Biomedical subjects
Publications and source records attributed to T H Mallory.
Failed femoral total hip replacement components are frequently associated with bone loss. At the time of revision surgery, the goals are to create a construct that relieves pain, is stable, and preserves and enhances bone stock. This article discusses Materials and Methods, Indications, Operative Technique, and Results regarding onlay cortical allografting for the femur.
A 59-year-old healthy man presented with osteoarthritis of his left hip that was recalcitrant to nonoperative treatment. He subsequently elected to have arthroplasty of the hip performed. At 3 months after arthroplasty, he returned reporting progressive groin pain: most remarkable was a palpable mass in the groin region. An arteriogram showed a radiodense mass adjacent to the acetabulum, and a computed tomography scan with contrast confirmed a large false aneurysm originating from the common femoral artery. In this particular case, a pointed Hohmann retractor punctured the common femoral artery, creating the dynamics of the development of a false aneurysm. Primary suture repair of the vascular defect was performed, followed by a complete and uncomplicated recovery of the patient to full activity. Since this case, the authors have discontinued the use of pointed. Hohmann retractors and now use a blunt, rounded Hohmann retractor during total hip arthroplasty without compromising acetabular exposure. However, care must be taken in blunt retractor placement to avoid retractor slippage during the procedure. This case shows the need for awareness of potential mechanisms for vascular injury related to total hip arthroplasty.
The long-term behavior of total hip arthroplasty ultimately is determined by adaptive bone remodeling. Stress adaptation creating various degrees of metaphyseal bone atrophy has occurred with prostheses designed for tight distal fit and fill. This phenomenon has been explained as bone adaptation resolving the conflict between femoral component stiffness and bone flexibility. However, clinical observations indicate that a different premise may be operational when prostheses with tapered geometries are used. The results of four published reports (748 arthroplasties) using cementless femoral components of a tapered design were reviewed. The review found a low incidence of aseptic loosening (0.5%) and significant thigh pain (0.5%), and a radiographic incidence of proximal bone atrophy of 6%. In no case was the metaphyseal bone atrophy described as severe or extensive. These findings challenge the premise that reactive bone adaptation is related to the issues of femoral component stiffness exclusively and propose that femoral component geometry may have an influence on bone adaptation.
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Between 1984 and 1986, 177 nonconsecutive, primary total hip arthroplasties were performed in 150 patients using the Mallory-Head Porous femoral component (Biomet, Warsaw, IN) inserted without cement. Average time to follow-up evaluation for the entire population (including all early revisions) was 76 months (6.3 years). There were 10 revisions (6%) with an average time to revision of 50 months (4.2 years). Two revisions were for component undersizing; three revisions were for aseptic loosening; four revisions were for acetabular component failure and one revision was due to a femoral fracture secondary to trauma. At the most recent follow-up visit, the average Harris hip score for all hips increased from 41.5 before surgery to 86.8 (P < .001). Radiographic assessments yielded an average Engh fixation score of 20.7. The Kaplan-Meier survival estimate for the average time to follow-up evaluation was 0.98. Based on our patient selection criteria and excellent intermediate clinical and radiographic results, the initial design strategies of the Mallory-Head Porous femoral prosthesis have been confirmed.
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In an attempt to study the incidence of intraoperative femoral intercondylar fractures, two large series of posterior-stabilized total knee arthroplasty (TKA) systems were reviewed. Eight hundred ninety-eight nonconsecutive primary posterior-stabilized TKAs were compared with a second nonconsecutive series of 532 posterior-stabilized TKAs. Unique to the secondary TKA system is an intercondylar sizing guide to aid in verification of the intercondylar resection size. In the initial series, 40 distal femoral intercondylar fractures were noted (rate = 1:22; nondisplaced, 35; displaced, 5). In the secondary series, one displaced distal femoral intercondylar fracture occurred (rate = 1;532). The difference in the rate of fracture between the two populations was statistically significant (P<.001). Intraoperative distal femoral intercondylar fracture represents a potential complication of TKA and can be avoided with careful resection technique and size verification. No change in the postoperative rehabilitation program is required, however, for those patients identified with nondisplaced and intraoperative-stabilized displaced distal femoral intercondylar fractures.
Seventy-four primary total hip arthroplasties were performed in sixty-eight patients between August 1990 and September 1991. Clinical assessments were made with use of the Harris hip score and, specifically, the pain component of that score. The preoperative radiographs were digitally quantified for calculation of the so-called canal-to-calcar ratio and the so-called cortical index. The postoperative radiographs were evaluated for the percentage of the cross-sectional area of the femoral canal that was occupied by the prosthesis; subsidence of the prosthesis; and adaptive osseous changes, including hypertrophic cortical remodeling, osteolysis, formation of sclerotic radiolucent lines around the prosthesis, and formation of a pedestal at the tip of the prosthesis. The indication for the arthroplasty was osteoarthrosis in fifty hips (68 per cent), avascular necrosis in fourteen (19 per cent), congenital dysplasia in six (8 per cent), and another diagnosis in four (5 per cent). The average duration of follow-up was thirty-one months (range, eleven to forty-six months). The average Harris hip score (and standard deviation) was 75 +/- 16.8 points (range, 29 to 100 points), and the average score for the pain component was 37 +/- 7.5 points (range, 0 to 44 points). The average canal-to-calcar ratio of the hips was 0.44 (range, 0.32 to 0.74), and the average cortical index was 0.54 (range, 0.33 to 0.66). The average subsidence of the component was 0.6 centimeter (range, 0.0 to 2.3 centimeters). The average fill of the canal was 100 per cent proximally, 97 per cent at the middle of the stem, and 92 per cent distally as measured on the anteroposterior radiographs made immediately postoperatively and 100, 95, and 90 per cent, respectively, as measured on the lateral radiographs. A failure occurred in twenty-one hips (28 per cent) in twenty-one patients, with an average time to failure of 21 +/- 13 months (range, one to forty-four months). The Kaplan-Meier survival estimate (and standard error) for this population was 0.45 +/- 0.11 (confidence interval, 0.67 to 0.23) at forty-four months. The average subsidence of the components that failed was 0.7 centimeter (range, 0.1 to 2.3 centimeters). There was no significant relationship between failure of the component and the age or sex of the patient, the diagnosis, or the side of the operation. Postoperative severity of pain (p = 0.09) or subsidence (p = 0.08) alone did not reach significance for predicting outcome. The Harris hip score alone (p = 0.05), the Harris hip score in combination with subsidence of the femoral component (p = 0.01), and the pain component of the Harris hip score in combination with subsidence of the femoral component (p = 0.01) were all significant for predicting outcome. No other measured radiographic variable was predictive of failure. Despite optimization of the fit of the component within the femoral canal and the percentage of the cross-sectional area of the femoral canal occupied by the component, the clinical results indicated a high rate of failure. Thus, these criteria are not the only requisites for stabilization of these femoral components without cement. On the basis of these data, we have discontinued the use of these intraoperatively customized, non-porous, smooth femoral prosthesis.
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From 1981 through 1991, 3,032 primary total knee arthroplasties were performed using the Insall-Burstein Posterior Stabilized Condylar Prosthesis (IB-I, IB-II, and IB-II modified) (Zimmer, Warsaw, IN). Fifteen posterior dislocations occurred: 4 with the IB-I system occurring 2 or more years after surgery, 10 with the IB-II system (8 occurring 6 months after surgery and 2 occurring 2-3 years after surgery), and 1 with the IB-II modified system occurring 9 months after surgery. Statistically significant differences for the rate of dislocation between both the IB-I and IB-II modified arthroplasties versus the IB-II arthroplasties were found (P < .001). In an attempt to identify a cause for these dislocations, the authors retrospectively assessed the 15 dislocated cases with respect to sex, age, weight, height, preoperative and postoperative Hospital for Special Surgery scores, preoperative and postoperative alignment, preoperative versus postoperative reconstruction dimensions, patellar thickness and height, and postoperative flexion and compared the results with those patients who did not experience dislocation. Possible etiologies and mechanisms of dislocation were sought. There were no significant differences between the control and study groups for any variable assessed, with the exception of postoperative flexion, which averaged 118 degrees for the study group and 105 degrees for the control group (P < .001). Conservative management was successful in 11 cases. In September 1988 the IB-II system was introduced; modification of the tibial insert was made in January 1990.(ABSTRACT TRUNCATED AT 250 WORDS)
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Ninety-two patients (103 hips) treated with total hip arthroplasty (THA) were assessed before and after operation to determine nutritional status and any correlation with delayed wound healing. Parameters indicative of nutritional status (serum albumin and serum transferrin) were assessed, along with immunologic and anthropometric parameters. Delayed wound healing complicated 34 of the 103 (33%) THAs. The preoperative serum transferrin levels were significantly lower for patients who subsequently developed wound-healing complications. Patients treated with single-stage, bilateral procedures had substantially lower postoperative serum transferrin and serum albumin levels and significantly higher incidences of delayed wound healing (64%) than patients who had single joint procedures (25%). Only preoperative serum transferrin levels showed significant value in predicting which patients would have delayed wound healing. None of the other serologic variables, including serum albumin and total lymphocyte count, proved to be a predictor of delayed wound healing. The preoperative assessment of three variables--serum transferrin value, bilateral procedure, and patient age--resulted in the correct prediction of wound healing outcome in 79% of the patients. This preoperative information, in combination with postoperative monitoring of serum transferrin and albumin levels, should alert the physician to the approach of a malnourished state. The malnourishment is attributable to heightened demands on the body's basal energy requirements after major orthopaedic surgery and can increase morbidity and prolong the hospital stay.
A modified translateral approach to the hip, "the abductor muscle split", has been used when performing primary total hip arthroplasty. The results of this surgical approach in 50 patients with an average follow-up period of 2.8 years showed excellent restoration of abductor muscle function and gait without compromising surgical exposure. There was one case of postoperative dislocation. Heterotopic bone formation was not a clinical problem.