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Biomedical subjects

John J Callaghan

Publications and source records attributed to John J Callaghan.

At least 37 records · Page 2Linked to original sources
PubMed2005

Kinetically critical sites of femoral head roughening for wear rate acceleration in total hip arthroplasty.

Polyethylene wear acceleration from (scratching) damage to the femoral head is a recognized hazard from constructs prone to generate third-body debris, but the phenomenon is nebulous and therefore often is subordinated to more direct and immediate considerations. To help delineate tangible quantitative relationships between counterface roughening and accelerated polyethylene wear, an experimentally validated sliding-distance-coupled finite element model of total hip replacement wear was adapted to incorporate regions of localized femoral head roughening. This computational formulation was used systematically to identify the sites on the femoral head for which a given severity of local roughening (parameterized in terms of roughening patch size and tribologic wear coefficient) was most consequential in terms of elevated polyethylene wear. Two such sites, of nominally comparable kinetic importance, were consistently evident throughout a wide range of roughening severities. These critical sites were located quasi-superiorly near the sagittal midline of the head, one slightly anterior and one slightly posterior of the coronal midline.

Arthroplasty, Replacement, Hip↗
PubMed2005

The John Insall Award: unicompartmental knee replacement: a minimum twenty-one-year followup, end-result study.

UNLABELLED: We report the results of a minimum 21-year followup of a consecutive series of 103 patients who had 136 Marmor cemented unicompartmental knee replacements done between 1975 and 1982. Patients were evaluated clinically and radiographically. At minimum 21-year followup 14 patients (19 knees) were alive, 87 patients (115 knees) had died, and only two patients (two knees) were lost to followup. The average age at surgery was 70.9 years. The average followup Hospital for Special Surgery knee score was 58. The average Knee Society final followup clinical and functional scores averaged 72 and 53 points, respectively. Nineteen knees (14%) were revised during the 21-year followup period: nine for progression of disease, eight for loosening, and two for pain, at an average of 10.6 years (range, 1-22 years). Of the 19 knees in the 14 patients who were still alive at final followup, seven (37%) were revised: two for tibial loosening, four for disease progression, and one for pain. Unicompartmental knee replacements in this relatively older age group of patients performed well at minimum 21-year followup. Although we are encouraged by these results, only 22% were done in patients who were younger than 65 years at the time of surgery and the results in this group were significantly less durable. LEVEL OF EVIDENCE: Therapeutic study, Level IV-1 (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Aged↗
PubMed2005

Staggered bilateral total knee arthroplasty performed four to seven days apart during a single hospitalization.

BACKGROUND: The purpose of this study was to evaluate the types and prevalence of complications associated with bilateral total knee replacement performed four to seven days apart during a single hospitalization and to compare them with those associated with bilateral knee replacement performed sequentially under the same anesthetic session or staged unilateral replacements performed during separate hospitalizations. METHODS: Using a computerized database and medical records, we retrospectively evaluated 332 consecutive patients who underwent bilateral total knee replacement performed by two surgeons. A total of 241 patients underwent staggered bilateral knee replacement with the procedures performed four to seven days apart during one hospitalization, twenty-six underwent sequential bilateral total knee replacement, and sixty-five underwent staged bilateral knee replacement performed during two separate hospitalizations. The data on major complications, including death, return to operating room, myocardial infarction, and pulmonary embolism, and on minor complications, including atrial fibrillation, deep-vein thrombosis, and urinary tract infection, were evaluated. RESULTS: Patients undergoing sequential bilateral total knee replacement and staged bilateral knee replacement had an overall rate of complications that was 2.5 times higher than that of the staggered group. Major complications were rare in all groups, but they occurred most often in the staged bilateral replacement group. The overall rate of complications for the patients who had staggered bilateral knee replacement (13%) was significantly less (p = 0.0009) than that for the patients who had sequential bilateral knee replacement (35%) or staged bilateral knee replacement (31%). The length of inpatient stay for those with staggered total knee arthroplasty was four days longer than that for the sequential arthroplasty group (p = 0.0001). CONCLUSIONS: Staggered bilateral total knee replacement, with the procedures performed four to seven days apart in a single hospitalization, is a safe and practical method for performing bilateral total knee replacement.

Adult↗
PubMed2005

Cemented rotating-platform total knee replacement. a concise follow-up, at a minimum of fifteen years, of a previous report.

We previously evaluated 119 consecutive total knee arthroplasties that were performed in eighty-six patients with use of the cemented LCS (low contact stress) rotating-platform system with an all-polyethylene patellar component. The average age of the patients at the time of surgery was seventy years (range, thirty-seven to eighty-eight years). The purpose of this study was to report the updated results at a minimum follow-up of fifteen years. Thirty-seven patients (fifty-three knees) were living, and no patient was lost to follow-up. No knee was revised because of loosening, osteolysis, or wear. Three knees required a reoperation (two for periprosthetic fractures and one for infection). No component was revised as a part of the reoperations. Osteolysis was present in three knees. No knee had radiographic signs of component loosening, and there were no dislocated bearings. The average range of motion was from 1 degrees of extension to 105 degrees of flexion. The average clinical and functional Knee Society scores were 43 and 49, respectively, at the preoperative evaluation and 85 and 58 at the time of the final follow-up. We concluded that the cemented LCS rotating-platform knee performed well, with durable clinical and radiographic results at a minimum follow-up of fifteen years.

Activities of Daily Living↗
PubMed2004

Why knees fail: lessons learned.

This article reviews the changing modes of failure in total knee arthroplasty over the past decade. Reasons for failure include polyethylene wear, aseptic loosening, instability, infection, arthrofibrosis, malalignment, or malposition, deficient extensor mechanism, periprosthetic fracture, and isolated patellar resurfacing. Awareness of the modes of failure may lower the prevalence of failure and aid in developing designs and techniques to better address the problems.

Arthroplasty, Replacement, Knee↗
PubMed2004

Are all cementless acetabular components created equal?

The cementless acetabular components used over the past 2 decades have varied in type of ingrowth fixation, supplemental fixation, locking mechanisms, and bearing surface. We evaluated 15-year follow-up results from 2 cementless acetabular components: the Harris-Galante I (HG; Zimmer, Warsaw, IN) and the PCA (Howmedica, Rutherford, NJ), in terms of revision and radiographic loosening. Three of the 120 HG I acetabular components were revised for wear and osteolysis without loosening. Seventeen of the 100 PCA components were revised for aseptic loosening (with or without osteolysis). Including those cases revised, 21 PCA acetabular components were loose radiographically, and no HG I component was loose. At least with these 2 first-generation designs, differences were seen in performance of the acetabular component in terms of revision and loosening at 15 years.

Adult↗
PubMed2004

Use of a constrained tripolar acetabular liner to treat intraoperative instability and postoperative dislocation after total hip arthroplasty: a review of our experience.

Constrained acetabular components have been used to treat certain cases of intraoperative instability and postoperative dislocation after total hip arthroplasty. We report our experience with a tripolar constrained component used in these situations since 1988. The outcomes of the cases where this component was used were analyzed for component failure, component loosening, and osteolysis. At average 10-year followup, for cases treated for intraoperative instability (2 cases) or postoperative dislocation (4 cases), the component failure rate was 6% (6 of 101 hips in 5 patients). For cases where the constrained liner was cemented into a fixed cementless acetabular shell, the failure rate was 7% (2 of 31 hips in 2 patients) at 3.9-year average followup. Use of a constrained liner was not associated with an increased osteolysis or aseptic loosening rate. This tripolar constrained acetabular liner provided total hip arthroplasty construct stability in most cases in which it was used for intraoperative instability or postoperative dislocation.

Adult↗
PubMed2004

Results of Charnley total hip arthroplasty at a minimum of thirty years. A concise follow-up of a previous report.

The purpose of the current study was to update the results of a prospective, single-surgeon series of primary Charnley total hip arthroplasties performed with cement. This investigation is one of the first studies in which hips treated with total hip arthroplasty with cement were followed for a minimum of thirty years. Twenty-seven patients (thirty-four [10.3%] of the hips in the initial study group) were alive at a minimum of thirty years postoperatively. These patients served as the focus of the present study. Revision because of aseptic loosening of the acetabular component was performed in 7.3% (twenty-three) of the hips from the original study group (excluding those revised because of infection or dislocation) and 26% (eight) of the hips in the living cohort. Revision because of aseptic loosening of the femoral component was performed in 3.2% (ten) of the hips from the original study group (excluding those revised because of infection or dislocation) and 10% (three) of the hips in the living patients. Since the twenty-five-year review, three hips were revised (one because of acetabular loosening, one because of femoral loosening, and one because of instability). This end-result study demonstrated the remarkable durability of cemented Charnley total hip replacements over a span of three decades, with 88% of the original prostheses intact at the time of the final follow-up or at the patient's death.

Aged↗
PubMed2004

A constrained liner cemented into a secure cementless acetabular shell.

BACKGROUND: Constrained acetabular components have been used to treat hips with recurrent instability following total hip arthroplasty and hips that demonstrate instability during revision surgery. In such hips, when a secure cementless acetabular shell is present, the surgeon can cement a constrained liner into the existing shell. The purpose of this study was to evaluate the clinical and radiographic outcome of this technique with use of a tripolar constrained liner that was cemented into a well-fixed cementless acetabular shell. METHODS: Between 1988 and 2000, constrained liners were cemented into thirty-one well-fixed cementless acetabular shells at three centers. The average age of the patients at the time of the index surgery was 72.1 years, and the indications for the procedure were recurrent hip instability in sixteen hips and intraoperative instability in fifteen hips. The patients were evaluated with respect to the clinical outcome and radiographic evidence of shell loosening and osteolysis. RESULTS: At an average duration of follow-up of 3.9 years, twenty-nine liners (94%) were securely fixed in the cementless shells and two constrained liners had failed. One liner failed because it separated from the cement, and one failed because of fracture of the capturing mechanism. Both hips were successfully revised with another cemented tripolar constrained liner. No acetabular component demonstrated radiographic evidence of progressive loosening or osteolysis. CONCLUSIONS: A constrained tripolar liner cemented into a secure, well-positioned cementless acetabular shell provides stability and durability at short-term follow-up. Careful attention to the preparation of the liner, the sizing of the component, and the cementing technique are likely to reduce the failure of this construct, which can be used for difficult cases of total hip instability.

Acetabulum↗
PubMed2004

Salvage of a recurrently dislocating total hip prosthesis with use of a constrained acetabular component. A concise follow-up of a previous report.

We previously reported the results at a mean of five years following the use of a tripolar constrained acetabular component to treat recurrently dislocating total hip prostheses. In this study, we report the results after longer follow-up, with emphasis on the prevalence of implant loosening, osteolysis, and later recurrent instability. Fifty-five patients treated with a total of fifty-six constrained acetabular components because of recurrent dislocations of a total hip prosthesis (average, six dislocations; range, two to twenty dislocations) were followed for an average of 10.2 years (range, 7.0 to 13.2 years) or until death. Four (7%) of the fifty-six hips had a subsequent dislocation or failure of the device. Three femoral components (5%) and two acetabular components (4%) were revised because of aseptic loosening. One hip was revised because of osteolysis. We concluded that this constrained acetabular component provides durable protection against additional dislocations without substantial deleterious effects on component fixation. We use this device to treat recurrent dislocation when other modalities are unlikely to be effective.

Acetabulum↗
PubMed2004

Cementless acetabular fixation at fifteen years. A comparison with the same surgeon's results following acetabular fixation with cement.

BACKGROUND: Loosening of the acetabular component is the major long-term problem associated with total hip arthroplasty with cement. The purpose of the present study was to evaluate the minimum thirteen-year results associated with cementless acetabular components that had been inserted by a single surgeon and to compare them with the results associated with cemented acetabular components that had been inserted by the same surgeon. METHODS: One hundred and twenty consecutive, nonselected primary total hip replacements were performed in 108 patients with use of a Harris-Galante-I cementless acetabular component and a cemented femoral component with a 28-mm head. The patients were evaluated clinically with use of a standard terminology questionnaire, and they were evaluated radiographically for loosening, component migration, wear, and osteolysis. The rates of revision for aseptic loosening and radiographic evidence of loosening for this cohort were compared with the rates for four previously reviewed consecutive series of hips in which the acetabular component had been inserted with cement. All patients were managed by the same surgeon, were followed for thirteen to fifteen years, and were evaluated with use of the same two criteria (revision and loosening) as the end points for Kaplan-Meier analysis. RESULTS: Sixty-six patients (seventy-two hips) were living and forty-two patients (forty-eight hips) had died after thirteen to fifteen years of follow-up. No acetabular component had been revised because of aseptic loosening, and no acetabular component had migrated. With revision of the acetabular component for any reason as the end point, the survival rate was 81% +/- 8% at fifteen years. With revision of the acetabular component for clinical failure (osteolysis, wear, loosening, or dislocation) as the end point, the survival rate was 94% +/- 8% at fifteen years. Among the seventy hips with at least thirteen years of radiographic follow-up, five had pelvic osteolysis and three had had revision of a well-fixed acetabular component because of pelvic osteolysis secondary to polyethylene wear. The mean linear wear rate was 0.15 mm/yr (0.12 mm/yr when one outlier was excluded). CONCLUSIONS: In terms of fixation, Harris-Galante-I cementless acetabular components performed better than did cemented 22-mm-inner-diameter Charnley acetabular components as well as 28-mm-inner-diameter all-polyethylene and metal-backed acetabular components that had been inserted by the same surgeon. However, the rate of wear was greater in association with the Harris-Galante-I cementless components than it was in association with the Charnley cemented all-polyethylene components.

Acetabulum↗
PubMed2004

The Agility total ankle arthroplasty. Seven to sixteen-year follow-up.

BACKGROUND: We previously reported the intermediate-term results with the early version of the Agility total ankle replacement, a unique design that takes advantage of arthrodesis of the tibiofibular syndesmosis for tibial component support. The purpose of this study was to report longer-term results of this procedure in the treatment of disabling ankle arthritis. METHODS: We conducted an independent review of all Agility total ankle replacements performed by a single surgeon between 1984 and 1994. Follow-up evaluation consisted of completion of a validated ankle osteoarthritis scale and a short questionnaire and a review of the radiographs. All radiographs were evaluated for evidence of the development of progressive hindfoot arthritis, nonunion of the tibiofibular syndesmosis, progressive radiolucent lines, osteolysis, and component subsidence. RESULTS: One hundred and thirty-two arthroplasties were performed in 126 patients. After a mean follow-up period of nine years, thirty-three patients (thirty-six implants) had died, fourteen patients (11%) had a revision of the implant or an ankle arthrodesis, and one had the leg amputated because of an unrelated cause. Of the remaining seventy-eight patients (eighty-one ankles), sixty-seven (sixty-nine ankles) were followed clinically. More than 90% of them reported that they had decreased pain and were satisfied with the outcome of the surgery. We found modest differences in a comparison of the pain and disability scores with those of age-matched controls. Of the 117 ankles that had been followed radiographically for a minimum of two years, twenty-two (19%) had progressive subtalar arthritis, seventeen (15%) had progressive talonavicular arthritis, and nine (8%) had a syndesmosis nonunion. Eighty-nine (76%) of the 117 ankles had some evidence of peri-implant radiolucency. CONCLUSIONS: Arthrodesis of the tibiofibular syndesmosis impacts the radiographic and clinical outcomes with the Agility total ankle replacement. The relatively low rates of radiographic hindfoot arthritis and revision procedures at an average of nine years after the arthroplasty are encouraging. Agility total ankle replacement is a viable and durable option for the treatment of ankle arthritis in selected patients.

Ankle Injuries↗
PubMed2004

Implementing capsule representation in a total hip dislocation finite element model.

Previously validated hardware-only finite element models of THA dislocation h ave clarifiedhow various component design and surgical placement variables contribute to resisting the propensity for implant dislocation. This body of work has now been enhanced with the incorporation of experimentally based capsule representation, and with anatomic bone structures. The current form of this finite element model provides for large deformation multi-body contact (including capsule wrap-around on bone and/or implant), large displacement interfacial sliding, and large deformation (hyperelastic) capsule representation. In addition, the modular nature of this model now allows for rapid incorporation of current or future total hip implant designs, accepts complex multi-axial physiologic motion inputs, and outputs case-specific component/bone/soft-tissue impingement events. This soft-tissue-augmented finite element model is being used to investigate the performance of various implant designs for a range of clinically-representative soft tissue integrities and surgical techniques. Preliminary results show that capsule enhancement makes a substantial difference in stability, compared to an otherwise identical hardware-only model. This model is intended to help put implant design and surgical technique decisions on a firmer scientific basis, in terms of reducing the likelihood of dislocation.

Arthroplasty, Replacement, Hip↗
PubMed2003

Kinematics, kinetics, and finite element analysis of commonplace maneuvers at risk for total hip dislocation.

Dislocation remains a disturbingly frequent complication of total hip arthroplasty (THA). Over the past several years, increasingly rigorous biomechanical approaches have been developed for studying dislocation, both experimentally and computationally. Realism of the input motion challenge data has lagged behind most other aspects of this body of work, and anterior dislocation maneuvers remain unstudied. To enhance realism of biomechanical studies of dislocation, motion data are here reported for ten THA-aged subjects, each repeatedly performing seven maneuvers known to be dislocation-prone. An optoelectronic motion tracking system and a recessed force plate captured the kinematics and ground reaction forces of these maneuvers. Using an established inverse dynamics model to estimate hip joint loading, 354 motion trials were evaluated using an existing finite element model of THA dislocation. Worst-case-scenario THA constructs were simulated (22 mm femoral head, acetabular cup orientations at the limit of the accepted safe zone), in order to deliberately induce impingement and dislocation. The results showed a high incidence of computationally predicted dislocation for all movements studied, but also that risk was very maneuver-dependent, with patients being six times more likely to dislocate from a low-sit-to-stand maneuver than from stooping. These new motion data hopefully will help facilitate systematic efforts to reduce the incidence of dislocation.

Activities of Daily Living↗