Minimal 10-year results of a tapered cementless femoral component in total hip arthroplasty.

A series of 120 primary total hip arthroplasties with minimal 10-year follow-up, in which a cementless, proximal-to-distal, dual-tapered geometry femoral component was used, was reviewed. At a mean follow-up interval of 12.20 years, a mean Harris hip score improvement of 38 points was calculated. Three (2.5%) femoral components were revised secondary to aseptic loosening, yielding a 97.5% survivorship. Thigh pain was mild or absent in 96.6% of the cases. Distal femoral osteolysis was observed in <2% of cases. The Harris hip score improvement, low incidence of severe thigh pain, high survivorship, and low incidences of significant stress shielding and distal osteolysis suggest excellent long-term results with the use of this uncemented tapered design, adding credence to the design rationale and justifying its continued use.

Short-term results of the M2a-taper metal-on-metal articulation.

A polyethylene-free, metal-on-metal acetabular system (M2a-taper [Biomet, Inc., Warsaw, IN]) was designed in an effort to improve total hip arthroplasty (THA) longevity. Minimum 2-year follow-up results involving 72 polyethylene liner THAs and 78 metal liner THAs from a multicenter, randomized, controlled, investigational device exemption study are reported. Mean Harris hip scores of 95.54 (polyethylene liner group) and 95.23 (metal liner group) were reported at mean follow-up intervals of 3.29 and 3.23 years. Radiographic evaluation revealed no evidence of early failure. No acetabular components have been revised or are pending revision. No statistically significant differences in the data were calculated between liner types except for the immediate postoperative (P=.0415) and minimum 2-year follow-up (P=.0341) angles of inclination. The M2a-taper metal-on-metal articulation may represent a viable alternative for THA in younger, higher demand patients.

Simultaneous bilateral total knee arthroplasties: who decides?

The purpose of the current retrospective review was to compare the results of 1498 patients having 1090 simultaneous bilateral total knee arthroplasties and 958 unilateral total knee arthroplasties in a 3-year period, focusing on perioperative complications, length of hospital stay, and discharge disposition. Gender, age, diagnosis, and weight were similar between the groups. Patients undergoing simultaneous bilateral total knee arthroplasties had statistically significant higher amounts of intraoperative blood loss, with more patients requiring blood transfusion, and a higher average number of units of blood transfused compared with patients undergoing unilateral total knee arthroplasty. Overall, a significantly higher incidence of gastrointestinal complications was reported in patients who had simultaneous bilateral knee arthroplasties compared with patients who had unilateral knee arthroplasty. Comparing age subgroups within the unilateral group revealed significantly higher incidences of pulmonary, neurologic, cardiac, and genitourinary complications among patients 80 years or older versus patients younger than 80 years. Patients having simultaneous bilateral arthroplasties who were 80 years or older had significantly higher incidences of pulmonary, neurologic, and cardiac complications than patients younger than 80 years in that same group. These results suggest that age, not procedure, has a more significant role in the perioperative morbidity of total knee arthroplasty. Based on the results from the current study and previous literature documenting patient preference, patient satisfaction, efficacy, and outcomes comparable with those of patients having unilateral total knee arthroplasty, the authors continue to offer patients the option of simultaneous bilateral total knee arthroplasties.

An algorithm for the posterior cruciate ligament in total knee arthroplasty.

The fate of the posterior cruciate ligament in primary total knee arthroplasty is controversial. An algorithmic approach is presented that is based on pathologic criteria for evaluating and treating patients with primary total knee arthroplasty that will aid in the posterior cruciate ligament decision-making process, producing more predictable procedures and outcomes. A consecutive series of the first 120 patients (171 knees) who had primary posterior cruciate-retaining arthroplasty and the first 120 patients (180 knees) who had primary posterior-stabilized arthroplasty with a minimum 5-year followup in which the Maxim Complete Total Knee System and the algorithmic approach were used were compared. No statistically significant differences in outcome between the groups were observed. Among the patients who had posterior cruciate-retaining arthroplasty, no revisions attributable to aseptic loosening have been reported at an average followup of 6.39 years. The average followup Knee Society total score was 162.16 points, with 91 (54.8%) knees having excellent outcome ratings. No revisions attributable to aseptic loosening have been reported among the patients who had posterior-stabilized arthroplasty at an average followup of 5.98 years. The average followup Knee Society total score was 158.05 points, with excellent outcome ratings reported in 96 (54.9%) knees. The use of a standardized algorithm has streamlined the treatment of patients having primary total knee arthroplasty, consistently providing excellent clinical results when either retaining or sacrificing the posterior cruciate ligament.

Linking the orthopaedic office-hospital continuum: results before and after implementation of an automated patient health history project.

This article introduces an innovative collaboration between an orthopaedic surgeon's office and the hospital to assure complete and accurate admission information without duplication. With the use of point-of-care software, the assessment process was re-tooled. This change involved the patient/family assuming responsibility for completing paper and pencil in-depth history and systems review that was then used as part of the evaluation process and inputted into the database allowing for more effective outcomes assessment. In this re-tooling process, the concept of "sharing" information with the partnering hospital was explored. In collaborative discussions, the nursing admission assessment was targeted as a process where there was significant duplication. In fact, much of the information required on the 4-page form was already assessed and documented in the office setting. Consequently it was agreed that the majority of the inpatient nursing history/admission assessment form would be replaced with the assessment completed by the professional office staff. Because of incompatible software, the systems could not be linked but a printed copy of the form was sent to the hospital. Results measuring satisfaction, timesaving, and compliance with JCAHO documentation standards were part of the evaluation. Patients and clinicians were satisfied with the process. There was a significant timesaving for the in-patient RN which facilitated more direct contact with the patient and family.

Noncemented acetabular component removal in the presence of osteolysis: the affirmative.

The strategy for retention or removal of the acetabular component to address osteolytic activity is becoming an increasingly debated issue among joint replacement surgeons. It is paramount to the success of the revision surgery to eliminate the particulate debris source and thoroughly debride and graft the periacetabular regions. Visualization and complete access to all periacetabular regions require acetabular component removal. The authors present an opinion on acetabular component removal and introduce an impaction grafting method for addressing periacetabular osteolysis. The intermediate results at an average of 41 months are excellent with one patient requiring rerevision of the acetabular component at 83 months postoperative because of aseptic loosening. The outcome of revision total hip arthroplasty has been shown to be inferior to primary total hip arthroplasty, with each following revision having less probability for success equaling the preceding procedure. However, it is the authors' opinion that removing the entire acetabular component is the most prudent choice to eliminate and to avoid the introduction of adverse variables such as particulate debris and component malposition and nonconformity, which may contribute to the continuation of the osteolytic process.

An in vivo determination of total hip arthroplasty pistoning during activity.

The purpose of this study was to determine to what extent hip joint separation occurs during normal gait on a treadmill and an abduction/adduction leg-lift maneuver in patients who have undergone total hip arthroplasty (THA). Eight patients who had a total of 10 successful unconstrained THAs (Harris Hip Scores >90) performed successive gait motions on an electronically powered treadmill and an abduction/adduction leg lift while under fluoroscopy. The fluoroscopic video images were analyzed using a 3-dimensional model-fitting technique that converts 2-dimensional fluoroscopic images into 3-dimensional real-time images. Hip joint separation was determined to be present if the amount of separation was >0.75 mm, the calculated linear error. During both activities, all 10 THAs experienced femoral head/acetabular component separation. For gait, the maximum amount of separation was 2.8 mm, while the minimum amount was 0.8 mm (average, 1.2 mm). For abduction/adduction leg lift, the maximum amount of separation was 3.0 mm, while the minimal amount was 1.7 mm (average, 2.4 mm). It appears that the femoral head separates from the acetabular component but remains in contact with the superior-most tip of the component. Potential detrimental effects resulting from hip joint separation include premature polyethylene wear and component loosening. Wear may be enhanced because of the creation of multidirectional wear vectors or excessive loads resulting from eccentric femoral head pivoting. These data may be valuable in hip simulation studies to better duplicate wear patterns observed in retrieval analysis.

Restoration of bone stock in revision surgery of the femur.

Three hundred and four femoral revisions were performed from 1987 to the end of 1990. All were done with cementless titanium calcar replacement prostheses, designed for proximal bone loading. Type III bone deficiencies were present in 160 femurs, all requiring supplemental cortical bone plates for bony augmentation. All grafts united and provided increased bone stock in the long term. Physiologic loading is important for graft remodeling and maturation. Hip scores have improved from an average Harris Hip Score of 44 to 84. Current survivorship at 10 years is 96%, and the revision rate is 3.2%. Thigh pain is mild in 3% of cases. There have been no late failures or distal lysis noted to date.

Surgical technique in total hip arthroplasty utilizing the anterolateral approach.

The surgical approach is an important element in the quality of total hip replacement. Adequate surgical exposure based upon thorough fundamental knowledge of anatomy facilitates surgery and ensure optimum results in total hip replacement. Several surgical exposure techniques are utilized and have been described in the literature; all stress the importance of visualization of the acetabulum and the proximal femur in affording an atraumatic, expedient entry into the hip joint. Additionally, surgical exposure should be versatile, allowing for development to easily accommodate revision scenarios.

Dislocation after total hip arthroplasty using the anterolateral abductor split approach.

The three basic surgical approaches used most commonly in total hip arthroplasty are transtrochanteric, posterior, and anterolateral. Complications related to each of these surgical approaches have been reported including dislocation, trochanteric nonunion, heterotopic ossification, neurovascular damage, postoperative limp, and implant malalignment. The anterolateral abductor split approach previously has been reported to allow ease of access into the hip joint, optimum joint visualization, protection of neurovascular structures of the hip, and predictable results for postoperative hip function restoration. Reviewing a large consecutive series of primary total hip arthroplasty cases (1518), the authors report an overall dislocation rate less than 1% (12:1518; 0.79%). Stratified by preoperative diagnosis, patients undergoing total hip arthroplasty after trauma, or presenting with congenital dysplastic hip are at the highest risk for postoperative dislocation. Primary total hip arthroplasty using the anterolateral, abductor split approach can minimize the rate of postoperative dislocation in the prevailing preoperative diagnostic categories.

Freehand resection of the patella in total knee arthroplasty referencing the attachments of the quadriceps tendon and patellar tendon.

A freehand technique of patellar resurfacing using anatomic references was prospectively evaluated. This technique utilizes an osteotomy beginning at the inferior pole of the patella just posterior to the insertion of the patellar tendon and is carried proximally posterior to the insertion of the quadriceps tendon. Evaluation of 55 total knee arthroplasties in 41 patients showed an average restored patellar thickness within 0.1 mm. The overall patellar thickness was restored to within 1 mm of its preoperative thickness in 50 (91%) of 55 knees. Patellar tilt was equal to or less than 4 degrees in 42 (89%) of 47 arthroplasties evaluated radiographically. The patellar thickness averaged 17.9 mm, well above the critical value of 15 mm reported in the literature.

Particulate debris presenting as radiographic dense masses following total knee arthroplasty.

Two cases of failed total knee arthroplasty associated with significant titanium debris that created massive radiographic densities are reported. The similarities of the failed total knee arthroplasties are that both involve titanium femoral components with failed metal-backed patellar components. At the time of surgical intervention, patellar polyethylene dissociation from metal-backed patellar components was noted with excessive burnishing and wear of the remaining metal-backed patellar component and of the titanium femoral component. Wear of the tibial polyethylene was noted in both cases. The titanium-on-titanium wear couple produced significant debris, resulting in large mass formation about the total knee arthroplasty. Additionally, there were loculated, fluid-filled sacks of titanium debris. Histologic sections performed for both cases revealed significant deposits of titanium in combination with polyethylene. In both cases, radiographs revealed the presence of large, radiodense masses. These cases illustrate that when considering etiologies for radiodense masses about total joint arthroplasty, particulate titanium debris resulting in mass formation must be added to the differential diagnosis.