Avoiding patellar complications in total knee replacement.

Patellofemoral complications are common after total knee replacement (TKR). Leaving the patellar unsurfaced after TKR may lead to complications such as anterior knee pain, and re-operation to surface it. Complications after patellar resurfacing include patellar fracture, aseptic loosening, patellar instability, polyethylene wear, patellar clunk and osteonecrosis. Historically, patellar complications account for one of the larger proportions of causes of failure in TKR, however, with contemporary implant designs, complication rates have decreased. Most remaining failures relate to patellofemoral tracking. Understanding the causes of patellofemoral maltracking is essential to prevent these complications as well as manage them when they occur.

Wound healing in total joint replacement.

Satisfactory primary wound healing following total joint replacement is essential. Wound healing problems can have devastating consequences for patients. Assessment of their healing capacity is useful in predicting complications. Local factors that influence wound healing include multiple previous incisions, extensive scarring, lymphoedema, and poor vascular perfusion. Systemic factors include diabetes mellitus, inflammatory arthropathy, renal or liver disease, immune compromise, corticosteroid therapy, smoking, and poor nutrition. Modifications in the surgical technique are necessary in selected cases to minimise potential wound complications. Prompt and systematic intervention is necessary to address any wound healing problems to reduce the risks of infection and other potential complications.

Alternatives to revision total knee arthroplasty.

Most problems encountered in complex revision total knee arthroplasty can be managed with the wide range of implant systems currently available. Modular metaphyseal sleeves, metallic augments and cones provide stability even with significant bone loss. Hinged designs substitute for significant ligamentous deficiencies. Catastrophic failure that precludes successful reconstruction can be encountered. The alternatives to arthroplasty in such drastic situations include knee arthrodesis, resection arthroplasty and amputation. The relative indications for the selection of these alternatives are recurrent deep infection, immunocompromised host, and extensive non-reconstructible bone or soft-tissue defects.

Inter- and intraobserver variability of radiographic measurements of knee alignment.

To evaluate the variability of radiographic measurement of knee alignment by different observers, as well as repeated measurements by the same observer, standing anteroposterior radiographs of both knees of 36 patients presenting with knee pain were analyzed. Four physicians independently measured the anatomic tibiofemoral angle of both knees for a total of 72 measurements for each observer. These measurements were then repeated 1 month later in a random and blinded fashion. The same handheld goniometer was used for all measurements. The second measurement was within 3.1 degrees of the first measurement 95% of the time, and within 4 degrees 98% of the time. The maximum difference was 6 degrees. Among all four observers, measurements were within 3.7 degrees of each other 95% of the time with a maximum difference of 6 degrees. In addition to radiographic measurement, one physician also performed clinical measurement of knee alignment on these 36 patients using the same handheld goniometer. The clinical measurement was within 5 degrees of the same clinician's radiographic measurement 95% of the time with a maximum difference of 7 degrees. This variability in measuring radiographic alignment should be considered when making decisions on the need for surgical intervention or when evaluating results of procedures that relate to coronal plane alignment of the knee.

Total hip replacements done without cement after acetabular fractures: a 4- to 8-year follow-up study.

Twenty-one patients (21 hips) underwent cementless total hip replacement surgeries for previous acetabular fractures. The mean age at the time of hip replacement was 52 years (range, 23-78 years). The mean follow-up was 65 months (range, 48-104 months). One hip required revision of the stem secondary to a periprosthetic femur fracture from a fall at 3 months after surgery. Good to excellent clinical rating was achieved and maintained in 19 hips. Radiographic evaluation demonstrated stable cup and stem fixation in 17 and 15 hips. Only 1 patient with radiographic loosening of the components was sufficiently symptomatic. The results in this series appeared slightly better than those reported previously in hip replacements done with cement at comparable medium-term follow-up. The mechanical failure rates remained high in this patient population: 19% for the cups and 29% for the stems.

A comparison of the cost effectiveness of one-stage versus two-stage bilateral total hip replacement.

Forty patients underwent 80 bilateral primary total hip replacements (THRs) under the same anesthesia (one-stage). Forty other patients who underwent unilateral primary THRs during the same time interval were selected to match the first 40 patients with regard to age, sex, diagnosis, weight, medical comorbidity, type of prosthesis used, and perioperative management protocol. An assumption was made in that each unilateral case represented the first side of bilateral THRs performed during two separate hospitalizations (two-stage). Analysis of the total hospital charges submitted to the insurance companies was made between the groups. On average, there was a 24% reduction (P<.05) for each case if bilateral THRs were done in one stage. This was primarily due to a significant decrease (P<.05) in the length of hospital stay in the one-stage group. There was no difference between the two groups in the operative time, estimated blood loss, or perioperative complications.

Cementless total hip replacement in patients with developmental dysplasia of the hip.

This study was conducted to evaluate the clinical and radiographic results of 22 total hip replacements done in 17 consecutive patients for coxarthrosis due to developmental dysplasia or dislocation of the hip. All operations were done using an anterior approach without trochanteric osteotomy. Standard cementless prostheses were used in all cases. There was no custom-designed prosthesis used. The acetabular cup was placed in an anatomic position in the true acetabulum in every case. Bulk autograft was necessary to reconstruct the deficient acetabular roof in only 2 hips. The average follow-up was 63 months (range, 40 months to 95 months). The average Harris Hip Score was improved from a preoperative value of 35 (range, 24 to 46), to 96 (range, 79 to 100) at final follow-up. To date, no revision has been done. Three hips showed radiographic evidence suggestive of aseptic loosening (2 stems and 1 cup), but the clinical results remain satisfactory. There is no incidence of dislocation, sciatic nerve palsy, or infection.

Total hip arthroplasty performed without cement in patients with femoral head osteonecrosis who are less than 50 years old.

Seventy-two cementless total hip arthroplasties were performed by a single surgeon in 58 patients with the diagnosis of femoral head osteonecrosis. All patients were less than 50 years old (mean, 37 years). The mean follow-up was 84 months with a minimum of 48 months. Good-to-excellent results were maintained at final follow-up in 94% of the hips. Revision rate was 1.5% each for the cups and the stems. Mechanical failure rate was 7.6% for the cups, and 6% for the stems. If the results were analyzed excluding the data from the group of patients who received the Mittelmeier prostheses, the mechanical failure rates for the cups was 0% and for the stems was 4.2%. The probability of survival for the entire series using revision as the endpoint was 96.9% at 11 years. Survival probability decreased to 88.5% if radiographic failures were included. Excluding the Mittelmeier prostheses, survival probability was estimated to be 100% for the cups using both revision and radiographic failures as endpoints; for the stems, the survival probability was 98.0% using revision as the endpoint and 95.8% including radiographic failures. Femoral osteolysis was observed in 1.5% of the hips. No hip had acetabular osteolysis. No measurements of polyethylene wear were attempted in this study. These results appeared superior to total hip arthroplasties done with early cementing techniques in this population of young patients with femoral head osteonecrosis.

Unsatisfactory results of a first-generation modular femoral stem implanted without cement. A 4- to 9-year follow-up study.

Eighty primary total hip arthroplasties were performed using a first-generation modular femoral stem inserted without cement. Modular distal sleeves made of methacrylate were used in 33% of the hips. Dorr type B or C femoral geometry was present in 80% of the cases. The mean follow-up period was 81 months with a minimum of 48 months. Satisfactory clinical results were observed in 74% of the hips at the final follow-up visit. Revision of the stem had been performed in 14% of the hips, all for aseptic loosening. The overall mechanical failure rate was 48%. Canal fill by the stem was not any better with the sleeves than without. The incidence of failure, however, was less in those hips in which sleeves were used. Femoral osteolysis was present in 19% of the hips. The experience with this particular stem design has been disappointing.

Early innominate osteotomy as a treatment for avascular necrosis complicating developmental hip dysplasia.

The clinical and radiographic outcomes of 25 patients with avascular necrosis (AVN) of the femoral head complicating developmental hip dysplasia (DDH) were analyzed. Seven patients (group A) had an innominate osteotomy 1-3 years after the ischemic insult. Eight patients (group B) had a pelvic osteotomy between 5 and 10 years after the insult, and 10 patients (group C) did not have a pelvic osteotomy. The minimum follow-up period was 10 years from the time of the ischemic insult. The hips in group A patients (early osteotomy) showed significantly better radiographic outcomes as assessed by a modified Severin grading. These patients also had less pain, fewer gait disturbances, and required fewer additional procedures for limb length discrepancy or greater trochanteric overgrowth.

Total hip replacements using the ceramic Mittelmeier prosthesis.

One hundred twelve consecutive primary total hip replacements were performed for osteoarthritis or osteonecrosis by a single surgeon using the Mittelmeier ceramic prosthesis without cement between January 1983 and July 1984. Ninety-three of these hips were followed prospectively to a minimum of 60 months and a median of 108 months. Five (5.4%) hips have been revised for loosening. Of the remaining hips, 77 (87.5%) were rated clinically satisfactory. Cumulative survival probability using revision as endpoint was estimated to be 92.7% at 5 years and 87.9% at 10 years. However, overall mechanical failure rates were 21.5% for the cup and 22.6% for the stem. There was no case of either femoral or acetabular osteolysis observed.

Cementless total hip arthroplasties using ceramic-on-ceramic articulation in young patients. A minimum 5-year follow-up study.

Cementless total hip arthroplasties were performed in 25 consecutive young patients (27 hips), with a mean age of 36.5 years, using prostheses that offered ceramic-on-ceramic articulation. The median follow-up period was 75 months, with all hips being followed a minimum of 5 years. Revision surgery was necessary in one hip at 60 months for fracture of the cup. Ninety-six percent of the remaining hips were rated good or excellent clinically using the Harris hip scale. Radiographic loosening of one or both components was evident in 3 hips. There was no incidence of femoral or acetabular osteolysis observed at follow-up periods of 5 to 8 years.

Cemented total hip arthroplasty in patients with osteonecrosis. A 6-year minimum follow-up study of second-generation cement techniques.

Twenty patients with osteonecrosis of the femoral head underwent 28 total hip arthroplasties using cement from 1981 to 1985. Femoral reconstruction was by use of second-generation cement techniques. Twenty-four hips in 17 patients were available for review at a mean follow-up period of 7.7 years. The mean age at surgery was 55 years. Clinical evaluation demonstrated 79% excellent, 4% good, and 4% fair results. Three hips (12.5%) required revision for loosening. The cumulative probability of survival was estimated to be 85.7% at 10 years. Second-generation cement techniques and implant designs did improve the clinical results in this high-risk group; however, the overall mechanical failure rate remained high.

Total hip arthroplasty using the Zweymuller stem implanted without cement. A prospective study of consecutive patients with minimum 3-year follow-up period.

A prospective study was undertaken over a 2-year period to evaluate the clinical efficacy of using the Zweymuller femoral component (Allopro, Berne, Switzerland) in cementless total hip arthroplasty. Forty consecutive patients (46 hips) were included for final evaluation. Ninety-four percent of the femurs were classified as Dorr class B or C before surgery. The mean follow-up period was 50 months (median, 48 months). Ninety-eight percent of the hips were rated good or excellent clinically. No stem was classified as definitely loose. No hip has required any reoperation. There was no incidence of femoral or acetabular osteolysis up to 6 years.

Unwashed wound drainage blood. What are we giving our patients?

Wound drainage blood was collected after total joint arthroplasty was completed in 13 consecutive patients. Peripheral blood samples were collected in the recovery room and at 6 hours postoperatively for all 13 patients. A standard enzyme-linked immunosorbency assay was done to quantify tumor necrosis factor-alpha, interleukin-1 alpha, interleukin-6, and interleukin-8 levels in the samples. At 6 hours postoperatively, the levels of cytokines were elevated significantly in the peripheral and drainage blood serum. In particular, the drainage blood serum had the most dramatic increase for all cytokines, which was significant. Reinfusion of unwashed filtered postoperative wound drainage blood has been shown not to be entirely benign; pyrogenic transfusion reaction is the most commonly reported adverse effect, but hemodynamic instability with hypotension and even myocardial infarction have been reported. The cause of these adverse events has not been defined clearly, but may be secondary to the infusion of cytokines. The present study showed the presence and significant elevation of the cytokine levels in the wound drainage blood. A comprehensive review of the literature revealed that unwashed drainage blood is a relatively dilute blood product lacking normal clotting factors and having numerous other undesirable components that may mitigate against its routine use in lieu of predeposited autologous or homologous blood. This is of interest because there is evidence indicating that wound drainage blood reinfusion may be unnecessary in total joint arthroplasty when autologous blood is available. Use of drains in this surgery also may be unnecessary and has been shown to increase the amount of blood loss and the need for transfusion.

Use of cemented all-polyethylene and metal-backed acetabular components in total hip arthroplasty. A comparative study.

The results of 115 primary total hip arthroplasties (97 patients) performed using the Charnley system and contemporary cementing techniques were reviewed. Fifty-five all-polyethylene cups and 60 metal-backed cups were used. The mean follow-up period was 84 months. No statistically significant difference was noted between groups for radiographic loosening and no cup has been revised to date. Survival analysis did not reveal a statistically significant difference between groups. Although all-polyethylene cups had significantly greater polyethylene thickness, no difference was noted for rate of wear. Increased loosening of the metal-backed cups was not observed. Polyethylene thickness is increased by the use of 22-mm heads and this may have accounted for the lack of difference in loosening rates of the all-polyethylene and metal-backed cups.

Oblique femoral osteotomy in cementless total hip arthroplasty. Prospective consecutive series with a 3-year minimum follow-up period.

Success of total hip arthroplasty using cementless implants is dependent on intimate contact of the prostheses with viable host-bone and achievement of optimal fit and rigid implant fixation. A technique of oblique femoral osteotomy has been used to correct proximal femoral deformity and to facilitate difficult revision surgery in selected cases. This prospective study included 26 osteotomies performed in 25 consecutive patients with a minimum follow-up period of 3 years. The median follow-up period was 50 months. Eighty-four percent of the reconstructions remained in situ at the final follow-up examination, with 81% of them rated clinically excellent or good. Three stems were revised for aseptic loosening at a mean interval of 46 months. One additional femoral revision was necessary for nonunion of the osteotomy. Two of the remaining stems were classified as radiographically loose. Although oblique femoral osteotomy serves as a useful adjunct surgical technique in difficult femoral reconstructions, nearly 25% of the hips in this study either failed or were loose at the medium-term follow-up examination. Long-term success of this technique with cementless prostheses remains to be defined.

Effect of preoperative autologous blood donation and intraoperative and postoperative blood recovery on homologous blood transfusion requirement in cementless total hip replacement operation.

BACKGROUND: Blood transfusion is often necessary in operations for total hip replacement (THR). This study was done to investigate the efficacy of three different methods of autologous blood conservation and transfusion in patients undergoing primary THR without cement. STUDY DESIGN: One hundred fifty-five patients with osteoarthritis underwent unilateral cementless THR using normotensive general anesthesia performed by a single surgeon. The patients were divided into four groups depending on which conservation method was used. Ten different demographic and hematologic parameters were recorded and analyzed by using analysis of the variance and multiple regression methods. RESULTS: All three methods were effective in reducing the need for homologous blood transfusions. The greatest benefit was realized when both preoperative autologous blood donation and intraoperative salvage using the Cell Saver were combined. The addition of postoperative salvage and retransfusion of wound drainage blood using the Solcotrans System did not significantly reduce further the chance of homologous blood transfusions. CONCLUSIONS: The data from this study were similar to previously published reports. Regression analysis confirmed the correlation among the different variables studied. We currently offer preoperative donation and intraoperative salvage with the Cell Saver to patients undergoing cementless total hip replacement.