstrates the durability of cemented total hip replacements in a young patient population. Sixty-nine percent of the original hip replacements were functioning well at the latest follow-up examination or at the time of death, and only 5% required more than one revision arthroplasty.

Adolescent↗

Results of porous-coated anatomic total hip arthroplasty without cement at fifteen years: a concise follow-up of a previous report.

The purpose of this study was to update the results of a prospective series of primary cementless total hip arthroplasties after a minimum of fifteen years of follow-up. It is one of the first studies of cementless total hip arthroplasties followed for a minimum of fifteen years. One hundred consecutive Porous Coated Anatomic (PCA) total hip replacements were implanted between October 1983 and January 1986. Fifty-five patients (sixty-four hips) that were alive at a minimum of fifteen years postoperatively are the focus of the present study. At this time of follow-up, at an average of 15.6 years (range, fifteen to seventeen years) after the total hip arthroplasty, 17% (seventeen hips) of the entire cohort and 23% (fifteen hips) of the living cohort had undergone revision because of loosening of the acetabular component or osteolysis. Seven percent (seven hips) of the entire cohort and 6% (four hips) of the living cohort had undergone revision for loosening of the femoral component or osteolysis. Only four femoral stems had been revised for isolated loosening (without osteolysis). The PCA femoral component proved to be durable at a minimum of fifteen years postoperatively, while the acetabular component was less durable.

Adult↗

The use of a constrained acetabular component to treat instability after total hip arthroplasty.

BACKGROUND: Recurrent dislocation after total hip arthroplasty is a disabling complication that can be difficult to treat and may not be amenable to nonoperative management. The purpose of the present study was to evaluate the clinical and radiographic outcome associated with the use of a constrained acetabular component as a salvage treatment for instability after hip arthroplasty. METHODS: We retrospectively reviewed the clinical and radiographic outcome of 110 arthroplasties, in 109 patients, that had been performed with use of a single design of constrained acetabular component. In seventy-nine hips the constrained component was implanted for the treatment of recurrent instability, and in thirty-one hips it was implanted because of absent or grossly deficient soft-tissue attachments that were believed to be associated with a high risk for subsequent instability. RESULTS: The constrained acetabular device eliminated or prevented hip instability in all patients except two, who continued to have sensations of subluxation. The mean Harris hip score improved significantly, from 62.7 points preoperatively to 76.4 points at the time of the latest follow-up (p < 0.0001). There were no instances of dislocation or disassembly of the hip components. Radiographic analysis revealed radiolucent lines around the cup in fifteen hips (14%). There was a total of nine revisions: six for deep infection, two for acetabular component loosening, and one for a periprosthetic fracture of the femur. CONCLUSIONS: A constrained acetabular component reliably restores and maintains hip stability in patients with recalcitrant recurrent instability and can dependably prevent dislocation in those who are at high risk because of absent or deficient soft tissues about the hip. However, because of the early appearance of radiolucent lines around some components and concerns about long-term fixation, the use of these devices should be reserved for situations in which other methods are inadequate or have already failed.

Adult↗

Fate of cementless acetabular components retained during revision total hip arthroplasty.

BACKGROUND: Removal of a well-fixed cementless acetabular component can result in increased operative time and postoperative morbidity. The objectives of this retrospective study were to determine whether retention of a well-fixed acetabular component at the time of isolated femoral revision was compatible with long-term socket survival. METHODS: The records of eighty-three consecutive patients (ninety hips) in whom a well-fixed cementless socket had been retained during revision of a femoral component were reviewed. The mean age of the patients was 48.7 years at the time of the primary arthroplasty and 54.1 years at the time of femoral revision. The radiographic analysis was based on anteroposterior radiographs and was performed by a single independent reviewer. The intraoperative criterion for stability of the socket was the absence of movement at the bone-implant interface during the application of direct pressure to the edges of the socket in four quadrants with use of a metallic pusher. RESULTS: At the time of the isolated femoral revision, no socket demonstrated a radiolucent line measuring >1 mm in any two zones and forty of the ninety hips had periacetabular osteolysis. The mean size of the osteolytic lesions was 5.71 cm(2) (range, 0.4 to 24.2 cm(2)), and twenty-eight of the forty hips underwent bone-grafting. The mean duration of follow-up was 9.7 years after the isolated femoral revision and 14.9 years after the primary arthroplasty. Five acetabular sockets were revised at a mean of 6.8 years after the femoral revision. Only one of these sockets had failed because of aseptic loosening. With revision of the acetabular component for any reason as the end point, the survival rate was 98.7% at five years and 93.5% at ten years after the femoral revision and 100% at ten years and 93.9% at fifteen years after the primary arthroplasty. No hip showed recurrence or expansion of periacetabular osteolysis. The prevalence of dislocation was 16% (fourteen of ninety). CONCLUSIONS: Revision of a stable, cementless acetabular component solely on the basis of its duration in vivo or the presence of periacetabular osteolysis does not appear to be warranted. Retention of the socket with grafting of larger periacetabular osteolytic lesions appears to be consistent with satisfactory socket longevity.

Acetabulum↗

The biomechanical results of total hip resurfacing arthroplasty.

BACKGROUND: With the advent of more wear-resistant bearings, there is renewed interest in resurfacing total hip arthroplasty. However, there is a paucity of information on the biomechanical results of this type of arthroplasty compared with those of contemporary total hip arthroplasty. METHODS: Using standardized radiographs, we measured and compared the biomechanical parameters that affect the hip joint reactive forces in fifty hips that had a metal-metal surface replacement with those parameters in forty hips that had a contemporary cementless total hip replacement performed during the same time-period by the same surgeon. RESULTS: On the average, the arthritic hips that were treated with metal-metal surface replacement had had a more valgus preoperative neck-shaft angle and less horizontal femoral offset than the normal, contralateral hips (p = 0.0003). After both the metal-metal surface replacements and the cementless total hip replacements, the hip center of rotation was medialized by approximately 6 mm. Both procedures were associated with an average increase in limb length of approximately 3 or 4 mm. After the metal-metal surface replacements, the horizontal femoral offset was essentially equal to the preoperative value, but both values averaged about 8 mm less than those on the normal, contralateral side (p < 0.00001). In the hips with a conventional total hip replacement, the horizontal femoral offset increased an average of 9.5 mm compared with the preoperative value and was an average of 5 mm more than that for the normal, contralateral hip (p = 0.001). CONCLUSIONS: The biomechanical results of total hip resurfacing depend on the preoperative anatomy of the proximal part of the femur. Limb lengthening of 1 cm can be achieved, but horizontal femoral offset is essentially unchanged by hip resurfacing. Horizontal femoral offset can be increased reliably with a contemporary total hip replacement. Arthritic hips of limbs that are more than 1 cm shorter than the contralateral limb or that have a comparatively low horizontal femoral offset may be better served by a contemporary total hip replacement. These biomechanical limitations should be considered in the selection of hips for resurfacing. LEVEL OF EVIDENCE: Therapeutic study, Level III-1 (case-control study). See Instructions to Authors for a complete description of levels of evidence.

Adult↗

The oblique posterior femoral condylar radiographic view following total knee arthroplasty.

BACKGROUND: It is often difficult to evaluate the posterior aspects of the femoral condyles after total knee arthroplasty. We have developed an imaging technique involving the use of the oblique posterior condylar view for the evaluation of the posterior aspects of the femoral condyles. The purpose of the present study was to compare the efficacy of this view with that of the true-lateral view. METHODS: Three orthopaedic surgeons analyzed fifty-five sets of radiographs (consisting of oblique posterior condylar and true-lateral views) for patients who had undergone total knee arthroplasty. The accuracy and reproducibility of the oblique posterior condylar view for the detection of radiolucencies were compared with those of the true-lateral view. RESULTS: The oblique posterior condylar view was significantly better than the true-lateral view for the detection of radiolucencies of the posterior aspects of the femoral condyles (p < 0.0005). CONCLUSIONS: Radiographic analysis with use of the oblique posterior condylar view is technically easy and is accurate for the evaluation of radiolucencies of the posterior aspects of the femoral condyles after total knee arthroplasty.

Aged↗

Minimum ten-year follow-up of a straight-stemmed, plasma-sprayed, titanium-alloy, uncemented femoral component in primary total hip arthroplasty.

BACKGROUND: The long-term results of total hip arthroplasty without cement have been reported only rarely. The purpose of the present study was to evaluate the minimum ten-year results of primary total hip arthroplasty performed with use of a proximally porous-coated, plasma-sprayed, straight-stemmed, titanium-alloy femoral component. METHODS: The clinical and radiographic results of a consecutive series of 105 total hip replacements in ninety-five patients were reviewed ten to twelve years postoperatively. The diagnosis was osteoarthritis for seventy-seven hips (73%). The clinical result was evaluated on the basis of the Harris hip score, complications, and thigh pain. A detailed radiographic analysis was performed at each follow-up visit. Kaplan-Meier analysis was performed to evaluate the survival of the femoral component. RESULTS: The average Harris hip score improved from 46 points preoperatively to 92 points postoperatively. The average pain score at the time of the most recent follow-up was 42 points, with eighty-three hips (79%) rated as pain-free. Thigh pain was identified in only two patients. All radiolucent lines were seen around the tip of the stem. All hips had some degree of femoral remodeling consistent with osseous ingrowth. No femoral component was revised, and no femoral component had evidence of loosening. Eight acetabular components were revised because of loosening and wear, and one was revised because of recurrent dislocation. One focal femoral osteolytic lesion was seen. CONCLUSIONS: This femoral component afforded durable fixation at ten to twelve years after primary total hip arthroplasty. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Adult↗

Prevention of deep-vein thrombosis after total knee arthroplasty in Asian patients. Comparison of low-molecular-weight heparin and indomethacin.

BACKGROUND: A prospective clinical study was performed to compare the efficacy of low-molecular-weight heparin and indomethacin for the prevention of deep-vein thrombosis after total knee arthroplasty in Asian patients. METHODS: One hundred and fifty patients undergoing total knee arthroplasty were randomly divided into three groups. One group consisted of fifty-one patients who received no prophylaxis with an anticoagulant (the control group), one consisted of fifty patients who received the low-molecular-weight heparin Fraxiparine (the Fraxiparine group), and the third consisted of forty-nine patients who received indomethacin (the indomethacin group). Bilateral ascending venography was performed preoperatively and at five, six, or seven days postoperatively. A third venogram was made at three months for patients who had had a deep-vein thrombosis. RESULTS: The prevalence of deep-vein thrombosis was 71% in the control group, 50% in the Fraxiparine group (p = 0.042), and 45% in the indomethacin group (p = 0.011). Only 28% of the deep-vein thromboses were symptomatic, and there were no pulmonary emboli. CONCLUSIONS: Compared with no prophylaxis, Fraxiparine and indomethacin significantly lowered the prevalence of deep-vein thrombosis after total knee arthroplasty. Prophylaxis against deep-vein thrombosis in the Asian population appears to be warranted. LEVEL OF EVIDENCE: Therapeutic study, Level I-1a (randomized controlled trial [significant difference]). See Instructions to Authors for a complete description of levels of evidence.

Adult↗

Débridement arthroplasty for primary osteoarthritis of the elbow.

BACKGROUND: Formal and more aggressive débridement procedures have been described for the treatment of advanced primary osteoarthritis of the elbow. However, the literature contains little information on the results of long-term follow-up. The purpose of this study was to evaluate outcomes at an average of ten years after débridement arthroplasties performed through a posteromedial approach. METHODS: Thirty-three elbows with primary osteoarthritis in thirty-two patients treated with débridement arthroplasty were available for clinical follow-up evaluation. Through a posteromedial approach, the flexor-pronator muscle origin was reflected from the medial epicondyle and the joint was opened, preserving the anterior oblique bundle of the medial collateral ligament. The ulnar nerve was decompressed in all patients. Osteophytes were removed from the anterior, medial, and posterior sides of the elbow joint. In nine elbows, osteophytes from the lateral compartment were removed through an additional lateral approach. The mean age at the time of the operation was fifty years. The mean duration of follow-up was 121 months, and nineteen elbows were followed for more than ten years. RESULTS: The mean preoperative limitation of extension of 31 degrees was reduced to 24 degrees, and the mean preoperative flexion of 101 degrees improved to 118 degrees (p < 0.001). The mean arc of movement improved by 24 degrees. The mean Japanese Orthopaedic Association elbow score was 83 points at the latest follow-up evaluation compared with 60 points preoperatively (p < 0.001). Of twenty-five patients who had performed heavy manual work, nineteen (76%) returned to their previous job or an equivalent job. At the latest examination of the nineteen elbows followed for more than ten years, the limitation of extension was found to have increased by 7 degrees compared with the limitation noted at one year (p < 0.009); the mean arc of flexion had remained the same. Three elbows required a reoperation. Overall, 85% of the elbows were satisfactory to the patients. CONCLUSIONS: Débridement arthroplasty through a posteromedial approach can provide stable and reliable long-term results with regard to relief of pain, gains in range of motion, and the patient's ability to return to his or her previous occupation. In our series, a modest loss of extension was observed at ten years, whereas the arc of flexion remained consistent.

Adult↗

Intraoperative fracture of the femur in revision total hip arthroplasty with a diaphyseal fitting stem.

BACKGROUND: In revision total hip arthroplasty, intraoperative split fractures and cortical perforation fractures are becoming a more common concern with the increasing use of diaphyseal fitting cementless stems. The purpose of this study was to evaluate the risk factors and frequency of intraoperative fractures with the use of these stems and their effect on radiographic and functional outcomes. METHODS: We performed a retrospective case-control study of 211 consecutive patients who had undergone revision hip arthroplasty with a diaphyseal fitting cementless stem between December 1998 and March 2002. Sixty-four patients sustained an intraoperative fracture of the femur. One hundred and fifteen patients were followed for a minimum of two years; function was analyzed with self-administered outcome questionnaires, and radiographs were evaluated for evidence of bone ingrowth into the femoral stem. RESULTS: Risk factors associated with an intraoperative fracture were a substantial degree of preoperative bone loss, a low femoral cortex-to-canal ratio, underreaming of the cortex, and the use of a large-diameter stem. The majority of the diaphyseal undisplaced linear fractures occurred at the distal end of an extended trochanteric osteotomy during stem insertion. Fracture due to cortical perforation occurred most often during cement removal. These intraoperative fractures had no significant effect on the functional outcome or radiographic evidence of bone ingrowth. CONCLUSIONS: There was a surprisingly high rate of intraoperative femoral fractures associated with the use of a diaphyseal fitting stem in revision total hip arthroplasty. Identification of risk factors such as preoperative bone loss and a low cortex-to-canal ratio may permit planning to avoid such fractures. However, the final functional and radiographic outcomes appear to have been unaffected by the fracture when it had been managed appropriately. LEVEL OF EVIDENCE: Prognostic study, Level II-1 (retrospective cohort study). See Instructions to Authors for a complete description of levels of evidence.

Activities of Daily Living↗

Periprosthetic humeral fractures after shoulder arthroplasty.

BACKGROUND: Currently, there is little information concerning periprosthetic humeral fractures after shoulder arthroplasty. Therefore, we reviewed our experience with these fractures to determine the results of treatment, the risk factors for periprosthetic fracture, and the rates of reoperation. METHODS: Between 1976 and 2001, nineteen postoperative periprosthetic humeral fractures occurred among 3091 patients who had undergone shoulder arthroplasty at our institution. Sixteen patients had a complete series of radiographs and were included in this study. The average time from the arthroplasty to the fracture was forty-nine months. Seven patients had severe osteopenia. Twelve fractures occurred at the tip of the prosthesis; of these, six extended proximally (type-A fractures) and six did not (type-B fractures). Three fractures occurred distal to the implant and extended into the distal humeral metaphysis (type-C fractures). One fracture occurred in the proximal metadiaphyseal region because of osteolysis. RESULTS: Six fractures healed after an average of 180 days of nonoperative treatment. Five fractures were treated operatively after an average of 123 days of unsuccessful nonoperative treatment. The remaining five fractures had immediate operative treatment. All sixteen fractures healed. One patient required multiple operations over a period of three years before union was achieved. With the exclusion of this patient and one other patient who received a custom prosthesis, the average time between the first operative procedure and union was 278 days. CONCLUSIONS: Our data do not clearly indicate the need for operative treatment of type-A fractures unless the humeral component is loose. A trial of nonoperative treatment may be considered for well-aligned type-B fractures that are associated with a well-fixed humeral component; however, operative intervention should be considered for type-B fractures that have not progressed toward union by three months. If the component is well fixed, open reduction and internal fixation may be performed. If the component is loose, revision with a long-stem component is recommended. For type-C fractures, a trial of nonoperative treatment is recommended.

Adult↗

Magnetic resonance imaging after total hip arthroplasty: evaluation of periprosthetic soft tissue.

BACKGROUND: The evaluation of periprosthetic osteolysis in patients who have had a total hip arthroplasty is challenging, and traditional imaging techniques, including magnetic resonance imaging and computerized tomography, are limited by metallic artifact. The purpose of the present study was to investigate the use of modified magnetic resonance imaging techniques involving commercially available software to visualize periprosthetic soft tissues, to define the bone-implant interface, and to detect the location and extent of osteolysis. METHODS: Twenty-eight hips in twenty-seven patients were examined to assess the extent of osteolysis (nineteen hips), enigmatic pain (five), heterotopic ossification (two), suspected tumor (one), or femoral nerve palsy (one). The results were correlated with conventional radiographic findings as well as with intraoperative findings (when available). RESULTS: Magnetic resonance imaging demonstrated the bone-implant interface and the surrounding soft-tissue envelope in all hips. Radiographs consistently underestimated the extent and location of acetabular osteolysis when compared with magnetic resonance imaging. Magnetic resonance imaging also disclosed radiographically occult extraosseous soft-tissue deposits that were similar in signal intensity to areas of osteolysis, demonstrated the relationship of these deposits to adjacent neurovascular structures, and allowed further visualization of hypertrophic synovial deposits that accompanied the bone resorption in twenty-five of the twenty-eight hips. CONCLUSIONS: Magnetic resonance imaging is effective for the assessment of the periprosthetic soft tissues in patients who have had a total hip arthroplasty. While not indicated for every patient who has pain at the site of an arthroplasty, these techniques can be effective for the evaluation of the surrounding soft-tissue envelope as well as intracapsular synovial deposits and are more effective than radiographs for the detection and evaluation of osteolysis, thus aiding in clinical management.

Adult↗

The influence of an anterior-posterior gliding mobile bearing on range of motion after total knee arthroplasty. A prospective, randomized, double-blinded study.

BACKGROUND: Range of motion is a crucial measure of outcome after total knee arthroplasty. In order for maximum flexion to occur, the femur must progressively shift posteriorly on the tibia, a movement that is known as femoral rollback. Mobile bearings with free anterior-posterior translation could improve knee flexion by allowing such motion. The purpose of the present study was to determine the influence of an anterior-posterior gliding mobile bearing on the postoperative range of knee motion in patients with an intact posterior cruciate ligament. METHODS: We performed a prospective, randomized clinical trial of fifty consecutive total knee arthroplasties that were performed with use of the LCS-Universal prosthesis. Participants were randomized to receive either a deep-dish rotating platform or a mobile bearing that allowed additional anterior-posterior translation, the latter of which requires an intact posterior cruciate ligament. The ranges of motion of the knees were assessed to detect a 15 degrees difference in the active non-weight-bearing range of motion with a power (1 - beta) of 20% and with the level of significance (alpha) set at 0.05. The translation of the mobile bearing was measured with use of a standardized ultrasound technique and was correlated with maximum knee flexion. The participants and the assessor were blinded throughout the study. RESULTS: At the time of the one-year follow-up evaluation, forty-eight knees were available for an intention-to-treat analysis. The mean active non-weight-bearing range of motion at one year was 113 degrees (95% confidence interval, 108 degrees to 118 degrees ) in the twenty-six knees that had received a rotating platform and 111 degrees (95% confidence interval, 115 degrees to 125 degrees ) in the twenty-two knees that had received an anterior-posterior gliding bearing (p = 0.57). In the latter group, a continuous rollback occurred in two knees. There was no significant correlation between knee flexion and anterior-posterior translation (r(2) = 0.015). CONCLUSIONS: The use of a mobile bearing that allowed free anterior-posterior translation did not regularly restore femoral rollback and did not improve range of motion after total knee arthroplasty compared with the findings seen in association with the use of a rotating platform.

Adult↗

Patient-reported outcome and survivorship after Kinemax total knee arthroplasty.

BACKGROUND: We examined the long-term survivorship and patient-reported outcomes at a minimum of ten years following primary total knee arthroplasty. We hypothesized (1) that the survival rate would be at least 90% at ten years; (2) that age, gender, body-mass index, and primary diagnosis would not affect the survival rate; and (3) that the functional status of patients would be comparable with that of an age and gender-matched normal population. METHODS: A total of 407 patients (523 knees) who had had primary total knee arthroplasty between January 1988 and April 1991 were identified. The mean age of the patients at the time of surgery was sixty-nine years, and 68% of the patients were women. At ten years, 165 patients (211 knees) had died; seven of these 211 knees had been revised before the time of death. Of the remaining 242 patients, 208 (86%) completed a questionnaire, which included the Western Ontario and McMaster University Osteoarthritis Index (WOMAC), the Short Form-36 (SF-36), and questions regarding patient satisfaction and revision surgery. In the group of patients who participated in the study, ten patients (eleven knees) had had a revision before the review. RESULTS: A total of eighteen knees were revised. Twelve knees were revised because of aseptic failure and, of these, nine were revised because of polyethylene wear. The probability of survival at ten years was 96.1% with revision for any reason as the end point (and 97.2% when only aseptic failures were considered). Because of the small number of failures, we were unable to draw conclusions about associations between failure and age, gender, diagnosis, and body-mass index. The mean WOMAC scores (and standard deviation) at the time of the evaluation were 88 +/- 17 for pain and 79 +/- 20 for function. The SF-36 scores were similar to those for an age and gender-matched normal population, with only the physical functioning score being significantly lower (p < 0.001) and with the general health score being significantly higher (p < 0.001). Patients generally were very satisfied with all aspects of the outcome. CONCLUSIONS: At ten years, the survival of the prosthesis was excellent and the majority of patients were functionally independent, had very little knee pain, and were very satisfied with the result. The health benefits of this total knee arthroplasty were maintained after a minimum duration of follow-up of ten years.

Activities of Daily Living↗