Femoral bone regeneration subsequent to impaction grafting during hip revision: histologic analysis of a human biopsy specimen.

Cemented revision with impaction grafting shows encouraging early clinical results; postoperative biopsy specimens taken from the proximal femur in humans have demonstrated viable trabecular and cortical bone. Human radiographic studies also illustrate density changes within the proximal femur, consistent with remodeling of bone-graft. In an animal experiment, bone incorporation was shown in the proximal femur, but graft lysis was reported around the distal portion of the implant. We report on a patient who sustained a traumatic femoral fracture at the level of the tip of the femoral component 27 months after revision with impaction grafting and a collarless polished taper stem. At the time of open reduction and internal fixation of the fracture, we obtained circumferential biopsy specimens from the fracture site. Three distinct zones could be identified histologically: i) an inner zone consisting of bone-cement, fibrous tissue, and partially necrotic trabeculae with evidence of bone remodeling; ii) a middle zone consisting of viable trabecular bone and probable neocortex formation with fewer particles of bone-cement; and iii) an outer zone with viable cortex. Fibrous tissue was present around some of the incorporating bone-graft fragments, but no continuous fibrous membrane was present. Cement particles were identified, but no polyethylene debris was found by light microscopy. Biopsy specimens from the distal aspect of the prosthesis may not reflect changes seen proximally, but based on the available tissue, this case illustrated histological evidence of bone-graft remodeling after impaction grafting. These results are consistent with our expectations based on radiographic findings and clinical results.

Complex cemented revision using polished stem and morselized allograft. Minimum 5-years' follow-up.

The aim of this study was to evaluate the results of complex hip revision using a cemented, collarless and polished femoral stem design (CPT, Zimmer, Warsaw, In.) within a tightly impacted morselized allograft. We have now been using the impaction grafting technique in combination with the CPT stem (Zimmer) for 10 years in complex cases of severe bone loss. In this study we have elected to report only those patients who have been revised at least once before revision using the impaction grafting technique. All the patients in the study group have a minimum follow-up of 5 years after the impaction grafting revision. In total, 43 consecutive hips in 40 patients, 22 men and 18 women, with a follow-up time of between 5 and 7 years are included in the study. The complications related to the revised hip consist of three early dislocations managed by closed reduction. Two patients suffered from periprosthetic fracture, both managed with plate osteosynthesis. Two cementless sockets were revised due to aseptic socket loosening. The Endoklinik rating of preoperative bone loss for the revised hips was 2 in 13 hips, 3 in 23 hips, and 4 in 7 hips. During the first year 29 stems subsided 2-4 mm within the cement mantle. In 8 cases, a subsidence of 5-9 mm was measured. The subsidence was nonprogressive, and no subsidence occurred after the 1st year. The Charnley, D'Aubigne, Postel scoring (maximum 6 points) for pain improved from 2.2 points preoperatively to 4.4 postoperatively, function from 2.3 to 4.3, and movement from 2.3 to 4.1. In conclusion, the concept of impaction grafting in THR revision in our study has so far proven to be successful with good clinical results at 5 years despite the relatively high early subsidence of the femoral component.

Preliminary report of impaction grafting for exchange femoral arthroplasty.

Gie and Ling have described a method for femoral component revision using compressed morselized cancellous allograft and a cemented collarless polished taper stem. The authors report their early experience with this technique. Of the first 67 patients who had femoral exchange by impaction grafting, 60 were alive 2 to 5 years after hip revision; 2 hips failed because of late sepsis, and 5 patients were decreased. In 56 individuals available for review, the Harris Hip Score average was 90 points, with > 80% reporting no pain. On radiograph, 48% of the stems showed an average of 2.8 mm of subsidence in the polymethylmethacrylate mantle, but only 7% of the cement graft composites had subsided in the cortical tube. Lucent lines were rare, and in 93% of revised femurs the radiographs showed evidence of graft incorporation and bone remodeling. There were 6 reoperations in the group: 3 for late fracture of the femoral shaft and 3 for cup exchange (2 chronically dislocating, 1 loose). No evidence for femoral component loosening was found in this group. Further study is necessary, but these preliminary findings give rise to cautious optimism that this is a reliable method for femoral revision, reconstruction, and reconstitution.

Cemented collarless (Exeter-CPT) versus cementless collarless (PCA) femoral components. A 2- to 14-year follow-up evaluation.

The purpose of this study was to compare the intermediate results of total hp arthroplasty with a cemented, collarless, femoral prosthesis design (Exeter, Howmedica, Middlesex, UK and CPT, Zimmer, Warsaw, IN) with those of a cementless, collarless, porous-coated femoral component (PCA, Howmedica). A total of 151 hips in 128 patients were reviewed. In the cemented group, 85 Exeter-CPT prostheses were used in 71 patients with an average follow-up period of 6.5 years. In the uncemented group, 66 PCA prostheses were placed in 57 patients with an average follow-up period of 7 years. Harrington hip scores improved from 50.1 to 80.7 for the PCA group and from 49.5 to 87.3 for the Exeter-CPT group. The patient satisfaction rates were 89 and 96%, respectively. Sixty-eight patients with Exeter or CPT prostheses had excellent function and no significant thigh pain after 2 years. One Exeter stem was revised 10 years after the primary surgery because of aseptic osteolysis due to cement defect. Two Exeter sockets were revised because of aseptic loosening. In the PCA group, the incidence of thigh pain that persisted beyond 2 years was 39.4%, and there were high incidences of distal cortical hypertrophy (66.6%) and bead loosening (45.5%). Sixteen hips were revised for aseptic stem loosening of the socket. The cementless ingrowth stems failed earlier (around 5 years), whereas the cemented stems continued to perform well past 14 years. In this study, the cemented, collarless, tapered, femoral prosthesis gave results superior to those of the uncemented collarless, porous-coated anatomic design at an average follow-up period of 7 years (range, 2-14 years).

Revision hip arthroplasty with the use of cement and impaction grafting. Histological analysis of four cases.

The findings of radiographic studies have suggested that the cementing of an implant with a polished tapered stem into a bed of impacted bone allograft may provide adequate function of the joint and may restore bone in the proximal part of the femur. However, radiographs of hips with cancellous bone graft adjacent to cement are difficult to interpret, and the viability of impacted bone graft that is adjacent to cement and its capability for remodeling are unclear. To evaluate this interface further, we obtained biopsy specimens from the proximal part of the femur at the time of removal of trochanteric wires from four patients eleven to twenty-seven months after revision hip arthroplasty with cement and impaction grafting. Three relatively ill defined zones were identified histologically: an inner zone consisting of bone cement, fibrous tissue, and partially necrotic trabeculae with evidence of bone-remodeling; a middle zone consisting of viable trabecular bone and probable formation of so-called neocortex with fewer particles of bone cement; and an outer zone consisting of viable cortex. Fibrous tissue was present around some of the incorporating fragments of bone graft, but no continuous fibrous membrane was seen. Particles of cement were identified, but no polyethylene debris was visible on examination with light microscopy. The results demonstrated remodeling of bone and at least partial restoration of bone stock in the proximal part of the femur after revision arthroplasty with cement and impaction grafting.

The influence of the position of the patellar component on tracking in total knee arthroplasty.

The position of the patellar component and patellofemoral symptoms were assessed in a series of 72 cemented polyethylene patellar components in total condylar arthroplasties. A small (25 mm) component was used. The minimum follow up was 2 years and maximum 3 years. A lateral retinacular release was carried out in 22 knees. Clinical results were assessed by questionnaire and 86% had no patellofemoral symptoms. The mean postoperative patellar height was not changed compared to the preoperative height. Lateral placement of the patellar component was associated with both increased medial tilt and lateral subluxation. The component should be inserted so that its centre is slightly medial to the centre of the bone.

Impaction grafting: preliminary report of a new method for exchange femoral arthroplasty.

ABSTRACTGie et al described a method for femoral component revision using compressed morselized cancellous allograft and a cemented collarless polished taper stem. We have reviewed our first 37 exchanges performed in this manner. Results after 2 to 5 years have reflected few complications, a majority of satisfactory results, evidence of graft incorporation, and no mechanical loosening. Further study is necessary; however, these preliminary findings give rise to cautious optimism.

Effects of hypotensive anesthesia, nonsteroidal antiinflammatory drugs, and polymethylmethacrylate on bleeding in total hip arthroplasty patients.

One hundred forty patients ranging in age from 26 to 88 years, who had primary total hip arthroplasty (performed by the same surgeon and lateral surgical approach), were analyzed for intraoperative and postoperative blood loss. The factors affecting blood loss, which include bleeding disorders, medications, duration of surgery, the mean intraoperative blood pressure, and use of cement, were all recorded. A significant reduction in the intraoperative blood loss was observed in the group of patients with hypotensive anesthesia (greater than 20 mmHg drop in the mean intraoperative blood pressure using inhalation anesthetics) compared to the group of patients who did not have hypotensive anesthesia. The patients who had been on aspirin or nonsteroidal antiinflammatory drugs prior to surgery had increased intraoperative and postoperative blood loss compared to the patients who did not take such medications. The effect of cementing with methylmethacrylate on bleeding was also observed; the patients with uncemented implants had a greater blood loss after operation than the patients who had cemented prosthetic components.